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tT. E. PAGE, C.H., LITT.D. 

t E. CAPPS, PH.D., LL.D. t W. H. D. ROUSE, litt.d. 

L. A. POST, l.h.d. E. H. WARmNGTON, m.a., f.b.hist.soc. 








A. L. PECK, M.A., Ph.D. 

FELLOW OF Christ's college, cambridob 


F. H. A. MARSHALL, C.B.E., Sc.D., F.R.S. 











First printed 1937 

Revised and reprinted 1945, 1955 

Revised and reprinted 1961 


Printed in Great Britain 




Foreword . • . . . . . . 3 

Introduction ...... 8 

Text and Translation .... 52 



Introduction ...... 436 

Text and Translation .... 440 

Index to Parts of Animals • • . 543 

Index to Movement and Progression of 

Animals. ...... 552 

From quotations which I had seen, I had a high notion 
of Aristotle's merits, but I had not the most remote notion 
what a wonderful man he was. Linnaeus and Cuvier have 
been my two gods, though in very different ways, but they 
were mere schoolboys to old Aristotle. 

Charles Darwin to 
William Ogle, on 
the publication of 
his translation of 
The Parts of Ani- 
mals, 1882. 


A. E. P. and L. A. P. 


Aristotle refers to the De partibiis animalium as an 
inquiry into the causes that in each case have deter- 
mined the composition of animals. He does not, 
however, employ the category of causation in the 
manner normally adopted by men of science, since 
in this book caus es are always considered in relati on 
to ends or purpose s, and design is reg^arded as havi ng 
had~a far larger share in the origin and developn^ nt 
of l iving struct ures tnan that allotted to ji£C£asity. 

In the Histona animalium the parts themselves are 
described, for although this work is to some extent 
physiological, its main object was to deal with the 
anatomy of the organism. The D<? pa riibus animalium , 
on the other hand, is almost^ exghisivelyiphyj&ieleg^ical 
and tele ological, and trea ts of the fu nctioiiS-QfL the 
parts. But Aristotle's position was that o f a telep - 
logist only in a li mited degrj ej_iiQr_iieapppRrs.,to 
h avie fak^ jOhaT view ot life whjc hBergson calls_jthe 
doctriryeo f internal j^n^ lity^ (that is to say, that each 
indTvTdTiaTToratany rate each species, is made for 
itself, that all its parts conspire for the greatest good 
of the whole, and are intelligently organized in view 
of that end but wi thout regard for othe r_or^a]Qlsms 
or kinds of organisms). Since every organ or part 
of the body was held to have its peculiar function, 
the existence of vestigial or rudimentary organs M^as 

A 2 3 


unrecognized. This was the doctrine of internal 
finahty which was generally accepted until Darwin 
elaborated his theory of Natural Selection. The 
wider doctrine of external finality, according to 
which living beings are ordered in regard to one 
another, never gained acceptance among scientific 
philosophers, and the only indication that Aristotle 
ever adopted it is furnished by a passage in which 
he suggests that the mouth in Selachians is placed 
on the under surface so as to allow their prey to 
escape while the fish are turning on their backs 
before taking their food ; but even this he qualified 
by the suggestion that the arrangement served a 
useful end for the fishes in question by preventing 
them from indulging in the harmful habit of gluttony. 
The De part'ihus a?iimaliu)?i opens with an intro- 
duction devoted to general considerations. This is 
followed by a discussion of the three degrees of 
composition, the first degree being composition of 
physical substances, the second degree, of homo- 
geneous parts or tissues, and the third, of hetero- 
geneous parts or organs. The tissues referred to are 
blood, fat, marrow, brain, flesh, and bone. After 
describing these, the organs are dealt with, and a 
consideration of their respective functions, first in 
sanguineous animals {i.e. in Vertebrates), and secondly 
in bloodless animals (i.e. Invertebrates), occupies the 
remainder of the book. The account given of the 
physiology of the blood is especially interesting, and 
it is noteworthy that Aristotle understood something 
of the nature of the process of absorption whereby 
the food becomes converted into nutriment which is 
carried by the blood to all parts of the body. He 
supposed, however, that the matter derived from the 


gut passed first to the heart in the form of vapour 
or serum, and that it was there converted into true 
blood by a process of concoction. Aristotle knew 
nothing of the real nature of respiration, and he 
regarded the lungs as serving to temper the bodily 
heat by means of the inspired air. He was also 
entirely ignorant of the fact that the blood passes 
back to the heart and lungs after supplying the 
tissues and organs with nourishment. On the other 
hand, he fully appreciated the existence of excretory 
organs, the function of which was to remove from the 
body such substances as could not be utilized. In 
this category are included fluids such as bile, urine, 
and sweat. In the section on the gall-bladder, as 
in so many other passages in his works on natural 
history, it is truly remarkable how correct Aristotle 
is in his statements. He points out that the gall- 
bladder is not found either in the horse and ass or 
in the deer and roe, but is generally present in the 
sheep and goat. In the light of the knowledge that 
he possessed, therefore, Aristotle could scarcely have 
adopted a theory about this organ which has found 
expression in certain modern writings. According 
to this theory the gall-bladder is present in the sheep 
and ox because, these being ruminating animals, 
bile is only required at certain particular times when 
food passes into the intestine, whereas in the horse, 
which does not chew the cud, but yet is constantly 
eating, food is continually passing into the intestine 
and consequently a perpetual flow of bile is desirable. 
Since the gall-bladder is present in the non-ruminating 
pig but absent in the ruminating deer and roe, it 
is obvious that this theory cannot be consistently 


It is interesting to speculate about the school of 
research workers who must have contributed in 
providing material for this and the other works on 
natural science ascribed to Aristotle — who they were, 
the circumstances under which they lived, and what 
manner of facilities were available for their investiga- 
tions — for it would seem certain that no man single- 
handed could possibly have acquired such a vast body 
of knowledge, hardly any of which could have been 
derived from earlier observers. Yet the work in its 
completed whole seems to show the mark of one 
master hand, and its uniform character and the clear 
line of teleological reasoning that runs through it 
have been well brought out in Dr. Peck's translation. 
But putting aside its philosophical implications, the 
book consists of an attempt at a scientific record of 
all the apparently kno\vn facts relating to animal 
function. These are considered comparatively and 
as far as possible are brought into relation A^ith one 
another. And thus, as the earliest text-book on 
animal physiology in the world's history, this treatise 
will ever make its appeal, not only to the classical 
philosopher, but to all who are interested in the origin 
and growth of biological science. 

F. H. A. M. 



Title. The traditional title of this treatise is not a very 
informative one. The subject of the work is, how- 
ever, stated quite clearly by Aristotle at the begin- 
ning of the second Book in these words : "I have 
already described mth considerable detail in my 
Researches upon Animals what and how many are the 
parts of which animals are composed. We must now 
leave on one side what was said there, as our present 
task is to consider what are the causes through which 
each animal is'as I there described it " (646 a 7 foil.). 
The title ought therefore to be " Of the Causes of the 
Parts of Animals," and this is the title actually applied 
to it by Aristotle himself (at De gen. an. 782 a SI).** 
Even so, the word " parts " is misleading : it in- 
cludes not only what we call parts, such as limbs and 
organs, but also constituents such as blood and 
marrow.** Perhaps, therefore, no harm is done by 
leaving the accepted (and convenient) Latin title 
Zoological The De partibus, as well as the other treatises 
'^°^^*' contained in this volume, forms a portion of Aris- 
totle's zoological works. The foundation of these is 
the Historia animalium, or Researches about Animals^ 
in nine books (the tenth is generally held to be 

• For the meaning of Cause see note below, p. 24. 
" See note on " part " below, p. 28. 



spurious), in which observations are recorded, and 
consequent upon this are the treatises in which 
Aristotle puts forward theories founded upon these 

An animal is, according to Aristotle, a " concrete 
entity " made up of " matter " and " form." Hence, 
in the De partihus Aristotle treats of the causes on 
account of which the bodies — the " matter " — of 
animals are shaped and constructed as they are, in 
general ; in the De incessu he deals specially with 
the parts that subserve locomotion. In the De anima 
he proceeds to consider Soul — the " form " of an 
animal. In the remaining treatises, of which De 
motu, included in this volume, is one, he deals with 
what he calls the functions " common to body and 
Soul," among which he includes sensation, memory, 
appetite, pleasure, pain, waking, sleeping, respira- 
tion, and so forth (see De sensu 436 a). The complete 
scheme is set out below : 

I. Record of observations, 

Historia animalium. 10 (9) books. 

II. Theory based upon observations. 

(«) 1 

De partihus 

De incessu 

(b) De anima 

treating of the way in 
which the " matter " 
of animals is ar- 
ranged to subserve 
their various pur- 

(treating of the "form" 
3 books j of animals — the 
[ Soul. 


4 books 

1 book 



Parva valuralia — 

De motu ani- 

De generatione 

1 book 

5 books 

treating of the func- 
tions " common to 
body and Soul," and 
in particular of 
some special de- 
partments of ani- 
mal behaviour. 

The section (6) is necessary to the completeness of 
the scheme, but as it has given rise to a whole depart- 
ment of study, it is usually treated apart from the rest. 
Thus the main bulk of the zoological and biological 
works may be taken to consist of the three great 
treatises, Historia animalium, De partibus animalium, 
and De generatione animalium. It was these which, 
through translations made from the Arabic, were 
restored to the West by those who revived scientific 
studies at the beginning of the thirteenth century. 
Date of The late D'Arcy W. Thompson, in the prefatory 
*^°°^t£n. ^ote to his translation of H.A.,^ wrote : " I think it 
can be shown that Aristotle's natural history studies 
were carried on, or mainly carried on, in his middle 
age, between his two periods of residence at Athens," 
i.e. in the Troad, in Lesbos and in Macedonia, between 
the years 347 and SS5 : and this view has recently 
received convincing support from Mr. H. D. P. Lee,'' 
who bases his argument upon an examination of the 
place-names in H.A. This is opposed to the view 
which has been current for some years past,*' that 
the zoological works belong to a late period in Aris- 
totle's life, and has important consequences for the 
reconstruction of Aristotle's philosophical develop- 

* The Works of Aristotle translated, vol. iv., Oxford, 1910. 

" C.Q. xlii. (1948), 61 if. 

* See W. D. Ross, Aristotle, and W W. Jaeger, Aristotle. 



ment, which cannot be dealt with here. It may, 
however, be remarked that, as Thompson said, it 
would follow that we might legitimately proceed to 
interpret Aristotle's more strictly philosophical work 
in the light of his Mork in natural history. But apart 
from these considerations, the great importance of 
the zoological works is that they represent the first 
attempt in Europe to observe and describe in a 
scientific way the individual living object. 

Throughout the De pariibus Aristotle endeavours to Teleology. 
provide a Final Cause " to explain the facts which 
he records — some purpose which they are supposed 
to answer ; and Causes of this sort are by far the 
most common in his treatise. His outlook is there- 
fore justly described as ** teleological " ; but it is 
important not to read too much into this description. 
Aristotle is never tired of telling us that Nature makes 
nothing and does nothing " without a purpose " ; 
but if we ask what that purpose is we may find that 
the answer is not quite what we had expected. 
Plato's notion of the " form " tended to divert his 
attention from individuals through a hierarchy of 
successive " forms " ; but for Aristotle " form " is 
not independent of matter : form must be embodied 
in some matter, that is, in individuals. Thus we find - 
all through that Aristotle cannot long keep his eyes 
from the individual wherein the form is actually 
embodied, because it, after all, is the End, the 
crowning achievement of the efforts of the four 
Causes. This outlook controls the arrangement of 
Aristotle's treatise. Since all processes of production 
are determined by the nature of the product which 
is to result from them, it is the fully developed product 
which we must first make it our business to observe, 

" The four Causes are dealt with in a separate note, p. 24. 



and when we have discovered what are its actual 
characteristics we may then go on to work out its 
Causes and to examine the processes by which it was 

Synoi)sis I give a brief synopsis and a contents-summary 
umu^lry. of the De partibus : 


Introduction : Methods. 

Composition of Substances : Three modes : 

(1) The primaiy substances. 

(2) The " uniform " parts. 

(3) The " non-uniform " parts. 
Consideration of (1) Hot, cold, solid, fluid. 

(2) Uniform parts : {a) fluid, {h) solid. 

(8) Non-uniform parts, as follows : — 
External parts of animals. 
Internal parts of blooded animals. 
Internal parts of bloodless animals. 
External parts of bloodless animals. 
External parts of blooded animals (resumed), 
(a) Vivipara. (6) Ovipara. 


Book I. 
639 a 15 ch. 1 Introduction. On the Method of Natural 

Two questions propounded : 

(1) Are we to begin with the ultimate 
species and describe its characteristics, 
or with those that are common to 

many species 



639 b 8 (2) (Put in three ways) : 

(a) Are we to take first the phenomena, 
and then proceed to their Causes ? 

(b) \Mnch is the primary Cause, the 
Final or the Efficient (Motive) ? 
(Answered immediately : The 
Final ; with a reference also to the 
influence of Necessity.) 

(c) Are we to discuss first the pro- 
cesses by which the animal is 
formed, or the characteristics of 
it in its completed state ? 

Answer to question (2). 

\Ve must begin with the phenomena, 
then go on to the Causes, and the forma- 
tive processes — or, in other words, the 
Final Cause concerns us first and foremost. 
This differs from the practice of the early 
philosophers, who concerned themselves 
with the Material Cause, though some- 
times also with the Efficient (Motive) 
CiQse. We must begin at the End, not 
at the beginning. 
G40 b 17 Thus we must consider not merely the 

primary substances, but the " uniform " 
parts, which are made out of them, and 
also the " non-uniform " parts. In doing 
this, we shall be paying attention to the 
Formal Cause, which is more important 
than the Material Cause : the animal as 
a finished whole is more significant than 
the substances out of which it was made. 

640 b 80 But mere form or shape is not enough : 

" shaped matter " is not an animal. 
*' Form " in its full and true sense involves 
** Soul " : " Soul " somehow is the 
animal's Efficient and Final Cause. Act- 
ually, it is not Soul in its entirety, but 


some " portion " of Soul which fulfils this 

641 b 10 Thus the universe and the living objects 

in it are the products of something 
analogous to human art : they are con- 
trolled by a Final Cause. 

642 a 1 But Necessity also has its place in the 

universe — 

not (1) " absolute " necessity 
nor (2) " coercive " necessity 
but (3) " conditional " necessity. 
These two Causes, the Final Cause and 
Necessity, set the stage for our piece. 

642 b 5 ch. 2 Criticisms of dichotomy as a method of 

classification of animals. 
644 all ch. 4 The correct method of classification is by 

groups, such as Birds and Fishes. 

644 a 23 Answer to question (1). 

We must deal with groups, not species (e.g. 
Bird, not Crane), ancLH-here a species does 
not belong to a largengroup, we must deal 
with species, not individuals (e.g. Man, 
not Socrates). 

644 b 21 ch. 5 An Exhortation to the study of animals. 

645 b 1 Final summary of the Method, combining 

answers to both the original questions : 

(1) First we discuss the attributes common 
to a group ; 

(2) Then we give the explanation of them. 

Book II. 
646 a 8 ch. 1 Purpose and outline of the Treatise : Our 

subject is the causes of the parts of 



6-46 a 13 Three modes of composition : 

(1) Out of the " elements " or dynameis 
(hot, cold, fluid, solid). 

(2) The uniform parts (bone, flesh, etc.). 

(3) The non-uniform parts (face, hand, 

The relation of them to each other, and 
the way in which the Causes control this 
647 a 3 Parts may be divided into : 

(a) Instrumental parts (non-uniform). 

(b) Media of sensation (uniform). 

647 a 25 The faculty of sensation has its seat in the 

heart, which is thus uniform ; but it is 
also non-uniform, as it has to do with 

647 b 10 ch. 2 The uniform parts, generally. Variations 

occur in each of them, as is illustrated by 
the example of Blood. 

648 a 20 Resumption of the Three modes of com- 

position : 

649 b 9 (1) The primary substances : meaning of 

" hot," " cold," " solid," " fluid," with 
special reference to Blood. This merges 
into a discussion of 
(2) The Uniform parts. 

Blood. Fibres, Intelligence and sensi- 
tivity, and " temperament " generally. 
651 a 20 ch. 5 Lard and Suet (forms of Blood). 

651 b 20 ch. 6 Marrow (a form of Blood). 

652 a 24 ch. 7 The Brain. 

653 b 19 ch. 8 Flesh — the " part " par excellence — 

and its counterpart. 
Bones, and their counterparts, and 
parts similar to Bone, 
ch. 10 (3) The Non-uniform parts of animals. 
(This occupies the rest of the work.) 



655 b 28 General statement of the three organs 

indispensable to animals. 

656 a 14 Head : Brain. Sense-organs. 

657 a 12 ch. 11 Ears. 

657 a 25 ch. 13 Eyes, etc. (ch. 14 : Eyelashes 

and digression on Hair). 

658 b 27 ch. 16 Nostrils (esp. the Elephant's). 

659 b 20 Lips. 

660 a 14 ch. 17 Tongue. 

Book IH. 

661 a 84 ch. 1 Teeth. 

661 b 27 (Note on " the more and less.") 

662 a 16 Mouth. 
662 a 34 Beak. 
662 b 23 ch. 2 Horns. 

664 a 13 ch. 3 Neck : Oesophagus. 

664 a 36 Larynx and windpipe. 

664 b 20 Epiglottis. 

665 a 27 ch. 4 Internal Parts of Blooded Animals: 

Viscera : 

665 b 5 Heart. 

667 b 15 ch. 5 Blood-vessels (Great Blood-vessel and 

Aorta, and generally). 

668 b 33 ch. 6 Lung. 

669 b 13 ch. 7 (Why viscera are double, and other 

remarks.) Liver and Spleen. 

670 b 32 ch. 8 Bladder. 

671 a 26 ch. 9 Kidneys. 

672 b 8 ch. 10 Diaphragm. 

673 b 4 ch. 11 Membranes. 

673 b 12 ch. 12 Variations in the Viscera (Liver and 


674 a 9 ch. 14 Stomach and Intestines. 

675 b 29 Jejunum. 

676 a 7 ch. 15 Rennet. 

Book IV. 
676 a 23 ch. 1 General. Internal parts of Ovipara, 


676 b 16 ch. 2 Gall-bladder and Bile. 

677 b 15 ch. 3 Omentum, 

677 b 37 ch. 4 Mesentery. 

678 a 27 ch. 5 Internal Parts of Bloodless Animals 

(Insects, Testacea, Crustacea, Cephalo- 
pods). With special reference to the 
Sepia's " ink," and the Sea-urchin's 
" ova." 

681 a 10 Creatures intermediate between animals 

and plants. 

682 a 30 External Parts of Bloodless Animals : 

682 a 35 ch. 6 Of Insects. 

683 b 4 ch. 7 Of Testacea. 

683 b 25 ch. 8 Of Crustacea. 

684 b 7 ch. 9 Of Cephalopods. 

685 b 30 ch. 10 External Parts of Blooded Animals : 

(a) Vivipara, {b) Ovipara. 

(o) Vivipara : 

686 a 6 Head and Neck. 

686 a 24 Hands and Feet and relative propor- 

tion of limbs. Beginning from Man, 
whose position is upright, there is a 
gradation of declivity in the animals, 
continuing to the plants, which are 

687 a 2 Nature's habit in assignment of organs. 

The structure of the human hand, etc. 

688 a 12 Breast. 

689 a 4 Excretory organs. 

689 b 2 Rear parts. 

690 a 5 Hoofs, hucklebones, etc. 
690b 12 (6) Ovipara: 

690 b 18 (i) Serpents and Quadrupeds. 

692 b 4 (ii) Birds. 

695 b 2 (iii) Fishes. 



697 a 15 (c) Intermediate Creatures: 

Seals and Bats. 

697 b 27 Conclusion. 

Method of A glance at the summary Avill show clearly the 
ficaUon. order of subjects which Aristotle lays down in the 
first book to be followed in a treatise such as the 
one in which he is engaged. 

First, (A) to describe the parts of animals as they 

are observed to be ; and 
then, (B) to give an account of their causes, and 

their formative processes." 
Under (A) the order of preference is to be : first, 
the parts (1) common to all animals \ (2) 
where necessary, those common to a 
group of animals only ; and lastly, (3) in 
exceptional instances, those peculiar to a 
single species. 
Also, it will be seen how Aristotle works out this 
scheme in the three books which follow. Before 
considering that, however, we should notice that 
Aristotle has a great deal to say about the correct 
classification of animals — or rather, against the in- 
correct classification of them. Chiefly, he inveighs 
against the method of dichotomy ; and his chief 
objection to it is a simple and effective one — that it 
does not work. It forces us to assign to each species 
one distinguishing mark, and one only (64-2 b 21 — 
643 a 24). And it cuts off kindred species from each 
other on the strength of some quite subordinate 

" De partibus is concerned chiefly with the causes and less 
with the processes. 


characteristic (642 b 10 foil.). The right method, 
says Aristotle, is to follow popular usage and divide 
the animals up into well-defined groups such as 
Birds and Fishes." And this leads him to distinguish 
two stages of difference : 

(a) Cases in which the parts differ " by excess or 
defect " — as in different species of the same 
genus or group. 
(6) Cases in which the resemblance is merely one 

of analogy — as in different genera. 
Examples of (a) : differences of colour and shape ; 
many or few ; large or small ; 
smooth or rough ; e.g. soft and 
firm flesh, long and short bill, 
many or few feathers. 
(b) bone and fish-spine ; nail and 
hoof ; hand and claw ; scale and 
(Reff. for the above, De part. an. 644 a 11-b 15 ; Hist, 
an. 486 a 15-b 21. See also Gen. An. (Loeb), Introd.) 

The doctrine of differences of" excess and defect," "The more 
or, as Aristotle also calls them, of " the more and ^^'^ ^^^^' 
less," may usefully be compared with that which 
underlies the modern theory of Transformations, and 
the comparison of related forms. Indeed, Professor 
D'Arcy Thompson asserts that "it is precisely . . . 
this Aristotelian * excess and defect ' in the case 
of form which our co-ordinate method is especially 
adapted to analyse, and to reveal and demonstrate 
as the main cause of what (again in the Aristotehan 
sense) we term ' specific ' differences " {Growth and 

" And of course, into Blooded and Bloodless, though there 
are, as Aristotle points out, no popular names for these 



Form, p. 726;. The co-ordinates to which he refers 
are those of the Cartesian method, on which is based 
the theory of Transformations. By means of them 
it is possible to exhibit, say, the cannon-bones of the 
ox, the sheep, and the giraffe as strictly proportionate 
and successive deformations of one and the same form. 
These deformations can be either simple elongations, 
as in the instance just cited, or they may occur 
according to an oblique or a radial system of co- 
ordinates, etc." In this way, differences of " excess 
and defect " are reduced to the terminology of 
mathematics ; and it is especially interesting to 
notice this, as the phrase " excess and defect " itself 
had, in the Greek of Aristotle's time, a mathematical 
connexion. With it may be compared the well- 
known Platonic phrase, " the great and small." But 
this is not the place to enlarge upon such topics.^ 
ciassifica- To rctum to Aristotle's classification. We find 
^mrts! t^^^^ ^^ implements his preliminary outline in the 
following way : 

I. First, he treats of the parts which are found in 
many different groups of animals, and also those 
which are to be considered counterparts of each 
other in different groups. This corresponds to 
A (1) above. 

II. As he proceeds 'vvith this, he comes to the 
Viscera, which occur only in blooded animals." 
This provides a convenient point for embarking 
upon his second main division — corresponding 

* For details see D'Arcy Thompson, op. cit. eh. xvii. 

* The reader is referred to A. E. Taylor, " Forms and 
Numbers," in Mind, xxxv. 419 foil. ; xxxvi. 12 foil. ; D'Arcy 
Thompson, " Excess and Defect," in Mind, xxxviii. 43 foil. 

•^ By " viscera " Ar. means the blood-like ones only. 


to A (2) above — the parts common to a group 

of animals, and we have first : 

The Internal Parts of Blooded Animals. 

III. This is followed by — 

The hiiernal Parts of Bloodless Animals. Then, 

IV. The External Parts of Bloodless Animals. Then, 
V. The External Parts of Blooded Animals, 

which includes — 

(a) Vivipara. 
(6) Ovipara. 

(i) Serpents and Quadrupeds, 

(ii) Birds. 

(iii) Fishes. 
(c) Intermediate Creatures. 

References to exceptional instances, as to Man, 
corresponding to the division A (3) above, are of 
course to be found throughout the w^ork. 

Aristotle thus works out the main lines of his 
classification. And in each instance, where possible, 
he endeavours to assign the Cause, to name the 
purpose, which is responsible for the parts as he 
describes them. This corresponds to (B) above. 

And here Aristotle is forced to admit an apparent Necessity. 
addition to his scheme of Causes. The purpose, the 
good End, the final Cause, cannot always get a free 
hand. There is another Cause, Necessity. Aristotle 
takes great care to explain what is the nature of this 
Necessity (642 a 2 foil.). It is what he calls Necessity 
" ex hypothesi," or " conditional " Necessity, the sort 
of Necessity which is implied by any final Cause 
being what it is. If a piece of wood is to be split 
by an axe, the axe must ex hypothesi be hard and 
sharp, and that necessitates the use of bronze or 



iron in the making of it. The same sort of Necessity 
applies in the works of Nature, for the Hving body 
itself is an instrument. It is thus the final Cause 
which necessitates the various stages of the process 
of formation and the use of such and such material. 

Another kind of Necessity, however, makes its 
appearance in Natural objects, and that is " simple " 
Necessity. The mere presence of certain things in 
a living organism entails of necessity the presence of 
others (see 645 b 32, 677 a 17, b 22). Some results 
follow inevitably from the very nature of the material 
used. This " simple " Necessity can therefore be 
regarded as a reassertion of themselves by the 
motive and material Causes" as against the final 
Cause. Sometimes, however, even in circumstances 
where " simple " Necessity operates, Nature is able to 
use the resulting products to subserve a final Cause 
(663 b 22, 32, 677 a 15 ; see also the note on Residues, 
p. 32). Cf. Gen. An. (Loeb), Introd. §§ 6-9- 
Scheme of The following table will show at a glance the 
anima s. g^j^^j^^ q£ Animals as treated of by Aristotle in the 
De partibus : 

A. Blooded Animals 
Viviparous quadrupeds 

Oviparous quadrupeds 
and footless animals 
(reptiles and amphi- 



B. Bloodless Animals 

See De gen. an. 778 b 1. 




between the above classes 

between land and water 

between animals and 







between quadrupeds and 






Note on the Four Classes of Bloodless Animals. — 
These, in order of increasing softness, as noted 
above, are the following (I give the Greek term, its 
literal translation, and the term which I have used 
to translate it in this volume) : 

Ttt ivTOfxa insected animals Insects 

ra ocTTpaKoSep/xa shell-skinned animals Testacea 

TO. fjuxXaKoa-TpaKa soft -shelled animals Crustacea 

Ta jxaXaKLa Softies Cephalopods 

In using " Testacea " to translate rot oa-rpaKoBepixa 
(" the animals with earthenware skins "), I use 
it in the old-fashioned sense, so as to include a 
number of shelled invertebrates, comprising Gastero- 
pods, Lamellibranchs, and some Echinoderms. It 
does not refer to the Testacea of modern zoologists, 
by whom the term is applied to the Foraminifera 
which are shelled Protozoa. The word " Ostraco- 
derms " (a transliteration of Aristotle's word) is now 
given by zoologists to a group of primitive fossil 




Technical The following notes on some of the more difficult 
terms, ^j^^ important of the technical terms used by Aristotle 
in the De partihus will, I hope, help to explain my 
translation and also to give some indication of the 
background of Aristotle's thought. (A fuller account 
will be found in De Gen. An., Loeb edn.) 

Atrta, ** cause." 

I retain the traditional translation " cause," 
although perhaps in some contexts " reason " may 
be a closer rendering, but a variation in the English 
term might well produce more confusion than clarity. 
To know, says Aristotle, is to know by means of 
Causes (see Anal. post. 94< a 20). A thing is explained 
when you know its Causes. And a Cause is that 
which is responsible, in any of four senses, for a 
thing's existence. The four Causes, of which two 
are mentioned very near the beginning of the first 
book (639 b 11), are : 

(1) The Final Cause, the End or Object towards 
which a formative process advances, and ybr the 
sake of which it advances — the logos, the rational 

(2) The Motive (or Efficient) Cause, the agent which 
is responsible for having set the process in motion ; 
it is that by jvhich the thing is made. 

(3) The Formal Cause, or Form, which is responsible 
for the character of the course which the process 
follows (this also is described as the logos, ex- 
pressing what the thing is). 

(4) The Material Cause, or Matter, out of which the 
thing is made. 



It will be seen that the first three Causes tend 
naturally to coalesce under the aegis of the Formal 
Cause, in opposition to the fourth, the Material 
Cause, a contrast which is clearly put by Adam of 
St. Victor in one of his hymns : 

effectiva vel formalis 
causa Deiis, etjiiialis, 
sed nuviquam materia. 

Hence, of course, comes the regular contrast of 
" form " and " matter," in which, oddly enough, in 
modern usage the two terms have almost exchanged 
meanings. " Mere form," " empty form," in con- 
trast with " the real matter," are phrases which 
indicate a point of view very different from that of 
Aristotle. An equally drastic reversal of meaning 
has overtaken the term " substance," as contro- 
versies on " transubstantiation," and the existence 
of the word " unsubstantial " prove. " Cause " has 
certainly been more fortunate ; but its meaning has 
been narrowed down, so that " cause " now usually 
suggests the " efficient " cause only. At the same 
time, we allow ourselves a wider variety of " efficient " 
causes than Aristotle, and are more ready to admit 
actions and events or even series of actions and events. 
We have, in fact, applied Aristotle's precise termin- 
ology to the wider uses of everyday non-technical 
purposes. For Aristotle, the doctrine of the Four 
Causes provides an exhaustive and precise classifica- 
tion of the things which can be responsible for another 
thing's existence, and by the naming of them the 
thing can be completely accounted for. 

As an illustration the following will serve. 
Suppose the object to be explained is an oak. The 



chronological order of the Causes is different from 
their logical one. 

(i.) The Motive Cause : the parent oak which 
produced the acorn. 

(ii.) The Material Cause : the acorn and its nour- 

(iii.) The Formal Cause. The acorn as it grew 
into a tree followed a process of development 
which had the definite character proper to 

(iv.) The Final Cause : the end towards which 
the process advanced, the perfected oak-tree. 


There are several places in the De partibus where, 
rather than represent Aoyos by an inadequate or 
misleading word, I have transliterated it by logos. 
This serves the very useful purpose of reminding the 
reader that here is a term of very varied meanings, 
a term which brings into mind a number of correlated 
conceptions, of which one or another may be upper- 
most in a particular case. It is an assistance if we 
bear in mind that underlying the verb Aeyeu', as it 
is most frequently used, is the conception of rational 
utterance or expression, and the same is to be found 
^^-ith Aoyos, the noun derived from the same root. 
Aoyo9 can signify, simply, something spokeii or uttered ; 
or, with more prominence given to the rationality of 
the utterance, it can signify a rational explanation, 
expressive of a thing's nature, of the plan of it ; and 
from this come the further meanings of principle, or 
law, and also of definition, or formula, as expressing 


the structure or character of the object defined. 
(Note here the application of the term logos to the 
Final and Formal Causes, recorded in the foregoing 
note.) Another common meaning is seen especially 
in the use of the dative Aoyw {cf. the verb XoyL^n/xai 
and its noun) — bi/ reasoning, in thought, as opposed to 
fact or action, (See 640 a 32, Art is the Aoyos rov 
epyov 6 avev rrjs vX')]S ', at 64^6 b 2 we read of the 
Aoyos of a process of formation such as building, and 
the Aoyo9 of the house which is built ; at 678 a 35 
of the Aoyos which defines the essence of something, 
and at 695 b 19 of " the Aoyos of the essence." At 
639 b 15 the " Cause for the sake of which " — the 
Final Cause — is described as being a Aoyos.) 

Fei/ecrts, " formation," or " process of formation." 
T ly veaOaL, " to be formed," " to go through a process 
of formation." 

These are the translations which I normally use, 
as more appropriate in a biological treatise than 
" coming into being," and the like. 

The process of formation is of course closely con- 
nected in Aristotle's thought with the doctrine of the 
Four Causes. 

Fei-ecrts is a process which, at any rate in biology, 
results in the production of an actual object, a living 

Fo'ecris is also contrasted with ova-La and (^vo-ts" : the 
order of things, we are told, in the process of formation 
is the reverse of the order in reality. For example, 
the bricks and mortar exist for the sake of the house 

" Care should be taken not to regard 0uatj as meaning 
" the process of ^u'ea^ai." 

B 27, 


which is to be built out of them, but they and not it 
come first in the order of time and fact. Aristotle 
sums this up by saying that what comes last in the 
process comes first in " nature " (646 a 25). 

MopioVf " part." 

The term M'hich occurs in the title of the treatise 
and is traditionally rendered " part " includes more 
than is normally included in the English " part of 
the body." For instance, this would not normally 
be applied to blood, but the term fxopLov is applied 
by Aristotle to all the constituent substances of the 
body as well as to the limbs and organs. For him, 
blood is one of the ^<p(iiv fiopia (648 a 2 ; see also 
664 a 9 J 690 a 8). A striking instance of the use of 
fiopiov in this sense is the phrase ra ofxoio/xepq /xopia, 
which are the subject of the next following note. 

Ta 6p.oiojji€prj popia, " the uniform parts." 

Ta dvopoLOjieprj popta, " the non-uniform parts." 

Aristotle's application of the term popiov to both 
these classes emphasizes the inclusiveness of its 
meaning. As examples of the " uniform " parts he 
mentions (647 b 10) blood, serum, lard, suet, marrow, 
semen, bile, milk, flesh — these are soft and fluid** 
ones ; also bone, fish-spine, sinew, blood-vessel — 
these are hard and solid ones. Of " non-uniform " 
parts he gives as examples (640 b 20) face, hand, foot. 

The relation of the " uniform " parts to the " non- 
uniform " he describes as follows (647 b 22 foil.) : 

" For the meaning of " fluid " and " solid " see below, 
p. 32. 


(a) some of the uniform are the material out of 
which the non-uniform are made (i.e. each 
instrumental part is made out of bones, sinews, 
flesh, etc.) ; 

(6) some act as the nutriment of (a) ; 

(c) some are the residue of (6) — faeces, urine. 

It is not possible to equate the two classes with the 
later division into tissues and organs, since blood, 
for instance, though " uniform," is not a tissue ; the 
term " organs," however, corresponds closely with 
Aristotle's own description — to. opyaviKa fxcprj 
(647 b 23), " instrumental parts." 

The practical difference between the two classes 
is that each of the uniform parts has its o^vn definite 
character as a substance (in the modern sense), while 
each of the non-uniform parts has its own definite 
character as a conformation or organ. The heart is 
the only part which belongs to both classes (647 a 25 
foil.) : it consists of one uniform part only, namely, 
flesh ; but it also has essentially a definite configura- 
tion, and thus it is a non-uniform part. 

Three stages or " degrees of composition," so far 
as biology is concerned, are enumerated by Aristotle 
(at 646 a 13 foil.). What Aristotle seems to mean, 
though he has not expressed himself quite clearly, 
is that there are three stages involved in the com- 
position of compound bodies, namely, 

(1) the 8vvdfi€Ls (see following note) ; 

(2) the uniform parts ; 

(3) the non-uniform parts ; 

and finally, of course, out of the non-uniform parts 

(4) the animal itself is composed. 


We have thus : 

(1) the simplest sorts of matter ; 

(2) the simplest organic substances compounded 
out of the foregoing (having no definite size, 
shape, or structure) ; 

(3) the instrumental parts of the body constructed 
out of the foregoing (having definite size, shape, 
and structure) ; and 

(4) the organism as a whole, assembled out of the 

Note. — For a description of the way in which the 
term rb. ojiotoixeprj has caused confusion in the accounts 
of Anaxagoras's theories see Class. Qu., 1931, xxv. 34 

This is one of the most difl^cult terms to render in 

The specialized meaning of Swdfj.ei, " potenti- 
ally," as opposed to h'€pye[a, " actually," is so well 
known that there is no need to enlarge upon it here. 
Nor need I discuss the mathematical meaning of 
SvvafXL'i. Other meanings need some comment. 

(1) Avva/us was the old technical term for what 
were later to be called o-rotyera (elements). It 
appears in the writings of the Hippocratic corpus 
and in Plato's Timaeiis. The best example of its 
use in De partihus is at the beginning of Book II. 
(646 a 15). The list of Swd/jLeis included the sub- 
stances known as to vypoVf to g'>]p<'>y, to depfxoi', to 
ipyxpor, TO —iKpov, TO yXvKv, to Spipv, etc., etc. Only 
the first four of these were regarded by Aristotle as 


the material of compound bodies : all the " other 
differences," he says, are consequent upon these. 

The original meaning underlying this usage of the 
term seems to have been " strong substance of a 
particular character." This would be very appro- 
priate to TO SpLfxv, TO TTiKpov, ctc. (scc Uepl dp)(^aLr]S 
h]TpLKris). There is no notion here of the substance 
kavi?ig power in the sense of power to affect an 
external body in a particular way. (This meaning 
developed later.) If any effect did result, it would 
be described simply as the presence of the strong 
substance, and the remedy for it was to " concoct " 
the strong substance or otherwise to bring it into 
a harmless condition by " blending " it with other 

(2) As each of the substances known as Sui/a/xei? 
has its own peculiar character, sharply marked off 
from the others, the meaning of " peculiar and dis- 
tinctive character " was naturally associated with the 
term. This seems to be its meaning in 655 b 12 : 
e^ di'dyKrjs 8e ravra iravra yecoSr) koL a-repedv e;)(et r7)x/ 
(j)vcriV ottXov yap avrr] 8vvap.ts. Indeed, in this mean- 
ing, Svvaixis seems to be a slightly more emphatic 
version of cfivcri^, with which it is often used in con- 
junction (in Hippocrates, for instance), or in a parallel 
May as in the passage just cited. Compare also 
651 b 21, where the marrow is asserted to be aJ'/xards 
Tis cjivcTL's, not, as some suppose, r^js yovrjs onvepiiaTiKr] 
Svvaiiis. Other instances of this use of St'i^a/xis will 
be found in De partibiis. 

(3) From this usage it is not far to the idiomatic, 
pleonastic usage, e.g. : 

678 a 13 7; TO)V €vrepoiv Syvajxts almost = Ta evrepa. 
682 h 15 rj TWV TTTipUJV BvvajMLS, 



657 a 4 i) Ttuv fxvKT/jpiDV 8vvajJ.L<s 8t<^ir>ys. 
This is paralleled by a similar usage of ^vo-ts X 

663 a 34> ->) roiv Kepdrayv cfiV(TLS. 
676 b 11 •>} Twv kvTepuiv cfiVcrLS. 

(Other references for Svvafxis : 640 a 24, 646 a 14, 
b 17, 650 a 5, 651 b 21, 652 b 8, 12, 653 a 2, 655 b 12, 
658 b 34. See further Gen. An., Loeb edn., Introd. 
§§ 23 ff.). 

To vypov KOi rh ^y)p6v, " fluid substance and solid 
substance," " the fluid and the soUd." 

These are two of the Svi'a/xets. 

Following Ogle, I use these renderings as being 
more in conformity with the definitions given by 
Aristotle than " the moist and the dry," which have 
often been used. Actually neither pair of Enghsh 
words quite expresses the Greek. Aristotle's de- 
finition of them (at De gen. et corr. 329 b 30) is this : 

** vypov is that which is not limited by any hmit of 
its own but can be readily limited, ^i^pov is that 
which is readily limited by a limit of its o^\'n but can 
with difficulty be limited " — i.e. of course by a limit 
imposed from without. 

He discusses the various senses in which these 
terms are used at 649 b 9 following. 

Ile/otTTw/za, " residue." 

This term I have translated throughout ** residue,* 


as being more literal and at the same time less mis- 
leading than " excrement." " Surplus " would have 
been even better if the word had been a little more 

" Residue " is so called because it is that which is 
left over when the living organism, by acting upon 
the nutriment which it has taken, has provided itself 
^vith a sufficient supply for its upkeep. Some of the 
surplus will be useless material contained in the food 
from the outset, or else has been produced during 
the process of reducing the food into a condition 
suitable for its purposes in the body. The useless 
residues include the excrements. In order to appreci- 
ate the status of the useful residues the outlines of 
the processes through which the food passes must be 
kept clearly in mind. Briefly, then, the food is 
masticated in the mouth, then passed on to the 
stomach and then the heart, where it is concocted " 
by means of heat — in other words, it is turned into 
blood, which is the " ultimate nourishment " ; and 
this, when distributed into the blood-vessels, suppHes 
the body with nutrition. Generally, however, more 
blood is produced than is necessary for the actual 
upkeep of the body, and this surplus undergoes a 
further stage of concoction, and is used by Nature 
in various ways. Marrow is a residue ; so are semen, 
catamenia, milk. Sometimes, when nutrition is 
specially abundant, the surplus blood is concocted 
into fat (lard and suet). And some of the blood, 
reaching the extremities of the vessels in which it 
travels, makes its way out in the form of nails, claws, 
or hair. The Aristotelian doctrine of residues came 
down to Shakespeare, as is shown by the passage 

*• See page 34. 



in Hamlet (iii. iv.) where the Queen says to Hamlet : 

Your bedded haire, like life in excrements, 
Start up, and stand an end. 

This theory, as applied to hair, is expounded by 
Aristotle at 658 b 14 following, and modern biochemists 
have reason for believing that some pigmentation in 
animals, such as the black melanin of mammalian 
hair, or the yellow xanthopterine of the butterfly's 
wing, is physiologically a form of excretion. 

" Concoct," ** concoction." 

These terms, which have already appeared in 
these notes, are used to translate TrecrcreLv, -n-eij/is. The 
Greek words are the same as those employed to 
denote the process of ripening or maturing of fruit, 
corn, and the like by means of heat — also that of 
baking and cooking. 

Terms sometimes associated ^\ith these are fxera/SoXy 
and jjnTa/SdWeLv. For example, at 650 a 5 we read 
that TTci/'ts and [jteraftoXy take place Slo. t7]s tov dipfxov 
8vv(tij.€0)<i ; and at 651 b 26, as the creatures grow 
and get " matured," the parts /xera/^aAAei their 
colour, and so do the viscera. 

"irvxrj, " Soul." 

The English word " Soul," as will be seen, over- 
emphasizes, when compared with ifi'X'h certain 
aspects of the Greek term, but it is by far the most 
convenient rendering, and I have used it in pre- 
ference to " hfe " or " vital principle." 

It will be useful to have an outline of Aristotle's 
general doctrine about Soul. 

The different " parts " or " faculties " of Soul can 


be arranged in a series in a definite order, so that the 
possession of any one of them implies the possession 
of all those which precede it in the list : 

(1) nutritive Soul in all plants 

(2) sentient Soul in all animals 

(3) appetitive Soul V • ^ 
)A 1 A.- c 1 [in some animals 

(4) locomotive boul j 

(5) rational Soul in man only 

At 641 a 23 Aristotle speaks of " parts " of the 
Soul, and though he often uses this phrase, the 
description he prefers is " faculties." In the passage 
which follows (641 a 33 foil.) all except appetitive 
Soul are mentioned. Sentient Soul is mentioned 
again at 650 b 24, 667 b 23, 672 b 16. 

Aristotle raises the question whether it is the 
business of Natural science to deal with Soul in its 
entirety, and concludes that it is not necessary, since 
man is the only animal in which rational Soul is 
found. Thus it is only some part or parts of Soul, 
and not Soul in its entirety, which constitute animal 

In the passage 641 a 14 follo-\\ing, Aristotle takes 
for granted his doctrine about Soul, which is as 
follows (De anima, Book II.). Animate bodies, bodies 
" with Soul in them " (Jjxxl^vxff), are " concrete sub- 
stances " made up of matter and form. In this 
partnership, of course, the body is the matter and the 
Soul is the form. Thus Soul may be described as the 
" form " or " realization " (eVreAeyeta, " actuality ") 
of the animal {cf. Depart., loc. cit.). 

This statement, however, is elsewhere made more 
precise. It is possible to distinguish tfvo " realiza- 
tions " of an animal ; for an animal " has Soul in it " 

B 2 35' 


even when it is asleep, but its full activity is not 
evident until it is awake and about its business. We 
must call Soul, then, the " first realization " of the 
animal, its waking life its " second realization.'* 
This distinction does not concern us in the De partibus. 
But an expansion of the definition is not irrelevant. 
Aristotle states that the Soul is the first realization 
of a body furnished with organs. The priority of 
Soul over body is emphasized in the passage just 
referred to (640 b 23—641 a 32), and in another in- 
teresting passage (687 a 8 foil.) Aristotle maintains 
that man has hands because he is the most intelli- 
gent animal, and not, as some have said, the most 
intelligent animal because he has hands. 

With this is connected the question whether the 
Soul is independent of the body ; though it is not 
raised in De partibus. As we have seen already, a 
^wov is a single concrete entity made up of Soul and 
body, i.e. a certain form implanted in certain matter. 
The matter can exist, for it did exist, apart from the 
form ; and as the form that is implanted in all the 
individuals of a species is one and the same form, 
clearly it can exist apart from any one individual's 
matter — though of course its existence is not in- 
dependent of all the individuals' matter. Further- 
more, the form — the Soul — requires matter of a 
particular kind : not any sort of matter will do. 
From these considerations two conclusions seem to 
follow : (1) that transmigration is impossible : a 
human Soul cannot function in a hyena's body, any 
more than the carpenter's art can be executed by 
means of musical instruments ; (2) the Soul cannot 
function without a body at all ; cannot, we may say, 
exist (4.14- a 19). 



So far, so good. But Aristotle is not satisfied. 
He feels the Soul is more than that. He finds a 
loophole. There may be some " part " of Soul (the 
rational part) which is not the " realization " of any 
body. The Soul, besides being the form, the formal 
Cause, of the body, is also its final Cause, and not 
only that, but the motive Cause too of all the changes 
originated in the body (De anima 415 b 7-28), for, as 
we saw (p. 25), the three non-material Causes tend 
to coalesce into one. This independent " part " of 
Soul " comes into the body from without " (see De 
gen. an. 736 b 25 foil.) and continues to exist after 
the death of the body (see De anima 413 a 6, b 24 foil., 
430 a 22, etc.). All this, however, raises problems 
not touched upon in De partihus ; indeed Aristotle 
himself offers no solution of them. 

^^X^i Kpacrts, aTrd/cptcri?, crvvTr]^is. 

I have indicated above, in the note on SvvafXL?, 
some of the older (Hippocratic) medical terminology 
of which traces are to be found in the De partihus. 
There is no room for an adequate discussion of such 
terms and theories, and the following bare references 
must suffice. 

In the Hippocratic treatise Tiepl Siacri^s the theory 
is put forward that the human organism, body and 
Soul alike, is composed of fire and water (which 
really consist of " the hot," " the sohd," " the cold," 
and " the fluid ") — the function of fire being to cause 
motion, of M'ater to provide nourishment. In ch. 35 
we have a hst of the different varieties of Blend 
(KprjcTLSf (rvyKpi](TLs) of fire and water which may be 



found in the Soul in different individuals, and upon 
the Blend its health and sensitivity ^ depend. 

With these statements may be compared the 
following passages in De partihus : 

652 b 8 Some, says Aristotle, maintain that the 

Soul is fiie ; but it is better to say 
that it subsists in some such material. 
** The hot " is indeed the most ser- 
viceable material for the functions 
which the Soul has to perform, and 
these include nourishing and causing 

647 b 30 foil. Here is a reference to the different 
varieties of blood, and Aristotle tells 
us which sort of blood is aladi^TiKM-epov 
and which animals are on that account 
(fipovtiuoTepa {cf. 650 b 24 and 686 b 28). 
The phrase ttt/xaro? K^ao-i? is actually 
used at 686 a 9- (Cf. also 650 b 29, the 
Kpaa-Ls in the heart ; 652 b 35, the parts 
in the head are colder than the cri'/x- 
fierpos Kpaa-LS ; 669 a 11, the KpacTLS 
of the body ; 673 b 26, its €VKpa<TLa.) 

The term (tvitt]^is, which occurs frequently in the 
liepl Si(u't//9, is found only once in the De partibus 
at 677 a 14 — bile is said to be a residue or irvvTi-j^is. 
Properly speaking, crri'T/y^ts^ is the term applicable to 
the " colliquescence " or decay of the parts of the body 
themselves. {Cf. a-vvryj-y/xa at De gen. an. 724 b 26 
foil. ; also (Tvi'T-)]^iSy 456 b 3 1; cf. also Piatt's note 
at the end of his translation of De gen. an. , on 724 b 27.) 
The effect of the colliquescence is to produce an 

• The adjective used is (f)p6vifios. 


unhealthy a-oKpicn^ (abscession) — a very common 
term in Ilept Suxlti]^ (see chh. 58 foil, throughout). 
It occurs twice in De pariibus. In both places it is 
used of a Tzepl-rMiJxi. At 690 a 9 the surplus earthy 
matter diroKpuTiv Xapf^av^i , and forms a continuous 
nail or hoof. At 681 b S5 Aristotle speaks of the 
place where the (r-eppo-iKij or the TrepLTTOjpo.nK-q 
d-oKpiCTLs is effected ; and here d-oKpta-ts seems to 
mean simply " act of excretion." The meaning of 
the term seems both here and in Hippocrates to be 
specially associated with 7reptTTw//a-a, either useful 
ones, or useless and even harmful ones. A great 
deal of Ilept SiaiT/;? is taken up with suggestions for 
getting rid of harmful diroKpicreLS. 

The meaning of d-oKpLan^ is therefore wider than 
" excretion " or " secretion," as used in their present 
usual sense, though these are included among its 

Tb p^kkov Kal rJTTov, " the more and less," see 
above, p. 19, and Gen. An. (Loeb), Introd. §§ 70 ff. 

Translations of Aristotle's Zoology 

The history of the translation of Aristotle's works Transia- 
begins with the Nestorian Christians of Asia Minor, Aristotle's 
who were familiar with the Greek language as their zoological 
service-books were written in it, and before the 
coming of the Arabs they had translated some of the 
works of Aristotle and Galen into Syriac. Before 


435, Ibas, who in that year was made Bishop of 
Edessa, had translated into Syriac the commentaries 
of Theodore on the works of Aristotle. Jacob, one 
of Ibas's successors at Edessa (d. 708), translated the 
Categories into Syriac, but a much earlier version had 
been made by Sergios of Resh 'Aina (d. 536), who 
had studied Greek at Alexandria. In 765 the Nes- 
torian physician Georgios was summoned to Bagdad 
by the Caliph, and translated numerous Greek words 
into Arabic for him. By the beginning of the ninth 
century, translation was in full swing at Bagdad, 
under the Caliphate of al-Mamun (813-833), son of 
Harun-al-Rashid. The first leader of this school 
of translators was the physician Ibn al-Batriq, who 
translated the Historia animalium, the De partibus 
animalium, and the De generatione animalium into 

But it was through southern Italy, Sicily and Spain 
that the transmission of Aristotle's works from the 
Arabic into Latin was effected. Messina had been 
recovered from the Saracens by 1060, and the whole 
of Sicily was freed by 1091. Under the Norman 
kings, Greeks, Saracens and Latins hved together 
in one community, and the court was the meeting- 
ground for eminent persons of all nations and 
languages. The reconquest of Spain had begun in 
the eighth century, so that here also an opportunity 
offered for making the works of Greek science 
available in Latin. Archbishop Raymond of Toledo 
(1126-1151) and Bishop Michael of Tarazona (1119- 
1151) were the patrons of the translators, who made 
Toledo the centre of their activity. One of these 
was Michael Scot. 

There is in existence an Arabic translation of 



the zoological works, of which there is a ms. in 
the British Museum." It is probable that this is the 
translation made by Ibn al-Batriq, and that this 
Arabic version is the original from which Michael 
Scot made his Latin translation at Toledo.^ Michael 
was, among his other accomplishments, astrologer to 
Frederick II., King of Sicily, at his court at Palermo, 
and before 1217 he had reached Toledo and was at 
work there on his translations from the Arabic. His 
De a7iimaUhus (a translation of the zoological works in 
nineteen books) is one of his earliest works, and two 
Mss. of it ^ contain a note which gives a later limit 
of 1220 for the work. Other evidence'^ establishes 
that it was certainly finished before 1217, and it may 
even be placed in the first decade of the century. 
It is probable that Michael had as collaborator one 
Andrew, canon of Palencia, formerly a Jew. One 
of the earliest to make use of Michael's transla- 
tions was Robert Grosseteste,^ Bishop of Lincoln 
(d. 1253), one of the leading Aristotelian scholars 
of the time, who quotes from Michael's version of 

« B.M.Add. 7511 (13th-14th century). Th^s is the ms. 
referred to by Steinschneider, Die arabischen Uhersetzungen 
p. 64, as B.^I. 437. I have seen this ms. 

** Judging from the passages which Dr. R. Levy kindly 
read for me in the Arabic ms., the Latin version is a close 
translation from it. Also, the contents-preface wliich is found 
prefixed to Michael Scot's translation corresponds exactly 
with the preface which precedes the Arabic version in this 
MS. (see the B.M. catalogue, Catalogus codicum manuscrip- 
torum orientaliuyn, p. 215). 

•^ One of them is ms. Caius 109, in the library of Gonville 
and Caius College, Cambridge. It is of the thirteenth 

^ See S. D. Wingate, The Medieval Latin Versions, p. 75. 

• Born at Stradbroke, Suffolk. A Franciscan. 



De gejieratione.^ The De animalihus also formed the 
basis of a commentary in twenty-six books by 
Albertus Magnus.'' This was probably written soon 
after the middle of the thirteenth century. Except 
for the portions which appear in Albertus 's com- 
mentary, and the earlier part of the first chapter," 
Michael's version has never been printed in extenso. 
Michael died in or before 1235, and is reputed to 
have been buried, as he was born, in the lowlands of 

About the same time, at the request of a pupil of 
Albertus, St. Thomas Aquinas (1227-1274), who re- 
quired more accurate versions for his commentaries 
on the works of Aristotle, new translations, direct 
from the Greek, were being undertaken by William 
of Moerbeke.^ William was born about 1215. He 
became a Dominican, was confessor to Popes Clement 
IV. and Gregory X., and was Archbishop of Corinth. 
He acted as Greek secretary at the Council of Lyons 
in 1274<. He died in 1286. The earliest dated trans- 
lation made by him is one of the De partibus animalium. 
The date 1260 occurs in a ms. of it at Florence (Fae- 
sulani 168), which also contains Hist, an.^ De progressu 
an., and De gen. an. This translation was made at 

Among later Latin translators of the zoological 

" According to Roger Bacon, Michael appeared at Oxford 
in 1230, bringing with him the works of Aristotle in natural 
history and mathematics. 

" Ed. 'princepsy Rome, 1478 ; latest ed., H. Stadler, 

« 639 a 1—640 a 20, printed by G. Furlani in Rivista 
degli Studi Orientali, ix. (1922), pp. 246-249. 

** A small town south of Ghent on the borders of Flanders 
and Brabant. 


works the names of two Greeks must be mentioned. 
George of Trebizond (Trapezuntius), who was born 
in Crete in 1395, visited Italy between 1430 and 
1438, and was secretary to the humanist Pope 
Nicholas V., an ardent Aristotelian. George's work, 
however, was hurried and not over-exact, and he, 
together with his predecessors, was superseded by 
his contemporary Theodore of Gaza, who was born 
in Thessalonica about 1400, and was professor of 
Greek at Ferrara in 1447. In 1450 Theodore was 
invited by the Pope to go to Rome to make Latin 
versions of Aristotle and other Greek authors. His 
translation of the zoological works," dedicated to the 
Pope, Sixtus IV., soon became the standard version, 
and it is printed in the Berhn edition of Aristotle. 

Translations of the De gen. were made by Augus- 
tinus Niphus, of the University of Padua (1473-1546), 
and of the De gen. and De incessu by Peter Alcyonius 
(Venice, 1487-1527). The De gen. was also translated 
by Andronicus Callixtus of Byzantium (d. 1478). 
With the later Latin versions we need not here 
concern ourselves, but something must be said of 
the scientific workers who were inspired by Aristotle, 
and of the translations into modern languages. 

The Renaissance biologists show unmistakably the Aristotle's 
difference in quaUty which there is between Aristotle's successors. 
physics and his biology. Hieronimo Fabrizio of 
Acquapendente (1537-1619) knew and admired 
Aristotle's work on embryology, and what is more, 
himself carried out further important observations 
on the same subject. His brilliant successor, William 
Harvey (1578^1657), was a student of Aristotle, and 

" In eighteen books, excluding the spurious tenth book of 
the Historia animalium, 



much of his inspiration came from that source. 
William Harvey was the first to make any substantial 
advance in embryology since Aristotle himself. But 
this is more appropriate to the De generatione than 
to the De partihus. In other departments of study, 
however, during the seventeenth century, the 
authority of Aristotle and the scholastic doctrine 
with Mhich he was identified were being combated 
in the name of freedom, and thus it came about that 
the zoological works also, which had been brought 
to light by the dark ages, were allowed to pass back 
into oblivion by the age of enlightenment. They were 
not rediscovered until the end of the eighteenth 
century by Cuvier (1769-1832) and Saint-Hilaire 
(1805-1895) in the nineteenth. 

Modern Editions 

1. The Berlin edition of Aristotle, by Immanuel Bekker. 

Vol. i. (pp. 639-697) includes P.A. Berlin, 1831. 
1a. The Oxford edition (a reprint of the preceding). Vol. v. 
includes P.A. Oxford, 1837. 

2. One-volume edition of Aristotle's works, by C. H. Weise 

(pre-Bekker text). Leipzig, 1843. 
8. The Leipzig edition. Vol. v. contains P. A., edited and 
translated into German by A. von Frantzius. Leip- 
zig, 1853. 

4. The Didot edition. Vol. iii. includes P.A. Edited by 

Bussemaker. Paris, 1854. 

5. The Teubner edition. Edited by Bernhardt Langkavel. 

Leipzig, 1868. 

6. The Bude edition. Edited by Pierre Louis. With a 

French translation and notes. Paris, 1956. 

Translations without Text 

7. Thomas Taylor. English translation of Aristotle in ten 


volumes. Vol. vi. includes P.A. (pp. 3-163). London, 

8. F. N. Titze. German translation of Book I. In his 

Aristoteles ilher die wissenschaftliche Beliandlungsart 
der Naturkunde. Prague, 1819. 

9. Anton Karsch. German translation. Stuttgart, 1855 

(second ed., Berlin, 1911). 

10. William Ogle. English translation, with notes. Lon- 

don, 1882. 

1 1 . J. Barthelemy-Saint-Hilaire. French translation, with 

notes. Paris, 1885. 

11. William Ogle. English translation, with notes (a re- 

vision of No. 10). Oxford 1911. 

12. Francisco Gallach Pales. Aristoteles: Obras com- 

pletas. Vol. X contains De partibus and De incessu 
animalium. Spanish translation, without notes. Vol. 
Ixii. of Nueva Biblioteca Filosofica. Madrid, 1932. 

Langkavel reproduces almost verbatim the Berlin 
text, together with Bekker's apparatus, to w^hich a 
great deal of other matter has been added, including 
some of Bekker's ms. notes in his copy of Erasmus's 
edition, and some corrected reports of the readings 
of the MS. E, which Langkavel himself inspected. 
Also, there are some emendations proposed by 

Any English translator must stand very much 
indebted to the work of William Ogle, whose trans- 
lation, originally published in 1882, was revised by 
its author and republished in the Oxford series of 
translations of Aristotle in 1911- It is not possible 
to overrate the care and exactness with which this 
piece of work was executed. I should like here to 
acknowledge my own indebtedness to it, and I have 
had its accuracy as a model before me. With re- 
gard to style, it will be seen that I have aimed at pro- 
ducing something rather different from Ogle's version. 



The Text 

The M3S. The manuscript authorities cited by Bekker for the 
De partihus will be found on p. 50. 

The dates of some of the mss. as given by different 
scholars vary considerably : for details I refer the 
reader to the various catalogues, and also to L. Ditt- 
meyer's edition of Hist. an. (Leipzig, 1907) and W. W. 
Jaeger's edition of De an. motu, etc. (Leipzig, 1913). 
storation I have relied upon the apparatus of Bekker and 
the text. Langkavel for the readings of the Greek mss., except 
for those of Z, the oldest parts of which I have collated 
from photostats " ; and at several places I have in- 
spected the MS. itself. In some places (e.g. QQo b 17, 
685 a 2, 16) I found the reading had been defectively 
reported. It is clear that a more reliable collation of 
the chief mss. of De partihus is clearly needed. From 
a different source I have attempted to restore intelligi- 
bility to several corrupt passages with the aid of the 
Arabic version and the Latin version of Michael 
Scot, which represent an earlier stage of the Aristo- 
telian text than our Greek mss. Among the passages 
dealt with in this way are the passage at Q5^ b 14 
following, which has been dislocated by glosses and 
phrases imported from elsewhere, and the remark- 
able passage about the structure of the Cephalopods 
at 684 b 22 following, where considerable havoc has 
been done to the text by references to a diagram 
which were inserted at some period between the 
date of the ms. from which the Arabic version was 
made and that of the archetype of all our present 
Greek mss. I have been able to restore this passage, 
though not always the actual Greek words, by refer- 
ence to the Arabic version and Michael Scot's Latin 

" See additional note on p. 434. 


translation made from it. Dr. Reuben Levy has 
most kindly read this passage for me in the 13th-14th 
century Arabic ms. in the British Museum, Add. 7511. 
For these two passages, and for a good many other 
suspected places, I have consulted all the known mss. 
of Michael Scot's version which are to be found in 
this country. They are (excluding mss. which contain 
merely abridgements or extracts) : 

Cambridge, Gonville and Caius College 109 
„ University Library li. 3. 16 

Dd. 4. 30 
Oxford, Merton College 278 
„ Balliol College 252 
London, British Museum Royal 12. C. XV 
Harl. 4970« 

All these are of the thirteenth or fourteenth 

I have inspected at test places the following three 
MSS. of William of Moerbeke's version : 

Oxford, Merton College 270 
„ 271 

BalUol College 250 

William's translation was made from a ms. or mss. 
which had already been infected by the corruptions 
found in the Greek mss. which exist to-day. 

I should like here to express my thanks to the 
Librarians who so kindly made arrangements for me 
to inspect the mss. under their care. 

Where I have accepted the reading of the Berlin Scope of 
edition, I have not n;iven any record of the ms. vari- cr/JIcS,"* 
ants. These are to be found in the apparatus criticus 
of that edition and of Langkavel's edition. 

• So far as I know, this ms. has not been mentioned in any 
of the published lists of mss. of Michael Scot's De animalibus. 



I have endeavoured, except in the passage 
691 b 28 to 695 a 22 in the fourth Book, to record 
all places where I have departed from the text of 
the Berlin edition, and I have given the source of 
the reading which I have adopted. Where Bekker 
himself introduced a reading different from that of 
the Mss., this is attributed to him by name. 
Punctua- I have not recorded all of the many passages in 
^°"' which I have corrected the punctuation. The text 
has been reparagraphed throughout. 

Short bibiio- The following list includes authorities for state- 
^*^ ^' ments made in the Introduction, and books which 
the student of the Aristotelian zoological works and 
their history will find useful : 

C. H. Haskins, Studies in the History of Medieval Science^ 

ed. 2, Cambridge, Mass., 1927. 
W. Jaeger, Aristotle (English tr. by R. Robinson), Oxford, 

L. Leclerc, Histoire de la medecine arabe, Paris, 1876. 
T. E. Lones, Aristotle's Researches in Natural Science^ 

London, 1912. 
W. D. Ross, Aristotle, London, 1930. 

J. E. Sandys, A History of Classical Scholarship, Cam- 
bridge, 1908-1921. 
C. Singer, Studies in the History and Method of Science, 

Oxford, 1921. 
C. Singer, Greek Biology and Greek Medicine, Oxford, 1922. 
M. Steinsclineider, Die arahischen Uhersetzungen aus dem 

Griechischen (Beiheft XII. zum Centralblatt fiir 

Bibliotliekswesen), Leipzig, 1893. 
M. Steinschneider, Die europdischen Uhersetzungen aus dein 

Arahischen, in Sitzungsberichte d. kais. Akad. der Wiss., 

cxlix., Vienna, 1905. 
D'Arcy W. Thompson, Growth and Form, Cambridge, 

1917 (new ed., 1942). 


D'Arcy W. Thompson, Essay on " Natural Science " in 
The Legacy of Greece, Oxford, 1924. 

S. D. Wingate, The Medieval Latin Versions of the Aristo- 
telian Scientific Corpus, London, 1031. 

F. Wiistenfeld, Die Ubersetzungen arabischer Werke in das 
Lateinische, in Abhandlungen der k, Gesell. d. Wiss. 
zu Gottingen, xxii., 1877. 


It is a great pleasure to acknowledge here the help 
which I have received from many friends at Cambridge, 
not only by way of reading typescript and proof and 
by discussion, but also by the interest which they 
have shown in the work and by their continuous 
encouragement. The following have read the trans- 
lation either in whole or in part : Prof. F. M. Corn- 
ford, Professor of Ancient Philosophy ; Dr. F. H. A. 
Marshall, Reader in Agricultural Physiology (w^ho has 
also kindly wTitten the Forew^ord to this volume), 
and Dr. Joseph Needham, Reader in Biochemistry. 
I am under a particular obligation to my colleague 
Mr. H. Rackham, who has read the whole translation 
both in typescript and in proof. I am indebted 
to Dr. Sydney Smith and a number of other friends 
for their kindness in discussing various points and 
for reading certain passages. Dr. Reuben Levy, 
Professor of Persian, has kindly read for me some 
passages in the Arabic translation of the zoological 
works. To all of these gentlemen, without whose 
aid the work could not have been carried through, 
I record my sincerest thanks. 

The present (third) edition has again been revised. 

A. L. P. 

July nth 195;^ 



E Parisinus regius 1853 (see p. 434) 

Y Vaticanus graecus 261 

Z Oxoniensis Coll. Corp. Chr. W.A. 2. 7 (see p. 434) 

U Vaticanus 260 

P Vaticanus graecus 1339 

S Laurentianus Mediceus 81. 1 

Q Marcianus 200 

b Parisinus 1859 

m Parisinus 1921 

2 Michael Scot's Latin version, from my 

own transcription, 
vulg. The usual reading, as in the Berlin 

Langkavel Emendations proposed by Langkavel in 

his edition. 
Ogle Emendations proposed by WiUiam Ogle 

in footnotes to his translation. 
Piatt Emendations proposed by Arthur Piatt, 

either (a) in " Notes on Aristotle," in 
Journal of Philology, 1913, xxxii. 292 
following, or (6) recorded by Ogle in 
footnotes to his translation. 
^ r J \ (Suggestions in private communications 
Corntord L^ ^^ ^^^^^ Professor Cornford and Mr. 
RackhamI (^^.i^ham. 

Th(urot) Ch. Thurot, in Rev. Arch., 1867.« 
Peck Emendations proposed by myself. 

" Of over 100 textual points, many being of minor import- 
ance, raised by Th., about a third had been dealt with in my 
first edition (before Th.'s work came to my notice), some of 
them more fully, by other scholars or myself. Some of Th.'s 
other suggestions have been adopted in this edition. 

The maister Cooke was called Concoction. 

Spenser, Faerie Queen 


9 a Ilept irdoav Becjopiav re /cat [ledoSov, ofioicos 
raTTeivorepav re Kal TLfXicorepav, Svo (jiaivovrai 
rpoTTOL rrj? e^ecos elvai, (x)V ttjv fikv emorrnjuqv 
rod TTpdypLaros KaXcos ex^i TTpooayopeveiv, rrjv 8* 
5 otov TTaiheiav rivd. TTeTTaiSevfievov yap ion Kara 
rpoTTov TO hvvaoOai KpZvai evaro-xtos tl KaXcijs -^ firj 
KaXcjs dTToSlSajGLV 6 Xeyojv. tolovtov yap S-q rtva 
Kal Tov oXwg TreTTaiSevfievov olofjied^ elvai, /cat to 
TTeTTaihevudai to SvvaoOaL TTOielv to elpr^pLevov. 
TrXrjv TOVTOV [xev Trepl TrdvTCOV cLs el-nelv KpiTiKov 

10 Ttva,oixev elvai eva tov dpidfxov oVra, tov 8e 
77ept TLVos (j)VG€OJS d(f)OjpLapJvr]s' etrj yap dv Ttg 

€T€pOS TOV aVTOV TpOTTOV Tip elp'^jxlvCp SLaK€LfJL€VOS 
7T€pl fJLOpLOV^ (JJOTe SrjXoV OTL Kal TTJS 7T€pl (f)V<JlV 

iGTopias Set TLvds virdpx^^v opovs toiovtov^ Trpos 
ovs dva<f>epa>v a-TroSe^erat tov Tponov tcov Set/cvu- 




There are, as it seems, two ways in which a 
person may be competent in respect of any study or 
investigation, whether it be a noble one or a humble : 
he may have either what can rightly be called a 
scientific knowledge of the subject ; or he may have 
what is roughly described as an educated person's 
competence, and therefore be able to judge correctly 
which parts of an exposition are satisfactory and 
which are not. That, in fact, is the sort of person 
we take the " man of general education " to be ; his 
** education " consists in the abihty to do this. In 
this case, however, we expect to find in the one 
individual the ability to judge of almost all subjects, 
whereas in the other case the abihty is confined to 
some special science ; for of course it is possible to 
possess this abihty for a limited field only. Hence 
it is clear that in the investigation of Nature, or 
Natural science, as in every other, there must first 
of all be certain defined rules by which the ac- 
ceptability of the method of exposition may be 
tested, apart from whether the statements made 


639 a ^ X 

15 jjidvcov, X^P^^ "^^^ '^^S' e;)(et rdXrjdes, etre ovroj? 

etre dXXoj?. Xeyco 8' olov iroTepov heZ Xafx^avovras 
[xiav eKdarrjv ovoiav Trepl ravrr]? hiopit,eiv Kad^ 

aVT'^V, olov 7T€pl dvdpwTTOV (jiVGeOJS ri XioVTOS T] 

Poos "^ Kal TLvos dXXov KaO" eKaarov npox^Lpil^o- 
pievovs, rj TO, KOivfj GvpLlSe^rjKora Trdoi Kara tl 
Koivov V7To9ep.€vov£-^oXXd yap vrrapx^i ravrd 
20 TToXXoZg yev€GLv irepois ovolv dXXrjXo^v, olov vrrvos, 
avaTTVorjy av^rjOLS, (jidiuis, Odvaros, Kal Trpos rov- 
roL? ooa roLavra rcov Xenrop^evajv Tradchv re Kal 
SiaOeoewv dS7]Xov yap Kal dSLopLorov ion Xeyeiv 

VVV 7T€pl TOVTOJV (f)aV€p6v 8' OTL Kal KaTOL fJi€p09 

pikv XeyovTGS irepl ttoAAojv ipovp.€v TToXXdKis ravrd' 

25 Kal yap Ittttois Kal kvgI Kal dvdpojTTois VTrdpxei 

'rcjv elpr]pLivo)v eKaorov, wore idv Kad^ eKaorov rd 

ovpL^^^iqKora^ Xiy-Q ns, TroAAa/cts" dvayKaodrjoerai 

TTcpl rcov avrwv Xeyeiv, ooa ravrd p,ev VTrdpx^L rots' 

ctSet hia<f)€povGi rcov t^cpojv, avrd 8e pb-qhepiiav €X€l 

30 SLa(f)Opdv. erepa 8' lgojs iorlv oh GvpL^alvei rrjv 

639 b [X€v Karriyopiav €X€lv r7]v avrrjv Siacjiepeiv 8e rfj 

/car' etSos" 8ta<^o/)a, otov rj rcjv ^cucov rropeia' ov 

yap (f)aLV€raL fJLLa rev etSet- hiacjyepei yap rrrrjoig Kal 

vevGi? Kal ^dhiGi? Kal epiJjL?. 

Aid Set p.rj hiaXeXridivai ttojs eTTLGKeTTreov, Xeyo) 
6 8e TTorepov Koivfj Kard yevos TTpcjrov, eW vorepov 

^ TO avu^e^-qKora Ogle : tcDv avfi^e^rjKOTcov vulg. 



represent the truth or do not. I mean, for instance, 
should we take each single species severally by turn 
(such as Man, or Lion, or Ox, or whatever it may 
be), and define what we have to say about it, in and 
by itself ; or should we first establish as our basis the 
attributes that are common to all of them because 
of some common character which they possess ? — there 
being many attributes which are identical though 
they occur in many groups which differ among them- 
selves, e.g. sleep, respiration, growth, decay, death, 
together ^^^th those other remaining affections and 
conditions which are of a similar kind. I raise this, 
for at present discussion of these matters is an obscure 
business, lacking any definite scheme. However, 
thus much is plain, that even if we discuss them 
species by species, we shall be giving the same de- 
scriptions many times over for many different animals, 
since every one of the attributes I mentioned occurs 
in horses and dogs and human beings alike. Thus, 
if our description proceeds by taking the attributes 
for every species, we shall be obliged to describe the 
same ones many times over, namely, those Avhich 
although they occur in different species of animals are 
themselves identical and present no difference what- 
ever. \^ery likely, too, there are other attributes, 
which, though they come under the same general 
head, exhibit specific differences ; — for example, the 
locomotion of animals : of which there are plainly 
more species than one — e.g. flight, swimming, walk- 
ing, creeping. 

Therefore we must make up our minds about 
the method of our investigation and decide whether 
we will consider first what the whole group has in 



639 b 

TTepl T(x)v Ihiiov deojp-qreov, rj Kad^ e/cacrrov €v6v^, 

vvv yap ov Stco/otcrrat Trepl avrov, ovSe ye to vvv 

pi'ldriGopievov, olov TTorepov KaOdnep ol fJLadrjpLarLKol 

ra irepl ttjv aorpoXoyiav heiKvvovGiv, ovtoj Set Kal 

Tov (jyvGiKov TO. (jyaivofjieva TTpujTOV ra Trepl ra t,cpa 

10 Oecoprjoavra /cat ra fJiepr] ra Trepl eKaarov, erret^' 
OVTOJ Xeyeiv to 8ta Tt kol ras alrlag, rj dXXcos ttcos. 
TTpog Se TouTOt?, irrel rrXeiovs opcofjiev alrias Trepl 
rrjv yeveohv Trjv (f)vaLKrjv, otov nqv 6^ ov eveKa Kal 
TTjv oOev Tj ap)(r] ttjs KLvqaecog, hiopiareov Kal 
TTepl TOVTOJV, TToia TrpcoTT) Kal Sevrepa TTe(j>VKev. 

15 (jyaiverai he vpcarr] tjv XeyojJiev eveKa tlvos' Xoyo? 
yap ovTog, o.pxV ^' ^ Aoyo? ofJLOLOJs ev re toZs 
Kara Te-xyT]^ Kal ev TOt? ^uoet GVveorrjKOGiv . tj 
yap rfj hiavoia tj rfj acGOrjGei opiGapbevos 6 jjiev 
larpos TTjv vyieiav 6 8' oiKohofxos ttjv ot/ctav, 
aTToStSoaat rovs Xoyovs Kal rag alrias ov ttoiovglv 
eKOLGTOV, Kal 8toTt TTOiTjTeov OVTCJS - jjidXXov 8' 

20 eaTt TO ov eveKa Kal to KaXov ev Totg ttjs (j)VGea)s 
epyois ri ev rols ttj? rex^qs. to 8* ef dvayK-qg 
OV TTaGiv vTTapx^L ToXg KaTOi (f)VGLV ofxoLcos, els 

" This point is resumed and decided below, 644 a 23 if., 
6io b 2 ff. 

* " Causes." See Introduction, pp. 24 ff. 

* " Formation." See Introduction, pp. 27 f. 
^ i.e. the " final " cause. 

* i.e. the " motive " or " efficient " cause. 

f See Introduction, pp. 26 f. ' Cf. 64o a 24. 



common, and afterwards the specific peculiarities ; 
or begin straightway with the particular species.** 
Hitherto this has not been definitely settled. And 
there is a further point which has not yet been 
decided : should the student of Nature follow the 
same sort of procedure as the mathematician follows 
in his astronomical expositions — that is to say, 
should he consider first of all the phenomena which 
occur in animals, and the parts of each of them, and 
having done that go on to state the reasons and the 
causes ; or should he follow some other procedure ? 
Furthermore, we see that there are more causes^ 
than one concerned in the formation^ of natural 
things : there is the Cause for the sake of which the 
thing is formed,^ and the Cause to which the begin- 
?u?i£r of the motioji is due.^ Therefore another point 
for us to decide is which of these two Causes stands 
first and which comes second. Clearly the first is 
that which we call the " Final " Cause — that for the 
sake of which the thing is formed — since that is 
the logos f of the thing — its rational ground, and 
the logos is always the beginning for products of 
Nature as well as for those of Art. The physician 
or the builder sets before himself something quite 
definite — the one, health, apprehensible by the 
mind, the other, a house, apprehensible by the 
senses ; and once he has got this, each of them 
can tell you the causes and the rational grounds 
for everything he does, and why it must be done 
as he does it. Yet the Final Cause (purpose) and the 
Good (Beautiful) ^ is more fully present in the works 
of Nature than in the works of Art. And moreover 
the factor of Necessity is not present in all the 
works of Nature in a similar sense. Almost all 



639 b ^ 

o TTCLpajvraL Trdvres o^^^ov rovs Xoyovs avdyeiv, 

ov SteAojLtevot TToaa^oj? Aeyerat ro dvayKaXov. 
V7Tdp)(^ei he TO fxev OLTrXojs rots' ollSlols, to S* e^ 

25 VTToOecreoj? Kal toZs ev yeviaei Trdaiv wanep iv 
TOLS TexvaaToT? , olov oIklo, Kal tcov dXXcov otwovv 
TCJV TOLOVTOJv. dvdyKTj Se TOidvSe ttjv vXt]v vtt- 
dp^au el eGTai OLKia r) dXXo tl reAos" Kal yeveaOai 
T€ Kal KLvrjOrivai Set Tohe rrpcoTOV, etra ToSe, Kal 
TOVTOV Srj Tov Tporrov e(f)€^rjg f^^XP^ '^^^ TeXovs Kal 

30 ov eVe/ca ytVerat eKaoTov Kal eaTLV. cboravTCos Se 

640 a /cat eV TOLS (jivaei yivopievoi?. dAA* o Tpoiros Trjs 

diToSeL^ewg Kal Trjg dvdyKrj^ eTepos erri t€ ttjs 
(f)VGLKr]9 Kal Tcbv 6ea>p7]TiKa)v e7noT7]pL(A)V . {eipr]Tat 
S* iv eTepois rrepl tovtojv.) tj yap dpxr) toXs fxev to 
ov, rots' Se TO eGOfievov errel yap roiopS' euTlv tj 
6 vyieia tj 6 dvOpojiros, avdyKiq Toh^ elvai r) yeveoOai, 
dXX ovK errel toS^ eoTLv tj yeyovev, eKelvo i^ 

" " Absolute," i.e. simple or unconditional necessity, 
belongs to the " eternal things," such as the heavenly bodies 
or the eternal truths of mathematics. For further details 
see De gen. et corr. 337 b 14 if. 

" At Met. 1025 b ff. Aristotle makes a threefold classifica- 
tion of the sciences into (a) theoretical (contemplative), 
(6) practical, (c) productive. The result of (a) is knowledge 
only, of (6) knowledge and action, of (c) knowledge, action, 
and some article or product. The three " theoretical " 
sciences are theology {i.e. metaphysics), mathematics, and 
physics (natural science). In the present passage, however, 
Aristotle contrasts natural science with the " theoretical " 
sciences. This is because he is considering Nature as a 
craftsman whose craft or science belongs to the third class — 
the " productive " sciences. Our study of Nature's science 



philosophers endeavour to carry back their explana- 
tions to Necessity ; but they omit to distinguish the 
various meanings of Necessity. There is " absolute " 
Necessity,^ which belongs to the eternal things ; and 
there is " conditional " Necessity, which has to do 
with everything that is formed by the processes of 
Nature, as well as with the products of Art, such as 
houses and so forth. If a house, or any other End, 
is to be realized, it is necessary that such and such 
material shall be available ; one thing must first be 
formed, and set in motion, and then another thing ; 
and so on continually in the same manner up to the 
End, which is the Final Cause, for the sake of which 
every one of those things is formed and for which it 
exists. The things which are formed in Nature are 
in like case. Howbeit, the method of reasoning 
in Natural science and also the mode of Necessity 
itself is not the same as in the Theoretical sciences. 
(I have spoken of this matter in another treatise.^) 
They differ in the following way.'' In the Theoretical 
sciences, we begin with what already is ; but in 
Natural science ^Wth what is goi?ig to be : thus, w^e say, 
Because that which is going to be — health, perhaps, or 
man — has a certain character, therefore of necessity 
some particular thing, P, must be, or must be formed ; 
not, Because P is now, or has been formed, therefore 
the other thing (health, or man) of necessity is now 

may be a " theoretical " science, but Nature's science itself 
is " productive." 

" The reasoning process in a " theoretical " science, e.g. 
mathematics, begins, say, with A, and then deduces from it 
the consequences B, C, D. In a " productive " science, 
e.g. building, it begins with the house which is to be built, 
D, and works backwards through the preliminary stages 
which must be realized in order to produce the house, 
C, B, A. Cf. below, 640 a 16 ff. 

c 59 


640 a ^ 

avayKTjs iorlv ri earat. ouS' eariv els aihiov ovv 
aprrjaai rrjg rotavT'qs aTTohei^eats ttjv dvdyKrjv, 
iooT etVetv, eVet rdS' iarlv, on rdS' eoriv. 8t- 
wpiarai Se kol Trepl tovtojv iv irepois, koI ttolols 
V7Tap)(^€L KOI TToZa dvTLUTpe(f)eL Kal Sta rtV alriav. 

10 Aet 8e /XT^ XeXrjOevai Kal TTorepov TrpooriqKeL Xeyeiv, 
ojanep ol irporepov i-noiovvro rrjv decopiav, ttws 
GKaarov yiveodai 7Te(f)VKe fxdXXov 7) ttojs ecrrtv. 
ov yap TL jjLiKpov 8ia(f)ep€L rovro eKeivov. €olk€ 
o ivrevdev dpKreov elvai [Kaddirep Kal rrporepov 
€L7TOfiev, on TTpdJTov Ta cfyaivofMeva XrjTTreov Trepl 

15 eKaarov yivos, eW^ ovTa> ras" alrias tovtojv 
XeKTeov) Kal Trepl yeveoeojs' fidXXov yap raSe 
ovfi^aivei Kal Trepl ttjv olKoS6fji7]GLV eVet rotdvS' 
ecrrt to elSos ttjs olKias, t] Toiovh" IutIv rj oWia otl 
yiveTai ovtojs. rj yap yeveois eveKa ttjs ovoias 
eoTLV, aAA* ovx 'f) ovuia eveKa ttjs yeveGews . StoTrep 

20 'E/XTreSo/cATj? ovK opdcog eiprjKe Xeycov VTrdp^eiv 


yeveGei, otov Kal tt^v pd^iv ToiavTiqv ex€LV otl 
OTpa(f)evTos KaTa^d^jvai Gvve^r], dyvoojv TrpwTov p.ev 

^ ovviorav Piatt : avarav vulg. 

** Though of course this Necessity has its place in natural 
science (see 642 a 31 ff.). It is, however, not the only sort 
of Necessity in Natural science, and not the paramount one. 

* See De gen. et corr. 337 b 25 ff. An example of a non- 
convertible proposition is : Foundations are necessary for a 
house to be built. You cannot say, " If foundations are laid 
a house must of necessity be built," because it is not " ab- 
solutely " and always necessary that a house should be built. 

' Cf. Plato, Philebus 54 a-c. 


or will be in the future." Nor, in a process of 
reasoning of this kind, is it possible to trace 
back the links of Necessity to eternity, so as to say, 
Because A is, therefore Z is. I have, however, dis- 
cussed these matters in another work,^ and I there 
stated where either kind of Necessity applies, which 
propositions involving Necessity are convertible, and 
the reasons why. 

We must also decide whether we are to discuss 
the processes by which each animal comes to be 
formed — which is wliat the earlier philosophers 
studied — or rather the animal as it actually is. 
Obviously there is a considerable difference between 
the two methods. I said earlier that we ought first 
to take the phenomena that are observed in each 
group, and then go on to state their causes. This 
applies just as much to the subject of the process of 
formation : here too we ought surely to begin with 
things as they are actually observed to be when 
completed. Even in building the fact is that the 
particular stages of the process come about because 
the Form of the house is such and such, rather than 
that the house is such and such because the process 
of its formation follows a particular course : the 
process is for the sake of the actual thing, the thing 
is not for the sake of the process." So Empedocles 
was wrong when he said that many of the character- 
istics which animals have are due to some accident 
in the process of their formation, as when he 
accounts for the vertebrae of the backbone by say- 
ing ^ " the fetus gets twisted and so the backbone 
is broken into pieces " : he was unaware (a) that 
the seed which gives rise to the animal must to 
^ Emped. frag. 97 (Diels, Fragmented, 31 b 97). 



640 a ^^ 

€xov SvvajjLLV, €10^ on to TTOLTjoav TTporcpov VTTrjpxcv 
25 ov jjLovov TO) Xoyo) o-AAd /cat rep xpova)' yevva yap 6 
dvdpcjOTTos dvOpcoTTOv, wGTe Sid TO eKelvov rotdvS' 
etvaL T) yiveoLS ToidSe avix^alvei tcoSl. [opioicog 
Se Kal cttI tcov avTop^aTOj? Sokovvtcov yiveodai 
KaOdnep Kal eirl tcx)v Tex^cLOTCov evia ydp^ Kal drro 
TavTopbaTOV ytVerat raura rotS" avro T€)(yr]s, olov 
30 uyteta. a>v^ /xev ovv TrpovTrdpx^t to ttolt^tlkov 
[opLOLov],^ olov Tj'^ dvhpiavT07Toir]TiK'q , OX) [yap]^ yi- 
vcTai avTOfjLaTov. tj Se Texvrj Aoyo? tov epyov 6 
dvev TTJg vXtj? eoTiv. Kal toIs diro Tvxrjs oftotcos" 
COS" ydp T] TexvTj ex^L, ovtcd ytVerat.]*^ Sto /xaAtcrra 
/xev X^KTeov cos" iTretST] tovt^ -^v to dv9pd)Trcp elvai, 
35 hid TOVTO TavT €X€i' OV ydp ivhex^Tai etvai dvev 
TCOV piopLwv TovTCov. €t §6 pLTj, 6 Ti iyyvTaTa 
TOVTOVy Kal ri otl oXcos dSvvaTov aAAco?/ 'q /caAcos" 

640 b ye ovTiog. raura 8' eVerar eVet 8' ecrrt tolovtov, 
TTjv yevecTiv wSl Kal TOiavT'qv GvpL^atveiv dvay- 
KaZov Sto ytVerat TrpdjTov tcqv pLoptcov ToSe, etra 

ToBe. Kal TOVTOV St] tov TpOTTOV OpioicJS €77t TTav- 

^Tcov TCOV <j>vo€i OVV LOT apiiv OJV . 
5 Ot pbkv ovv dpxoloL Kal irpajTOL ^iXoGo^iqcravTes 

^ <Evia yap om. Z^. 

^ <Sv Z : rwv vulg. 

3 om. Zi. 

* 17 Z : om. vulg. 

6 om. Z. 

^ d/Aoicuy (1. 27) . . . yiverai, ex i^/g«. 1032-1034 exorta, 
olim ut vid. in marg. 640 b 4 adscripta ; inepta seclusi. 

' OTt oXcos Z^ : oXojs OTL d. d. vulg. 

" i.e. the same character as the animal which it is to pro- 
duce. For dynamis see Introduction, pp. 30 ff. 
" No doubt a marginal note appended to 640 b 4. 



begin with have the appropriate specific character ° ; 
and (6) that the producing agent was pre-existent : 
it was chronologically earlier as well as logically- 
earlier : in other words, men are begotten by men, 
and therefore the process of the child's formation is 
what it is because its parent was a man. [Similarly 
too -with those that appear to be formed spontane- 
ously, just as with those produced by the arts ; for 
some that are formed spontaneously are identical 
Avdth those produced by art, e.g. health. As for those 
things whose producing agent is pre-existent, e.g. the 
art of statuary, no spontaneous formation occurs. Art 
is the logos of the article wdthout the matter. And 
similarly with the products of chance : they are 
formed by the same process that art would employ.] ^ 
So the best way of putting the matter would be to 
say that because the essence of man is what it is, 
therefore a man has such and such parts, since there 
cannot be a man without them. If we may not say 
this, then the nearest to it must do, viz. that there 
cannot be a man at all otherwise than with them, or, 
that it is well that a man should have them. And 
upon this these considerations follow : Because man is 
such and such, therefore the process of his formation 
must of necessity be such and such and take place 
in such a manner ; which is why first this part is 
formed, then that. And thus similarly with all the 
things that are constructed by Nature. 

Now those who were the first to study Nature in 



640b ^ ^ 

7T€pl (f)VGeoJs Trepl rrjg vXLKrjg apxrjs Kal rrjs roi- 
avTiqs atVias" ioKOTrovv, rt? Kal TToca rt?, /cat ttws 
€K ravTiqs yiverai ro oXov, Kal rivos klvovvtos , olov 
veiKovs r) <j)iXia<^ r) vov rj rod avrofidrov, rrjs 8' 
VTTOKeLjjLevrjs vXr^s roiavhe nva (jiVCiLV ixovorjs i^ 

10 avdyKiqs, olov rod jxev TTvpos Oepfi-^v, rrj? Se yijs 
ipvxpd-v, Kal rod fiev Kovcfi'qv, rrjs Se ^apelav. ovtojs 
yap Kal rov koctjjlov yevvcoaLV. ofjLOLOJs Se Kal irepl 
TTjV T(x)v ^(pcxjv Kal raJv ^urtov yeVeatv XeyovGLV, 
otov^ iv Tip GcofJLaTL peovros p^ev rov vSaros KoiXiav 
y€vio9ai Kal Trdoav vrrohox^jv ttjs re Tpo(f)rJ5 Kal rod 

15 TTepiTTcopiaros, rod he TTvevpLaros hiaTTopevOivro's 
Tovs piVKrrjpag dvappayrjvai. 6 8' drjp Kal to vSojp 
vXrj rcov ocopLarcDv icrriv €k tcov tolovtcov yap 
aoj pbdrcDV ovviurdGi ttjv <j)Voiv Trdvres. el 8' 'ioTLV 
6 dvOpcoTTOs Kal rd t,wa (f)V<jeL Kal rd piopia avrcov, 
X^Kreov dv rrepl oapKos ecrj Kal oarov Kal atfiaTos 

20 Kal TOJV opiOLopLepcbv drrdvrajv, opiOLCOs he Kal rcov 
dvopiOiopiepcov, olov irpooconov, ;)^etpos', ttoSos", fj 
re TOLOVTOV eKaorov eonv avrcov Kal Kard rroiav 
SvvapLLV. ov ydp CKavov ro eV rivcov iorivy olov 
TTvpds ri yrjs, ayoTrep Kav el irepl kXLvtis eXeyopLev rj 
TLVos dXXov rcov roLovrcov, eneLpcopieda pidXXov dv 

25 hiopC^eLV ro elhos avrrjs t) rrjv vX'qv, olov rov ;^aA/<ov 

^ oTi post olov vulg. : del. Ogle. 

" As Empedocles and Anaxagoras, whose attempts to 
discover the " material " and the " efficient " causes are 
mentioned a few lines below. See also Met. 983 b G ff . 

^ " Material " cause : see Introduction, pp. 24 ff. 

* " Residue " : lit. " surplus " ; see Introduction, pp. 32 flF. 

<* Cf. Hippocrates, Uepl 8101x17?, i. 9. 

' " Parts " : see Introduction, pp. 28 ff. 



the early days ° spent their time in trying to discover 
what the material principle or the material Cause ^ 
was, and what it was like ; they tried to find out 
how the Universe is formed out of it ; what set 
the process going (Strife, it might be, or Friendship, 
Mind, or Spontaneity) ; assuming throughout that 
the underlying material had, by necessity, some 
definite nature : e.g. that the nature of Fire was hot, 
and light ; of Earth, cold, and heavy. At any rate, 
that is how they actually explain the formation of 
the world-order. In a like manner they describe the 
formation of animals and plants, saying (e.g.) that the 
stomach and every kind of receptacle for food and for 
residue "^ is formed by the water flowing in the body, 
and the nostril openings are forcibly made by the 
passage of the breath.'* Air and water, of course, 
according to them, are the material of which the body 
is made : they all say that Nature is composed of 
substances of this sort. Yet if man and the animals 
and their parts ^ are products of Nature, then account 
must be taken of flesh, bone, blood, in fact of all the 
" uniform parts," ^ and indeed of the " non-uniform 
parts " too, viz. face, hand, foot ; and it must be 
explained how it comes to pass that each of these is 
characterized as it is, and by what force this is effected. 
It is not enough to state simply the substances out of 
which they are made, as " Out of fire," or " Out of 
earth." If we were describing a bed or any other 
like article, we should endeavour to describe the form 
of it rather than the matter (bronze, or wood) — or, at 

' " Uniform " and " non-uniform " : see Introduction, pp. 
28 ff. The distinction between " uniform " and " non-uniform " 
parts is, historically, the predecessor of the distinction be- 
tween " tissues " and " organs." 



640 b 

Tj TO ^vXov, €L Se jjirj, rrjv ye rod avvoXov kXlvt] yap 

roSe iv rojSe rj roSc roiovSe, ware Kav rrepl rod 
ax'i^P'Ciros €it] XeKreov, /cat ttolov rr]v ISeav tj yap 
Kara ttjv i.Lop(f)r)v ^vgis KvpLOjrepa rfj? vXiKrjs 
30 Et fiev ovv Tw G'xriixaTL Kal rco ;^pc6^aTt eKaarov 
ioTL Tcx)v re t,a)a)V Kal tojv iiopiojVy opdcjs av 
ArjjjLOKpLTOS XeyoL' ^atVerat yap ovtojs VTToXa^elv. 
(jyricrl yovv rravrl St^Aov elvai olov n ttjv pLopcfy-qv 
iariv 6 dvOpcxJTTOS, ojs gvtos avrov rw re cr;^-)]/^aTt 
Kal Ta> ■)(pd)\xaTi yvcxipiyiov. Kairoi Kal 6 redvews 

35 €X€L TTjV aVTTjV TOV GX^jp^CLTOS p.Opcji'^V, (lAA* OjLtOJS' 

ovK ecTTLV avdpojTTOS' €TL 8* dSvvarov etvat X^^P^ 
OTTOJGOVV hiaK€ipi€vr]v , olov x^^Xktjv t) ^vXivriVy ttXtju 

641 a opLOJVvpiOJS, a)07T€p TOV yeypapLpLEvov larpov. ov yap 

hwrjoeTai TTOieiv ro iavrrjs epyoVy a)GTTep ouS' aj5Aot 
XlOlvol to iavTcov epyov, ouS' o yeypapipiivos laTpog. 
opLOiwS Se TOVTOLs ovhe rcDv tov TeOvrjKOTOS fJLO- 
6 piiov ovhev ert twv tolovtojv eGTL, Xeyoj 8* olov 
6(j)daXp6si X^^P' Xlav ovv clttXcos etp'qTaL, Kal tov 
avTOV TpoTTOv wGTTep dv el T6KTOJV XeyoL TTepl x^^pos 
^vXivqs. ovTCx)s ydp Kal ol <f)VGLoX6yoi Tas yeviGeis 
Kal ras" air las tov GX'ripaTos XeyovGiv. vtto tlvojv 
ydp iSrjpLOvpyrjOrjGav hvvdpieojv ; dXX lgcjds 6 p,ev 
10 tcktcuv ip€L TTeXeKvv ^ Tpvnavov, 6 8' aepa Kal yrjVf 

" See Diels, Fragmented, 68 b 165. 
" i.e. the early writers on " Nature.'* 



any rate, the matter, if described, would be described 
as belonging to the concrete whole. For example, 
" a bed " is a certain form in certain matter, or, 
alternatively, certain matter that has a certain form ; 
so we should have to include its shape and the manner 
of its form in our description of it — because the 
" formal " nature is of more fundamental importance 
than the " material " nature. 

If, then, each animal and each of its parts is what it 
is in virtue of its shape and its colour, what Demo- 
critus says will be correct, since that was apparently 
his view, if one understands him aright when he says 
that it is evident to everyone what " man" is like as 
touching his shape, for it is by his shape and his 
colour that a man may be told." Now a corpse has 
the same shape and fashion as a living body ; and 
yet it is not a man. Again, a hand constituted in 
any and every manner, e.g., a bronze or wooden 
one, is not a hand except in name ; and the same 
applies to a physician depicted on canvas, or a flute 
carved in stone. None of these can perform the 
functions appropriate to the things that bear those 
names. Likewise, the eye or the hand (or any other 
part) of a corpse is not really an eye or a hand. 
Democritus's statement, therefore, needs to be quali- 
fied, or a carpenter might as well claim that a hand 
made of wood really was a hand. The physiologers,^ 
however, when they describe the formation and the 
causes of the shape of animal bodies, talk in this 
selfsame vein. Suppose we ask the carver " By what 
agency was this hand fashioned ? " Perhaps his 
answer will be " By my axe " or " By my auger," 
just as if we ask the physiologer " By what agency 
was this body fasiiioned ? " he will say " By air " and 

c2 67, 


641a ^ ^ 

rrX-qv ^eXriov 6 reKTcov ov yap iKavov ear at aura) 

TO TOOovTov enrelv, on ejjLTTeaovTos rod opydvov 

TO fJLev KolXov iyevero to 8e eVtVeSov, dAAa Sloti, 

Tr)v nXriyy^v enoirjoaTO ToiavTTjv, koI tlvos eVe/ca, 

epet Trjv alriav, ottws Toiovhe r] Toiovhe ttote ttjv 

ixopi^rfv yevrjTai. 

15 A^AoV TOLVVV OTL OVK OpOcbs XdyOVdi, Kal OTL 

XeKTeov CO? tolovtov to ^cvov, Kal nepl eKeivov Kal 

tL Kal TTOLOV Tt Kal TCJbv fJLOpLOJV eKaUTOV ,^ a)G7T€p 

Kal TTepl Tov etSovs Trjg kXlvt]?. 

Et St] tovto idTL i/j^xV V ^^XV^ p^^pos t) pLT] dvev 
^vx^js {aTreXdovGT]? yovv ovkIti ^coov icTTiv, ovSe 
20 Tcov pLopiojv ovhkv TO avTO AetVerat, ttXt^v to! 
ax^Jp-CLTL p,6vov, KaOoLTTep TO, pLvdevojJLeva XidovoOai), 
el St] TavTa ovtojs, tov (J)vglkov irepl ^vx'^S OiV etrj 
Xeyeiv Kal elhivai, Kal et /xt) Trdar]?, /car' auro 
tovto Kad^ O TOLOVTO TO ^cpov, Kal Tt eoTiv Tj ipvxT]» 

7j avTO TOVTO TO pLopiov, Kal TTepl Tojv GvpL^e^y]- 

25 KOTCJV KaTa Tr]v TOiavTTjv avTTJs ovaiaVy d'AAcos" re 

Kal TTJs (f)vaeojs Slxco? Xeyop.evr]s Kal ovGr]s, ttjs 

pLev CVS vXrjs, ttjs S' cos" ovGias' Kal eoTiv avTi) Kal 


^ €KdaTov Peck : eKaarov vulg. 

* Or, " reason " ; see Introduction, p. 24. 

*> See above, 640 b 26. 

• " Soul " : see Introduction, pp. 34 ff, 

* Or " motive." 



" By earth." But of the two the craftsman will give 
a better answer, because he will not feel it is sufficient 
to say merely that a cavity was created here, or a 
level surface there, by a blow from his tool. He will 
state the cause'^ on account of which, and the purpose 
for the sake of which, he made the strokes he did ; 
and that will be, in order that the wood might finally 
be formed into this or that shape. 

It must now^ be evident that the statements of the 
physiologers are unsatisfactory. We have to state 
how the animal is characterized, i.e., what is the 
essence and character of the animal itself, as well as 
describing each of its parts ; just as with the bed we 
have to state its Form.^ 

Now it may be that the Form of any living creature 
is Soul,^ or some part of Soul, or something that in- 
volves Soul. At any rate, when its Soul is gone, it 
is no longer a living creature, and none of its parts 
remains the same, except only in shape, just like the 
animals in the story that were turned into stone. 
If, then, this is really so, it is the business of the 
student of Natural science to inform himself con- 
cerning Soul, and to treat of it in his exposition ; 
not, perhaps, in its entirety, but of that special part 
of it which causes the living creature to be such as it 
is. He must say what Soul, or that special part of 
Soul, is ; and when he has said what its essence is, 
he must treat of the attributes which are attached 
to an essence of that character. This is especially 
necessary, because the term " nature " is used — 
rightly — in two senses : (a) meaning " matter," and 
(6) meaning " essence " (the latter including both 
the "Efficient"^ Cause and the "End"). It is, of 
course, in this latter sense that the entire Soul or 



641 a ^ 

rjroL Trdaa rj i/jvxr) 'q fiepo? n avrrj?. ojare /cat 
ovTios av XeKTeov e'lrj rco nepl ^uctcco? OeojprjTLKCp 

30 7T€pi ^VXrjS lldWoV 7) 7T€pl TTj? vXt}? , OGCp floiXXoV T) 
vXr] St' iK€LV7]V (j)VOlS €GTLV T} dvcLTTaAtv /Cat yoLp 

kXlvtj /cat rpiTTOVs to ^vXov eariv, ort Sura/xet ravra 

^ATrop-qG€i€ 8' dv rt? els to vvv XexOev eVtjSAei/ras', 

TTorepov 7T€pl TTOLGTjs ^VX'^^ '^V^ cfyvGLKrjg iuTL TO 

35 etTTetv rj Trepi rivos} et yap rrepl TTOLGrjs, ovhepiia 

AetVerat Trapa ttjv (l)V<JLKrjv iTTLaTT^pLrjv <j)LXoGO(j)ia. 

641 b o yap vovs rcbv vorjrcoVy coo-re Trepl ttolvtcjov t) 

(f)VGiKrj yvwGLS av eir]' rrjs yap avrrjg Trepl vov /cat 

rod vofjTov OecxjpijGaL, eiTrep Trpog aXXr^Xa, Kai tj 

avrr] dewpla rcJov rrpos dXXiqXa TravTOJi', KaOaTrep 

/cat rrepl aiGd-qGeajs /cat rojv alGBr]ra)V. 7) ovk 6GTL 

5 TT-aaa rj ^wx^} KLvrJGecos dpx'^> ovSk rd piopia diravra, 

dXX av^rjaeajg [xev onep /cat iv roZs (jyvrols, aA- 

Aotojo'ews' Se TO aLGOrjTLKov, (f)opd£ 8' erepov n /cat 

ov TO voTjTLKov vTrdpxei ydp Tj (f)Gpd /cat iv erepoLS 

rojv ^cpa)Vy SidvoLa 8' ouScri. SijXov ovv w? ov 

^ Tiios {^lopiov) Rackham. 

" i.e. qualitative change, which is the " motion " proper 
to this part of the Soul. 



some part of it is the " nature " of a living creature. 
Hence on this score especially it should be the duty 
of the student of Natural science to deal with Soul 
in preference to matter, inasmuch as it is the Soul 
that enables the matter to "be the nature " of an 
animal (that is, potefitialli/, in the same way as a piece 
of wood " is " a bed or a stool) rather than the matter 
which enables the Soul to do so. 

In view of what we have just said, one may well ask 
whether it is the business of Natural science to treat 
of Soul in its entirety or of some part of it only ; 
since if it must treat of Soul in its entirety (i.e. 
including intellect) there will be no room left 
for any other study beside Natural science — it ^vill 
include even the objects that the intellect appre- 
hends. For consider : wherever there is a pair 
of interrelated things, such as sensation and the 
objects of sensation, it is the business of one 
science, and one only, to study them both. Now 
intellect and the objects of the intellect are 
such a pair ; hence, the same science will study 
both of them, which means that there will be 
nothing whatever left outside the purview of 
Natural science. All the same, it may be that 
it is neither Soul in its entirety that is the 
source of motion, nor yet all its parts taken 
together ; it may be that one part of Soul, (a), viz. 
that which plants have, is the source of growth ; 
another part, (6), the " sensory " part, is the source 
of change"; and yet another part, (c), the source 
of locomotion. That even this last cannot be the 
intellectual part is proved, because animals other 
than man have the power of locomotion, although 
none of them has intellect. I take it, then, as evident 



641b ^ ^ , , r X ^ X 

Trepl Trdu-qs ^vx^j? XeKreov ovhk yap Trdaa ^vx^] 

10 (f>V(n£, dXXd Tt {jLopLov avrrjg ev t) Kal rrXeioj. 

"Ktl Se TcDv €^ dcf)aLp€G€OJs ovSevos olov r etvat 
rrjv (jyvaiKrjv OecoprjriKriv, iTTetSrj rj (f)VGis eVe/ca rov 
TTOtet TTOLvra' ^atVerat yap, wanep ev rols re^ya- 
oroZs eorlv rj re-xyri, ovrojs ev avrols roZs Trpay- 
fxaGLV dXXr] ns dpxrj Kal air La roLavrr], tjv exofiev 

16 Kaddirep to Oeppiov Kal to ijjvxpov €K tov rravTos. 
8t6 pidXXov eLKos TOV ovpavov yeyevrjadai vtto 
roLavTTjs atrta?, el yeyove, Kal etvai Sid TOuavTrjv 
aiTLav [jLaXXov rj to. ^oja Td dvrjTd' to yovv rcray- 
piivov Kal TO djpLGjjievov ttoXv fxdXXov <^aiveTai ev 

20 Tols ovpavLOLS 7j TTcpl 7]jU,as", TO S* dXXoT* aAAcu? Kat 
CO? eTvx^ nepl Td dvrjTa fidXXov. ol Se rcov fxev 
^cpojv eKaoTov (f)VG€L (j)aGlv etvai Kal yeveGdau, tov 
8' ovpavov aTTo tvx'^s Kal tov avTOfidTOV tolovtov 
GVGTTJvai, ev (h aTTO Tvx''^S Kal ara^ta? oi58' otlovv 
^atVerat. iravTaxov he Xeyo[iev ToSe tovS* eVc/ca, 

25 07T0V dv (jyaivrjTai reAo? Tt npo^ o rj KivrjGis rrepaivei 
pi/rjhevds ejXTTohit^ovTOs. cocrre etvai (jyavepdv oti ccrrt 
Tt TOLOVTOV, o Srj Kal KaXovjiev (f)VGLV' ov ydp Srj 
6 Tt eTVX^v e^ eKdGTOV yiveTai GirepjiaTOs, dXXd 
ToSe €/c Tovhey ovhe Girepfia to tvxov e/c tov tv- 

« With this passage cf. Plato, Phihhus 29-30. 
" Cf. Samuel Butler, Life and llahit, p. 134, " A hen is 
only an egg's way of making another €:g^.'' 



that we need not concern ourselves with Soul in its 
entirety ; because it is not Soul in its entirety that is 
an animal's " nature," but some part or parts of it. 

Further, no abstraction can be studied by Natural 
science, because whatever Nature makes she makes 
to serve some purpose ; for it is evident that, even 
as art is present in the objects produced by art, so in 
things themselves there is some principle or cause of 
a like sort, which came to us from the universe around 
us, just as our material constituents (the hot, the 
cold, etc.) did.'^ Wherefore there is better reason for 
holding that the Heaven was brought into being by 
some such cause — if we may assume that it came 
into being at all — and that through that cause it 
continues to be, than for holding the same about the 
mortal things it contains — the animals ; at any rate, 
there is much clearer evidence of definite ordering 
in the heavenly bodies than there is in us ; for what 
is mortal bears the marks of change and chance. 
Nevertheless, there are those who affirm that, while 
every living creature has been brought into being 
by Nature and remains in being thereby, the heaven 
in all its glory was constructed by mere chance 
and came to be spontaneously, although there is no 
evidence of chance or disorder in it. And whenever 
there is evidently an End towards which a motion 
goes forward unless something stands in its way, then 
we always assert that the motion has the End for its 
purpose. From this it is evident that something of 
the kind really exists — that, in fact, which we call 
" Nature," because in fact we do not find any chance 
creature being formed from a particular seed, but A 
comes from a, and B from b ; nor does any chance 
seed come from any chance individual.^ Therefore 


641 b ^ 

x6^TO£ GcofMaTOs. o.px^ oipoL Kal TTOiriTiKov rod ef 
30 avTOV TO (l^ ov t6)^ GTrepfia. (jivuei yap ravra' 
(f)V€Tai, yovv €K tovtov. dAAa fjurjv 'in rovrov 
TTporepov ro ov to oirlpixa' yeveois jnev yap to 
onepfxa, ovoca Se to reXos. dfX(f)OLV 8* en irpo- 
T€pov, dcf)* ov iorl to CTrep/xa. eom yap to 
OTripixa St;^a>s', e^ ov t€ Kal ov- Kal yap dcf)* od 
35 aTTrjXOe, tovtov OTreppia, olov lttttov, Kal tovtov 
o euTat i^ avTov, otov opecos, Tpoirov 8* ov tov 
avTOVy aXX eKaTepov tov elprjfievov. eVt 8e SvvdfJLei 

642 a TO GTrepfxa' hvvapus 8' co? e;^et irpos ivTeXdx^f-OLV 


Etotv dpa 8u' atTtat avTai, to 6^ ov ev€Ka Kal 
TO cf dvdyKTjs' TToXXd yap yiveTai, otl dvayK-q. 
LGOJS 8' dv TL5 dTropr]G€Le TToiav XeyovGiv dvdyK-qv 
6 ol XiyovTe? i^ dvdyKrjs- tcov [xev yap Svo TpoTTOiv 
ovSeTepov otov 9^ vrrdpx^iv tcov SiajpLGfievcov ev toI? 
Kara ^iXoGo^iav. €gtl 8' ev ye toIs exovgl yeveoLV 
7) rpLTT]' Xeyofxev yap Tr]v Tpo(j)r]v dvayKalov tl KaT 
ovheTepov tovtojv tcov Tponajv, dAA' otl ovx olov t 
dvev TavTrjs elvai. tovto S' ioTLV ojOTrep e^ vtto- 
10 Oiaecjs' woTTep yap irrel 8et cp^t^etv tco TreXeKet, 
dvayKT] GKXrjpov etvai, el he GKXrjpov, ;)(aA/<ouv ^ 

^ <i$ ov ro> supplevi, 2 secutus. 

«» There is a reference here, which is not apparent in the 
English version, to the etymological connexion between ^uats 
(nature) and 4>v€odai (to grow). Cf. Met. 1014 b 16 ff. 

^ Viz. actuality is prior to potentiality. 

* These treatises are referred to again in the Politics 
(1282 b 19) and in the Eudemian Ethics (1217 b 23). The 
two modes of necessity seem to be (1) " absolute " necessity 
(mentioned here), and (2) " coercive " necessity (see Met, 


the individual from which the seed comes is the 
source and the efficient agent of that wliich comes 
out of the seed. The reason is, that these things 
are so arranged by Nature ; at any rate, the offspring 
grorvs ° out of the seed. Nevertheless, logically 
prior to the seed stands that of M'hich it is the seed, 
because the End is an actual thing, and the seed is 
but a formative process. But further, prior to both 
of them stands the creature out of which the seed 
comes. (Note that a seed is the seed " of " some- 
thing in two senses — two quite distinct senses : it 
is the seed " of" that out of which it came — e.g. a 
horse — as well as " of " that which will arise out of 
itself — e.g. a mule). Again, the seed is something 
62/ potentiality, and we know what is the relation of 
potentiality to actuality.^ 

We have, then, these two causes before us, to wit, 
the " Final " cause, and also Necessity, for many 
things come into being owing to Necessity. Per- 
haps one might ask which " Necessity " is meant 
when it is specified as a cause, since here it can be 
neither of the two modes which are defined in 
the treatises WTitten in the philosophical manner.*' 
There is, however, a third mode of Necessity : it 
is seen in the things that pass through a process of 
formation ; as when we say that nourishment is 
necessary, we mean " necessary " in neither of 
the former two modes, but we mean that without 
nourishment no animal can be. This is, practically, 
"conditional" Necessity. Take an illustration: A 
hatchet, in order to split wood, must, of necessity, be 
hard ; if so, then it must, of necessity, be made of 

1015 a 20 ff.). The third he has referred to already at 
639 b 2o. viz. " conditional " necessity. See pp. 21 f. 



642 a 

aiSrjpovv, ovTCxj /cat eVet to aajjjLa opyavov {eveKa 

Tivos yap eKaorov tojv p,opLCOv, opLoica^ he kol to 
oXov), dvdyKrj dpa tolovSl etvau /cat €/c rotcovSt, el 
CKelvo ecrrat. 
"Otl ixev ovv hvo Tpoiroi ttjs atrtas", /cat Set 

15 Aeyovras" Tvyxdveiv fidXioTa fjL€V dpL^olv, et 8e jLtTy, 
TTeipaadai ye TTOieZv tovto, SijXov,^ /cat ort TrdvTeg ol 
TOVTO fjLT] XeyovTes ovSev ws etVetv Trepl <f)VGeoJS 
Xeyovoiv dpx^) ydp tj (j)VGis /xaAAov ttjs vXtjs. 
{ivLaxov Se rrov avTTJ /cat 'E/XTreSo/cAT^s" TreptTrtTrret, 
dyo/Jievos vtt^ avTrjs ttjs dXr^deias, /cat tt^v ovoiav /cat 

20 TrfV (f)vaLV aray/ca^erat (jydvai tov Xoyov elvai, olov 
ooTovv dTroStSous" tL eoTiv ovTe ydp ev rt rcoi/ 
aTOix^icQv Xeyet auro oure 8uo ■^ r/Jta oyVe TrdvTa, 
dXXd Xoyov TTJs /xt^ecos" avTcov. SrjXov tolvvv ort 
Kat T] odp^ TOV avTov Tporrov eoTi, /cat tcov dXXcov 


25 eXdelv Tovs irpoyeveoTepovs CTrt tov Tpoirov tovtov, 
OTL TO Tt rjv elvai /cat to opioaodai ttjv ovoiav ovk 
rjvy dXX rjipaTO fiev ArjpLOKpLTOs 7Tpa>TO?, cos* ovk 
dvayKaiov Se ttj (j)vaLKfj Becjopia, dXX eK(f)ep6pievos 
vrr* avTov tov TTpdyfiaTos' eirl HojKpdTovs he tovto 
liev r]v^-q9r), to he ^rjTetv to, Trepl (j)Voecx)s ^Xrj^e, 
^ sic Ogle : el 8e fi-q, BrjXov ye TreipdaOai, ttouZv vulg. 

« See Diels, Fragmented, 31 a 78. 

* " Element " : this term is normally used to denote the 
four substances, earth, water, air, fire. 

" This is probably a reference to Democritus's opposition 
to the theories of Protagoras, who held that " what appears 


bronze or of iron. Now the body, like the hatchet, 
is an instrument ; as well the whole body as each 
of its parts has a purpose, for the sake of which it 
is ; the body must therefore, of necessity, be such 
and such, and made of such and such materials, 
if that purpose is to be realized. 

It is, therefore, evident that of Causation there are 
two modes ; and that in our treatise both of them 
must be described, or at least an attempt must be 
made to describe them ; and that those who fail 
herein tell us practically nothing of any value about 
" Nature," for a thing's " nature " is much more a 
first principle (or " Cause ") than it is matter. (In- 
deed, in some places even Empedocles, being led 
and guided by Truth herself, stumbles upon this, 
and is forced to assert that it is the logos which is a 
thing's essence or nature." For instance, when he is 
explaining what Bone is, he says not that it is any one 
of the Elements,^ or any two, or three, or even all of 
them, but that it is " the logos of the mixture " of 
the Elements. And it is clear that he would explain 
in the same way what Flesh and each of such parts is. 
Now the reason why earlier thinkers did not arrive 
at this method of procedure was that in their time 
there was no notion of ** essence " and no way of 
defining " being." The first to touch upon it was 
Democritus ; and he did so, not because he thought 
it necessary for the study of Nature, but because he 
was carried away by the subject in hand and could 
not avoid it." In Socrates' time an advance was 
made so far as the method was concerned ; but at 
that time philosophers gave up the study of Nature 

to he to you, is for you." Protagoras had emphasized the 
validity of sense-data ; Democritus denied it. 



642a ^ ^ ^ 

30 TTpos he rrjv xPV^i-H-ov dperrjv Kal rr]v ttoXltlktjv 

OLTTeKXiVaV ol (f)LXoGO(f)OVVT€£ .) 

AeiKTeov 8* ovrojs, olov on eari ixev rj dvaTTVorj 

TOvSl x^P^^y 'TOVTO 8e ytVcTat 8ta raSe ef dvdyKrjs, 

7j 8* dvdyKTi ore /xev orjfjLalveL on el eKeZvo eorai 

TO ov eveKa, ravra dvdyKT] eorlv {ourcos')^ ^X^^^> 

35 ore 8' on eonv ovroj? e^ovra Kal Tre^u/cora* to 

depfJLov yap dvayKaZov efteVat /cat irdXiv elaievai 

dvTLKpovov, Tov 8' dipa elapetv tovto S* 17817 

642 b dvayKalov ionv, rod ivros 8e Oepfiov dvnKOTrrovros 

iv rrj ipv^eL rov OvpaOev depos rj etooSos^ /cat 17 

6^080?. o fjLev ovv rporros ovrog 6 rrjs ixeOoSov, 

/cat rrepl (Lv hel Xa^elu rds alrlas, ravra /cat 

rotavrd eonv. 

5 II. AafjL^dvovorL 8* eVtot to /ca^' eKaarov, 8t- 

atpovfjievoL ro yevos els hvo hia(j}opds. rovro 8' eoTt 

rfj piev ov pdSiov, rfj he dhvvarov. ivlojv yap eorai 

^ ovTcos supplevi. 
* 17 eiGoSos om. pr. E. 

" " Goodness," or " virtue," is one of the chief topics 
discussed by Socrates in the Platonic dialogues. Cf. 
Aristotle, Met. 987 b 1, " Socrates busied himself about moral 
matters, but did not concern himself at all with Nature as 
a whole." 

'' I have not attempted, except by one insertion, to straigh- 
ten out the text of this confused account, which looks 
like a displaced note intended for the paragraph above 
(ending " realized," p. 77). If it is to remain in the text, it 
would follow at that place (after 642 a 13) least awkwardly. 
For a more lucid account of the process of Respiration see 
De resp. 480 a 16-b 5. 

* This is usually held to include Plato, on the ground that 


and turned to the practical subject of " goodness," ** 
and to political science.) 

^ Here is an example of the method of exposition. 
We point out that although Respiration takes place 
for such and such a purpose, any one stage of the 
process follows upon the others hy necessity. Neces- 
sity means sometimes {a) that if this or that is to 
be the final Cause and purpose, then such and such 
things must be so ; but sometimes it means (6) that 
things are as they are owing to their very nature, as 
the following shows : It is necessary that the hot 
substance should go out and come in again as it 
offers resistance, and that the air should flow in — 
that is obviously necessary. And the hot substance 
within, as the cooling is produced, offers resistance, 
and this brings about the entrance of the air from 
\vithout and also its exit. This example shows how 
the method works and also illustrates the sort of 
things whose causes we have to discover. 

II. Now some ^^Titers ^ endeavour to arrive at the 
ultimate and particular species by the process of 
dividing the group (genus) into two differentiae.^ 
This is a method which is in some respects difficult 
and in other respects impossible. For example : 

the method of dichotomy is used in the Sophist and Politicus. 
But the method can hardly be said to be seriously applied 
to the classification of animals in the Politicus, and in the 
Sophist it is introduced partly in a humorous way, partly 
to lead up to the explanation of to /xt) ov (not-being). Either 
Aristotle has mistaken the purpose of the method (as he 
has at An. Pr. 46 a 31 if.) or (much more probably) he is 
referring to some other writer's detailed application of it. 
See e.g. Stenzel in Pauly-Wissowa, s.v. Speusippus. 

^ Each stage of the division gives two differentiae, which 
are treated as " genera " for the next stage of the division, 
and so on. 



642 b 

8ia(f)opa fJLia ixovq, to, 8' ctAAa rrepUpya, olov vtto- 

7TOVV, hirrovv, gxI'^ottovv^' avrrj yap fMOvrj Kvpia. 

10 et he pLT], ravTov TroWaKis avayKolov XeyeLV. en 
Se TTpoGT^Kei {jLTj hiaoTTav eKaoTOv yevos, olov rovs 
opvidas rovs fxev iv rfjSe rovs 8* eV dXXr) Statpeaet, 
Kaddnep ep^oucrtv at yeypafifidvaL hiaLpiaeis' e/cet 
yap rovs fJiev pLera rajv ivvSpojv cru/x^atVet 8t- 
Uprjadai, rovs 8' iv dXXo) yevei. (ravrj] fxev ovv rfj 

15 opLOLorrjri opvis ovofia KeZr at, irepa 8' IxOvs' aAAat 
8* elalv dvwvvpiOL, olov ro evaifxov /cat ro dvaipLOV' 
icf)^ eKarepo) yap rovrcov ov Kelrai iv ovofxa.) etnep 
OVV /XT^Sev ra>v ojJLoyevojv hiauTraorioVy rj els hvo 
hiaipeuis pidraios dv etr]- ovrco yap hiaipovvras 
avayKatov ;^6opt^etv Kal hiaorrdv rdjv ttoXvttoSojv 
yap ion rd jjiev iv rols Tre^ols rd 8* iv rols 

20 ivvSpois. 

III. "Ert orep-qoei /xev dvayKaZov 8tatpetv Kal 
hiaipovGiv ol Sixorofiovvres. ovk eon 8e hia^opd 

^ arrow post oxiI,6itovv vulg., del. Ogle ; fortasse [a-nTepov] 
scribendum (cf. An. Post. 92 a 1, Met. 1037 b 34). 

<* Other groups will get broken up under several lines of 
division, as Aristotle goes on to say, and he repeats this at 
643 b 14, where he adds that " contrary " groups will get 
lumped together under a single line (and " contrariety is 
maximum ' difference,' " see Met. 1055 a 5 ff., cf. 1018 a 30). 

" Aristotle holds that one is not enough ; see 643 b 9 ff. 
and 29 ff. 


PARTS OF ANIMALS, I. ii.-iii. 

(a) Some '^ groups will get only one differ ejilia,^ the 
rest of the terms being superfluous extras,'' as in the 
example : footed, two-footed, cloven-footed ^ — since 
this last one is the only independently valid differentia. 
Otherwise the same thing * must of necessity be 
repeated many times over. 

(b) Again, it is a mistake to break up a group, as 
for instance the group Birds, by putting some birds 
in one division and some in another, as has been done 
in the divisions made by certain wTiters : in these 
some birds are put in with the water-creatures, and 
others in another class. (These tw^o groups, each 
possessing its own set of characteristics, happen to 
have regular names — Birds, Fishes — but there are 
other groups which have not, e.g. the " blooded " 
and " bloodless " groups : there is no one regular 
name for either of these.) If, then, it is a mistake 
to break up any group of kindred creatures, the 
method of division into two will be pointless, because 
those who so divide are compelled to separate them 
and break them up, some of the many-footed animals 
being among the land-animals and others among the 

III. (c) Again, this method of twofold division 
makes it necessary to introduce privative terms, and 
those who adopt it actually do this. But a privation, as 

" i.e. all terms except the final one can be dispensed with, 
because none of them constitutes an independent (/cupta) 
differentia ; one line of division yields one valid differentia 
and no more (c/. 644 a 2-10). 

<* Cf. 644 a 5 and Met. 1038 a 32. 

• In this case, " -footed " {cf. Met. 1038 a 19 if.).^^ But 
Aristotle does not explain how Si'tt-ouv is " superfluous." 



642 b 

orep'^uecog fj oTipiqcjiS' ahvvarov yap eih-q ^Ivai rou 

fiT] ovTos, OLOV T^s" aTToSta? t) tov arrripov cocTTTcp 
TTTepojaecxis kol ttoSwv Set Se rrjg KaOoXov 8ta- 

25 <f)opdg etSr] etvai' el yap {jltj ecrrat, 8ta rt av eiy] 
Tcov KaOoXov Kal ov rcJov KaB^ eKaorov ; rcov he 
hiacfyopujv at ju-ev KaOoXov elal Kal e-xpvaiv etSr], 
OLOV TTTeporrjs' to [JLev yap aox^JTOv ro S' ^^X''~ 
GfJievov iarl Trrepov. Kal ttoSottj^ (haavTCOS r] [lev 
TToXvGX^hTjs, 7] he hiox^hiqs i OLOV ra hlxoiXa, tj 8* 

30 oLGXi-hrjg Kal dhLalperos, olov ra fXwvvxO" ;\;aAc7rov 
fxev ovv hiaXa^eLV Kal elg roiavras hiacfyopas cSv 
euTLV ethT], wgO^ otlovv ^cpov ev ravrai? v'rrdpx€iv 
Kal {jLTj ev TrXeioGL ravrov [olov TTrepojTov Kal 
drrrepov eoTL yap dficfico ravrov, otov [xvpfjir]^ Kal 

35 XafjLTTVpls Kal erepd rLva), irdvrojv he x(^Xe7Twrarov 
•^ dhvvarov els rds dvrLKeLfxevag } dvayKalov yap 
rcov Kad^ eKaorov vTrdpx^LV rLvl rwv hLa(f)opd)v 

643 a eKd(7r7]Vy ware Kal rrjv dvriKeLixevrjv . el he (jlt] 

evhex^TO^L rols etheL hiacfyepovoLV inrdpx^tv ethos rL 
rrjs ovaias drofjiov Kal ev, dAA' aet hLacfiopdv e^eL 
^(oLOv opvLS dvOpojTTOV — T) 8t77oSia ydp dXXr) Kal 
8ta</)opo?* Kav el eVat/xa, ro af/j-a hid(f)opov, rj ovhev 
6 TT^S" ovalas ro alfia dereov) — el 8' ovrojs eurLV, 7] 

^ ras dvTiK€Lix€vas Peck : ret avriK^iiia>a Titze : ra dvaifia 
vulg. : Ttt ivavria Ogle : to. drofxa Prantl. 
2 11. 3-6 interpunctionem correxi. 

" I have not attempted to keep a consistent translation for 
mepoi; as Aristotle applies this term to " feathers " and to 
" wings " (of insects). 


privation, can admit no differentiation ; there cannot 
be species of what is not there at all, e.g. of " foot- 
less " or " featherless," ^ as there can be of " footed " 
and " feathered " ; and a generic differentia must 
contain species, else it is specific not generic. How- 
ever, some of the differentiae are truly generic and 
contain species, for instance " feathered " (some 
feathers are barbed, some unbarbed) ; and likewise 
" footed " (some feet are " many-cloven," some 
" twy-cloven," as in the animals with bifid hoofs, 
and some '* uncloven " or " undi\ided," as in the 
animals with solid hoofs). Now it is difficult enough 
to arrange the various animals under such hnes of 
diflPerentiation as these, which after all do contain 
species, in such a way that every animal is included in 
them, but not the same animal in more than one of 
them (e.g. when an animal is both Avinged and wing- 
less, as ants, glow-worms, and some other creatures 
are) ; but it is excessively difficult and in fact im- 
possible to arrange them under the opposite lines of 
differentiation. Every differentia must, of course, be- 
long to some species ; and this statement wall apply 
to the negative differentiae as well as to the positive. 
Now it is impossible for any essential characteristic 
to belong to animals that are specifically different and 
at the same time to be itself one and indivisible ^ : it 
^'V'ill always admit of differentiation. (For example, 
Man and Bird are both two-footed, but this essential 
characteristic is not the same in both : it is differenti- 
ated.^ And if they are both " blooded," the blood 
must be different, or else it cannot be reckoned as 
part of their essence.) If that is so, then, the one 

* As the privative characteristic would have to be. 
« See below, 693 b 2 ff . 



643 a ^ 

Ilia hia(f)Opa hvcrlv vrrdp^ei-^ et 8e rovro, SrjXov 
on dSvvarov Greprjoiv elvai hia^opdv. 

"Ecrovrat 8' at hia(j>opal laai roZs dropiOLs t,(LoiSt 
elirep dropid re ravra /cat at Sta^opat dropLOL, 
KOLV7] Se jLtT^ ioTLV. (ft 8' ivSex^Tai VTrdpx^t'V^ Kal 

10 Koivrjv, dropLOV Se, SrjXov on Kard ye ri^v Koivrjv eV 
to) auToJ ionv erepa oVra toj et8et ^oia. coctt' 
dvayKoloVy el tSiot at hiacfiopal els a? dnavra 
€pL7TL7TT€i TO, dropLa, pLiqSejjLLav avTcov etvat KOivqv 
el 8e jLtrJ, erepa dvra els to^v avrrjv jSaStetrat.) 8£t 
8' OL»Te TO auTO /cat dropLOV els erepav /cat erepav 

lb levai Stacjiopdv rcov Sirjpr]pievojv, ovr els rrjv avrrjv 
erepa, /cat diravra els ravras. (f)avep6v roivvv on 
ovK ean Xa^elv rd dropua eiSr] (Ls SiaLpovvrat at els 
Svo hiaipovvres rd t^cpa rj /cat d'AAo onovv yevos. 
/cat yap /car' eKeivovs dvayKalov laas rds eo^dras 
elvai Siacfyopds rols ^(-pois TrduL rots dropLOLS ro) 

20 etSet. ovros yap rovhe nvos yevovs, ov Sta(^opat 
rrpoirai rd (XevKd /cat rd p^yiY XevKd, rovrojv 8' 
eKarepov aAAat, /cat ovra>s els rd Trpoao) ecus rojv 
dropicov, at reXevralai rerrapes eaovrai r) a'AAo n 

^ 11. 3-6 interpunctionem correxi. 

^ /A17 vTrapx^Lv vulg. : corr. Titze, 

^ supplevit Cornford. 

•* Because it cannot fulfil the condition of admitting 
differentiation. At whatever stage of the division it comes 
(unless at the very end), the privative term will cover at least 
two species, and therefore at the next stage the dichotomists 
will have to divide it — illegitimately, as Aristotle maintains. 


differentia will belong to two species. And if so, 
it is clear that a privative cannot be a valid 

(d) Now assuming that each species is indivisible : if 
each differentia also is indivisible, and none is common 
to more species than one, then the number of differ- 
efitiae will be equal to the number of species. (Suppos- 
ing it were possible to have a differentia which though 
indivisible was common ; clearly, in that case, animals 
which differed in species would be in the same division 
in virtue of that common differentia. Therefore, if the 
differentiae under which the indivisible and ultimate 
species fall are to be proper and private to each 
one, it is necessary that no differentia be common ; 
otherwise, species which are actually different will 
come under one and the selfsame differentia.^ And 
we may not place one and the same indivisible 
species under two or three of the lines of differentia- 
tion given by the divisions ; nor may we include 
different species under one and the same line of 
differentiation. Yet each species must be placed 
under the lines of differentiation available. It is 
evident from this that it is impossible to arrive at the 
indivisible species either of animals or of any other 
group by the method of twofold division as these 
people practise it, for even on their showing the 
number of ultimate differentiae must of necessity be 
equal to the total number of indivisible species of 
animals. Thus, suppose M^e have some particular 
group of creatures whose prime differentiae are 
" pale " and " not pale " ; by that method these 
two will each give two other differentiae, and so 
forth, until in the end the indivisible differentiae are 
reached : these last ones will be either four in 



ttXtjOos tcov a<f)* ivos StTrAaCTta^o^eVcov rocravra he 
Kal TO, e'iSr]. 

("Eart S' Tj Sia(j)opa ev rfj vXr) ro elSos.^ ovre 
25 yap dvev vXt]? ouSev t,coov jjLopLov, ovre fiovq rj 
vXt]' ov yap Travrcos €xov aajfia eWat ^coov, ovSe 
Twv ixopicov ovBev, axJTrep ttoXXolkl? etprjraL.) 

"Ert Statpetv XPV '''^^^ ^^ '^fj oixrla Kal fir) roTs 

crvjJLPe^rjKOGL KaO^ avro, olov el rig ra G)(r]p^aTa 

SiaLpoLT), OTL ra /xev Svcrlv opOal? loas e;\;et ras 

so ycovta?, ra he TrXeioGiv GVfJb^e^rjKos yap tl rco 

Tpiyojvo) TO hvalv opdals taas exetv ras ywviag. 

"Ert rot? avriKeiixevois hiaipeZv {Set)/ hid(f>opa 
yap aAAT^AotS" ravriKeiiieva, olov XevKorrjg Kal fxe- 
Xavia Kal ev6vr7]s Kal KapLTryXonqs . eav ovv ddrepa 
hid^opa fjy rep avriKeipievcp hiaipereov , Kal pLT] ro 
35 fiev vevaei ro he ;!^/Dc6jLtaTt . TTpos he rovrois, ra y 
epuipvxo^ Tols KOLVols epyois rod acopiarog Kal rrjs 
643 b i/jvxT]?} OLOV Kal ev raZs prjOeiaaLS vvv TropevrcKa Kal 
Trnqva — eon yap riva yevq ols dpL(f)a) vTrdpxei Kal 
eon nrrjvd Kal aTrrepa, KaOdirep ro rwv pLvpynqKCDV 

^ sic Y : TO etSo? eV tt; vXtj vulg. 
2 <Set> supplevi. 

<* His point is that it is nonsensical to suppose that this 
numerical correspondence is bound to occur. 

* As at 641 a 18 ff. 

« See Met. 1025 a 30. 

<* These are enumerated in De sensu, 436 a 7 if., and Aris- 
totle seems here to be thinking of them as grouped together 
under the several faculties — nutritive, appetitive, sensory, 



number, or some higher value of 2" ; and there will 
be an identical number of species." 

(The species is the differentia in the Matter. There 
is no animal part which exists without matter ; nor 
on the other hand is there any which is matter only, 
for body in any and every condition cannot make an 
animal or any part of an animal, as I have often 
pointed out.^) 

(e) Again, the division ought to be made according 
to points that belong to the Essence of a thing and 
not according to its essential (inseparable) attributes. 
For instance, in making divisions of geometrical 
figures, it would be wrong to di\dde them into those 
whose angles are together equal to two right angles 
and those whose angles are together greater than two 
right angles ; because it is only an attribute of the 
triangle that its angles are together equal to two 
right angles.'' 

(f) Again, division should be by " opposites," 
opposites being mutually " different," e.g. pale and 
dark, straight and curved. Therefore, provided the 
two terms are truly " different," di\ision should be 
by means of opposites, and should not characterize 
one side by ability to s\\'im and the other side by 
some colour. And besides this, division of li\dng 
creatures, at any rate, by the functions which are 
common functions of body and soul,*^ such as we 
actually find done in the divisions mentioned above, 
where animals are divided into " walkers " and 
" fliers " — for there are some groups, such as that of 
the Ants, which have both attributes, being both 

locomotive, and thought (see De an. 414 a 28 ff.). His point 
is that the correct way to divide and classify animals is rather 
by bodily characteristics, which is what he himself does. 



643 b , X ^ , , n ' ' / ' 5 -\2 5 

yevos — Kau rco aypico /cat rjfjiepcp \ov oet) Otatpet- 

o9ai' cbaavTco<3 yap dv So^€t€ ravra e'lBr] hiaipeZv 

5 TTOLvra yap, co? elrreZvy ooa ruiepa Kal aypia rvy- 

XOLV€L ovra, olov dvOpajiroi, Ittttoi, ^oes, Kvves iv rfj 

^IvSlkyj, ves, alyes, Trpo/^ara* a)V eKaarov, el p.kv 

ofxcovv/JLOv, ov hirjprjrai ')(ojpis, el 8e ravra ev e'lhei, 

ovx olov t' etvai hiafj)opav ro aypiov /cat to T^p.epov. 

"OAco? 8' oTTOcaovv hia<j)opa^ pna hiaipovvri rovro 

10 ovjjL^aLveLv dvayKaXov. dXXd Set TreipdaOai Xap,- 
^dveiv Kara yevq rd ^coa, cos V(f)'^yr]v6^ ol ttoXXol 
hiopioavres opvidos yevos /cat l)(dvos. rovrcov 8' 
eKaarov TToXXaXs copiorai Siacjiopais, ov Kara rr)v 
SixorofJLLav. ovrco fjuev yap rjroi ro irapdnav ovk 
eun Xa^elv (rd avrd yap els rrXeiovs epLTTLTrrei 

15 8tatpea€t? /cat rd evavria els rrjv avr-qv), tj }xia 
pLovov hia(j)opd eorai, Kal avrr] rjroL dnXTJ i) e/c 
uvfJLTrXoKrjs rd reXevralov ear ai etSos". edv he p.rj 
SLa(f)opds XafjL^dvrj ns hia^opdv,^ dvayKolov, oioirep 
GvvSe(jp.cp rdv Xdyov eva rroiovvras, ovroj Kal rrjv 
SialpecTLV ovve)(fj TToie'lv. Xeyco 8' olov uvpL^aivei 

•20 rot? StatpovpLevoLs ro ptev drrrepov rd he rrrepcordv, 
TTrepojrov he rd piev jjpLepov ro 8' dypiov, tj ro /xev 

^ Kal EY : Kal toj vulg. 
2 supplevi. 

^ OTTOLavovv Sia^opav alii : o-noLaovv Y : Sta^opd vel 8(,a<f}opd 

* 8ia(f)opd A. ES : 8La<f)opav A. ttjs Sta^opa? P : Sta^opas' A. 
8La(f>opav Y ; rt? Peck : Tr]v vulg. 

« Cf. Plato, Politicus, 264 a 1. 

» On this see Piatt, C.Q., 1909, iii. 241. 

* For hLa<i)opd in the sense of " bifurcation " cf. Met. 
1048 b 4, where he speaks of the two " parts " of a hi.a(f>opd. 

^ i.e. with the preceding terms. See below, 644 a 5. 


" winged " and " wingless " — and by " wild " and 
" tame," " is not permissible, for this similarly would 
appear to divide up species that are the same, since 
practically all the tame animals are also found as 
^vild ones : e.g. Man, the horse, the ox, the dog (in 
India ^), swine, the goat, the sheep ; and if, in each 
of these groups, the wild and the tame bear the same 
name, as they do, there is no division between them, 
while if each group is specifically a unit, then it 
follows that " wild " and " tame " cannot make a 
valid differentiation.'' 

And generally, the same thing inevitably happens 
whatever one single line of differentiation is taken for 
the division. The proper course is to endeavour to 
take the animals according to their groups, fol- 
lowing the lead of the bulk of mankind, who have 
marked off the group of Birds and the group of Fishes. 
Each of these groups is marked offhyjuani/ cUjferentiae , 
not by means of dichotomy. By dichotomy (a) either 
these groups cannot be arrived at at all (because the 
same group falls under several divisions and contrary 
groups under the same division) or else there will be 
one differentia only, and this either singly or in 
combination ^ will constitute the ultimate species.* 
But (6) if they do not take the differeriiia of the differ- 
entia, they are forced to follow the example of 
those people who try to give unity to their prose by a 
free use of conjunctions : there is as little con- 
tinuity about their division. Here is an example 
to show what happens. Suppose they make the 
division into " wingless " and " winged," and then 
divide " winged " into " tame " and " wild " or into 

' And this will never completely represent any actual 
group or species. See below, 644( a 6 ff . 



643 b 

XevKov TO he (jLeXav ov yap hia(j)opa rod TrrepcoTOV 
TO jjfxepov ovSe to XevKov, dAA* ircpag apx"*] hca- 
(f)opa<s' €K€X 8e Kara avfil^e^rjKo?. Sto ttoXXols to 
€v evOeojs hiaiperiov, warrep XeyofJiev. koI yap 

25 ovT(x>s yiev at oreprjaeig ttoltigovgl 8ta<^opav, Iv Se 
rfj SL)(OTOjJLia ov TTOirjUOVcnv. 

"On 8' ovK evSex^raL rwv KaO* eKaarov elhaJv 
Xafi^dveiv ovSev hiaipovcn St;^a to yivos, woirep 
rives oj-qOriuav, /cat e/c rayvhe cfyavepov. 

'ASwaTov yap pilav vncipxeiv hia(f)opav rojv 

80 KaO^ eKacrrov hiaipercov, edv 0^ oLTrXd XajjL^dvr) ns^ 
idv re uvpLTreTrXeyiJieva' \Xey(x> he drrXa /xeV, edv firj 
exj) hiac^opdv, olov rrjv ux^^OTTohiav , ovpLTreTrXey- 
fieva he, edv exj], olov ro TToXvox^'hes Trpos to" 
Gxi'l>oTTOvvY rovro yap rj ovvex^^o, ^ovXerat roJv 
0.770 rov yevovs Kara rrjv hiaipeuiv hia(f)opa)v co? ev 

85 Tt TO 77av OV, dXXd napd rrjv Xe^iv crvfJi^aiveL hoKelv 
rrjv reXevraiav fJLovrjv elvac hia(f)opdv [olov ro ttoXv- 

644 a o";(tSes" t) ro hirrovv, rd 8' vttottovv /cat 7roAu770W 

TTepUpya'].^ on 8' a8uyaTOV rrXeiovs elvai roiavras, 
hrjXov del ydp ^ahil,a>v IttI rrjv eoxdrrjv hiacjiopdv 
d^LKveZrai [dAA' ovk errl rrjv reXevraiav /cat to 
et8os"]'^ ai;TT7 8' iarlv rj ro ox^^ottovv (jlovov, -^ 
5 TTaaa rj av/jLTrXe^us, edv hiaiprjrai dvdpojTTos,^ olov 
€L ns avvdeir] vttottovv, hiTTOVv, ox^^ottovv , el 8' 
rjv 6 dvdpcoTTOs axi'^oTTOvv jjlovov, ovnos eyiyver^ dv 
avrrj {tJ)' fila hia(f)opd. vvv 8' eTTeihr] ovk eaTtv, 

^ risY: om. viilg. ^ Trpos to) Piatt. 

' seclusi. codices varia, ut videtur; sic Bekker, 

* oloi' . . . TTcpUpya seclusi. 

^ dAA' . . . eiSos seclusi. 

• dvdpioTTov vulg. ' <i7> Ogle. 



" pale " and " dark " : neither " tame " nor " pale " 
is a differentiation of " winged," but the beginning 
of another line of differentiation, and can come in 
here only hy accident. Therefore, as I say, in dividing 
we must distinguish the one original group forthwith 
by numerous differentiae ; and then too the privative 
terms will make valid differentiae, which they will 
never do in the system of dichotomy. 

Here are further considerations to show that it is 
impossible to come at any of the particular species by 
the method of dividing the group into two, as some 
people have imagined. 

Obviously it is impossible that one single differentia 
is adequate for each of the particular species covered 
by the division, whether you adopt as your differentia 
the isolated term or the combination of terms ° (for 
this is intended by the continuity of the series of 
differentiae throughout the division from the original 
group, to indicate that the whole is a unity ; but, in 
consequence of the form of the expression, the last 
one comes to be considered as the sole differentia). 
And it is evident that there cannot be more than one 
such differentia ; for the division proceeds steadily until 
it reaches the ultimate differentia, and — supposing the 
division is aiming at " Man " — this is either " cloven- 
footed " alone, or else the whole combination, e.g. 
if one combined " footed," " two-footed," " cloven- 
footed." ^ If Man were merely a cloven-footed 
animal, then this would be the one differentia, arrived 
at by the right method. But as he is not merely 

" i.e. the last term of any series, or all its terms together, 
as he goes on to say. Cf. 643 b 15 f. 

* This definition appears also in Met. 1037-1038. 



644 a 

avdyKT] TToXkas elvat jir] vtto jxiav Siaipeaiv. dXXa 
ixrjv ttXclovs ye rod avrov ovk ecrrtv vtto fxiav 

10 St;^oro/xtav etvai, dAAa jLttav Kara filav reXevrdv. 
a)€rT€ dSvvarov otlovv Xa^elv tujv Kad^ cKaarov 
t,a)(jjv Slxol hiaipovyLevovs. 

IV. *A77oprjcr6t€ S' dv ng Sto. tl ovk dvcoOev eVt 
ovofian ifjLTrepiXa^ovTes dfia ev yevog dfjL(j)a> Trpoa- 
riyopevoav ol dvOpajnoL, o Trepiix^i rd re 'ivvhpa 

15 Koi rd TTTrjvd tojv ^cowv eart ydp eVta TrdOrj 
KOLvd Kal TOVTOLs [/cttt ToZs dXXoLS t^ois aTTaGLv]} 
dAA' dpLCjos 6p6d)s SnopLoraL rovrov rov rpoirov. 
oua fiev ydp StacfyepeL tojv yevchv KaO^ VTrepox'rjv Kal 
TO) [xdXXov Kal rjTTOVy^ ravra VTret^evKrai ivl yevei, 
dua 8' e;!^et to dvdXoyov, x^^jpis' Xeyco 8' olov opvis 

20 dpvidos hia(f)ip€L rw fiaXXov tj Kad^ vTrepox^jv (to 
fiev ydp fxaKpoTTTepov to he ^paxvTTTepov) , IxOves 
8* opviOog TO) dvdXoyov (o ydp eKeivco TTTepov, 6a- 
repo) XeTTLs). tovto 8e TTOielv IttI TrdoLV ov pdhiov 
rd ydp TToXXd ^cpa dvdXoyov rauro TreirovOev. 

'Ettci 8' ovGiaL jjiev elui rd eoxo-Ta etSr], /card 

25 8€ TavTa Td^ TO clSos dhid^opa (olov TtWKpdTT)?, 
KopLGKOs), dvayKaXov ^ rd KaOoXov virdpxovTa 

^ seclusi Ogle docente. 

^ sic Rackham : to fiaXXov /cat to (to om. Y) ■^ttov vulg. 

^ Kara 8e ravra ra Peck : ravra 8e Kara vulg. 

** This paragraph has been corrupted by confusing inter- 
polations, which I have bracketed in the Greek text and 
omitted in the translation. With this passage cf. Met. 
1037 b 27—1038 a 30. 

'' On this point see D'Arcy W. Thompson, Growth and 
Form, esp. ch. 17, and the same author's paper Excess 
and Defect ; or The Little More and the Little Less, in 
Mind, xxxviii. (N.S.) 149, pp. 43-55. See also infra, 
661 b 28 ff., 692 b 3 ff . ; and Introduction, p. 39. 


PARTS OF ANIMALS, I. iii.-iv. 

that, it is necessary that there should be many 
differentiae^ not under one hne of division. And yet 
tliere cannot be more than one differentia for the same 
thing under one hne of dichotomy : one hne must end 
in one differentia. So it is impossible for those who 
follow the method of twofold division to arrive at any 
of the particular animals.** 

IV. Some may find it puzzling that general usage 
has not combined the water-animals and the feathered 
animals into one higher group, and adopted one name 
to cover both, seeing that in fact these two groups 
have certain features in common. The answer is that 
in spite of this the present grouping is the right one ; 
because while groups that differ only " by excess " 
(that is, "by the more and less " ^) are placed 
together in one group, those which differ so much 
that their characteristics can merely be called ana- 
logous are placed in separate groups. As an illus- 
tration : (a) one bird differs from another bird ** by 
the more," or " by excess " : one bird's feathers 
are long, another's are short ; whereas (6) the 
difference between a Bird and a Fish is greater, 
and their correspondence is only by analogy : a fish 
has no feathers at all, but scales, which correspond 
to them. It is not easy to do this in all cases, for 
the corresponding analogous parts of most groups of 
animals are identical. 

Now since the ultimate species are " real things," ^ Method* 
while within them are individuals which do not differ 
in species (as e.g. Socrates and Coriscus),^ we shall 
have to choose (as I have pointed out) ^ between 

*' Lit. " substances," 

' i.e. within the species " man." 

• Above, at 639 a, b, etc. 



TTporepov €L7T€lv t) 77oAAaK'ts" TavTov XeyeLVy Kaddirep 
eipTjTai. (to. 8e KaOoXou Koiva' ra yap TrXeioaiv 
VTTapxovra KadoXov Xiyojxev.) aiTopiav 8' e^^i rrepl 
TTorepa Set Trpaypiareveodai. ^ [ikv yap ovoia to 
80 rep elhei a.Top.ov, KpariGTOV, et rt? Sm'airo, Trepl tojv 
Kad' €KaGT0V Kol drofjLOJv to) etSet Oecjopelv ^copis, 
wcrnep Trepi dvdpwTTOv, ovtoj Kal^ nepl opvidos, (jcal 
fjLTj TTepl orovovv opvidos} {^X^^ y^P ^'^^1 '^^ yevos 
TOVTo), dXXd TTepl TOJV drofxcDV^ olov tj orpovOos r] 
yepavos t] tl tolovtov. ^ Se GvpL^ijaeraL XeyeLV 

35 77oAAaACtS' TTepl TOV aVTOV TTddoV? Sid TO KOLvfj 

TTXeioGiv vvdpx^iv, ravrrj 8' icrrlv VTrdroTTOV Kal 
Bi^h P-OLKpov TO TTepl eKdoTov XeyeLV xcopls' lgcjs fiev 
ovv opdcog ex^i Ta puev Kara yevT) Koivfj Xeyeiv, 
oca XeyeTai KaXojg ojpLopievojv tcjv dvOpayTTCUv, Kal 
ex^i re p.iav cpvatv Koivrjv Kal e'chr] ev avTols^ prj 
6 TToXv hieGTcx)Ta, opvis Kal IxOvs, Kal ei tl dXXo 
cgtIv dvcovvfJiov jLteV, tco yeveL 8' o^ota* TrepLex^L 
TO, iv avTO)^ e'lSr]- ooa 8e p,rj rotaura, Kad* 
CKaGTOv, olov TTepl dvBpcjTTov Kal el tl tolovtov 
€Tep6v eOTLV. 

l^X^^^^ ^^ '^^'■S' <j;^7^/xacrt tojv pLopiojv Kal tov 
o-cujLtaro? oXov, edv ofJLOLOTrjTa excocr^v, ojpLGTaL to, 

yevT], OLOV to tojv op] 


yevo? TTpos avTO ttc- 

^ Kal] fjLT) Bonitz. 

* hunc locum correxi, S secutus ; l;^€i yap etBr] to y4vos 
TOVTO- aXXa TTepl otovovv opviOos rtSi' arop-Oiv, olov ktX. vulg. 

^ avToU vulg'. : correxi. * ofxoiojs vulg. : correxi. 

' avTw vulg. : correxi. 

* avTo Piatt, fortasse Z^ : auro Y : avTo. Z^, vulg. 



describing first of all the general attributes of many 
species, and repeating the same thing many times 
over. (By " general " attributes I intend the 
" common " ones. That which belongs to many we 
call " general.") One may well hesitate whether of 
the two courses to follow. For, in so far as it is the 
specifically indivisible which is the " real thing," it 
would be best, if one could do it, to study separ- 
ately the particular and specifically indivisible sorts, 
in the same way as one studies " Man," to do this 
with " Bird " too, that is, to study not just " Bird " 
in the mass, but — since " Bird " is a group which 
contains species — the indivisible species of it, e.g. 
Ostrich, Crane, and so on. Yet, on the other hand, 
this course is somewhat unreasonable and long- 
winded, because it makes us describe the same attri- 
butes time and again, as they happen to be common 
attributes of many species. So perhaps after all the 
right procedure is this : (a) So far as concerns the 
attributes of those groups which have been correctly 
marked off by popular usage — groups which possess 
one common nature apiece and contain in themselves 
species not far removed from one another, I mean 
Birds and Fishes and any other such group which 
though it may lack a popular name yet contains 
species generically similar — to describe the common 
attributes of each group all together ; and (6) with 
regard to those animals which are not covered by 
this, to describe the attributes of each of these by 
itself — e.g. those of Man, and of any other such species 
there may be. 

Now it is practically by resemblance of the shapes 
of their parts, or of their whole body, that the groups 
are marked off from each other : as e.g. the groups 



644 b 

10 TTOvde /cat ro rcjv lxOvojv Kal ra jLtaAa/cta re /cat 

TO, ourpeia. ra yap jLtopta Sta</)epor;crt tovtojv ov 

rrj dvdXoyov oiiolottjtl, olov ev dvdpcoTrci) Kal i-)(dvL 

7T€.7Tov9ev oGTOvv TTpos OLKavOav, dXXd fidXXov rot? 

GcofjLaTLKoXs ndOeaLV, olov jjueyedei pLLKponqri, /xaAa- 

16 KorrjTL UKXriponqTiy XeioT-qri rpa-)(yrr]TL Kal roZs 
TOLOVTOiSi oXojg 8e to) /xaAAov /cat rjrTOV. 

nto? /xev ovv diTohex^Gd ai Set Tr]v nepl ^ucreca? 
jjLedoSov, Kal TLva rponov yivoir^ dv rj deojpua rrepl 
avrayv oSoj Kal pacrra, ert be irepl Siaipeaecjos, riva 
rpoTTOV ivbex^rai pLerLovcn Xafx^dveLv xPV^^t^^^y '^^'' 

20 Stort TO Sixorofielv rfj pikv dhvvarov rfj 8e K€v6v, 
elpr]Tai. hLOjpLGfJLevcov Se tovtojv irepl ra)v i(f)€^7Js 
Xeyojfxev, dpxr]V riqvhe TTotrjudpievoL. 

V. Toil' ovGidJv ooai (f)V(J€i ovveGTaai, rds fxev 
(Xeyo[JL€vy^ dyev^Tovs Kal dcfjOdprov? elvai rov 
aTTavra alcova, rag Se jj.erex^t'V yeveueojs Kal 

25 (f)dopds. ovfjLJ3el3rjKe Se nepl fiev eKeivas Tt/xta? 
ovaag Kal 9eias iXdrrovs rjjjLlv vTrdpx^tv deajpias 
(/cat yap i^ aJv dv rts" OKeipairo irepl avrcov, Kal 
TTcpl Sv etSeVat rroOovfJieVy TravreXco? iarlv oXiya rd 
(fyavepd Kara rr]v aLuOrjaLv), rrepl he rd)v (f)dapTd)v 
<f)vrdjv re Kal t^ojcxjv eviropovfjiev fiaXXov irpos rrjv 

80 yvchoiv hid rd Grvvrpo(f)OV' ttoAAo. ydp rrepl eKaarov 
yevos Xd^oL rt? dv rwv VTrapxdvrojv jiovXopievos 
hiaiToveZv CKavcog. ex^i S* eKdrepa xdpiv. rcov fiev 
ydp el Kal /caret fiCKpov ecfyaTTrofieda, o/xcos" hud rr]V 

^ (Xeyofiev) Peek. 

*• Lit., " softies." The group includes, roughly, the 
cephalopod moUusca. 

" Lit., " oysters " (bivalves). 



Birds, Fishes, Cephalopods," Testacea.^ Within each 
of these groups, the parts do not differ so far that they 
correspond only by analogy (as a man's bone and a 
fish's spine) ; that is, they differ not structurally, but 
only in respect of bodily quahties, e.g. by being 
larger or smaller, softer or harder, smoother or 
rougher, and so forth, or, to put it generally, they 
differ " by the more and less." 
We have now shown : 

(1) how to test a method of Natural science ; 

(2) what is the most systematic and easiest way of 
studying Natural science ; 

(3) what is the most useful mode of Division for 
our present purpose ; 

(4) why dichotomy is in one respect impossible and in 
another futile. 

Now that we have made this beginning, and clearly 
distinguished these points, we may proceed. 

V. Of the works of Nature there are, we hold, two Aprotreptic 
kinds : those which are brought into being and perish, oflnfmais'?^ 
and those which are free from these processes through- 
out all ages. The latter are of the highest worth and 
are divine, but our opportunities for the study of 
them are somewhat scanty, since there is but little 
evidence available to our senses to enable us to con- 
sider them and all the things that we long to know 
about. We have better means of information, however, 
concerning the things that perish, that is to say, plants 
and animals, because we live among them ; and any- 
one who will but take enough trouble can learn 
much concerning every one of their kinds. Yet 
each of the two groups has its attractiveness. For 
although our grasp of the eternal things is but 
slight, nevertheless the joy which it brings is, by 



644 b 

TiixioTTiTa Tov yv(jjpil,eiv rjhiov 7) ra Trap rjfXiV 

airavra, cooirep /cat rcjv epojfievcjjv to tvxov koI 
35 [XLKpov pLopiov KaTiSelv T^'Stov IcFTiv 7] TToWa ere pa 

645 a /^^ctt [leydXa 8t' aKpi^eias ISelv ra 8e Sta to juaAAov 

/cat TrXelco yvojpLt,eLV avrcov Aa^jSavet tt^v rrjg eVt- 
onqixr]^ vnepox^v, en Se 8ta ro TrXtjaiaLrepa rjfjLwv 
etvai /cat rr^? (f)V(jea>s oLKeiorepa ayrt/caraAAcir- 
rerai n Trpos ttjv Trepl ra dela (^iAo(TO(/>tW. CTiet 

5 he nepL eKetvcov hir]\9oyLev Xeyovres ro (ffatvojJLevov 
'^[juv, XoLTTOv Trepl rrjg Joji/ctJ? </)Ucreaj? etVetv, fx-qSev 
TTapaXiTTOvras eh SvvafXiv jLt^jre arijiorepov puiqre 
TLfJLLcorepov. /cat yap eV rot? jLtT] Kexo-pioiievoLs 
avrojv rrpos rr]V ato-OrjOLV Kara rrjv Oeojpiav ofiCDS^ 
7] hrnxiovpyqaaoa (J)vgl? ajJL'qxdi'OV? rjSovdg Trapexet 

10 rot? SvvajjievoLg rds alrias yvcopLl,eiv /cat (jivoei 
(^tAocro^ot?. Kalyap av e'er] rrapaXoyov /cat aroiroVy 
el rds jLtev et/cova? avrwv Oecopovvres ;^atpo^€v on 
TTjV hriiiLovpyr](jaoav rexvr]v ovvdecopovfxev, olov rT)v 
ypacjiLKrjv i) rrjv TrXaonK-qv, avrojv Se rojv <^voei 
GVvearojriDV {jltj fiaXXov dyarraypiev rr)V deajplav, 

15 SvvdpevoL ye ra? alrias Kadopdv. 8to Set (irj 
SvGX^poLLveLV TTaiSiKcJos rTjV Trepl rojv anporepa)v 
l,cpa)V eTrioKeifjiv ev Trdoi yap rot? (j>voiKols eveori 

^ o/Lio;? Bekker : ofiolcos codd. 

" This passage, 645 a 6-15, is quoted by R. Boyle {0/ the 
Usefulnesse of Naturall Philosophy^ 1663) both in Gaza's 
Latin version and in an English translation, and he intro- 
duces it thus : " And, methinks, Aristotle discourses very 
Philosophically in that place, where passing from the con- 
sideration of the subliniist productions of Nature, to justifie 
his diligence in recording the more homely Circumstances of 
the History of Animals, he thus discourses." He also quotes 


reason of their excellence and worth, greater than 
that of knowing all things that are here below ; just 
as the joy of a fleeting and partial glimpse of those 
whom we love is greater than that of an accurate 
view of other things, no matter how numerous or how 
great they are. But inasmuch as it is possible for us 
to obtain more and better information about things 
here on the earth, our knowledge of them has the 
advantage over the other ; and moreover, because 
they are nearer to us and more akin to our Nature, 
they are able to make up some of their leeway as 
against the philosophy which contemplates the things 
that are divine. Of " things divine " we have al- 
ready treated and have set down our views concerning 
them ; so it now remains to speak of animals and 
their Nature. ° So far as in us lies, we will not leave 
out any one of them, be it never so mean ; for though 
there are animals which have no attractiveness for 
the senses, yet for the eye of science, for the student 
who is naturally of a philosophic spirit and can dis- 
cern the causes of things. Nature which fashioned 
them provides joys which cannot be measured. If we 
study mere likenesses of these things and take pleasure 
in so doing, because then we are contemplating the 
painter's or the carver's Art which fashioned them, and 
yet fail to delight much more in studying the works 
of Nature themselves, though we have the ability to 
discern the actual causes — that would be a strange 
absurdity indeed. Wherefore we must not betake 
ourselves to the consideration of the meaner animals 
with a bad grace, as though we were children ; since 
in all natural things there is somewhat of the mar- 

the following passage, a 15-23, describing it as " that Judicious 
reasoning of Aristotle." 

D2 99' 



TL OavfiaoTov Kal KaOaTrep 'YipaKXecrog Xeyerai 

20 TTpos Tous ^ivovs eliT^lv Tovg povXoiJL€vov9 ivTVX^^v 
avTO), ot €7T€LSr] TTpocTLovreg elSov avTov depofievov 
Trpog TO) Ittvo) eGTTjGav [eKeXeve yap avrovs etVteVat 
Oappovvras' elvai yap Kal ivravOa Oeov^), ovtco /cat 
TTpos Tr]v ^-qrrjaLV rrepl eKaarov rcov ^cocuv TrpouUvai 
Set ixri hvG(x)7TOV}X€voVy d>s eV airaaiv ovros tlvos 
(f)vcnKov Kal KaXov. 

To yap fjLTj TVxovTCos dAA' evcKo, tlvos eV rot? tt^s" 

2.1 (f)va€a>s epyoLs earl Kal fxaXiara' ov 8' eVe/ca 
ovveoTTjKev t) yeyove rlXovs, ttjv tov KaXov ;^ojpav 
€LXrj(f)€V. el 8e rts" rrjv rrepl rcov dXXwv ^cp(x)V 
decopiav dnpLov etvat vevofiLKe, tov avTov Tponov 
oteaQaL XPV '^^'' '^^P^^ avTOV' ovk eoTL yap dvev 
TToXXrjg Svax^peia? tSetv e^ Sv avveGTTjKe to tojv 

80 dvdpcjTTOJV yevoSy olov at[jLa, udpKes, octtcl, cfiXe^es 
Kal ra rotaOra pLopta. opLolcos Te Set vo/xt^etv tov 


AeyojLtevov fjurj Trepl ttjs vXrjs Trotetcj^at ttjv puvqix-qv, 
firjSe TavTTjg x^P^^> <^AAa Trj? oXrjg piopcfirjs, olov Kal 
7T€pl OLKias, dXXd pLTj ttXlvOojv Kal TTYjXov Kal ^vXojv 
85 Kal TOV 7T€pl (f)VG€OJ£ TTepl TTjS ovvOeuecos Kal TTJg 
oXrjs ovGias, dXXd purj rrepl tovtcdv a jjlt] GvpL^alvei 
XOJpi^opievd TTOTe ttjs ovocas avTcov. 

<* Or, with reference to another use of ovala, " which gives 
them their being." Independent approaches to the position 
that components are non-significant in isolation had been 
made, e.g. by Anaxagoras, as a physical philosopher (see 
my article in C.Q. xxv. 27 ff., 112 ff.), who held that " the 
things (i.e. the constituent elements) in this world are not 
separate one from another" (frag. 8, Diels, Fragmented ^ 



vellous. There is a story which tells how some 
visitors once wished to meet Heracleitus, and when 
they entered and saw him in the kitchen, warming 
himself at the stove, they hesitated ; but Heracleitus 
said, " Come in ; don't be afraid ; there are gods 
even here." In like manner, we ought not to hesi- 
tate nor to be abashed, but boldly to enter upon our 
researches concerning animals of every sort and kind, 
knowing that in not one of them is Nature or Beauty 

I add " Beauty," because in the works of Nature 
purpose and not accident is predominant ; and the 
purpose or end for the sake of which those works have 
been constructed or formed has its place among what 
is beautiful. If, however, there is anyone who holds 
that the study of the animals is an unworthy pursuit, 
he ought to go further and hold the same opinion 
about the study of himself, for it is not possible 
without considerable disgust to look upon the blood, 
flesh, bones, blood-vessels, and suchlike parts of 
which the human body is constructed. In the same 
way, w^hen the discussion turns upon any one of the 
parts or structures, we must not suppose that the 
lecturer is speaking of the material of them in itself 
and for its ovm sake ; he is speaking of the whole 
conformation. Just as in discussing a house, it is the 
whole figure and form of the house which concerns us, 
not merely the bricks and mortar and timber ; so in 
Natural science, it is the composite thing, the thing 
as a whole, which primarily concerns us, not the 
materials of it, which are not found apart from the 
thing itself whose materials they are." 

59 B 8) ; also from the logical point of view, as seen in 
Plato, Theaetetus, 201 e ff. 



645 b ^AvayKalov 8e Trpcorov ra avjJL^e^rjKora SieXelv 
Tvepl eKaoTOV yevos, oaa Kad^ avra TrdoLv vnapx^L 
rot? t,a)OLSy fJLeTOL he ravra ras alrias avrcbv TTeipd- 
(jdai SteAetv. etprjraL fxev ovv /cat Trporcpov on 
TToXXa Koiva TToXXols VTTapx^i rajv l^wcov, ra fiev 
olttXcos {olov TToSes, 7TT€pd, XeTTiSes, Kal ttolOt] St) 
rov avTov rpoTTOV tovtols), ra S' dvdXoyov {Xeyco 8' 
dvdXoyov , on roTs p^^v vrrdp^ei vXevpLOJv, rdls Se 
TrXevpLCDV pL€V oVy o he rols e)(ovoi nXevpova, eKel- 
VOL9 irepov dvrl rovrov Kal rots' /xev at/xa, rots' 8e 

10 TO dvdXoyov rrjv avrrjv €xov Svvap.iv rjvnep tols 
ivalpLOis TO alpLo)' to 8e Aeyetv x^P^^ Trepl eKdarcov 
TU)v Kad^ eVaara, Kal epiTrpoodev etVo/Ltcv ort 
TToAActKts' Gvp^^rjoerai ravra Aeyetv, eVetSav Ae- 
ycopLev 7T€pl Trdvrcov rcov VTTapxovrcnv vndpx^i 8e 
TToAAotS' ravrd. ravra pL€v ovv ravrrj SLCoploOaj. 

15 'Evret 8e ro pcev opyavov Trdv eveKd rov, rcov 8e 
rod oojpLaros pLopiojv eKaarov eveKd rov, ro 8' ov 
eveKa Trpd^is ns, (f)avep6v on Kal ro ovvoXov acJjpLa 
GvveGrrjKe irpd^eajs nvog eveKa ttoXv pie pods. ^ ov 
yap Tj TTpicTis rod TTpiovos X^P^^ yeyovev, dAA' o 
TTpLWV TTJs TTpioeajs' xpT^CTts' ydp ns rj TrpiuLs euriv. 
ware Kal ro acopid ttcos ttjs iJjvx'^? eveKev, /cat ra 

20 pLopia rojv epycjv npos a 7Te(f)VKev eKaorov. 

AeKTeov dpa Trpcorov rds irpd^eis ras re Koivds^ 

^ TToXvfMepovs P : 7tXi]povs ■vulg. : fortasse TToXvfx6p(f)ov, c£. 
646 b 15. 

2 TTavTcjov post KOLvas viilg. ; delevi. 

• Almost always used in the singular by Aristotle. 

'' By " blood " Aristotle means red blood only. " Blooded " 
and " bloodless " animals do not quite coincide with verte- 
brates and invertebrates ; for there are some invertebrates 
which have red blood, e.g. molluscs (Planorbis), insect 


First of all, our business must be to describe the Final 
attributes found in each group ; I mean those of the 
" essential " attributes which belong to all the -^i^^thod. 
animals, and after that to endeavour to describe the 
causes of them. It will be remembered that I have 
said already that there are many attributes which 
are common to many animals, either identically the 
same {e.g. organs like feet, feathers, and scales, and 
affections similarly), or else common by analogy 
only {i.e. some animals have a lung," others have no 
lung but something else to correspond instead of 
it ; again, some animals have blood, while others have 
its counterpart,^ which in them has the same value 
as blood in the former). And I have pointed out 
above that to treat separately of all the particular 
species would mean continual repetition of the 
same things, if we are going to deal with all their 
attributes, as the same attributes are common to 
many animals. Such, then, are my views on this 

Now, as each of the parts of the body, like every 
other instrument, is for the sake of some purpose, 
viz. some action, it is evident that the body as a 
whole must exist for the sake of some complex 
action. Just as the saw is there for the sake of 
sawing and not sawing for the sake of the saw, 
because sawing is the using of the instrument, so in 
some way the body exists for the sake of the soul, 
and the parts of the body for the sake of those 
functions to which they are naturally adapted. 

So first of all we must describe the actions (a) 

larvae (Chironomiis), worms (Arenicola). In other in- 
vertebrates the blood may be bhie (Crustacea) or green 
(Sabellid worms), or there may be no respiratory pigment 
at all (most insects). 



645 b 

Kal rots' Kara yevos koI ra? /car* efSoj. Aeyco Se 
KOLvas {lev at TraGiv v7Tdp)(0VGi rdls ^cools, Kara 
yevos Se ocrojv Trap' aXXrjXa rag Sia(f)opa9 opcjiiev 

25 KaB^ v-nepo-xr^v ovoas, olov opviOa Xeyco Kara yevos, 
dvOpcjOTTOv Se Kar* ethos, Kal Trdv o Kara rov 
KaOoXov Xoyov firjhejJLiav ep^et Siacfyopdv. ra {JLev 
yap e)(ovaL to kolvov Kar dvaXoyiav, rd §€ Kara 
yevos, rd he Acar' elhos. 

"Ooai fiev ovv irpd^eis aAAcov eveKa, hrjXov on, 
Kal CUV at TTpd^ets rov avrov rpoirov hieordoLV 

30 ovirep at Trpd^ecs. opioiws he Kav el rives Trporepai 
Kal reXos erepcov Trpd^ewv rvyxdvovonv ovoai, rov 
avrov e^ei rpoirov Kal rcov jxopicov eKaarov wv at 
npd^eis at roiavraf Kal rpirov, a nvojv^ bvrcov 
dvayKalov VTrdpx^eiv . {Xeyco he Trddrj Kal rrpd^eis 
yeveoiv, av^rjaiv, o;^etav, eyp-qyopcnv, vttvov, tto- 

35 peiav, Kal ottog* aAAa roiavra rols t^cpois vnapx^i' 
fiopia he Xeyo) plva, o(f)daXpi6v Kal ro avvoXov 
S^6 a. TTpoacoTTOV, ajv eKaarov KaXeXrau fieXos. opLOLOJS 
he Kal rrepl rcov dXXwv.) 

Kat TTepl [lev rod rpoTTOV rrjs [ledohov roaavO* 
riplv elpT^adco' rds S* air las Tre LpaOcofiev eiTrelv irepi 
re rcov kolvcjv Kal rcov Ihicov, dp^djievou, KaOdirep 
hiajpLaajiev, irpcorov dno rcov npcorcov. 

^ a Tivtov Peck, cf. 677 a 18: cov vulg. : a tovtcov Ogle. 

" See above, note on 644 a 17. 
* Examples will occur during the course of the treatise. 



which are common, and those which belong (6) to a 
group, or (c) to a species. By " common " I mean 
those that are present in all animals ; by " those 
which belong to a group " I mean those of animals 
whose differences we see to be differences " of 
excess " " in relation to one another : an example of 
this is the group Birds. Man is an example of a 
species ; so is every class which admits no differ- 
entiation of its general definition. These three sorts 
of common attributes are, respectively, (1) analogous, 
(2) generic, (3) specific. 

Now it is evident that when one action is for the 
sake of another action, then the instruments which 
perform the two actions differ exactly as the two 
actions differ : and if one action is " prior " to another 
and is the " end " of that other action, then the part 
of the body to which it belongs wdll be " prior " to 
the part to which the other action belongs. There 
is also a third possibility, viz. that the action and its 
organ are there simply because the presence of others 
necessarili) involves them.^ (By affections and actions 
I mean Generation, Growth, Copulation, Waking, 
Sleep, Locomotion, and the other similar ones that 
are found in animals. Examples of parts are : Nose, 
Eye, Face ; each of these is named a " limb " or 
" member." And the same holds for the rest too.) 

Let this suffice concerning the method of our 
inquiry, and let us now endeavour to describe the 
causes of all these things, particular as well as 
common ; and, according to the principles laid down, 
we will begin with the first ones first. 



hiK TLVCjJV fJLev ovv fxopLOJV Kai TToaojv avv 

earrjKev eKaurov raJv t,a)OJV, iv rats iGTopiaLs rats 

10 Tvepl avrcbv BeS't^Xajrat oa^iorepov' 8t' as S' alrias 

€Kaarov tovtov e^^i rov rpoTTOV, eTTiGKeTrriov vvv, 

Xcoplaavras KaO^ avra rcov iv rals laropiais etpTj- 

Tpi(ji)v 8' ovocbv TcDv (jvvdeueojv Trpcorrjv fiev dv 
TLS delrj TTjv eK rcov KaXovpLevcov vtto tlvojv oroi- 
X^LCov, OLOV yrj9, aepos, vSaros", irvpos. en 8e 

15 ^eXrtov tocos e/c tcqv hvvdfiecov Xeyetv, /cat tovtojv 
ovK i^ OLTTaacoVy dAA' oiairep iv irepois eipr^rai /cat 
TTporepov vypov yap /cat $rjp6v /cat depp.6v /cat 
ipvxpov vXt] rdJv ovvOercov aajfidrajv icrrlv, at 8' 
aAAat 8ta^opat Taurats" aKoXovOovaiv, olov ^dpos 
/cat Kov^OTiqs /cat ttvkvottjs /cat {JLavorrjs /cat rpa- 

20 x^'^V^ '^^^ AetoTT^s" /cat rdXXa rd roiavra irddr] twv 
acopLdrajv. Sevrepa 8e avaraois €/c rcbv TrpcarcDV -i^ 

TcDv 6pL0L0fji€p<JL)V (jiVGlS iv Tols ^CpOLS icTLV, oloV 

OOTOV /cat uapKos /cat rcov dXXcov rcjv TOLOVTa)v. 

" For the threefold series cf. Be gen. an. 714 a 9 ff. This 
first " composition " seems to be intended to cover non- 
organic compounds. 

* " Dynamis " here is clearly the pre-Aristotelian technical 
term. See Introduction, p. 30. "^ See De gen. et corr. chh. 2, 8. 

''In some contexts, " fluid " and " solid " seem more 


I HAVE already described with considerable detail P'lrpose and 
in my Researches upon Animals what and how many the treatise. 
are the parts of which the various animals are 
composed. We must now leave on one side what 
was said there, as our present task is to consider 
what are the causes through M'hich each animal is as 
I there described it. 

Three sorts of composition can be distinguished. 
(1) First of all '^ we may put composition out of the 
Elements (as some call them), viz. Earth, Air, Water, 
Fire ; or perhaps it is better to say dynameis ^ instead 
of Elements — some of the dynameis, that is, not all, 
as I have stated pre\-iously elsewhere.'^ It is just 
these four, the fluid substance, the solid,*^ the hot, and 
the cold, which are the matter of composite bodies ; 
and the other differences and qualities — such as 
heaviness lightness, firmness looseness, roughness 
smoothness, etc. — which composite bodies present 
are subsequent upon these. (2) The second sort of 
composition is the composition of the "uniform"* 
substances found in animals (such as bone, flesh, 
etc.). These also are composed out of the primary 

appropriate : in others, " moist " and " dry " (the traditional 
renderings). Aristotle defines them at De gen. and corr. 
329 b 30. See also below, 6-1-9 b 9. I have normally trans- 
lated them " fluid " and " solid " throughout. 

• " Uniform," " non-uniform"; see Introduction, p. 28. 



646 a ^ 

TpiTT] he Kal reXevrala /car' dpLOfiov rj rajv dv- 


25 'E-TTet 8' ivavTLOJS inl rrjs yeveaeojs e;^et /cat ttJ? 
ovaias — ret yap varepa rfj yevioei Trporepa ttjv 
^UCTtv ioTi, /cat TTpcoTOV TO rfj yeveaeu reXevraiov 
{ov yap ot/cta ttXlvOcov eVe/ceV ecrrt /cat Xidojv, dAAa 
ravra rrjs ot/cta? • ojjlolws 8e rovr e;)^et /cat Trept tt^v 
dAAr^v vXrjv ov jjlovov 8e (f)avep6v on rovrov e)(€.i rov 

80 TpoTTOV e/c TTJ? iTTayojyrjs, dXXa /cat /caret rov Aoyov 
77av yd/) TO ytvo/xevov e/c rtvos" /cat els' rt vrotetrat 
TTjv yeveoLV, /cat dyr' otpxy]? ctt* apx^jv, 0.776 ttjs 
TrpojTiqs KLVovoris /cat i)(ovor]s tJStj rivd (f)VGLV CTrt 
Ttva jLto/j^T^y 7) TOLOVTOV dXXo reXos' dvdpojTTOs yap 
dvOpojTTov /cat <J)vt6v yewa <J>vt6v e/c tt]? Trept 

85 EKaarov VTTOKeLjjLevrjs vXrjs) — rep fxkv ovv XP^^^ 
646 b Trporepav rrjv vXtjv dvayKaXov etvat /cat rrjv yeveaiv, 
rep Xoycp 8e rrjv ovoiav /cat T17V eKacrrov fjLopejiTjv. 
SrjXov 8' dv Aeyi^ rt? rov Aoyov tt^S" yeveoecos' 6 [xev 
yap rrjs OiKoSofirjaecos Aoyo? e;\;et rov rrjs olKLas, 
6 8e TT^S" OLKLas ovK e;^et rov rjjs olKohopLTjoccos. 
5 opioiajs Se rovro avp^e^rjKe /cat eVt rtuv dAAojv. 
wore rrjv pL€V rcjv Groixeioov vXrjv dvayKalov etvat 
rojv 6pLOLop.epa)v eVe/cev varepa yap e'/cetVcov ravra 

" Or, " efficient." 

^ Or, " in thougrht," " in conception." 

• Almost represented here by " definition.** 



substances. (3) The third and last is the composition 
of the " non-uniform " parts of the body, such as 
face, hand, and the Hke. 

Now the order of things in the process of formation 
is the reverse of their real and essential order ; I 
mean that the later a thing comes in the formative 
process the earlier it comes in the order of Nature, 
and that which comes at the end of the process is at 
the beginning in the order of Nature. Just so bricks 
and stone come chronologically before the house, 
although the house is the purpose which they sub- 
serve, and not vice versa. And the same applies to 
materials of every kind. Thus the truth of my state- 
ment can be showTi by induction ; but it can also 
be demonstrated logically, as follows. Everything 
which is in process of formation is in passage from 
one thing towards another thing, i.e. from one Cause 
towards another Cause ; in other words, it proceeds 
from a primary motive °' Cause which to begin with 
possesses a definite nature, towards a Form or an- 
other such End. For example, a man begets a man 
and a plant begets a plant. These new indi- 
viduals are made out of the substrate matter appro- 
priate in each case. Thus, matter and the process 
of formation must come first in time, but logically^ 
the real essence and the Form of the thing comes 
first. This is clear if we state the logos ^ of such a 
process. For example, the logos of the process of 
building includes the logos of a house, but that of a 
house does not include that of the process of building. 
And this holds good in all such cases. Hence we 
see that the matter, viz. the Elements, must exist 
for the sake of the uniform substances, because 
these come later in the process of formation than 



648 b ^ , / c- \ \ > ^ ^ \ 

TT] yeveaei, tovtojv be ra avofjiOLOfiepr]. ravra yap 

Tjhrj TO reXos e^et xrat to Ttepas, ivl rod rpirov 

Xa^ovra ttjv ovGraoLV dpidfjiov, Kadamep €7tl ttoXAcov 

10 GVfjL^alveL TeXeiovaOaL ras yevecrcts'. 

'E^ d[Ji(f)OTepojv jJLev ovv rd ^cool avvearrjKe rcov 
yiopiiov TOVTCov, dXXd rd opLOLOfxeprj ra)v dvo/xoto- 
ixepayv eVe/ceV ionv iKeivojv ydp epya Kal Trpd^eis 
eloivy olov 6^daXp.ov Kal fJLVKrrjpos Kal rod TTpoG- 
OJTTOV rravrds Kal haKrvXov Kal )(^€ip6s Kal rravros 

15 rod ^paxi-ovos . 7ToXvfji6p(f)a)v Sc rcbv irpd^eoiv /cat 
rix)V KLVT](7€a>v VTTapxovowv rols t,a)ois oXols re Kal 
rols jJLopiOLS roLS roiovrois, dvayKalov ef Sv avy- 
Keivrai rds hwajxeis dvofjiota? ex^LV Tvpo? fX€v ydp 
riva pLaXaKorrjs XPW^H'^^ Trpds Se nva GKXr]p6rr]s , 
Kal rd fjb€v rduiv e;^etv Set ra Se Kapupiv. 

20 To, jLtev ovv ofiOLopueprj Kard fxepog StctAr^^e rds 
SwdpLets rds roiavras {to puev ydp avrcov iom 
pbaXaKov rd he oKXiqpov, Kal rd [j,€V vypdv rd 8e 
^iqpov, Kal rd [Jiev^ yXiGXpov rd Se Kpavpov), rd 
8' dvoixoLOjJLeprj Kard rroXXds Kal avyKeipiivas 
dXXr]Xais' irdpa ydp Trpds rd Trtecrat rfj x^^P^ XPV~ 

25 GLfjLos SvvapLLs Kal TTpos ro Xa^€.lv. SiOTTep €^ 
oarojv Kal veijpcov Kal oapKos Kal rcjv dXXcov rcbv 
roLovrojv Gvveorr]KaGL rd dpyaviKd rcov fjuopiajv, 
dAA' ovK eKelva eV roijrcjv. 

'Qs likv ovv eveKa nvos Std ravrr]v rrjv alriav 
ex^i' 7T€pl rovrojv rdv elprjfjievov rpoTTov, iirel he. 
^-qrelrai Kal ttojs dvayKalov ex^-iv ovro), ^avepdv on 

80 TTpovTTTJpx^v ovrco TTpos dXXr]Xa exovra i^ dvdyKTjs 

* TO /i€v PZ : om. vulg. 


the Elements ; just so the non-uniform parts come 
later than the uniform. The non-uniform parts, 
indeed, whose manner of composition is that of the 
third sort, have reached the goal and End of the 
whole process ; and we often find that processes of 
formation reach their completion at this point. 

Now animals are composed out of both of these two 
sorts of parts, uniform and non-uniform ; the former, 
however, are for the sake of the latter, as it is to the 
latter that actions and operations belong (e.g. eye, 
nose, the face as a whole, finger, hand, the arm as a 
whole). And inasmuch as the actions and movements 
both of an animal as a whole and of its parts are mani- 
fold, the substances out of which these are composed 
must of necessity possess divers dynameis. Softness is 
is useful for some purposes, hardness for others ; 
some parts must be able to stretch, some to bend. 

In the uniform parts, then, such dynameis are 
found apportioned out separately : one of the parts, 
for instance, will be soft, another hard, while one is 
fluid, another solid ; one viscous, another brittle. 
In the non-uniform parts, on the other hand, these 
dynameis are found in combination, not singly. For 
example, the hand needs one dynamis for the action 
of compressing and another for that of grasping. 
Hence it is that the instrumental parts of the body 
are composed of bones, sinews, flesh, and the rest of 
them, and not the other way round. 

The Cause which I have just stated as controlling 
the relation between them is, of course, a Final 
Cause ; but when we go on to inquire in what sense 
it is necessary that they should be related as they are, 
it becomes clear that they must of necessity have 
been thus related to each other from the beginning. 



646b ^ ^ ^ ^ 

ret [lev yap dvoixoiOfjLeprj eV rcvv ofJLOLOjJLepcov iv- 

hex^Tai ovveordvaiy kol e/c irXeLovajv koL evos, olov 

eVta Tojv oirXdyxycov TroAu/xop^a ydp toZs (^XV' 

jxauLV, i^ ofJiOLOjJLepovs ovra acofiaros cog el-neZv 

aTrAcDs". Tct 8* ofJiOLoiieprj eV tovtojv dSvvaTOV to 

85 ydp 6iJLOLO[JL€peg ttoAA' dv etrj dvofJiOLOjieprj. 
647 a Aid p.kv ovv ravrag ras" alrias rd fxev dirXd /cat 
ofjiOLOfieprj, rd 8e ovvOera /cat dvoixoiofxepr] rcJov 
fJLoplojv ev Tols t>4>ois ioriv. 

*'Ovrojv 8e Twv fiev opyaviKcov fiepdjv rojv S* 
aLGd-qrrjpLOJv iv rols t^Moig, rchv fxev opyavLKcov 
5 eKaoTov dvofioLOficpes icrriv, axjTrep etirov TTporepov, 
Tj 8* aiaOrjcTLg eyyiverai irdcnv iv rols ofMOLOfiepeGLV 
8ta ro rcjv aloOrjGeojv OTTOiavovv ivos rivos etvat 
yevovg, /cat to alaOrjrripLov eKdarov ScKriKov elvai 
rojv alaOrjTcov. rrdcrx^i 8e to SwdfieL oV vtto rod 
evepyeua dvros, coot' eon rd avrd rco yevec, /cat 

10 (et)^ eKelvo ev, /cat rovro ev, /cat 8td rovro X^^P^ 
fJLev t) TTpoGOJTTOv Tj rctJv roLOvrojv ri pLopiojv ouSet? 
eyxetpel Xeyeiv rcov (f^vaioXoyajv ro jiev elvai yrjVf 
rd 8' vSojp, ro 8e TTvp- rcov 8' aludr]rr]pLOJV eKaarov 

1 (eO Ogle. 

" The translation " sense-organ " must not be taken to 
imply that the part through which the sense functions is an 


It is possible for the non-uniform parts to be con- 
structed out of the uniform substances, either out of 
many of them, or out of one only. (Examples of the 
latter are furnished by certain of the viscera, which, 
although they are of manifold shapes and forms, 
yet for all practical purposes may be said to consist 
of one only of the uniform substances.) But it is 
impossible for the uniform substances to be con- 
structed out of the non-uniform parts : for then 
we should have an uniform substance consisting of 
several non-uniform parts, which is absurd. 

These, then, are the Causes o\Wng to which some of 
the parts of animals are simple and uniform ; while 
others are composite and non-uniform. 

Now the parts can also be divided up into (a) 
instrumental parts and (6) sense-organs.'* And we 
may say that each of the instrumental parts of the 
body, as I have stated earlier, is always non-uniform, 
while sensation in all cases takes place in parts that 
are uniform. The reasons why this is so are the 
follo\Wng : The function of each of the senses is 
concerned w-iih a single kind of sensible objects ; and 
the sense-organ in each case must be such as can 
apprehend those objects. Now when one thing 
affects another, the thing which is affected must be 
potentially/ what the other is actually ; so both are the 
same in kind, and therefore if the affecting thing is 
single, the affected one is single too. Hence we 
find that while with regard to the parts of the 
body such as hand, or face, none of the physiologers 
attempts to say that one of them is earth, and 
another water, and another fire ; yet they do conjoin 

" organ " in the stricter meaning of the word. " Organs " 
are normally " non-uniform," sense-organs are " uniform." 



647a ^ ^ 

npos eKaarov iTTL^evyvvovai rcov oroi)(€iu)v , to /X€^■ 

depa (jidoKovres elvai, to 8e rrvp. 

OvGTjs Se rrjs aloB-qoeiOs iv rolg dnXols fxepeaLV 
15 evXoyoJS jJidXiGra aujLtjSatVct ttjv d^r]v iv oiJLOLOjxepei 
fjL€v rJKLcrra 8' aTrXw rcjv aLa9rjTr)pla)v eyyiv€odai' 
fidXiGTa yap avrrj Sok€l TrXeiovcov etvau yevojv, Kal 
TToAAds" ^x^t'^ ivavTLa)G€L? TO VTfo TavTr]v aloOriTov, 
depfxov ipvxpdv, ^r]p6v vypov Kal ei tl dXXo tolovtov 

20 Kal TO TOVTOJV aludiqTrjpLOV, 7] odpi Kal TO TaVTT] 

dvdXoyov, GCxjpLaTajheGTaTOV eVrt rcov alaOrjTrjpiwv. 
inel 8* dSvvaTOV elvai t,a)ov dvev alGdi]GeaJs , Kal 
Sid TOVTO dv etrf dvayKalov €X€iv tols t,(x)ois cvta 
ixopia ofJLOiojxeprj- rj fiev yap aiGdrjGLg iv TOVTOig, 
at Se 7Tpd^€L? Sid tojv dvofjLoiofjiepdjv VTrdp^ovGLV 
25 Tris 8' aLGdrjTiKTJs Swdfiecos Kal Trjg klvovgtjs 

TO t^CpOV Kal TTJS 9p€7TTLKrjg iv TaVTCp fJiOpLCp TOV 

Gco/JiaTog 0VG7]g, Kaddirep iv eVepot? e'lprjTai irpo- 
Tepov, dvayKalov to exov rrpdJTOv piopiov rcts" 
TOLavTas dpxd?, fj [xiv iGTi heKTiKov TrdvTcov tojv 
aLGdrjTcov , Tcijv dTrXdjv etvai jjioptajv, fj Se klvtjtlkov 
30 Kal TTpaKTiKov, TOJV dvopLOLopiepojv . hiorrep iv fikv 
Tols dvaipiois t^ojois to dvdXoyov , iv 8e Tots" ivaipiois 
rj Kaphia tolovtov eoTtv SiaLpetTaL fxev ydp els 
opLOLOfxepri KaOdnep tojv dXXojv GnXdyx^^cov eKaGTOV, 
hid 8e TT^V TOV GX'JP'OLTOS jJiopcfjTjv dvojJLOLOfJiepds 
iGTLV. TaVTTj 8' TjKoXovdrjKe Kal TOJV dXXoJV TOJV 

" See De somno, 455 b 34 ff. 


each of the sense-orgsms with one of the elementary 
substances, and they assert that this sense-organ is 
air, this one fire. 

Sensation thus takes place in the simple parts of 
the body. The organ in which touch takes place is, 
however, as we should expect, the least simple of all 
the sense-organs, though of course like the others it 
is uniform. This is evidently because the sense of 
touch deals with more kinds of sense-objects than 
one : and these objects may have several sorts of 
oppositions in them, e.g. hot and cold, solid and fluid, 
and the like. So the sense-organ which deals with 
these — viz. the flesh, or its counterpart — is the most 
corporeal of all the sense-organs. Another reason 
we might adduce why animals must of necessity 
possess some uniform parts at any rate, is that there 
cannot be such a thing as an animal with no power 
of sensation, and the seat of sensation is the uniform 
parts. (The non-uniform parts supply the means for 
the various activities, not for sensation.) 

Further, since the faculties of sensation and of 
motion and of nutrition are situated in one and the 
same part of the body, as I stated in an earlier work,° 
that part, Mhich is the primary seat of these principles, 
must of necessity be included not only among the 
simple parts but also among the non-uniform parts — 
the former in virtue of receiving all that is perceived 
through the senses, the latter because it has to do 
with motion and action. In blooded animals this 
part is the heart, in bloodless animals the counterpart 
of the heart, for the heart, like every one of the other 
viscera, can be divided up into uniform pieces ; but 
on the other hand it is non-uniform owing to its 
shape and formation. Every one of the other so- 



647 a 

35 KoXovfievcxJV a7T\dy)(y<jjv eVacrrov cac t-^? avrrjs 

647 b yap vXrjs Gweardaiv alfiaTLK-rj yap tj (fivois rravrajv 
avrcov Std to tt^v dioLV e;^€tv irrl TTopoL? (^Xe^LKoXs 
Kal SiaX-ji/jeGiV. KaOoLTrep ovv piovros vSaros IXvs, 
rdXXa GTrXdyxva rrjs Sid rchv (f)Xe^a)v pvoecos rod 
alparos olov Trpox^vp-ard iartv' rj 8e KapSta, 8ta 
5 TO Tojv (fyXe^cov dpx^] ^Ivai Kal ex^tv iv avrfj rrjv 
SvvafjLLV rrjv 8r]fjLLovpyovaav ro af/xa 7rpa)T7]v, €V- 
Xoyov i^ otas dpx^TaL^ rpo^ris e/c roiavrrjg avv- 
eardvai Kal avrrjv. 

AtoTt piev ovv alpLarLKa rrjv pLopcfy-qv rd oirXdyxva 
iarlv ^iprjTaiy Kal Slotl rfj pkv opLOiopeprj rfj 8' 
10 II. Tdjv 8' 6pLOiopL€pcx)V pLopicov iv TOLS ^cpoLS iarl 
rd piev /xaAa/ca Kal vypd, rd Se OKXiqpd Kal areped, 
vypd pL€V t) oAcos" rj eojs dv fj iv rfj (jivaei, olov 
at/xa, Ix^Ry TTipieXrjy oreap, piveXog, yovrj, X^'^^' 
ydXa iv rols exovuL, odp^, Kal rd rovroL? dvdXoyov 
15 ov ydp diravra rd ^cpa rovra>v rcov pLopLOJV re- 
revx^v, dXX evia rwv dvdXoyov rovrcov noiv. rd 
8e ^r]pd Kal oreped rwv opLOLOpuepcov iarlv, otov 
oarovv, aKavOa, vevpov, (j)Xei/j. Kal ydp rojv opLOio- 
pLepdjv Tj SiaipeGLS e^et hia(j)opdv' eon ydp ojs iviojv 
ro piipos opLwvvpiov rw dXco, olov (f)Xe^6s (j)Xeip, ean 

20 8' Cl)S OVX OpLOJVVjXOV, dXXd 7Tpoaa)7TOV 7Tp6(ja)7TOV 


^ otas corr. in loco pluritim litterarum Y : ot as Z {as Z^ in 
rasura). apxerat (vel dpx>] eWi) Peck, cf. 666 a 7, b 1, etc. : 
bexerat vulg. 



called viscera follows suit. They are all composed 
of the same material, as they all have a sanguineous 
character, and this is because they are situated 
upon the channels of the blood-vessels and on the 
points of ramification. All these viscera (excluding 
the heart) may be compared to the mud which 
a running stream deposits ; they are as it were 
deposits left by the current of blood in the blood- 
vessels. As for the heart itself, since it is the starting- 
point of the blood-vessels and contains the substance 
{dynamis) by which the blood is first fashioned, 
it is only to be expected that it will itself be com- 
posed out of that form of nutriment which it 

We have now stated why the viscera are san- 
guineous in formation, and why in one aspect they are 
uniform and in another non-uniform. 

II. Of the uniform parts in animals, some are The uniform 
soft and fluid, some hard and firm. Some are ^^^ ^ 
permanently fluid, some are fluid only so long as they 
are in the living organism — e.g. blood, serum, lard, 
suet, marrow, semen, bile, milk (in the lactiferous 
species), flesh. (As these parts are of course not to 
be found in all animals, add to this list their counter- 
parts.) Other of the uniform parts are solid and 
firm : examples are bone, fish-spine, sinew, blood- 
vessel. This division of the uniform parts admits a 
further distinction : There are some of them of which 
a portion has, in one sense, the same name as the 
whole (e.g. a portion of a blood-vessel has the name 
blood-vessel), and in another sense has not the 
same name. (In no sense is this the case with a 
non-uniform part ; for instance, a portion of a face 
cannot be called face at all.) 

117 • 


647 b 

UpojTov fji€v ovv /cat rots' vypotg fioptocg koI rots 
^rjpols 77-oAAot rpoTTOi rrjs alrias elaiv. ra }i€V yap 
CO? vXt] tlov fJLepojv rcuv dvofiOLopiepajv eartv (eV 
rovTCUv yap avveur'qKev eKaarov rchv opyavLKcov 
fxepcovy i^ OGTOJV Kal vevpojv /cat crap/ccuv /cat dXXojv 

25 roLOvrcov cru/x/SaAAo/xeVoji' rd fxev els rrjv ovalav ra 
8* els TTjv ipyaulav), rd Se rpo(f)rj rovroLS rcov 
vypcjjv iori (Trdvra yap e^ vypov Xa/jL^dvet rr]v 
av^rjcTLv), rd 8e Trepirrcofiara avjJL^ePrjKev etvat 
rovra>v, olov riqv re rrjs i'qpds rpo(f)rjs VTToaraaiv 
/cat rr]v rr^s vypds rots exovai Kvoriv. 

Avrojv he rovrojv at hta^opal TTpds d'AAryAa rod 

30 ^eXriovos eveKev elaiv, olov rwv re aAAojv /cat 
aljjLaros TTpds alfia' rd puev ydp Xenrorepov rd Se 
7Ta)(vrepov /cat rd fxev KaOapcorepov eorru rd de 
OoXepcorepov, en 8e rd [lev ipvxporepov rd Se dep- 
jxdrepov, ev re rots fioploLs rod evos ^cpov {rd ydp 

35 iv roLS dvoj pLepeoi Trpos rd Karoj pLopta diacjiepei 
ravrais rats Sta^opats") /cat erepco rrpos erepov. 

648 a /cat dX(x>s rd piev eVat^Lta rd}v t,cx)cov ecrrl, rd 8' avrt 

rod alpLaros e^^i erepov ri p.6piov roiovrov. 

"EcjTt 8' loxdos p-ev TTOi-qriKcorepov rd rraxvrepov 

at/xa /cat 6epp,6repov, alodrjrLKCjorepov 8e /cat voepd)- 

repov TO Xeirrdrepov Kal ipvxporepov. rrjv avrrjv 8' 

6 e;!^et diacpopdv /cat to ayaAoyov vrrdpxov^ vpos rd 

^ TO . . . virdpxov P : rtDv . . . VTiapxovTOiv vulg. 

*» Or, " reason." 

*• See Introduction, pp. 32 ff. 

' See Introduction, pp. 28 ff. 

** With this passage compare Hippocrates, HipX SiairrjSf 
i. 35. See also below, 650 b 24 ff., and Introduction, pp. 



Now first of all there are many sorts of Cause °' to 
which the existence of these uniform parts, both the 
fluid and the solid ones, is to be ascribed. Some of 
them act as the material for the non-uniform parts 
{e.g. each of the instrumental parts is composed of 
these uniform parts — bones, sinews, fleshes, and the 
like, which contribute either to its essence, or else 
towards the discharge of its proper function). An- 
other group of the uniform parts — fluid ones — act as 
nutriment for the ones just mentioned, since every- 
thing that grows gets the material for its growth 
from what is fluid ; and yet a third group are residues ^ 
produced from the second group : examples, the 
excrement deposited from the solid nutriment and 
(in those animals which have a bladder) from the fluid 

Further, variations are found among different 
specimens of these uniform parts, and this is to sub- 
serve a good purpose. Blood is an excellent illustra- 
tion. Blood can be thin or thick, clear or muddy, 
cold or warm ; and it can be different in different 
parts of the same animal : instances are known of 
animals in M'hich the blood in the upper parts differs 
from that in the lower parts in respect of the char- 
acteristics just enumerated. And of course the 
blood of one animal differs from that of another. 
And there is the general division between the 
animals that have blood and those which instead of it 
have a parf^ which is similar to it though not actually 

The thicker and warmer the blood is, the more it 
makes for strength ; if it tends to be thin and cold, 
it is conducive to sensation and intelligence.'^ The 
same difference holds good with the counterpart of 



648 a ^ 

af/xa* Sto Kal jU-eAirrat Kal d'AAa rotavra ^wa (jipo- 

VLjJLcorepa ttjv (I>vglv iurlv ivaLjJLOJV ttoXXojv, Kal rcov 

evo-ifxajv to, ijjvxpov exovra Kal Aevrrov at/xa (f)povL- 

fJLcorepa rcov ivavrtajv euriv. apiara Se ra Oepfiov 

10 exovra Kal Xenrov Kal KaBapov aju,a yap irpos r 
avhpeiav to. rotavra Kal irpos (j^povqctLV ex^i KaXaj?. 
8l6 Kal ra avoj puopia rrpos ra Kara) ravrrjv e;^et 
TTjV hia(j)Opdv, Kal rrpos ro OrjXv av ro dppev, Kal 
ra Se^ta Trpog ra apiarepa rod acojJLaros. 

^OpLOiws Se Kal rrepl rcov a'AAojv Kal rcov roiovrojv 

15 fjLopiOJV Kal rGiv avo[ioio[iepo}V vrroXiqTrreov ex^iv 
rrjv Siacfiopdv, ra jiev irpos ra epya Kal rrjv ovoiav 
eKOLGrcp rcov l^cocov, ra he irpos ro [^eXriov rj ^etpov, 
otov ixovrcov 6(f)daXfjLov? a/x^orepcov ra ix€v ian 
GKXrjp6(j)daXixa ra S' uypo</>^aA/xa, /cat ra fiev ovk 
ex€i pXe(j)apa ra 3' ^X^''* ^po? ro rr]v oipiv aKpi- 
^eorepav elvai. 

20 "On 8' dvayKalov ex^t^v rj alfia rj ro rovrcp rrjv 
avr7]v €xov (jtvaiv, Kal ris iariv rj rod atfiarog 
(jiVGis, TTpcorov SteAojLteVot? rrepl OepiJLOv Kal ipvxpoVy 
ovrco Kal rrepl rovrov Oecopr^reov rds air las. ttoXXcov 
yap 7) (j)VGis dvdyerai rrpos ravras rds dpxds, Kal 

25 TToXXol SiaiJi(f)LGpr]rovGi TTola depfid Kal rrola ipvxpd 
Tcjv ^cpcjov Tj rcx)v pLopiojv. evioi yap ra evvhpa rcov 
rret^ojv OeppLorepd (jyaoiv elvai, Xeyovres cos erraviGoZ 
rrjv ijjvxporTjra rod ronov rj rrjs (fivoecos avrcbv 

" This sentiment, which at first sight appears to go against 
the Aristotelian teleology, is supported by actual instances, 
e.g. the horns of the backward-grazing oxen (659 a 19) and 
of the deer (663 a 1 1) and the talons of certain birds (694 a 20). 



blood in other creatures : and thus we can explain 
why bees and other similar creatures are of a more 
intelligent nature than many animals that have 
blood in them ; and among the latter class, why- 
some (viz. those whose blood is cold and thin) are 
more intelligent than others. Best of all are those 
animals whose blood is hot and also thin and clear ; 
they stand well both for courage and for intelligence. 
Consequently, too, the upper parts of the body have 
this pre-eminence over the lower parts ; the male over 
the female ; and the right side of the body over the 

WTiat applies to the blood applies as well to the 
other uniform parts and also to the non-uniform 
parts ; similar variations occur. And it must be 
supposed that these variations either have some re- 
ference to the activities of the creatures and to their 
essential nature, or else bring them some advantage 
or disadvantage. ° For example, the eyes of some 
creatures are hard in substance, of others, fluid ; 
some have eyelids, others have not. In both cases 
the difference is for the sake of greater accuracy of 

Before we can go on to consider the reasons why all 
animals must of necessity have blood in them or some- 
thing which possesses the same nature, and also what 
the nature of blood itself is, we must first come to 
some decision about hot and cold. The nature of many 
things is to be referred back to these two principles, 
and there is much dispute about which animals and 
which parts of animals are hot and which are cold. 
Some assert that water-animals are hotter than land- 
animals, and they allege that the creatures' natural 
heat makes up for the coldness of their habitat. 

121 ' 


648 a 

BepjxorrjSy Koi ra dvaifia rcov ivaifxcov /cat to, di^Xea 

Tcbv dppevojVy olov HapjjLeviSr]? ras yvvaiKas rcov 

80 avhpihv depfxorepas elvai (fyrjGL /cat erepoi rives cu? 

Sta TTjv BeppLorriTa /cat TToXvaifio-uoais yLvofidvcov 

rojv yvvaiKelcxJVy ^KfXTTeSoKXrjs 8e rovvavrlov' ert 8* 

at/xa /cat x^^W ^^ H-^^ deppiov oirorepovovv elval 

(f)a<jLV avTOJV, ol Se xpvxpov. el 8' e;!(et roaavrTji' 

TO depjJLov /cat ro ipvxpov dfjL(f)La^rJTr]aLV, ri XPV 

35 TTepc Tcov oiXXcov vTToXa^elv ; ravra yap rjpuv iv- 

apyearara rcov nepl rr]v aicrdrjGLV. 

"Eot/ce he Sta to iroXXaxoJS Xeyeudai to OepjJLO- 

64:8 b re pov ravTa avj-L^aLveiv' eKaoTOs yap hoKeZ rt 

Xeyeiv TavavTia Xeycov. 8t6 8et (jltj XavOdvetv rrojs 

8et TcDv (f)V(jei ovveGTOjrojv tol fiev depfid Xeyeiv to. 

Se ipvxpd, /cat rd [lev irjpd tol 8' vypd, errel oti y 

a'lTia TavTa axehov /cat Oavdrov /cat t,aj7Jg eoiKev 

5 ctvat (f)avep6v, ert 8' vttvov /cat eyprjyopaecos /cat 

aKfjLrjs /cat yqpojs /cat vouov /cat vyieias, dAA' ou 

rpaxvTTjTes koi Xecorr^res ovSe ^apvTrjTeg /cat /cou- 

(f)6T7]Tes odS^ dXXo TOJv ToiovTOJv ovSev COS" eiirelv. 

/cat TOUT* euAoyco? (JVfi^e^rjKev KaOdnep yap iv 

eTepois e'lprjrai TrpoTepov, dpxo-i tcov (f)VOLKajv 

10 GTOixeiojv avTai eloi, OeppLOV Kal i/jvxpov /cat 

^Tjpov /cat vypov. 

YioTepov ovv aTrXajs Xeyerai to dep/xov 7] TrXeo- 
vaxii>s; 8et 817 Xa^eZv Tt epyov tov depfJiOTepov, 7) 

* See above, 646 a 15, and note. 


Further, it is asserted that bloodless animals are 
hotter than those that have blood ; and that females 
are hotter than males, Parmenides and others, for 
instance, assert that women are hotter than men on 
the ground of the menstrual flow, which they say is 
due to their heat and the abundance of their blood. 
Empedocles, however, maintains the opposite 
opinion. Again, some say that blood is hot and bile 
cold, others that bile is hot and blood cold. And if 
there is so much dispute about the hot and the cold, 
which after all are the most distinct of the things 
which affect our senses, what line are we to take 
about the rest of them ? 

Now it looks as if the difficulty is due to the term Tho primary 
" hotter " being used in more senses than one, as there (^) '^'S"^ ' 
seems to be something in what each of these writers and "cold." 
says, though their statements are contradictory. 
Hence we must permit no ambiguity in our application 
of the descriptions " hot " and " cold," " solid " and 
** fluid " to the substances that are found produced by 
nature. It is surely sufficiently established that these 
four principles (and not to any appreciable extent 
roughness, smoothness, heaviness, lightness, or any 
such things) are practically the causes controlhng life 
and death, not to mention sleep and waking, prime ' 
and age, disease and health. And this, after all, is 
but reasonable, because (as I have said pre\'iously in 
another work) these four — hot, cold, solid, fluid — are 
the principles of the physical Elements." 

Let us consider, then, whether the term " hot " 
has one sense or several. To decide this point, we 
must find out what is the particular effect which a 
body has in virtue of being hotter than another, or, 
if there are several such effects, how many there are. 

E 123 


648 b ^ 

TTOcra, el TrXelco. eVa fxev 87) rpoirov Aeyerat ixdXXov 
depfiov v(j)* ov fidXXov OepfxalveraL ro oLTTTOfJLevov, 
15 d'AAaJs- 3e TO fJLaXXov aiGdrjaLV ifiTTOLOVV iv ro) 
diyyaveiv, /cat rovr^ , iav [lerd Xvtttjs. eon 8* ore 
SoKel rovT* elvat ifjevhos' eviore yap rj e^is alria 
rov dXyeZv aloOavoiievois . en ro rrjKruKCjrepov rov 
rr]Krov /cat rod Kavarov KavoruKcorepov . en iav 
fj ro fxev ttXIov ro 8' eXarrov ro avro, ro rrXeov rov 
20 eXdrrovos depjjLorepov. rrpos 8e rourots" Suotv ro 
fJLT] ra)(ea)s ipvxofievov dXXd ^paSeco? depfxorepov, 
/cat ro ddrrov 6eppLaLv6}xevov rod depfxaivofievov 
PpaSecos depfjLorepov elvat, rrjv (f)vaLv ^ajLteV, cus" to 
fjiev evavriov on rroppo), ro 8* opioiov on eyyvs- 
Xeyerai fiev ovv el {jltj irXeovaxcj^? , dXXa TOcraurap^cD? 
25 erepov irepov depfiorepov rovrovs 8e rov? rpoirovs 
dSvvarov inrapxeiv rep avrco iravras' Oeppiaivei fxev 
yap fjidXXov ro l,eov vhcop rrjs (f)Xoy6s, /catet 8e /cat 
r'^Kec ro Kavarov /cat rrjKrov rj cf)X6^, ro 8' vSojp 
ovSev. en depfiorepov jiev ro t,eov vScop 7] TTvp 
oXlyov, iJjvx^raL Se /cat ddrrov /cat /xaAAov to deppLOV 
80 vhojp pLLKpov TTvpos' OV ydp ytverai i/jvxpov TTvp, 
vSojp 8e ylver at irdv. en 0epp.6repov fxev Kara rrjv 
d^Tjv ro t,eov vhojp, xpvx^rai 8e Odrrov /cat m^yvvraL 
rov eXaiov. en ro alp.a Kara p.ev rrfv dcprjv depfio- 
repov uSaros" /cat eXalov, TTrjyvvrai he ddrrov. en 
Xidoi /cat oih-qpos /cat rd roiavra deppLaiverai /xev 
35 ^pahvrepov vharos, /catet he Oepfiavdevra pLoXXov. 
TTpds he rovrois rwv Xeyop.evon> deppLcbv rd jiev 

" Alluding, perhaps, to the expansion due to heat. 


A is said to be " hotter " than B (1) if that which 
comes into contact with it is heated more by it than 
by B. (2) If it produces a more violent sensation 
M'hen touched, and especially if the sensation is 
accompanied by pain. (The latter is not always a 
true indication, since sometimes the pain is due to the 
condition of the percipient.) (3) If it is a better 
melting or burning agent. (4) If it is of the same 
composition as B, but greater in bulk,'^ it is said to be 
"hotter" than B, and in addition (5) if it cools 
more slowly than B, or warms up more quickly : in 
both these cases we call the thing " hotter " in its 
nature — as we call one thing " contrary " to another 
when it is far removed from it, and " like " it when 
it is near it. But although the senses in which 
one thing is said to be " hotter " than another 
are certainly as many as this, if not more, yet 
no one thing can be " hotter " in all of these 
ways at once. For instance, boiling water can im- 
part heat more effectively than flame ; but flame 
is able to cause burning and melting, whereas 
water is not. Again, boiling water is hotter than 
a small fire, but the hot water will cool off more 
quickly and more thoroughly than the small fire, 
since fire does not become cold, but all water 
does. Again, boiling water is hotter to the touch 
than oil, yet it cools and solidifies more quickly. And 
again, blood is warmer to the touch than either water 
or oil, yet it congeals more quickly. Again, stone 
and iron and such substances get hot more slowly 
than water, but once they are hot they burn other 
things more than water can. In addition to all this 
there is another distinction to be made among the 
things that are called " hot " : in some of them the 



649 a aXXoTptav e;^et rr^v depiior-qra ret 8' oiKeiaVy Sta- 
(f)€p€L Se TO deppLov elvai ovtojs tj €K€lvcu? TrXelarov, 
iyyvs yap rod Kara avfi^ej^i^Kos etvai depjjLov dXXa 
fjLrj KaO^ avro ddrepov avrwv wGTTep dv et rt? Xeyoi, 
6 €L ovfi^e^-qKos etr] ro) TTVperrovn elvai fiovGLKco, 
Tov fJLOvaiKov elvai depfxorepov t) rov fxeO^ vyieias 
depp-ov. inel 8* iarl ro fiev KaO^ avro OeppLov ro 
8e Kara ovpL^e^-qKos, i/jvx^raL fiev ^pahvrepov ro 
Kad^ avro, deppuaivei he pidXXov rroXXaKis rrjv ai- 
o67]GLv ro Kara uvpL^e^rjKos' Kal TrdXtv Kaiei {xev 

10 fiaXXov ro Kad^ avro 6epp.6v, olov r] (f)X6^ rov 
v8aro£ rov t,eovros, deppiaivei 8e Kara rrjv d(f)rjv ro 
t,eov ptaXXov, ro Kara avpi^e^iqKos deppiov. cocrre 
(f)avep6v on ro Kplvai hvolv norepov deppLorepov ovx 
aTrXovv coSt pLev yap roSe eorai Oeppiorepov, coSt he 

15 Odrepov. evLa he rcbv roLovrcxJV ovh^ eunv dirXdjs 
elrrelv on BeppLov tj pLT] deppLov o pLev ydp rrore 
rvyxdvei ov ro vTTOKelpLevov ov deppLov, ovvhval^o- 
pievov he deppiov, olov et rt? deZro 6Vo/xa vhan t) 
oihrjpcp Oeppicp' rovrov ydp rov rpoirov ro at/xa 
OeppLov eunv. /cat TTOiel he (f)avep6v iv rols roLov- 

20 rots' on ro ipvxpdv (f)vaLS ris aAA' ov areprjois eonv, 
iv ouoLS ro vTTOKeLjxevov Kara irddos OeppLov eonv. 
rdxo- he Kal rj rod rrvpog (J)vgls, el ervx^, roiavrr) 
ns eariv 'Igojs ydp rd VTroKelpievov eanv rj Kanvos 
Tj dvdpa^, wv rd piev del OeppLov [dvaOvpLLaois ydp d 
KaiTvos), d 8* dvOpa^ drroG^eudels ipvxpd?. eXatov 
he Kal TTevKTj yevoir dv ijjvxpd. ex^i he deppLdrrjra 

" That is, " blood " is really " hot x,"" and the " x " is no 
more hot of its own nature than the " water " in " hot water." 
Cf. 649 b 21 ff., and Torstrik, Rh. Mus. xii. 161 ff. 

* Perhaps a reference to the resin which is in firwood or is 
obtained from it. 


heat is their own ; in others it has been derived from 
\v'ithout. And there is a very great difference be- 
tween these two ways of being hot, because one of 
them comes near to being hot " by accident " and 
not hot " of itself" ; as is obvious, supposing anyone 
were to assert, if a fever-patient were " by accident ** 
a man of culture, that the man of culture is hotter 
than a man whose heat is due to his perfect health. 
Thus some things are hot " of themselves " and 
some hot " by accident," and though the former cool 
more slowly, the latter are in many cases hotter in 
their effect upon the senses. Again, the former have 
a greater power of burning : e.g. a flame burns you 
more than boiling water, yet the boiling water, 
which is hot only " by accident," causes a stronger 
sensation of heat if you touch it. From this it is 
plain that it is no simple matter to decide which of 
two things is the hotter. The first will be hotter in 
one way, and the second in another. In some cases 
of this sort it is actually impossible to say simply that 
a thing is hot or is not hot. I mean cases in which 
the substratum in its permanent nature is not hot, 
but when coupled (with heat) is hot ; as if we were 
to give a special name to hot water or hot iron : that 
is the mode in which blood is hot.** These cases, in 
which the substratum is hot merely through some 
external influence, make it clear that cold is not just a 
privation but a real thing in itself. Perhaps even fire 
may be an instance of this kind. It may be that its 
substratum is smoke or charcoal : and, though smoke 
is always hot because it is an exhalation, charcoal 
when it goes out is cold. In the same way oil 
and firwood ^ become cold. Further, practically all 



649a ^ ^ , f T f \ 

2:> Kol TO, TTvpojdevra Travra o-)(eh6v, olov Kovia /cat 
re^pa, /cat to, vTTOGTrniara rcov ^coojv, /cat tcDv 
TTepiTTOJfJiarojv rj X^^V* '^^ ifJLTreTrvpevcrOai /cat 
iyKaraXeXelcfidal tl eV aurots" Oepfiov. aWov 8e 
rpoTTOv Oepiia} TrevKT] /cat ra TTiova, ro) ra^v /xera- 
jSaAAetv ei? ivipy eiav rrvpos. 

30 Ao/cet Se TO depfiov /cat 7Tr]yv6vai /cat ri^/cctv. ocra 
/Ltey ow L'Saros' piovov, ravra irriyvvoL to ijjvxpoVy 
ocra Se y^^S", to TrOp- /cat Tcoy deppicov Tn^yvvraL vtto 
i/jvxpov raxv pikv oua yrjs pLoiXXov /cat olXvtcos, 
Xvrojs S' oca vSaros. dXXa Trepl pikv tovtojv iv 
iripois StctjptCTTat oacj^iorepov , nroZa ra TrrjKrd, /cat 
TT-^yvvraL 8ta TtVa? alrias. 

35 To Sc Tt OeppLOV /cat ttoIov OeppLorepov eVetSi) 
649 b AeyeTat TT-Aeova;)^;^!)?, ou tov auTov rpoirov VTrdp^ei 
TTO-GLV, dXXd TTpoa^LopiuTeov on KaO^ avro /xev roSe, 
Kara avpipe^rjKos Se vroAAa/ct? ddrepov,^ en 8e 
8vvdpL€L pL€v Tohi, Tohl §6 /caT* ivepyetav, /cat TOvSe 
/xev Tov rpoTTOV rohi, rco pLoiXXov ttjv dcjyrjv Oep- 

5pLaiV€LV, ToSt 8e TO) (j)X6ya TTOieZv /cat nvpovv. 

Xeyopuivov Se tou depp^ov TroXXax^os, dKoXovQ-quei 

hriXov on /cat to i/jvxpov Kara rov avrov Xoyov. 

Kat TTept jLtev Oepp^ov /cat ipvxpov /cat tt}? 


III. 'E;)(op,ep'OV 8e /cat 776pt irjpov /cat vypov SteA- 
10 ^€tv aKoXovOtxJs Tot? elpripiivois . Xeyerai Se ravra 

^ Oipjxa Peck : Oepfiov vulg. 
* TToAAaKi? ^arepov] num raAAo depfioTepov? 

- See 3/^^^or. 382 b 31 fF., 388 b 10 ff. 

'' Probably the text should be altered to read : '* B hotter 
by accident." 

" See note on QiQ a 16, and Introd. p. 32. 


things that have passed through a process of com- 
bustion have heat in them, such as cinder, ash, the 
excrement of animals, and bile (an instance of a 
residue). These have passed through fire and some 
heat is left behind in them. Firwood and fatty 
substances are hot in another way : they can quickly 
change into the actuality of fire. 

We must recognize that " the hot " can cause both 
congealing and melting. Things that consist of 
water only are solidified by the cold, those that con- 
sist of earth, by fire. Again, hot things are solidified 
by cold : those that consist chiefly of earth solidify 
quickly, and the product cannot be dissolved again ; 
those that consist chiefly of water can be dissolved 
after solidification. I have dealt more particularly 
Mith these matters in another work,'' where I have 
stated what things can be solidified, and the causes 
that are responsible for it. 

So, in view of the fact that there are numerous 
senses in which a thing is said to be " hot " or "hotter," 
the same meaning -w-ill not apply to all instances, but 
we must specify further, and say that A is hotter 
" of itself," B perhaps " by accident " ^ ; and again 
that C is hotter potentially, D actually ; and we 
must also say in what way the thing's heat manifests 
itself: e.g. E causes a greater sensation of heat when 
touched ; F causes flame and sets things on fire. 
And of course, if " the hot " is used in all these 
senses, there will be an equal variety of senses 
attaching to " the cold." 

This will suffice for our examination of the terms 
" hot " and " cold," " hotter " and " colder." 

III. It follows on naturallv after this to discuss (?»" solid " 
"the solid" and "the fluid " '^ on similar Unes. ""^"^"''^•' 



649 b 

7TX€ovax<^<s , olov ra /xev Svvdfiei, ra 8' ivepyeta. 

KpvaraXXos yap Kal irav ro TTeTrrjyos vypov Aeyerat 
iyjpa} juev ivepyela Kal Kara ovjijie^riKos, ovra 
Sum/xet Kal Kad^ avra vypd, yrj 8e Kal ri^pa Kal 

15 TO, roiavra fJuxOevra vypuj ivepyela fxev vypd Kal 
Kara avpi^e^-qKos, Kad^ avrd Sc /cat hwdpiei ^rjpd- 
hiaKpidevra he ravra ra jxev vSaros dvaTrXr^GTiKd 
Kal evepyeia Kal hvvdfxei vypd, rd 8e yr^s aTravra 
^rjpd, Kal TO Kvpiojs Kal aTrActJ? ^f]pov rovrov 
/xaAtcrra Aeyerat rdv rpoirov. ojjlolws Se /cat ddrepa 

20 ra vypd Kard rdv avrdv \6yov e-)(ei to Kvpiios Kal 
dnXajs, Kal iirl Oepficov Kal iJjvxp(J^v. tovtojv he 
hiCopLGpievajv <^avepdv ort to atjLta coSt jxev eon 
deppLov [olov TL^ Tjv avTO) TO alpLari etvat;]* Kaddirep 
ydp^ el ovojJiarL tlvl* oriiiaivoipiev rd t^eov vhajp, 
OVTO) Aeyerat • to 8* v7TOKeip,evov /cat o 770Te 6V 

25 alpid ear IV, ov OeppLov Kal Kad* avrd eari fJLev ojs 
6ep[i6v ecrriv, eari 8* cu? ov- ev puev ydp rep 
Xoyo) vrrdp^ei avrov t) OeppLorrjg, cjairep ev rw 
rod XevKov dvOpconov rd XevKov f) he Kard irddos, 
TO at^a ov KaO^ avrd Oepixov.^ 

*0fiOLOJS he Kal rrepl ^r]pov Kal vypov. hid Kal 

^ ^T]pa Peck : ^7/pov vulg. 

^ olov Tt Bekker. haec, signo interrog. adscr., seclusi. 

^ yap Z : om. vulg. 

* ovo/xttTi TLVL PSUZ^ : ovofiaTL Ti EY : ovofiari vulg. 

^ 11. 22-29 interpunctionem correxi. 

" i.e. they assume the shape of the receptacle into which 
they are put. 



These terms are used in several senses. E.g. 
" solid " and " fluid " may mean either potentially 
solid and fluid or actually solid and fluid. Ice 
and other congealed fluids are said to be solid 
actually and by accident, though in themselves and 
potentially they are fluid. On the other hand, earth 
and ash and the like, when they have been mixed 
with a fluid, are fluid actually and by accident, but 
potentially and in themselves they are solid. When 
these mixtures have been resolved again into their 
components, we have on the one hand the watery 
constituents, M'hich are anaplestic,^ and fluid actually 
as well as potentially, and on the other hand the 
earthy components which are all solid : and these 
are the cases where the term " solid " is applicable 
most properly and absolutely. In the same way, 
only those things which are actually as well as poten- 
tially fluid, or hot, or cold, are such in the proper 
and absolute sense of the terms. Bearing this dis- 
tinction in mind, we see it is plain that in one way 
blood is hot [e.g. what is the essential definition of 
blood ?], for the term " blood " is used just as the 
term for " boiling water " would be, if we had a 
special name to denote that ; but in another way, 
i.e. in respect of its permanent substratum, blood is 
not hot. This means that in one respect blood is 
essentially hot, and in another respect is not. Heat 
will be included in the logos of blood, just as fair- 
ness is included in the logos of a fair man, and in 
this way blood is essentially hot ; but in so far as 
it is hot owing to external influence, blood is not 
essentially hot. 

A similar argument would hold with regard to the 
solid and the fluid. And that is why some of these 

e2 131 


649b ^ ^ ^ 

ev rfj cf)V(j€L Twv tolovtojv to, fX€V depjJLa Kal vypd, 
so xwpL^^ojjLeva 8e TTiqyvvrai Kal i/jvxpcL ^atVerat, otov 
TO alfia, ra 8e Oepfia Kal tto-xo? expvra KaOdrrep r) 
XO^tJ, x^ptfo/xei-a S' €K rrjs (f)VG€OJs rojv exovrcDV 
TovvavTiov TTaox^^' 4'^X^'^'^^ 7^9 '^^^ vypaiverai' to 
likv yap alfia ^rjpaiverai /xaAAov, vypaiverai 8' r] 
^avdr) X^^l- '"'^ ^^ fJidXXov Kal rjrrov ju,eTe;)(ety rwv 
35 dvTiK€iixev(x>v 60S" VTTapxov^ Set Tidevai rovrotg. 

650 a Hcos" /xev ouv deppLov Kal ttcos vypov, Kal ttojs 


€LprjTaL crx^Sov. 

'Ettci 8' dvayKT] ndv to av^avopievov Xap-^dveiv 
Tpo(f)'r^v, Tj 8e Tpo(f)rj Trdoiv i^ vypov Kal ^7]pov, Kal 
5 rovTOJV Tj TriijjLs yiverai Kal tj piera^oXr) 8td tt^s" tov 
Oeppiov Svvdfiewg, Kal ra ^a)a rrdvra Kal ra </)UTa, 
Koiv el pLTj 8t' aXXriv alriav, dXXd hid ravrrjv dvay- 
Kolov ex^iv dpx^v deppiov (f)VGiK7Jv. [Kal ravrrjv 
ojGTTep] at {8'y ipyaoiai rrjs rpo(f)rjs TrAetovcov elal 
fioplojv' 7) pikv yap Trpcorrj (f)av€pd rois ^coois 
10 Xeirovpyia hid rod oropiaros ovaa Kal ra)v iv 
rovrcp pLopicov, oacnv tj rpo(f)rj Seirai hiaipioeojs. 
dXX avrrf piev ovSepiids airia 7Tei/jea>£, dAA' €v- 
TTeijjias pidXXov rj ydp els piiKpd hiaipeois rrjs 
rpocj^rjs pdo) TTOiel rep deppicp rrjv ipyaoiav rj 8e rr]s 
dvcD Kal TTJs" Kdro) KoiXias rjhr] pierd deppiorrjros 

^ vndpxov Peck : virdpxovTa vulg. 

' KOI ravT-qv uxnTcp seclusi, <8') supplevi : Kal ravr-qv 
(^vXeloai fJLopiois ivvTrdpxovaav} Camus. 

" See above, note on 644 a 17. 

* See Introduction, p. 34. 

* Lit. " the dynamis of the hot substance," perhaps here 
something more than a mere periphrasis for " the hot sub- 


substances while in the Hving organism are hot and 
fluid, but when separated from it congeal and are 
observed to be cold, as blood does ; others, like 
yellow bile, are hot and of a thick consistency while 
in the organism, but when separated from it undergo 
a change in the opposite direction and become cool 
and fluid. Blood becomes more sohd, yellow bile 
becomes fluid. And we must assume that " more 
and less " ° participation in opposite characteristics 
is a property of these substances. 

We have now pretty well explained in what way 
blood is hot, in what way it is fluid, and in what 
way it participates in opposite characteristics. 

Everything that grows must of necessity take food. 
This food is always supplied by fluid and solid matter, 
and the concoction ^ and transformation of these is 
eifected by the agency of heat.'' Hence, apart from 
other reasons, this would be a sufficient one for 
holding that of necessity all animals and plants 
must have in them a natural source of heat ; though 
there are several parts which exert action upon the 
food. In the case of those animals whose food needs 
to be broken up, the first duty clearly belongs to 
the mouth and the parts in the mouth. But this 
operation does nothing whatever towards causing 
concoction : it merely enables the concoction to 
turn out successfully ; because when the food has 
been broken up into small pieces the action of the 
heat upon it is rendered easier. The natural heat 
comes into play in the upper and in the lower gut, 

stance," as emphasizing its proper and specific natural 
character, which makes it a particularly good agent for 
effecting concoction. See Introduction, pp. 30-32. 



650 a 

15 ^voLKTjS TTOielrai TTjv ireifjiv. woTrep 8e /cat to 

arojJLa rrjs aKarepydarov rpocfyrj? nopos iori, /cat 
TO Gvvex^? aura) fiopiov o KoKovaiv olao^dyov, 
ooa Tcov t,a)OJV e^cL rovro to fiopiov, 'iojs els 
TTjv KoiXiav, ovTio /cat aXXovs hel nopovs^ etvat, St' 
cov arrav XijifjeTai to aojpLa ttjv Tpo^iqv, warrep 

20 e/c cfyaTvrjg, e/c ttjs KoiXtas /cat ttjs tcx)v ivTf.pcov 
(f)V(T€(x>s. TO, fj-ev yap <^VTd Xapi^dvei ttjv Tpo(f)'qv 
KaT€ipyaopi€vr)v €/c Trjg yrjs rat? ptfat? (Sto /cat 
TTepLTTCOfJLa ov ytVerat rots* cjiVTols' ttj yap yfj /cat 
TTJ ev avTTJ depjJLOTTjTL xprjTai ayorrep koiXlo), to, 8e 
t,wa TrdvTa fxev ox^Sov, to, Se nopevTiKa (f)av€poj?y 

25 olov yi]v €V avTols e;^'et to tt^S" kolXlos kvtos, i^ 
-j^S", a)07Tep eKelva Tat? pl^aLS, TauTa Set Ttvt ttjv 
Tpo(j)r]v XapL^dveiv, ecus* to ttjs ixo{JLdvr]s Treipeajs 
Xd^Tj TeXos. Tj fjLev yap tov UTopiaTos ipyacrla rrapa- 
StScoat ttJ KOiXia, rrapd Se TavTiqs €T€pov dvayKalov 
Xapi^dveiv , orrep avpLJ^e^rjKev at yap (jyXe^eg /caTa- 

30 TeivovTai hid tov ixeoevTepiov Trapdnav, KdTCoOev 
dp^dpievai pi^xpi Trjg /cotAtas". Set Se TavTa deojpeZv 
€/c T€ TCOV dvaTopiOJV /cat TTJs (f)vaLKrjs loTopias. 

'ETret Se Trdoris Tpo(f)rjs euTL tl SeKTLKov /cat tcov 
ytvopievwv vreptTTCo/xaTCOv, at Se ^Ae'/8es" otov dyyelov 
alpLaTos elai, <^avep6v oVt to atjLta r] TeXevTaia 

35 Tpo(f)r] TOLS t,oiois Tols eVai/xot? eVTt, TOt? S dvaipLois 

^ aXXovs Set TTopovs Peck : aXXas dpxo.s Set irXelovs vulg. 

" Cf. Shakespeare, Coriolanus i. i. 133-152. 

* The membrane to which the intestines are attached. 

" Dissections (or Anatomy) is a treatise which has not 


which effect the concoction of the food by its aid. 
And, just as the mouth (and in some animals the 
so-called oesophagus too which is continuous with 
it) is the passage for the as yet untreated food, and 
conveys it to the stomach ; so there must be other 
passages through which as from a manger the body 
as a whole may receive its food from the stomach and 
from the system of the intestines." Plants get their 
food from the earth by their roots ; and since it 
is already treated and prepared no residue is pro- 
duced by plants — they use the earth and the heat 
in it instead of a stomach, whereas practically all 
animals, and unmistakably those that move about 
from place to place, have a stomach, or bag, — as it 
were an earth inside them — and in order to get the 
food out of this, so that finally after the successive 
stages of concoction it may reach its completion, they 
must have some instrument corresponding to the 
roots of a plant. The mouth, then, having done its 
duty by the food, passes it on to the stomach, and 
there must of necessity be another part to receive it 
in its turn from the stomach. This duty is under- 
taken by the blood-vessels, which begin at the bottom 
of the mesentery,^ and extend throughout the length 
of it right up to the stomach. These matters should 
be studied in the Dissections ^ and my treatise on 
Natural History.^ 

We see then that there is a receptacle for the food 
at each of its stages, and also for the residues that 
are produced ; and as the blood-vessels are a sort of 
container for the blood, it is plain that the blood (or 
its counterpart) is the final form of that food in Uving 

^ The Natural History, otherwise History of Animals or 
Researches upon Animals. See 495 b 19 IT., 514 b 10 ff. 



650 a 

TO avaXoyov. kol hia rovro fxrj Xaix^dvovcrl t€ 

650 b Tpocfirjv vTToXeLTTCi TOVTO Kal XafJi^dvovGiv av^dverai, 
Kal XPV^'^V^ M^^ ovGtjs vyieivov, (jyavX-qs 8e (f)avXov. 
on fxev ovv to atjLta Tpo(f)rjg ev€K€v vnapxei roXg 
ivaifioLS, (f)av€p6v eK rovrcov Kal tojv tolovtcov. /cat 
yap S(,d TOVTO dtyyavofievov atodrjULV ov Trotet 
5 [ojOTTep ot)S' aXXo tcov TTepLTTajjjLaTOJV ovSev, ovS^ rj 
TpO(f)r)) KaOdvep udp^-^ avTiq yap dtyyavofievr] TroLel 
ata6r](jLV. ov yap ovvex^S eVrt to atjLta TavTrj ovSe 
avjJLTTecjiVKOs, aAA' olov eV dyyeico Tvyxdvei Keijievov 
€V T€ TTJ Kaphia Kal rat? (^XeiJjLV. ov Se Tporrov 
XapL^dvei ef avTOV ra pLopia t7]v av^-qaiv, €tl 8e 
10 TTepl Tp0(f)rj£ oXco?, iv toIs ire pi y€V€aea>£ Kal iv 
irepoLS olKeioTepov eVrt hieXdeiv. vvv 8' cm 
ToorovTOV elprjodix) (togovtov yap xp^^f^H-ov) ^ otl to 
aljxa Tpocf)rjs eVe/ca Kal Tpo(j)r\s tcov fiopLWV eoTiv. 
IV. Tds" Se KaXovpiivas Ivas to fxev ex^i at/xa 

15 TO 8* OVK eX^i, olov TO tG)V €Xd(f)(jOV Kal TTpOKCJV. 

SioTTcp ov TriqyvvTai to tolovtov atfia' tov yap 
OLfxaTO? TO [lev vSaTcoSes fidXXov^ ioTL, 8l6 Kal ov 
TTTiyvvTai, TO 8e yecoSe? TrriyvvTai oruve^aTfil^ovTOs 
TOV vypov' at S' tves" yrjs eluiv. 

2t»jLt/SatVet S* eVta ye Kal yXa(jiVpajTepav ex^LV 

20 ri7V Stavotav tojv tolovtcov, ov Std ttjv ipvxpoTTjTa 

TOV at/xaros", dAAct 8td tt^v XeTTTOTTjTa [xaXXov Kal 

^ 11. 4 f., interpunctionem correxit Cornford. 
^ fidXXov Z : /xdAAov ijjvxpov vulg. 

" In the Second Book. Also in De gen. et corr. 

^ With the sentiments of the following passage and its 
terminology (" more intelligent," " soul," " blend," etc.) 
compare the very interesting passage in Hippocrates, Ilepi 
hiaL-rqs, i. 35. Cf. 648 a 3. 


creatures. This explains why the blood diminishes 
in quantity when no food is taken and increases 
when it is ; and why, when the food is good, the 
blood is healthy, when bad, poor. These and 
similar considerations make it clear that the purpose 
of the blood in living creatures is to provide them 
with nourishment ; and also why it is that when the 
blood is touched it yields no sensation, as flesh does 
when it is touched. Indeed, none of the residues 
yields any sensation either, nor does the nourishment. 
This difference of behaviour is because the blood is 
not continuous with the flesh nor conjoined to it 
organically : it just stands in the heart and in the 
blood-vessels like water in a jar. A description of 
the way in which the parts of the body derive their 
growth from the blood, and the discussion of nourish- 
ment in general, comes more appropriately in the 
treatise on Generation " and elsewhere. For the 
present it is enough to have said that the purpose 
of the blood is to provide nourishment, that is to 
say, nourishment for the parts of the body. So 
much and no more is pertinent to our present 

IV. The blood of some animals contains what are The uniform 
called fibres ; the blood of others (e.g. the deer and B^iood! 
the gazelle) does not. Blood which lacks fibres does 
not congeal, for the following reason. Part of the 
blood is of a more watery nature, and therefore 
does not congeal ; while the other part, which is 
earthy, congeals as the fluid part evaporates off. 
The fibres are this earthy part. 

Now some of the animals whose blood is watery 
have a specially subtle intelligence.^ This is due not 
to the coldness of their blood, but to its greater thin- 


660b ^ ^ 

Sia TO KaSapov etvaf ro yap yeajSes ovSerepov ex^t 

TOVTCDV. €VKivr]TOTepav yap e)(OVGi rr]v atodrjcrLV ra 
XeTTTorepav exovra rrjv vyporrjra /cat KaOapajrepav. 
SiOL yap rovTO Kal tojv avaipLCOv eVia avvercorepav ex^L 

25 rr]v ipvxrjv ivlcov ivaifjLOJv, KaOdnep etprjraL Tvporepov, 
olov 7) /xeAtrra Kal ro yevos to tcov pivppLriKOJV Kav 
et Tt erepov tolovtov ianv. SeiXorepa 8e to. Atav 
vSarcvSr). 6 yap (f)6^os Karaijjvx^i' TTpocohoiToiqTai 
ovv TO) TTadei ra TOLavr7]v exovra rr]v iv rfj Kaphia 

80 Kpaaiv ro yap vSojp ro) ifivxp^ TTrjKrov eGriv. Sto 
Kal raXka ra dvaifxa SeiXorepa rcov evaipiojv iarlv 
d)5 OLTrXiog eiTreXv, Kal aKivqrL^ei re (f)o^o-u[JL€va Kal 
TTpoterai TreptrrcajLtara /cat [xera^aXXei, evia ras 
XpocLS avrcov. ra be ttoXXols exovra Xlav tvas Kal 
TTax^ias yecohearepa rrjv (f)vaiv eorl /cat dvfJLcoSr} ro 

85 rjOos Kal eKorariKa 8td rov dvfiov. depfiorrjros 
yap TTOLTiriKov 6 dvjio?, ra 8e orepea depfiavdevra 
651 a fxdXXov depixaivei rwv vypcov at 8' tides' arepeov Kal 
yewSes, (Lore yivovrai olov rrvpiai ev rco alfxart 
Kal t,eGLV 7TOLOVGLV iv rols OvfiOLS. 8to ol ravpoL Kal 
ol Kairpoi OvfJicoSeis Kal eKorariKoi' ro yap alfxa 
Tovrojv IvajSeorarov, Kal ro ye rod ravpov rdxi'Orra 
6 TTT^yvvrai iravrcov. i^atpovfievajv Be rovrcov rajv 
Ivcjv OX) TTrjyvvr ai ro alfia' Kaddnep yap e/c tttjXov 
€L ns e^eXoL ro yecoSes ov irrjyvvrai ro vSojp, ovro) 
Kal ro at/xa* at yap tve? yT]?- p^^] e^aipovpLevoiV 

• At 648 a 2 ff. 

'' For the connexion between fear and cold cf. 667 a 16, 
692 a 22 ff., and Rhetoric, 1389 b 30. 


ness and clarity, neither of which characteristics 
belongs to the earthy substance ; and an animal 
which has the thinner and clearer sort of fluid in it 
has also a more mobile faculty of sensation. This 
is why, as I said before," some of the bloodless 
creatures have a more intelligent Soul than some 
of the blooded ones ; e.g. the bee and the ants 
and such insects. Those, however, that have ex- 
cessively watery blood are somewhat timorous. 
This is because water is congealed by cold ; and 
coldness also accompanies fear ; therefore in those 
creatures whose heart contains a predominantly 
watery blend, the way is already prepared for 
a timorous disposition.^ This, too, is why, gener- 
ally speaking, the bloodless creatures are more 
timorous than the blooded ones and why they 
stand motionless when they are frightened and 
discharge their residues and (in some cases) change 
their colour. On the other side, there are the 
animals that have specially plentiful and thick 
fibres in their blood ; these are of an earthier 
nature, and are of a passionate temperament and 
liable to outbursts of passion. Passion produces heat ; 
and solids, when they have been heated, give off 
more heat than fluids. So the fibres, which are solid 
and earthy, become as it were embers inside the 
blood and cause it to boil up when the fits of passion 
come on. That is why bulls and boars are so liable 
to these fits of passion. Their blood is very fibrous ; 
indeed, that of the bull is the quickest of all to congeal. 
But just as when the earthy matter is taken out 
of mud, the water which remains does not congeal ; 
so when the fibres, which consist of earth, are taken 
out of the blood, it no longer congeals. If they are 



651 a ^ ^ 

8e TTT^yvvraL, olov vypa yrj vtto xp'u'xpvs' rod yap 
depfJLOv VTTO rod ipvxpov iKdXi^opilvov auveJarjLtt^ct 
10 TO vypov, KaOoLTTep €Lpr]TaL irporepov, /cat TTiqyvvraL 
ovx v'^o Oepfiov dAA' vtto ipvxpov ^rjpaLvojJievov. iv 
Se rots' GcojjLaaLv vypov eVrt 8ta rrjv dcpfiorrjra ttjv 

iv TOZS ^CpOL?, 

IIoAAcov S' iarlv air la rj rod aljxaros <j>vois koi 
Kara to ^dos rolg ^cpoi^ kol Kara rrjv alod-qaiv, 
euAoyoJS" v\y] yap icrn Travrog rod awpLaros' r] yap 

15 Tpo(f>rj vXt], to S* at;Lta -q iaxdrr] rpo(j)ri. ttoXXtjv 
ovv 7T0i€L hia(f)opav depfiov ov /cat ipvxpov /cat Actttov 
/cat TTaxv /cat OoXepov /cat Kadapov. Ix^P ^' ^^''"^ 
to vSarojSe? rod alpiaros Sta to pLrjTTCo 7T€Tr€(f>9ai rj 
SLe(j)ddp9aL, 6oo-t€ o [lev ef dvdyKrjs lx^P> ^ ^' 
aljiaros X^P^^ eVrtV. 

20 V. HifjLeXrj 8e /cat areap SLa(f)€povaL jxev dAA-j^AaJV 
/caret TTjV Tov at/xaro? hia^opdv. eort yap Iko.- 
T€pov avTOJV at/xa ireTrefJiiJLevov 8t' evrpo^iav, /cat ro 
jLt'J7 KaravaXiGKOfxevov els to GapKwSes fxopLov rcov 
^q)ajv, €V7T€7TTOv 8e /cat eurpa^e?. Si^Aot Se ro 

25 AtTrapov aiJTcDv rcov ydp vypojv ro Xirrapov kolvov 
dipos /cat TTvpos ioriv. Std rovro ovhkv e;^€t rail' 
dvaipiojv ovre TnpLeXrjv ovre areap, on ovS^ atfia. 
rdJv 8' ivaijjLCxJV rd [xev GOJfiarcohes exovra ro af/xa 
oriap ex^i [laXXov, ro yap oriap yea)8e? eVrt, 8t6 

" As it were, the " raw " material. 

^ I have used the terms " lard " and " suet " rather than 
" soft fat " and " hard fat " because they represent more 
closely the distinction made by Aristotle. The difference 
between them is now known to be less fundamental, and is 


not taken out, it does congeal, as moist earth does 
under the influence of cold : the cold expels the heat 
and makes the fluid evaporate, as has been said 
before ; so it is due to the solidifying effect of 
the cold, and not of the hot, that what remains 
becomes congealed. And while it is in the body the 
blood is fluid on account of the heat which is there. 

There are many points both in regard to the tem- 
perament of animals and their power of sensation 
which are controlled by the character of the blood. 
This is what we should expect : for the blood is the 
material " of which the whole body consists — material 
in the case of living creatures being nourishment, and 
blood is the final form which the nourishment assumes. 
For this reason a great deal depends upon whether 
the blood be hot, cold, thin, thick, muddy, or clear. 
Serum is the watery part of blood ; and it is watery 
either because it has not yet undergone concoction or 
because it has been already corrupted ; consequently 
some of the serum is the result of a necessary process, 
and some is there for the purpose of producing blood. 

V. The difference between lard and suet ^ is parallel i-ard and 
to a difference in the blood. They both consist of ^^^ 
blood that has been concocted as the result of plentiful . 
nourishment ; that is, the surplus blood that is not 
used up to nourish the fleshy parts of the animal, but 
is well concocted and well nourished. (This point 
is proved by their greasiness, for grease in fluids is 
a combination of Air and Fire.) This explains 
why there is no lard or suet in any of the bloodless 
animals. And among the others, those whose blood 
is denser tend to contain suet rather than lard. Suet 

due to varying proportions of unsaturated triglycerides and 
the lengths of the carbon chains. 



•51 a 

TTrjyvvraL KaOdnep Kal to atfjia to tvcDSe? kol avro 

Kac OL l,cofjLol OL TOLovTOi' oXiyov yap ex^L vSaros, 
30 TO oe TToXv yrjS' Sto to, pLJ] dfjuc/xjohovra dXXa 
Keparwhr) areap ex^i. (j)av€pd 8' rj <f)vois avrcbv 
rod roLovrov gtolx^^ov TrX^prjs ovaa rep Keparcohrjs 
€Lvai Kal darpayaXovs ex^iv diravTa yap ^r]pd kol 
yerjpd rrjv <j)VOLv iarlv. rd 8' djxcpcoSovra /cat 
85 CLKepara /cat TToXvGXiSrj TnfJLeXrjV ex^i dvrl orearog, 
7] ov TnjyvvraL ovSe OpvTTrerai ^iqpaivoiiivr] hid to 
^Tj €Lvai yecoSr] rrjv (fiVGiv avrrjs. 

Merpca puev ovv ravra ovra iv rot? jJLoptois rcov 
651 b t,a)Ci>v co^eAet [Tvpos p^ev yap aiaOrjaiv ovk ejU,7ro8i'^et, 
TTpds 8' vyieiav /cat SvvapLLV ex^i ^oiqBeiav), vnep- 
^dXXovra Se rco TrX'qQeL (jideipei /cat ^Xdnreu. et 
yap TTav yevoiro rd oajp^a mpLeXr^ /cat areap y 0,770- 
Aoit' dv. t,(x)ov jjiev yap iari Kard to al(j0r]TiK6v 
5 p^opiov, Tj 8e odp^ /cat to dvdXoyov aioOriTLKov' rd 
8' at/xa, coo7T€p e'lprjrai /cat rrporepoVy ovk ex^t 
alaOrjGiv, hid ovhe mpLeXj] ovhe areap- atjLta ydp 
TreTTefip^evov eariv. coar^ el irdv yevoiro rd aajpia 
roiovrov, ovk dv exoi ovhepiiav aiadrjaiv. hid kol 
yrjpdaKei raxecjs rd Xiav niova' oAtyat/xa ydp are els 
10 rr)V TTiorrjra dvaXiaKOjJievov rod alp^aros, rd 8' oAty- 
atjLta rihr] tt poojhoTToiiqr ai Trpds rrjv (f)dopdv' rj ydp 
<f)dopd dXiyaipLia ris eari, Kal rd dXiyaipiov^ rradr]- 
riKdv Kal VTTO ipvxpov rod rvxdvros /cat vtto BepyLov. 

^ sic Th. : animal pauci sanguinis S : oXlyov vulg. 


is of an earthy character ; it contains but Httle 
water against a large proportion of earth ; so it 
congeals just as fibrous blood and broths do. So 
too the animals which have horns but have teeth 
in one jaw only contain suet. And it is clear that 
their natural constitution is full of this element 
(earth) from the fact that they have horns and huckle- 
bones, for they are all of them solid and earthy in 
constitution. On the other hand, the animals which 
have incisor teeth in both jaws and have toes (not 
uncloven hoofs), but no horns, contain lard instead 
of suet. Lard neither congeals nor splits up into 
small pieces when it dries, owing to the fact that 
it is not earthy. 

Lard and suet when present in the parts of animals 
in moderate quantities are beneficial : they do not 
hinder the action of the senses, and they contribute 
towards the health and strength of the body. But 
when the amount of them is excessive they are 
destructive and injurious. This is shown by the 
consideration that if the whole body were to become 
lard and suet, it would perish. The sine qua non of a 
living creature is its sensory part, which is flesh or its 
counterpart ; and since, as I have said before, blood 
is not sensitive, neither lard nor suet, which are just 
concocted blood, is sensitive. Therefore, if the whole 
body were to become either of these, it would have 
no sensation whatever. For this reason, too, unduly 
fat animals age quickly : their blood gets used up to 
produce fat, so there is very little of it left ; and 
anything that has but little blood is well on the road 
to decay. In fact, decay is just a form of blood- 
deficiency ; and an animal deficient in blood is 
easily susceptible to the effects of accidental cold and 



651 b ^ 

Koi dyovcxjrepa Srj ra ttlovo. Ion 8ta Tr]v avrrjv 

airiav o yap eSet €K rod at/xaros' et? TrjV yovrjv 

15 levai K0.1 TO GTvepfxa, rovr els rrjv TTipLeXr^v ava- 
XiGKerai koL to areap' Trerrofievov yap to at/xa 
yLverat ravra, ware -r) oXcos ov yiverai 7reptTTC0/xa 
avrois ovhkv rj oXlyov. 

Kat TTepl [lev alp.aros Kal Ixcopos Kal TTLfJLeXrjs 
Kal orearos, rl re iariv eKaarov avrcbv Kal 8td 
TLvas air lag, e'lprjrai. 

20 VI. "EaTt 8e Kal 6 fjLveXog aifiaros res (f>VGL9, Kal 
ovx cQGTrep olovral rives, rrjs yovrjs OTrepfiarLKT] 
SvvafJLLS' SrjXoL 8' iv rots veois TrdpLTTav are yap 
i^ aifxaros (jvvearwrojv rcov pLoplcxJV /cat t-^s" rpo(f)rjs 
ovarjs rols ijJi^pvoLs aljxaros, Kal iv roXs oarols o 

25 fjLveXos alpiarojh'qs eorlv av^avofxevcov 8e Kal ner- 
rofxevcov, KaOdnep Kal ra fiopia fxera^aXXeu Kal ra 
aTrXdyxycL rds XP^*^^ [virep^oXfj yap alpLarwhes Kal 
rd)v OTrXdyxyojv eKaarov euriv en vewv 6vra)v), 
OVTOJ Kal 6 piveXos. 

Kat rojv piev TrtjLteAojScov XcTrapos Kal TnpLeXfj 
opLOLOs, oaois 8e pLT) TnpLeXfj opLOLOv^ dXXd oreap 

80 yiverai ro atpLa irerropievov, rovrois 8e o-TeaTcoST)?. 
8t6 Tot? piev Keparo(f)6poLs Kal pir] dpLcfjcoSovciL 
arearcoSr]s , rols 8' dpucjxjjhovGi Kal iroXvax^^i^^^ 
TTipLeXcoS-qs. (rJKLcrra be roiovros 6 paxlrrjs earl 
pLveXos 8ta TO 8etv avrov elvai avvexrj Kal Ste;^ety 
Sta Trdcrrjs rrjs pdx€Cos hirjp'iqpiev'qs Kara rovs 

85 G(f)OvSvXovs' XiTTapos 8' cov T) orearwSrjs ovk av 
opLolojs TjV Gvvexijs, dXX* rj Opavaros rj vypos.) 
^ ofjLOLOv Z^ : ofMotos alii. 

" e.g. secretion of semen. See above, on 647 b 27. 
" Plato, Timaeus, 73 c. 



heat. The same cause is responsible for the com- 
parative sterility of fat animals : that part of the 
blood which ought to go to form semen and seed gets 
used up in forming lard and suet, which are formed 
by the concoction of blood. Hence in fat animals 
there is either no residue " at all, or else very little. 

I have now spoken of blood, serum, lard and suet, 
describing the nature and the Causes of each of them. 

VI. Marrow, again, is really a form of blood, and not, Jrarrow. 
as some^ think, the same as the seminal substance'' 
of the seed. This is proved by the case of very young 
animals. In the embryo, the parts are composed out 
of blood and its nourishment is blood ; so it is not 
surprising that the marrow in the bones has a blood- 
like appearance. As they grow and become mature,^ 
the marrow changes its colour just like the other parts ^ 
of the body and the viscera, which while the creature 
is young all have a blood-like appearance owing to the 
large quantity of blood in them. 

Animals which contain lard have greasy marrow, 
like lard ; those whose concocted blood produces not 
a substance like lard but suet have suety marrow. 
Hence, in the horned animals which have teeth in 
one jaw only the marrow is suety, and in the animals 
that have teeth in both jaws and are polydactylous it 
is like lard. (The spinal marrow cannot possibly be 
of this nature because it has to be continuous and 
to pass without a break right through the whole 
spine which is divided into separate vertebrae ; and if 
it were fatty or suety it could not hold together as 
well as it does, but it would be either brittle or fluid.) 

" Dynamis. See Introduction, pp. 30 if. and note on 646 a 14. 

^ Lit. " are concocted." 

• A good instance of Aristotle's usage of the term " part." 



"KvLa 8' ovK e;)(et raJv ^cLcov cos a^icos €L7T€lv 
jxveXov, OGOJV TO, Surd laxvpa Kal ttvkvol, olov ra 
652 a Tou XeovTOS' rovTov yap ra oord, Sua to TrdfXTTav 
darjfjLov e'x^tv, So/cet ovk €X€lv oAco? fJLveXov. eirel 
8e T19V jLtev TcDv ocrrcov avdyKf] (f)V(nv vnapx^iv toZs 
t,cpOLs r] TO dvaAoyov Tot? do-TOtS", ofov TOtS" ivvSpois 
6 rrjv aKavdav, dvayKolov eviois v-napx^^v Kal fiveXov, 
ilirrepiXa}Ji^avop.iviqs rrjg rpo(f)rjs e^ ':7s' yiverai ra 
Sard, on 8' rj Tpo(f>rj Tjdoiv alfxa, €ip7]TaL irpo- 
repov. €vX6yoJs 8e /cat orearajheis ol {iveXol Kal 
7n/xeAa)8ets" elcrlv Std yap rrjv dXeav ttjv yLVOfJbevrjv 
vrro rod Trepiex^crdaL roXs ogtols TTeTreraL to at/xa, 
10 75 8e Kad" avro Triipis alpiaTOS oreap Kal TTLpLeXi] 
iaTLv. Kal iv toIs ^r] ra Sard ttukvo, kxovcn Kai 
laxvpoL €vX6yoJS iv roig fxev ovk eveon, rots 8' 
oXlyos^ eveoTLV els yap ra Sard dvaXia Ker ai rj 


*Ev 8e Tot? fxr] exovGiv Sard dAA' aKavdav 6 

pax^T7]s fxovos iarl [xveXos' dAtyat/xd re yap </>ucret 

15 vTTapx^L ovra, Kal kolXt] aKavOa piovov rj rijs pa- 

^ecos" lor IV. hio iv ravrrj iyyiverai' p.ovrj re yap 

e;^et ;^ct>pav, Kal pLovTj Selrai avvSeufJiov Sid rds 

SiaX7ji/j€Ls. 8td Kal 6 ivravda pLveXog, (Zanep 

elprjr ai, dXXoiorepos ioriv hid rd dvrl rrepovrjs 

1 oXiyois per errorem Bekker. 


Some animals have no marrow worth mentioning l 
these are they whose bones are strong and close- 
textured : for instance, the Lion, whose bones con- 
tain so insignificant an amount of marrow that they 
look as if they contained none at all. Now in view of 
the fact that the bodies of animals must have in them 
either bones or the counterpart of bones {e.g. the 
spines in water-animals), it follows of necessity that 
some of them must contain marrow as well, due to the 
enclosing of the nourishment out of which the bones 
are formed. Now we have stated already that the 
nourishment of all the parts of the body is blood. 
And it is quite reasonable that the various sorts of 
marrow should be suety and lardy ; because the 
blood undergoes concoction owing to the heat pro- 
duced by its being surrounded by bone, and the 
product of blood when it undergoes concoction by 
itself is suet and lard. And also, of the animals that 
have strong, close-textured bones, some have no 
marrow, others have but little, and this is reasonable 
too, because the nourishment gets used up to supply 
the substance of the bones themselves. 

In those animals that have no bones but spine 
instead, the backbone contains the only marrow they 
possess. It is the nature of these creatures to have 
but a small amount of blood, and their only hollow 
spine is that of the backbone. Therefore the marrow 
is formed in it — indeed, it is the only bone where 
there is room for the marrow, and the only one 
which requires something to connect it together, 
owing to its being divided up into segments. 
This also explains why the marrow here is (as 
I have already said) somewhat different from the 
marrow elsewhere. It has to serve as a fastening, 



652 a 

yap yiveadai yXiaxpo?, koL vevpajh-qs iarlv tv' 

20 Ata Tt fxev ovv ixveXov e;^6t to, Joia ra e^ovra 
fjLveXov, etprjTav Koi ri ianv 6 jjLveXos, eV tovtojv 
<j)av€p6v, OTL rrj5 alfjLarLKrj? Tpo(j)rjs rrjs et? ogto, 
Kal aKavOav ixepiH^opievrjs iarl to e/x7reptAa^j8avo- 
fxevov TTepLTTOjfia Tr€(j)dev. 

VII. Ylepl S* iyK€(f)dXov gx^^ov icrnv ixofJLevov 

25 elneXv ttoXXoXs yap Kal 6 eyKec^aXos So/cet fiveXos 
etvai Kal apx^} tov [xveXov 8ta ro ovvex'^ tov 
paxcTTjv avTO) opdv fJiveXov. eori he irdv rovvavrlov 
avro) T7JV (f)VGLV (1)£ elrreZv 6 {lev yap lyKecjyaXos 
ijjvxpoTarov rcov iv rco aaypLari fioptajv, 6 Se piveXog 
deppLos TTjv (/iVGLV StjXol 8' Tj XiTTapoTrjg avrov Kal 

30 TO ttIov. 8 to Kal Gvvex^s 6 paxiTT}? ray iyK€(f)dXa) 
€GTLV' del yap rj (jiVGLS [xr^xci^'drat irpos ttjv eKdorov 
VTTep^oXrjv PorjOeLav rrjv rod ivavriov TrapeSplav, tva 
dvLGdl^T] TT^v darepov vTrep^oXrjv Odrepov. on fiev 
ovv 6 p.veX6s Oeppios^ Igtl, hrjXov ck ttoXXcov. tj 8e 

35 tov iyK€(f)dXov ijjvxpoTiqs (jiavepd fxev Kal /cara t'))^ 
dl^LV, €TL 8' dvaipLOTaTov T(2)v vypcov Tojv iv T(h 
GWfiaTL TrdvTOJv {ovS^ oTLOvv yap atfiaTOs ex^i €V 
652 b avTcp) Kal avxp^'TjpoTaTOV. cgtl 8* ovt€ TrepiTTOjpLa 
ovTe Tiov Gvvex^v popiajv, dXXd Ihios r) (f)VGL9, Kal 
evXoyoJS ToiavTrj. otl p.ev ovv ovk ex^i Gvvex^i-OLV 
ovSefxlav irpos rd acGdrjTLKa pLopia, SrjXov fiev Kal 

5 8ta TrJ9 oipeo)?, ert 8e /jlclXXov toj pi]Sepiav TTOielv 
aLG9r]GLV 6iyyav6p.evoSy wGirep ovhe to atpia ovSe to 
TTepLTTa>p.a tojv ^cocov. 

* Oepnos PZ : depiJLOv vulg. 


and so it is sticky ; and it is sinewy too so that it 
can stretch. 

We have now explained why marrow is present in 
certain animals. We have also made clear what 
marrow is. The surplus of the blood-like nourishment 
which is distributed to the bones and spine gets 
enclosed within them, and after it has undergone 
concoction then it is marrow. 

yil. The brain is the next subject on our list. It Brain, 
comes appropriately after the marrow, as many think 
that the brain is really marrow " and is the source of 
the marrow, because, as observation shows, the spinal 
marrow is continuous with the brain. As a matter 
of fact, however, the two are quite opposite in nature. 
The brain is the coldest of all the parts in the body, 
whereas the marrow is hot, as is shown by the fact 
that it is greasy and fat. And that is the real reason 
why the spinal marrow is continuous with the brain. 
Nature is always contriving to set next to anything 
that is excessive a reinforcement of the opposite sub- 
stance, so that the one may level out the excess of 
the other. Now there are many indications that the 
marrow is hot ; and the coldness of the brain is 
shown not only by its being cold to the touch, but 
also by its being the driest of all the fluid parts of the 
body and the one that has the least blood in it — in 
fact, it has none at all. It is, however, not a residue, 
nor is it to be classed among the parts that are con- 
tinuous. It is peculiar in its nature, and this after all 
is but reasonable. Inspection shows that the brain 
has no continuity with the sensory parts, but this is 
shown still more unmistakably by the fact that like 
the blood and the residue of animals it produces no 
sensation when it is touched. 

« Cf. Plato, Timaeus 75 c, d. 



652b ^ ^ 

*Y77ap;^et Se roZs ^</>ot? rrpo'S rrjv ttjs (f)VG€OJs 
oXrjg GOJTrjpLav. ol fxev yap rod ^cpov rrjv ifjvx'^v 
rideaai TTup tj TOiavrrjv tlvol SvvajjLLv, ^oprtKajs 
Tidevres' ^eXriov 8' 'Igojs (j)dvai iv tolovtco tlvl 

10 crco/xart avveordvai. rovrov S' atrtov on rolg rrjs 
ipv)(fj£ epyoLS VTrr^peTLKcorarov tojv uiopLdrcov ro 
depfxov ianv ro rpecjieiv yap Kal klv€lv ^v)(7Jg 
epyov iori, ravra Se Sta ravrrj^ /xaAtara yiverai 
rrjs Svvdfieojs. ojiolov ovv ro rrjv ipvxr]v elvat 
(f)dvaL TTvp Kal ro Tipiova r) rpvTravov rov reKrova 

15 ^ '7"']^' reKroviKrjVy on ro epyov rrepaiverai iyyvs 
dXX-qXcxJV ovoiv. on fiev ovv OeppLoriqros rd Joja 
fierex^LV dvayKalov, hrjXov e/<r rovrojv eVet S' 
diravra Setrat ttj? ivavrlas porrrj?, Iva rvyxdvr} rov 
fierpiov Kal rod piiaov (rr]v yap ovoriav €;^et rovro 
Kal rov XoyoVy rojv 8' aKpojv eKdrepov ovk e;!^et 

20 x^P^^)} ^^d ravrrjv rr]v air lav rrpo? rov rrjg KapSlas 
roTTOV Kal r7]v iv avrfj OeppLonqra pie fjLTjxdvqr ai rov 
iyK€(f)aXov rj (J)vgls, Kal rovrov X^P^^ VTrdpx^t rovro 
ro [jLopLov rolg ^ojols, rrjv <^vgiv exov kolvtjv vSaros 
Kal yrJ9y Kal Std rovro rd {/xev)^ evaijda ex^i- rrdvra 
iyKe<paXov, rwv 8' dXXojv ovSev tus" etVetv, ttXtjv ore 

25 /caret TO dvdXoyoVy otov 6 ttoXvttovs' oXiyoOeppia ydp 
Trdvra hud rr^v dvaipilav. 

'0 pikv ovv eyKe<f>aXos evKparov rroieZ rrjv iv rrj 
Kaphla OeppLorrjra Kal ^€Glv Iva he Kal rovro ro 
fjLopLov rvyxdvr) pLerplas Oepfiorrjrog, a^* eKaripas 
rrjg ^Ae^os", rrjs re fxeydXr^s Kal rrjs KaXovpLevrjs 

80 doprrjg, reXevrcoGiv at ^Ae^e? elg rr]v pnqviyya rrjv 

^ </xev> Rackham. 

" e.ff. Democritus ; see Aristotle, De anima, 403 b 31. 
' Or, " proportion." 



The brain is present in order to preserve the animal 
organism as a whole. Some " maintain that the Soul 
of an animal is Fire or some such substance. This is 
a crude way of putting it ; and might be improved 
upon by saying that the Soul subsists in some body 
of a fiery nature. The reason for this is that the 
hot substance is the most serviceable of all for the 
activities of the Soul, since one of the activities of 
the Soul is to nourish ; another is to cause motion ; 
and these are most readily effected by means of 
this substance (\iz. the hot). So to say that the 
Soul is fire is like saying that the craftsman, or his 
craft, is the saw or the auger which he uses, on 
the ground that the activity is performed while the 
two are near together. From what we have said this 
at any rate is clear : animals must of necessity have in 
them a certain amount of heat. Now, everything needs 
something to counterbalance it, so that it may achieve 
moderation and the mean ; for it is the mean, and 
not either of the extremes apart, which has re- 
ality and rationality.^ For this cause nature has 
contrived the brain to counterbalance the region of 
the heart and the heat in it ; and that is Avhy animals 
have a brain, the composition of which is a combina- 
tion of Water and Earth. Hence, although all 
blooded animals have a brain, practically none of 
the others has (unless it be just a counterpart, as 
in the case of the Octopus), for since they lack blood 
they have but little heat. 

The brain, then, makes the heat and the boiling in 
the heart well blent and tempered ; yet in order that 
the brain may still have a moderate heat, blood- 
vessels run from the great Blood-vessel and what is 
known as the Aorta, till they reach the membrane 



662 b 

Tvepl rov iyK€(f>aXov. npos Se to rfj 9ep[x6Tr]TL firj 

jSAaTrretv, dvrl fxev jxeydXcov (^Kacy oXiyojv nvKval 
Kal Aerrrat (/)Ae/3es" 7r€pL€)(ov(jLv avrov, dvrl he BoXe- 
pov^ Kal Ttax^os at^aro? Actttov /cat Kadapov. 8to 
Koi rd pevpiara rols GcopiaaLV e/c rrjs K€(f)aXrjs eari 

35 TT^v dpx^jv, doois dv fj rd irepl rov iyKe(f)aXov 
ipvxpdrepa rrjs crvp^p^erpov Kpdoeojs' dvadvpLioj- 
653 a pLevTjs ydp hid rdJv ^Xe^cov dvco rrjs Tpo(j)'r]S to 
TTepiTTCo/xa i/jvxop'^vov hid rrjv rov tottov tovtov 
hvvapLiv pevp^ara Troiei ^Aey/xaros" Kal Ix^jpog. 
hei he XafieZv, (hs pieydXco irapeiKat^ovra puKpoVy 
ofxoLcos Gvpi^alveiv axjirep rrjv rwv vercov yeveaiv 
5 dvaOvpiicjp.ev'qs ydp eK rrjs yrjs rrjs drpiihos Kal 
(fyepopLevqs vtto rod deppiov irpos rov dvco roirov, 
drav ev rco v-rrep rijg yrjs yeviqrai depi dvri ijjvxp<^, 
Gvviorarai rrdXiv els vhojp hid rrjv ipv^iv Kal pel 
Kara) Tvpos Tr)v yrjv. dXXd rrepl jjiev rovrcov ev rais 
rwv vogcjov dpxoiis dppiorrei Xeyeiv, ecf)^ ogov rijs <f>v- 

10 GiKT]s ^iXoGO(j)ias iorlv elireZv irepl avrojv. 

riotet he Kal rov vttvov rols ^cpois rovro rd 
fjLopiov rols exovGiv eyKe^aXov, rols he p.r] e^oucrt 
TO dvdXoyov Karaipvxov ydp rrjv diro rrjs rpo^rjs 
rod aifiaros errippvoiv (j] Kal hid rivas opioias 
alrias dXXas), ^apvvei re rov roirov {hio rrjv KecjiaXrjv 

15 Kaprjl3apovGiv oi vrrvcoGGovres) Kal Karco noiei ro 
deppiov V7TO(j>evyeiv pierd rov a'ipiaros. hio rrXeZov 
d6poil,6pievov errl rov Kdrco rorrov drrepydt^erai rov 
VTTVOV, Kal ro hvvaodai eGrdvai 6p6d d(f)aipeiraL 
OGa ru)v t,cx)Lov 6p9d rrjv (f)VGiv eGri, rcov S* d'AAcoi' 

*■ (Kal) Rackham. 
2 OoXepov colli. Buss, (turbidi 2) : ttoAAou vulg. 



which surrounds the brain. And in order to prevent 
injury being done through heat, the blood-vessels 
surrounding it are not few and large but small and 
multitudinous ; and the blood is not muddy and 
thick but thin and clear. This also explains why 
fluxes begin in the head ; they occur when the 
parts around the brain are colder than the rightly- 
proportioned blend." What happens is that, as the 
nourishment exhales upwards through the blood- 
vessels, the residue from it becomes cooled owing 
to the specific nature of the brain, and produces 
fluxes of phlegm and serum. And we should be justi- 
fied in maintaining that this process resembles, on 
a small scale, the one which produces rain-showers. 
Damp vapour exhales up from the earth and is carried 
into the upper regions by the heat ; and when it 
reaches the cold air up aloft, it condenses back again 
into water owing to the cold, and pours down to- 
wards the earth. However, so far as Natural Philo- 
sophy is concerned with these matters, the proper 
place to speak of them is in the Origins of Diseases.^ 
Furthermore, it is the brain (or, if there is no brain, 
its counterpart) which produces sleep in animals. 
It cools the onflow of blood which comes from the 
food (or else is due to other causes of the same sort), 
and weighs down the part where it is (that is why 
when a person is sleepy his head is weighed do>\Ti), 
and causes the hot substance to escape below to- 
gether with the blood. Hence, the blood accumu- 
lates unduly in the lower region of the body and 
produces sleep ; at the same time it takes away 
from those animals whose nature is to stand upright 
the power to do so, and the others it prevents from 

* See p. 38. " No such treatise exists. 



653a ^ ^ ^ N X r ./ t 

20 aura eV re rots' Trept alaB-qoeoJS koL Trepl vttvov 

"Otl S' IgtIv 6 iyK€(f>aXog kolvos vSarog Kal 
yTjs", Si-jXoL TO GvpL^alvov 7T€pl avTov €ifj6pL€vo? yap 
yiverai irjpos Kal OKXvipos, Kal AetVerat ro yewhes 
i^arpLLaOevTOS rod vSaros vtto rrjs deppLonqros, 
a>u7T€p TO, TcDv -^(^ehpoTrojv lifj-qpLara Kal tojv aAAcov 

26 KapTTOJV, Sea TO yrjs elvai to TrXeZorov piepog, i^- 
LOVTog rod pii)(6evros vypov' Kal yap ravra yiverai 
OKXrjpa Kal yerjpa TTapLvav. 

*'E;)(et Se rajv ^cocov iyKecfiaXov TrXelarov avOpcorros 
(1)5 Kara piiyeBos, Kal raJv dvOpwTTOJV ol appeves rwv 
drjXeicnv' Kal yap rov rrepl rrjv Kaphiav Kal rov 

80 TrXevpLova roTTOV Oepporarov Kal ivacpLorarov. Sio 
Kal pLovov iorl rwv t^axMV 6p66v rj yap rod OeppLOV 
<f)VGis ivLGXvovGa TroL€L rrjv av^rjGLv 0.770 rod piCGOv 
Kara rrjv avrrjg (f)opdv. rrpos ovv 7ToXXr]v deppiorrjra 
avriKeirai TrXeiwv vyporrjg Kal i/jvxporrjg, Kal Sid ro 
TrXrjdog oxjjiairara m^yvvraL ro rrepl rrjv K€(f)aXrjv 

86 oGrovv, o KaXovGL ^peypta rives, Sto, ro ttoXvv 
Xpovov ro deppLov aTrarpLit^eLV rcov 8' aAAcov ovSevl 
rovro Gvp^acvec rwv evaipicov ^cowv. Kal pa<f)dg 8e 
653 b rrXeiGras exec rrepl rrjv Ke(f)aX-qv, Kal ro dppev 
TrXeiovs rdjv drjXeiiov, hid rrjv avrrjv alriav, ottojs 6 
rorros evrrvovs fj, Kal pidXXov 6 irXeicov eyKe(f)aXos' 
vypatvopLevos ydp rj ^rjpaLvopLevog pdXXov ov TTOL-qGeu 
ro avrov epyov, aAA' rj ov ipv^et rj Tn]^eL, wGre 

« See J)e somno, 455 b 28 ff., especially 456 b 17 ff. 
*• The cranial bone, which covers the anterior fontanelle. 


holding their heads upright. These matters have 
been spoken of separately in the treatises on Sensation 
and on Sleeps 

I said the brain is compounded of Water and 
Earth. This is sho\Mi by what happens when it is 
boiled. Then it becomes solid and hard : the earthy 
substance is left behind after the Water has evapor- 
ated owing to the heat. It is just what happens 
when pulse and other forms of fruit are boiled ; they 
also get hard and earthy altogether, because the 
greater part of them is earth, and the fluid mixed 
with it departs when they are boiled. 

Of all the animals, man has the largest brain for 
his size ; and men have a larger brain than women. 
In both cases the largeness is due to there being a 
great deal of heat and blood in the region around the 
heart and the lung. This too explains why man is 
the only animal that stands upright. As the hot sub- 
stance prevails in the body it induces growth, begin- 
ning from the centre along its o\\'n line of travel. 
It is against great heat, then, that a large supply of 
fluid and cold is provided. This bulk of moisture 
is also the reason why the bone that surrounds the 
brain (called by some the bregma) ^ is the last of all 
to solidify ; the hot substance takes a long time to 
evaporate it off. This phenomenon does not occur 
in any other of the blooded animals. Again, man 
has more sutures in the skull than any other animal, 
and males have more than females. The size of the 
brain is the reason for this also ; it is to secure 
ventilation, and the larger the brain, the more 
ventilation it requires. If the brain becomes unduly 
fluid or unduly solid, it will not perform its proper 
function; but will either fail to cool the blood or else 

F 155. 


653b ^ ^ 

6 voGovs Kal TTapavoias TTOLeiv /cat davdrovs' to yap 

€V rfj KapSla Beppiov Kal rj dpx'^ avpLTraBeGrarov 

ean Kal ra^^elav TToielrai rr^v aiGdrjaLV ju-era/SaA- 

XovTos TL Kal TTaaxovTOs rod irepl rov iyKi<j)aXov 


YVepl fi€V ovv Tcov aviK^vTOJV Tols ^cooLg vypojv 

10 ax^^ov elpiqrai rrepl Travrcov rcbv 8* vor^poyevcbv 
ra T€ Tre/JiTTcu/xaTa rrj? Tpo(f)rjs iarl, to tc rrjs 
Kvarecos UTroCTri^/xa Kal to t-^s" /cotAta?, Kal Trapa 
raura yovrj Kal ydXa rols tt€(J)Vk6uiv ^x^iv eKaora 
rovTCov. rd fiev ovv rrjg rpoc/irjs TTepirrajpiara nepl 
rrjv rijs Tpo(f)rj? OKeipiv Kal decnpiav oiKelovs ^x^^ 

15 rovs Xoyovs, tlol re rcjv t^cpcjv vTrdpx^i' Kal Sid 
rivas alrias, rd Se TT€pl UTTepfiaros Kal ydXaKros iv 
roTs TTepl yevioeojs' to puev ydp dpx^ yevioecjs 
avTOJV €GTL, TO Se x^P^^ yevcaeojs. 

VIII. Ilepl 8e Tcov dXXojv jdopicov raJv 6fJLOi,o~ 

20 fJLepwv OKerrriov, Kal Trpwrov nepl oapKos iv rolg 
^xovai GapKas, iv 8e rols a'AAoi? to dvdXoyov rovro 
ydp dpx^i Kal ato^a KaO'' avro rcov l,cpa)v iariv. 
SrjXov 8e Kal /caret, rov Xoyov rd ydp ^coov opi- 
l^ofjLeOa rep €;\;€tv aiodrjaiv, npcarov Be rrjV Trpcjorrjv 
avrrj 8' iorlv d(j)'q, ravrrjs 8* alodrinqpiov rd roiov- 

25 rov fxoptov ioTLV, -rjroL ro npcorov, ioairep 7] Koprj 

" At De gen. an. 722 a, 776 a 15 fP. 


PARTS OF ANIMALS, II. vii.-viii. 

will make it set fast, thus producing various forms of 
disease, madness, and death. Indeed, the heat that 
is in the heart, being the source, is extremely re- 
sponsive to any influence upon it ; and if the blood 
which surrounds the brain undergoes any change or 
any other affection, then this heat at once becomes 
sensitive of it. 

We may now claim to have considered all the fluids 
which are present in animal bodies from their very 
earliest stages. There are others which are first 
produced only at some latter stage, and among these 
we must reckon the residues of the nourishment — 
that is to say, the deposits from the bladder and 
from the gut ; and also semen, and milk ; these 
make their appearance according to the species and 
sex of the animal concerned. Discussion of the resi- 
dues of the nourishment will come in appropriately 
during our general consideration and examination 
of nourishment ; we shall then show in what animals 
they occur, and why they do so. Semen, which 
gives rise to generation, and milk, which exists on 
account of generation, we shall deal with in the 
treatise on Generation.'^ 

VIII. We must now go on to consider the rest of Flesh and 
the uniform parts. Let us take first of all Flesh (and, ^^^^^* 
where Flesh is absent, its counterpart), for this is to 
animals both a principle and a body in itself. Its 
primacy can also be logically shown, as follows. We 
define an animal as something that has the powder of 
sensation, and chiefly the primary sensation, which 
is touch ; and the organ through which this sensation 
is effected is the flesh (or its counterpart). And 
flesh is either its primary organ (comparable to the 
pupil in the case of sight), or else it is the organ and 



653b ^ ^ 

TTJs oipecos, 7) TO 8t' ov GVveLX-qiiixivov , cjanep dv et 
rt? TTpoaXd^OL rjj Kopj] ro 8ta(/>aves' rrdv. eirl fiev 
ovv rdjv dXXwv aLuOi]<j€Cx}v dh-vvarov re koI ovhev 
rrpovpyov rovr tjv TTOirjaaL rfj cf)vaeL, to 8' aTTTLKou 
i^ dvayKfj^' jjlovov yap 7) pLaXiGTa rovr iarl croj^a- 
80 TcuSes" rcvv aludririqpiojv. Kara he rrjv a'iodr]GLV 
<f)avep6v Tvdvra rdXXa rovrov X^P^^ ovra, Xeyoj 8* 
otov dord /cat Sepfia /cat vevpa /cat cf)Xe^es, ert 8e 
rpLX^s Kal ro rojv 6vvx<J^v yevog, /cat et rt roiovrov 
erepov eoriv. rj fiev yap rojv dardJv ^vuis Gcort]- 
pias eveKev fie inqxdvrjr at (rovy^ [laXaKov, OKXrjpd 
85 r7]v (j)VGiv ovoa, ev rol? exovacv Sard' ev 8e rot? 
piT] exovcTi, ro dvdXoyov, olov ev rots' IxO^Grt- toZs 
fjLev aKavda roXg 8e x^^^P^^- 

To, fiev ovv ex^t row ^cocov evros rrjv rotavrrjv 

654 a ^oiqOeiaVy eVta he rojv dvaipiojv e/cros", wanep rdJv n 
p.aXaKO(jr paKOiv e/caarov, otov /cap/ctVot /cat rd rdJv 
Kapd^ojv yevog, /cat to rojv oarpaKoheppcov (Jjg- 
avrcog, otov rd KaXovfieva oar pea' Trdai yap rovrotg 
TO pev oapKcoheg evros, rd he Gvvexov /cat (f)vXdrrov 
6 e/CTO? TO yedjheg eoriv Trpos ydp rfj (jyvXaKfj rrjs 
ovvex^^oLS, TO) ex^i-v dXiyov avrdjv rrjv <f)VOLV deppiov 
dvalpcov dvrojVy olov TTViyeds ris rrepiKeipievov rd 
dorpaKov (j}vXdrrei rd epLTreTTvpevpievov Oeppidv. rj 
he x^^djvrj /cat rd rojv epbdhajv yevos dpLolcos €;^etv 
1 (tov) Ogle. 

" Apparently because the objects with which it deals are 
more " corporeal " than those of the other senses — it has 
to be in bodily contact with them. 

* As apart from a priori reasoning. 

" Sometimes, as here, " counterpart " could be represented 
by the modern term " analogue." 

^ Lit., " the soft-shelled creatures." 


the medium of the sensation combined in one (com- 
parable to the pupil plus the whole of the transparent 
medium in the case of sic^ht). Now not only was it 
pointless, it was impossible for Nature to make such 
a combination in the case of the other senses ; with 
touch, however, it was due to necessity, since its 
sense-organ is the only one which is corporeal — 
or at least it is definitely the most corporeal one." 
It is also clear from our actual experience in sensation^ 
that all the other parts exist for the sake of the organ 
of touch (the flesh). In these I include the bones, the 
skin, the sinews, the blood-vessels ; also the hair, nails 
of every sort and kind, and the like. The bones, 
for instance, which are hard in substance, have been 
devised for the preservation of the soft parts. The 
same is true of the counterpart ^ of the bones in other 
creatures : two examples in species of fish are spine 
and cartilage. 

Now with some animals this hard supporting 
substance is situated inside the body, with others 
(some of the bloodless ones) it is outside. It is out- 
side in the case of all the Crustacea ^ {e.g. the Crabs 
and the group of Crayfish), and the group of Testacea* 
too, e.g. those that are known as Oysters. All these 
have their fleshy part inside, and the earthy part 
which holds it together and protects it is out- 
side — outside, because it performs an additional 
function as well : since these creatures are bloodless, 
they possess but little heat, and the shell acts like 
a couvre-feu ; it encloses the faintly burning heat 
and protects it. Another quite different group of 
creatures, the Turtles and the group of freshwater 

* Lit., "the shell-skinned creatures." "Testacea" is the 
nearest modern term. See Introduction, p. 23. 



654a ^ ^ 

OoKeZ TOVTOLS, erepov 6v yivos toutojv. to. 8* 

10 cvrofia tujv l,tpojv /cat ra fiaXaKLa rovrois r 
evavTLOis Koi avrols avrt/cet/xe't'cos" avvearrjKev ovBev 
yap ocrtoSe? ^X^'-^ eoLKev ovSe yerjpov dnoKeKpL- 
fievoVf 6 TL /cat aftov etVetv, dXXa rd fxev juaAa/cta 
ax^^ov oXa aapKcoSr] /cat /xaAa/ca, 77/30? oe to {xtj 
€V(f)6apTOV elvai to acofjia avrojv, KaOdrrep rd 

15 GapKcoSr), fiera^v aapKos /cat vevpou ttjv (f)VGLV e;^et. 
jLtaAa/coi/ jLtey yap ojGTrep adp^ euriv, ex^i 8e rdoiv 
woirep vevpov rrjv 3e ax^cri'V '^X^^ '^1^ aapKos ov 
Kar €vdvojpiav dXXd Kara kvkXovs hLaiperrjv 
OVTOJ? ydp [av]^ ^X^^ XPV^^H'^'''^'^^^ ^^ ^'^V^ Trpos ttju 

20 Icrxvv. VTrapx^L 8' eV auTot? Kal to amAoyov Tat? 
TOJV IxOvcov aKavdais, otov iv fiev Tat? (jrjTTLaLS to 
KaXovfievov otjttlov, iv 8e Tat? revdiGL rd koXov- 
fievov ^Lcf)og. rd^ 8' av tojv ttoXvttoSojv (yevo^y* 
TOLOVTOV ovSev ex^t- 8td to [xiKpov ^x^lv rd kvtos 
rrjv KaXovfxevTjv K€(f)aX^v, ddrepa 8* cvfJLT^Kr]. Sto 
TTpds rrjv dpOorrjra avrcov /cat rrjv dKapufjiav vtt- 

25 eypaipe ravra rj ^vuis, cjorrep r(x)v ivaipicjv rots 
fjL€v OGTOvv rots 8' aKavdav. rd 8* evrojjia rovrois 
T ivavriojs e;)^et /cat Tot? eVat/xot?, KaOdnep etVojitev* 
ouSev ydp d^ojpLGpievov ep^et GKXrfpov, rd 8e fiaXa- 
KOVy dAA' oAov rd Gcofia GKXrjpoVy GKXrjporrjra 8e 
ToiavrrjVy oGrov fxev GapKCoSeGrepav, GapKos 8' 

^ [av] seclusi. * pfpT^CTt/ia^Ta-a €177 SU. 

3 TO Piatt : rd vulg. * {y^vos) Piatt 



Tortoises, are apparently in like case. On the other 
hand, the Insects and the Cephalopods are differ- 
ently constructed from these, as well as being 
different from each other. Not only, as it appears, 
have they no bony part, but they have practically 
no earthy part at all distinct from the rest of the 
body. The Cephalopods are almost wholly soft 
and fleshy, yet in order to prevent their bodies 
from being easily destructible as fleshy struc- 
tures are, the substance of which they are formed 
is intermediate between flesh and sinew, having the 
softness of flesh and the elasticity of sinew. When 
it is split up, it breaks as flesh does, that is, not 
longitudinally but into circular portions. The reason 
for this seems to be that such a structure secures 
the greatest strength. There is found also in these 
creatures the counterpart of the spinous bones of 
fishes ; examples are : the " pounce " (os sepiae) of 
the cuttlefish, and the " pen " (gladius) of the 
calamaries. Nothing of this sort, however, appears 
in the Octopuses : this is because in them what is 
called the " head " forms but a small sac, whereas 
in the cuttlefish and calamaries the " head " is of 
considerable length. So we see that, in order to 
secure that they should be straight and inflexible, 
nature prescribed for them this hard support, just 
as she gave to the blooded creatures bones or spines. 
Quite a different contrivance obtains in the Insects — 
different both from the Cephalopods and from the 
blooded creatures, as has already been stated. In 
the Insects we do not find the clear-cut distinction 
of hard parts and soft ; here, the whole body is hard, 
yet its hardness is such that it is more fleshlike than 



654 a ^ 

SO OGTcoZeoripav /cat yecohearepav, npos to /xtj eu- 

Bialperov etvat to crco/xa avrcov. 

IX. *'E;)^et S' ofioLOjg rj re rtDy ocrrcov /cat -j^ 

ra)V (fyXe^cbv ^voi£. e/carepa ydp avrayv dcf)^ eVos" 

TjpyiJLevr] ovvex'^S ecrrt, /cat owr' ocrrouy iariv avro 

85 /ca^' aiJTO ovhev, aAA' -^ pLopiov d)s avvexov? rj 

aiTTopievov /cat TrpoGSeSefievov, tva xprjrai rj (f)VGLS 

654 b /cat COS" eVt /cat auve;^et /cat c5? Sfcrt /cat Sir^pr^pievoLg 

irpOS TTjV KOijJUpLV. OfJiOLOJS 8 6 /Cat ^Acj/f ovSejJLLa 

» \ 

t^' auTTiv iuTLv, dXXa 

avrrj /cat; avrrjv eunv, aAAa Traoai fiopiov /Lttas" 
etcrtv. OCTTOUV re ydp et rt KexojpLGjJLevov rjv, to t* 

6 epyov ovK dv erroUi ov X^P*-^ V '^^^ ootcov eVrt 
(f)VGLs {ovTe yap dv Kapupecos rjv aiTiov ovt^ opdo- 
TTjTOs ouSe/xtas" fir) ovvex^? ov dAAd StaAetTrov), ert 
r e^XaTTTev dv caarrep aKavdd rts" rj jSeAos" ivov rat? 
aap^iv. etre ^Aei/f t^v rt? Kex^Jiipiopiivri /cat /LtT^ 
ovvex'^S rrpd's Trjv dpxrjv, ovk dv ecrco^e to iv avTjj 

10 atjLta* rj yap cxtt' eKeiviqs depixoTrjs KCoXvei TT-qyvv- 
adai, ^atVerat 8e /cat arjTTOjJievov to x^P^^opuevov. 
dpx^ Se TcDv jLt€V (f)X€^a)v rj Kaphia, rcuv 8' ocrrajv 7^ 
KaXovjjievrj pdx^S rols exovGLV ocrra TrduLV, d(f)^ rjg 
Gwex^jS rj Tcjjv dXXojv ogtwv €Gtl cJ)vgls' rj yap to 
jiTjKos /cat TTjv opOoTrjTa GvvexovGa tojv t^wcov rj 

16 pdx^S eGTLV, eTTel 8' dvdyKrj Kivovfjudvov tov ^ojov 

PARTS OF ANIMALS, II. viii.-ix. 

bone is and more bony and earthy than flesh. The 
purpose of this is to ensure that the body shall not 
easily break up. 

IX. The system of the bones is similar to that of Bonea. 
the blood-vessels : each is a connected system begin- 
ning from one point. There is no such thing as a 
bone by itself in isolation ; every bone is either 
actually part of the connected scheme, or else is 
attached to it and so is in contact with it. This 
enables Nature to use any couple of bones either 
as a single connected piece, or, when flexion is 
required, as two distinct pieces. In like manner, 
there is no such thing as a blood-vessel by itself in 
isolation : they are all of them parts of one blood- 
vessel. An isolated bone could never discharge the 
function for which all bones exist ; for, being dis- 
continuous and disconnected from the rest, it could 
never serve as the means either for bending or for 
straightening a limb ; but worse than that, it would 
be a source of harm, like a thorn or an arrow sticking 
in the flesh. Similarly, if we imagine a blood-vessel 
isolated and not connected with the source of them 
all, it could never keep the blood within it in a proper 
condition, since it is the heat which comes from that 
source which prevents the blood from congeahng, as 
is shown by the putrefaction of blood when separ- 
ated from it. This source of the blood-vessels 
is of course the heart, and the corresponding source 
of the bones in all bony species is what is called the 
backbone. The system of the bones is a connected 
whole, starting from the backbone, since the back- 
bone connects together the length of the animal's 
body and holds it straight. Now although this back- 
bone is a unity because it is connected together, it 

f2 163 


654 b ^ 

KdfjLTTTeoOaL TO CTcojua, jJLLa ji€v Slol TTjV ovve)(€iav 

ioTL, TToXvfJLcprj^ §6 ttj hiaipia^i rcov ottovSvXcov . 
CK 8e ravTrjs toZs e^ovGi KcoXa Gvvexrj [npos avrrjv] 
ra TOVTOJV Sard [rcoy apfiovLcov] eoriv ra} fiev [e;(et 
TO, KwXa KajjufjLV GvvSeSejjLeva tols^ vevpoLg, Kal] rcov 

20 eo-xdrcjov ovvappLorrovTCjov , rod p.ev ovros kolXov 
Tov Se 7TepL(f)€povs, ^ Kal ajJL(f)OT€pci)v KOiXcov, iv 
fiecjcp be 7TepieiXr](j)6Ta>v y olov yojJLcfiOV, darpdyaXov, 
tva yivqrai Kdpujjis /cat eKrauLs (aAAcus* yap rj oXojg 
dSvvarov, tj ov KaXaJg dv eTTOLOVv ttjv TOLavrr]v kl- 
vrjaLv)' eVta S' avTcov ojioiav exovra r-qv dpx'^v ttjv 

25 Baripov rfj reXevrfj Oarepov [ovvSeSeTau vevpoLs]'^ 
Kal x'^vhpcxjhri he piopia fiera^v rcov Kdpupecov 

eOTlv/ olov UTOLp-q, TTpOS TO dXXvjXa (JLT) TpL^eiV. 

Hepl Se TO, oCTTa at adpKeg TrepLTrecJyvKaGL, 

TTpoaeiXrjpLpievai XeTTTol? Kal IvcjSeai Secr/xots"* ojv 

eveKev to tcov ogtcov ecrrt yevos. wunep yap ol 

80 TrXdTTOVTes eK tttjXov ^wov yj tlvos dXXrj^ vypd? 

avGTdaecos xx^iGrdoi rcov arepeojv n acofidTajv, etO^ 


heSrjfjLLOvpyrjKev eK rcov oapKCJV to ^a)OV. tols 

fxev ovv aAAois" vireoTiv octtcl rots' GapKcoSeai /xo- 

piois, Tols fJiev Kivovp,evoi£ Sta Kdiiiptv tovtov 

35 x^pLV, Tols S' dKivqTOis (f)vXaK7Js eveKev , olov at 

655 a ovyKXeiovuai jrXevpal to orrjOos oojTrjpias X^P^^ 

^ TO. Peck : TO? Z : fj vulg'. : ooto. tcjv [xopicov iariv ras fieu 
(^ fiev vulg.) €X€L TO. KojXa Kal KafupLV Z. 

^ TOLS SU : re vulg. : ye EY. 

^ 11. 16-25: hunc locum correxi, partim 2 et Albertum 
secutus. vid. p. 46. fortasse et cVei 8' dvay^ij . . . anov 
SvXcov (11. 14-16) secludenda. 

* elaiv vulg. 



is also a thing of many parts because of its division 
into vertebrae, since the body must be able to bend 
while the animal is in motion. And the bones of the 
various limbs (in those animals which have them) 
are connected with this backbone, from which they 
originate. Some of them have extremities which fit 
on to each other : either (a) one is hollow and the 
other rounded, or (h) both are hollow and hold a 
huckle-bone between them (as it might be a bolt), 
to admit of bending and extension, since these 
movements would be quite impossible or at any rate 
unsatisfactory ^^'ithout such an arrangement, (c) 
There are some joints in which the adjacent ends of 
the two bones are similar in shape ; [these are bound 
together by sinews,] and there are pieces of cartilage 
inserted in between them, like a pad, to prevent 
them from rubbing against each other," 

Now the w^hole system of the bones exists to sub- 
serve the fleshy parts of the body, which have their 
place around the bones and are attached to them by 
thin fibrous threads. Modellers who set out to mould 
an animal out of clay or some other plastic substance 
begin first of all with a hard and solid core and mould 
their figure round it. Nature's method has been the 
same in fashioning animals out of flesh. With one 
exception, all the fleshy parts have a core of bone : 
for the parts that move and bend, this is present as 
a means for enabling the limb to bend ; for those 
that do not move, it serves as a protection : an 
example of this are the ribs, enclosing the chest, 
which are a means of protection for the viscera in 

" The text of this paragraph has been confused by a 
number of interpolations, most of which I have omitted in 



655 a ^ XX , , X X X X 

TcDv Trepl tt^v Kaphiav OTrXdyxvcov ra 8e Trept tt^v 

KOiXtav dvoGTea Trdoiv, ottco? firj KCjoXvr) rrfv av- 

oih-quiv TTjv 0,770 rrjs rpO(f)rjg yivofievr^v rot? t,o)Ois 

i^ dvdyK-qg /cat roX? di^Xecn rrjv iv avrol? rcbv ifi- 

6 To. jjiev ovv ^ojOTo/ca rtuy ^cocov /cat iv avrdls /^cit 
^KTOS TrapaTrXrjGLav e;^et ttjv tcov ogtwv BvvafJLLV /cat 
LGXupdv. TToXv yap /xet^co navra rd roiavra rdv 
fiT] i^ojoTOKOJv CO? /card Xoyov elrreiv ra)V GOJfxarojv' 
6VLa)(ov yap ttoAAo, ytverat fieydXa rcbv ^cootokojv, 

10 OLOV iv Ai^vrj Kal rots tottols tols depfioXs /cat rot? 
^TjpoXg. rots' S^ jJLeydXoig LGxvporipojv Set rcov 
VTrepeiGixdrajv /cat fjiei^ovojv /cat GKXrjporlpcjv, /cat 
TOi;ra;v auroiy rot? ^LaGriKcoripois. hid rd rcbv 
dppivojv GKXiqporepa t) ret rcov OrjXetcov, /cat rd rcov 
aapKO(f)dya)v [r] rpo(l>r) ydp Std pLax^]? rovrois), 
a)G7T€p rd rod Xeovros' ovrco ydp ^x^^ ravra 

15 GKXfjpdv rrjv (J>vglv ojGr i^drrreGdai rvTrropbdvcov 
Kaddrrep e/c XiOojv TTVp. e;Y€t Se /cat o SeA^ts" ou/c 
aKavdag dAA' oora- Jworo/co? ycip iGriv. 

Tots' S' fcVat/xots" ftev jLtT7 ^cooro/cots' 3e Trap- 
aAAdrret /card puKpov r) <J)Vgls, olov roZs opviGiv 
oGrd jLteV, dGOeviGrepa Se. rcDv 8* IxOvcov rots pL€v 

20 cporoKOLs aKavda, /cat rots' d<j)€GLV aKavdwSrjs iGrlv 
T) rcbv oGrcbv (f)VGi£, TrXrjV rolg Xiav /xeydAots" rov- 
roLs Se, St' d'Trep /cat rots' ^cporoKOis, Trpos rr)v 
LGxvv LGXvporepcov Set rcbv Grepeojfidrojv. rd Se 
KaXovfjLeva oeXdxf] ^oJ^Spd/cai^^a r^v (J)vglv eGnv 
vyporepav re ydp dvayKalov avrcbv elvai rrjv kl- 

<» Cartilaginous fishes, including the sharks. 


the region of the heart. The exception is the parts 
near the belly, which in all animals are boneless. 
The purpose of this is that the swelling which takes 
place of necessity after the receipt of nourishment 
may not be hampered, and (in females) to prevent 
any interference with the growth of the fetus. 

The nature of the bones is similar in all viviparous 
animals (that is, internally viviparous as well as 
externally) ; and as the Vivipara are much larger 
proportionately in bodily size than other animals, 
their bones are strong. In some places many of these 
animals grow to a great size, as for example in Libya 
and other hot dry countries. These large animals 
need stronger and bigger and harder supports, 
especially those of them that are particularly violent 
in their habits. Hence, the bones of males are harder 
than tlie bones of females, and those of carnivorous 
animals than those of herbivorous, because the car- 
nivorous have to fight for their food. An example 
is the Lion : it has such hard bones that when they 
are struck fire is kindled as it is from stones. Note 
that the Dolphin, being viviparous, has bones like the 
other viviparous creatures, and not fish-spines. 

In the creatures which though blooded are not 
viviparous Nature has made a series of graduated 
changes : for example, birds have bones, but they 
are weaker than the bones of the Vivipara. The 
oviparous fishes have fish-spine, not bone ; and the 
serpents have bone whose nature is that of fish-spine ; 
except the very large species, and they have bones, 
because (just like the Vivipara) if their bodies are 
to be strong the solid framework of them must be 
stronger. The creatures called Selachia " have spines 
made of cartilage. This is because their movement 



655 a 

25 vTjaiVy coare Set Kal ttjv tojv epeiGjJidrcov firj Kpav' 

pov elvai aAAa fiaXaKcorepav, Kal to yecoSes ets" 
TO Sepfia TTOLV avriXcoKev rj ^vgis' a'fta 8e ttjv avrrjv 
V7T€po-)(r]v els TToXXovs TOTTOVs dSwarei 8taye/xetv rj 
<f)V(jLS. €V€OTi he Kal iv rols t^cooroKois ttoAAo. tojv 
OCTTCov xov^p(J^hr], iv octols ovii(f>epei [JuaXaKov etvai 

80 Kal fiv^ojSes^ TO OTepeov hid tj]v odpKa ttjv nepi- 
K€Lfievr]v, OLOV GVfjL^e^rjKe Trepi re ra cora /cat 
Tovs fjLVKTrjpas' dpaveTai ydp Ta Kpavpa TaxioiS 
iv Tois direxovaLv. r) he cJjvgls tj avTrj x^^^P^^ 
Kal OGTOV iGTLy hia^ipei he to) jJidXXov Kal rJTTOV 
Sto Kal ovheTepov av^dveTai d-noKOTTev. 

85 Ot ixev ovv iv Tols TTe^ots a/xueAot x^^^P^^ kcxo)- 
pLGfievo) fjLveXcp' to yap ;)(a)pt ^o/xevov ets* dnav 
pLepayixevov fiaXaKTjv iroiel Kal fxv^ojhrf ttjv tov 
xdvhpov GVGTaGLV. iv he rot? oeXdx^GLV rj pdx^S 
655 b x^^^P^^^^S" piiv ioTLv, ex^L he fiveXov dvT* ogtov 
ydp avTOis VTrdpx^i- tovto to jiopLov. 

^vveyyvs Se /caret ttjv d(j)7]v eVrt rot? ogtoXs koI 
TO, TotaSe Tcjv jiopiajVy olov ovvxis re /cat OTrAat /cat 
X^jXal Kal KepaTa Kal pvyx^] to, rcuy opvidoiv. navTa 
5 he TavTa ^orjOeias exovGi X^P^^ ['^^ ?^ct]'' ra ydp ef 
avTCov GVveoTrjKOTa oXa Kal Gvvcjvvjxa toZs jLtoptotS', 
olov ottXtj re dXrj Kal Kepas oXov, jjLefjirjxdvrjTat, irpos 
TTjv GCJTTjpiav eKdoTOis. iv TOVTCp he to) yevei /cat 

^ ^u/uD8e? Z. ^ ^v^iathr) EPSZ. 

^ [ra ^a)a] secludit Rackham. 

*• Cf. the " law of organic equivalents." 
^ See note on 644 a 17. 


has to be somewhat supple, and accordingly the 
supporting framework of their bodies must be some- 
what pliable, not brittle. In addition. Nature cannot 
allot the same plentiful supply of any one substance 
to many different parts of the body ; ° and in the case 
of the Selachia she has used up all the available earthy 
substance in constructing their skin. In the Vivipara 
too there are many instances of cartilaginous bones : 
they are found where it is an advantage that the 
solid framework should be pliable and glutinous for 
the benefit of the flesh that surrounds them. This 
applies to the ears and the nostrils. Such projecting 
parts quickly get broken if they are brittle. Car- 
tilage and bone are the same in kind and differ 
only by " the more and less " ^ ; so neither of them 
continues to grow when it has been cut out of the 
living organism. 

The cartilages of land -animals contain no marrow — 
that is, no marrow existing as a separate thing. 
What in ordinary bones is separable is here mixed 
in with the body of the cartilage and gives it its 
pliable and glutinous character. In the Selachia, 
however, although the backbone is cartilaginous it 
contains marrow, because it stands to these creatures 
in place of a bone. 

The following substances or ** parts " resemble 
bones very closely as regards their feel : the various 
sorts of nail ; hoof and talon ; horn, and beak. 
All these substances are present for the sake of self- 
defence. This is shown by the fact that the complete 
structures which are made out of them and bear the 
same names — e.g. the complete hoof, or horn — have 
been contrived in each case by Nature for the creature's 
self-preservation. We must reckon the teeth in this 



655b ^ ^ ^ ^ 

T] Tojv oSoi'TCov earl (j)VGis, rols fJLev vnap^ovaa 

10 TTpos €v epyov rrjv rrj? rpocfirjg Ipyaaiav, rolg he 
TTpos re TOVTO Kal irpos aXKrjv, olov rolg Kapxap- 
oSovGi Kal x^vXiohovuL TTaaiv. e^ avayKiqs Se 
TTOLvra ravra yecohrj Kal orepeav exec ttjv (f)VGLV' 
ottXov yap avrrj Svvajjug. 8to /cat Trdvra to. rotaura 
pidWov ev TOts" rerpaTTOGLV virapx^t' ^4^ol9 rcov 

15 ^(xjoTOKOJV, Sta TO yewheoTepav €;^etv TTai'ra rrfv 
G-uoraaiv t) to rcov avdpojTTOJV yevos. aXXa Kal 
TTepl rovra>v Kal rcov exojJLevatv, olov Sepjjiarog Kal 
KVGTecDs^ Kal vfievo? Kal rpix^v Kal Trrepajv Kai 
TOJV avdXoyov rovrois Kal e'i ri roiovrov eari fjiepos, 
varepov djjia rots dvopiOioixepeoL 6ea>prjreov rrjv 

20 alrlav avrcov, Kal rivos eveKev vnapx^i tols ^cool? 
eKaarov eK rcov epyojv yap yvwpit^eiv, axmep 
KOiKetva, Kal ravra dvayKatov dv elr]. dXX on 
avvajvvfJLa rols oXois rd fi^py], ttjv rd^iv dneXa^ev 
iv rot? ofiOLoixepeoi vvv. elal S' dpxoil Trdvrcjv 
Tovrojv TO T€ oorovv Kal r] odp^. en he rrepl 
yovrj? Kal ydXaKros direXiTTop.ev ev rfj Tvepl rwv 

25 vypwv Kal 6pLOiopL€pa)V decupia- rols yap Trepl 
yeveaeojs Xoyois dpfxorrovoav e;^et rr)v CKeipLv ro 
fjL€V yap avra>v dpx^ 'to 8e rpocjij] rcjv yLvofievajv 

X. Nw 8e XeyojpLev otov dn^ ^PXV^ ndXiv, dp^d- 
jJLevoL TTpcbrov dTTo rcov TTpcorojv. irdoi yap rols 

^ aKvreos Buss. {oKvreojs EY), 


class too. In some creatures teeth are present to 
discharge one function only — viz. mastication ; in 
others they are a means of force as well {e.g. 
sawlike teeth and tusks). All these parts are 
of necessity earthy and solid in character ; that 
is the proper sort of substance for a weapon. 
So there is a tendency for all parts of this sort to 
appear in the four-footed X'^ivipara more extensively 
than in man, because the former all have more earthy 
matter in their constitution. We shall, however, con- 
sider these substances, and the other kindred ones 
such as skin, bladder, membrane, hair, feather, and 
the counterparts of them, and all such parts, when 
we come to deal with the non-uniform parts. Then 
also we shall consider the Causes of them and for 
what purpose each of them is present in animal bodies ; 
since it is true to say, of both sets of things, that our 
knowledge of them must be derived from a study of 
the functions which they discharge. The reason why 
we have just been taking them with the uniform 
substances and out of their proper order is that in 
them the name of the complete structure is the same 
as that of a portion of it, and also because the sources 
and principles of them all are bone and flesh. We 
also left out all mention of semen and milk \vhen we 
were considering the fluid uniform substances. As 
semen is the source of the things that are generated 
and milk is the food that feeds them, the proper place 
to discuss these is in the treatise dealing with 

X. We may now make what is practically a fresh The non- 
beginning. We will begin first of all with the things paJ.tJ'^'^ 
that come first in importance. 



655 b 5 / r / 

30 ^cpoLS rols TeXelois^ Svo ra avayKaiorara fiopia 
ioriv, fj re SexovraL rrjv Tpo(f)rjv /cat 7^ ro TrepLTTOjfia 
dchtdaLv^- ovre yap elwai ovre av^dveoOai ivSex^rai 
dv€v rpo(f)rj?. [rd pLev ovv cfyvrd — /cat ydp ravra l,rjv 
cjiapev — Tov ptev dxp'qcrrov TTepLrrajpLaros ovk €X€L 

85 TOTTOV ei< rrj? yrjs ydp XapL^dvet TTeirepLpiiirqv ty]v 
Tpo(f)7^v, dvTL he rovTOV rrpoterai rd GneppLara /cat 
Tous" KapTTOvs.) TpLTOV 8e pLepo9 eV Trdalv eon to 
Tovrcjv pieoov, ev (L rj dpx'q eonv 7) ttjs ^Ci)y]9. rj 

656 a pueV ovv TOJV (f)VTCOV (f>VOL? OVOa pLOVLpLOS OV TToXv- 

etSr^S" eoTt rcov dvojxoLopepibv Trpos ydp oXiyag 
TTpd^eis oXiycov opydvcov rj XPV^^^' ^^^ 6ecopr]reov 
Kad^ avrd Trepl ttjs tSea? avTOJV. rd Se Trpos Tcp 
t^rjv aioOrjoiv exovra 7ToXvpiop(f)orepav ex€L ttjv 
5 Iheav, /cat tovtojv erepa rrpd erepojv pidXXov, /cat 
TToXvxovorepav oocov pLTj pLovov rod i^rjv dXXd /cat 
rod ev t/qv rj (j>voLS pieTeLXrj(f)ev. tolovto 8* eorl rd 
TU)V dvdpcoTTOJV yevos' ri ydp pLovov ju,ere;\;et rod 
Beiov rojv rjpuv yvajpipLCov ^wcov, rj pidXiora Travrajv. 
wore Sid re rovro, /cat 8ta to yvcopipLov elvai 
10 pidXior avrov rrjv rwv e^codev pLOpiojv piop(j)tjv, 
TTepl rovrov XeKreov rrpcorov. evdvs ydp /cat to, 
<f)Voei pLopia Kard <j>voLV ex^i' rovrco pLovco, /cat rd 

^ Tot? TcAetots' Peck : rots ye t. Ogle : /cal TeAeioy/xeVots kox 
TcAet'oi? Piatt : koX reAeiots vulg:. 
^ d(f)idat,v SUY : a(f)-qaovaLV alii. 

« These three parts of the " perfect " animals are again 
referred to at De juv, et sen. 468 a 13 ff. At De gen. an, 



An animal can neither exist nor grow without food. 
Therefore in all living creatures of perfect formation <* 
there are two parts most necessary above all : one by 
which food is taken in and the other by which residues 
are eliminated. (Plants — which also we include 
under the head of living things — have, it is true, no 
place for the useless residue, but this is because their 
food, M'hich they get out of the earth, is already con- 
cocted before it enters them, and instead of this 
residue they yield their fruit and seeds.) And in all 
creatures there is a third part intermediate between 
these indispensable two, and this is the seat of the 
source and principle of life. Plants, again, are so made 
as to remain in one place, and thus they do not exhibit 
a great variety of non-uniform substances ; they have 
few actions to perform, and therefore but few organs 
are needed to perform them. For this reason we must 
consider plants and their formations separately. But 
with creatures that not only live but also have the 
power of sensation, the formations are more varied, 
and there is more diversity in some than in others, the 
greatest variety being found in those creatures which 
in addition to living have the capability of living the 
good life, as man has. Man is the only one of the 
animals known to us who has something of the di\'ine 
in him, or if there are others, he has most. This is 
one reason why we ought to speak about man first, 
and another is that the shape of his external parts is 
better kno\vnthan that of other animals. Another and 
obvious reason is that in man and in man alone do the 
natural parts appear in their natural situation : the 

733 b 1 and 737 b 16, 26, the " perfect " animals are the 
viviparous ones. For the " most highly finished " animals 
see 666 a 28. 



656 a ^ « ,/ ,/ V f \ 

TOVTOV avco irpos ro rod oXov e;^et avw [lovov yap 

OpOoV €GTL rOJV t,(l)Cx)V avdpCjDTTOS . 

To /xev ovv ex^LV ttjv Ke(f)aXrjv aoapKOV €K tojv 
15 776/31 Tov lyKe^aXov elprjiJLevcov dvayKOLOV avfi- 
^€^r]K€V. ov yap woirep rivks XeyovGLV, otl et 
oapKajh-qs riv, fiaKpo^iCJTepov av '^v to yevog, 
oAA* evaiod-qoias eVe/cev aoapKov elvai <f)auLV 
aloddveoOai fiev yap rep iyK€(f)dX(p, ttjv S' alodr]Giv 
ov TTpooUuOai rd pLopia rd uapKcoSr] Xiav. TOvra>v 
20 S' ovSerepov eariv dXrjdes, dXXd TToXvaapKOS ftev 
o TOTTos (J^v 6 TTepl Tov €yK€(f)aXov Tovvavriov av 

d7T€Lpyd^€TO ov eV€Ka V7Tdp)(€i ToXg ^CpOLS 6 €y- 

KecjiaXos {ov ydp av eSuVaro KaTaijjv-x_€iv dXeaivojv 
avTos Xiav), tojv r aiGOiqaeajv ovk alrios ovhep,idSy 
OS ye dva'iad'qros Kal avros Igtiv ojUTrep oriovv 
25 TOJV TTepLTTCOfjLdrcov. dAA' ovx evpioKovres hid 
TLva alriav eVtat rwv aloQ-qaeajv iv ttj K€(f)aXfj 
ToZs t,(jjoLs €LGL, TOVTO 8' opcovTes IhiaiTepov ov 
TOiv oKkojv p^opLCDv, CK GvXXoyLOfiov 7Tp6? dXXrjXa 
avvSvd^ovGLv. OTL fi€v ovv dpx'Q ra>v alGd'qaecjv 

€GTIV 6 TTepl TTjV KaphiaV TOTTOS, hlOjpLGTai TTpO- 

Tepov iv ToZs TTepl alGdrjGeojs , Kal Slotl at jjiev Svo 

80 ^avepojs rjpTrjfjLevaL TTpds ttjv Kaphiav €lglv, rj re 

Tcov aTTTwv Kal rj tojv x^fxdjVy tGjv 8e Tpiojv y] jxev 

TTJS OG(f)prjG€OJS IxiGt), dKOYj Sc Kal OlJjiS pdXiGT €V 

Tjj K€<^aXfj hid TTjv TOJV aiGdriTiqpiajv <f)VGLV eiGL, Kal 

" See the identical phrase in De resp. 477 a 22. 
" Cf. Plato, Timaeus 75 a-c. 


upper part of man is placed towards the upper part 
of the universe.^ In other words, man is the only 
animal that stands upright. 

In man, the head is lacking in flesh, and this follows of the 
of necessity from what we have said about the brain. gra^'aJJi® 
Some ^ say (erroneously) that if the head abounded Sense- 
wlth flesh mankind's lifespan would be longer than °^s^^^- 
it is, and they explain the absence of flesh as on pur- 
pose to facilitate sensation, their view being that the 
brain is the organ of sensation, and that sensation 
cannot penetrate parts that are too fleshy. Neither 
of these assertions is true. The truth is that if 
the part surrounding the brain were fleshy, the 
effect of the brain would be the very reverse 
of that for which it is intended : it w^ould be 
unable to cool the rest of the body because it would 
be too hot itself. And, of course, the brain is not 
responsible for any of the sensations at all ; it has no 
more power of sensation than any of the residues. 
People adopt these erroneous views because they are 
unable to discover the reason why some of the senses 
are placed in the head ; but they see that the head 
is a somewhat unusual part, compared with the rest, 
so they put two and two together and argue that 
the brain is the seat of sensation. The correct view, 
that the seat and source of sensation is the region 
of the heart, has already been set forth in the treatise 
Of Sensation/' where also I show why it is that two of 
the senses, touch and taste, are evidently connected 
to the heart ; of the remaining three, smell is placed 
between the other two, hearing and sight, and these 
are practically always located in the head : this is 
owing to the nature of the organs through which 

• De sensu, 438 b 25 flf. 



656 a 

Tovrojv rj oipLs ttololv' inel rj y olkotj /cat -q oa^prjOLS 

35 ezrt rcov l-)(dv(x)V /cat rcov roiovrojv Troiet ro Aeyo- 

[jL€vov (f}av€p6v' OLKovovGL fikv yap /cat oocj^paivovTai, 

alad-qr-qpLov 8' ovSev exovai <j>avep6v iv rfj Kecf)aXfj 

rovTOJV tCjv alo6rjT(2)v} rj 8' oj/rt? 77-ao-t rot? e^ovaiv 

656 b €v\6yois iorrl rrepl rov eyKe(f)aXov 6 jxev yap vypos 

/cat ifjvxpo?, rj 8' vSwp ttjv (f)vaLV eoTiv rovro yap 

Tcov SLa(f)ava)V evcfyvXaKTorarov Igtiv. ert 8e ra? 

oLKpL^earepas tcov alodriGewv 8ta tojv Kadapajrepov 

ixovTWv TO at/xa piopiojv avayKaiov a/cpt^ecrrepas' 

5 yiveudai- eKKOTTTei yap rj Trjs ev tw atjxaTi dep- 

jxoTrjTOS KLvr]aL<i ttjv alaOrjTLKrjV ivipy €iav' 8ta 

Tavras ras" atrta? ev ttj K€cf)aXfj toijtcjov to. aloOrj- 

TTj ptd ioTiv. 

Ov fjLovov 8' ecrrt to epLirpoGdev aoapKov, dAAo, to 
OTTLodev TTJs KecfiaXrjS, 8td to Trdui rots' ^xovglv 
avTrjv opdoTaTOV heZv elvai tovto to fxopLov ovSev 
10 yap opdovaOai SvvaTai cfiopTLOV ^xov, rjv 8' av 
TOiovTOV, el G€GapKa>fxevrjv elx^ Trjv Ke<^aX'iqv, fj /cat 
SrjXov OTi ov Trjs tov iyK€cf)dXov alad-^Geats X^P^^ 
aGapKO$ rj K€(j)aXrj ecrrtv to yap orriGdev ovk ex^L 
iyKecjiaXov, aGapKov 8' ojxolcjjs. 

''E;\;et 8e /cat ttjv aKorjv evXoycos evia tcov ^cocov 

15 €V TO) TOTTCp TCp 7T€pl TTjV Ke(f)aX'^V TO ydp K€v6v 

KaXovfxevov depos TrXrjpes eGTL, to 8e Trjs dKorjs 
alGdrjTrjpiov dipos elvai ^ajiev, 

^ (eVel . . . aloOrjTwv) Cook Wilson, qui et {ov) post 
Aeyofxcvov, 1. 35. 



they operate. Sight is always located there. The 
case of hearing and smell in fishes and the like 
shows that the opinion I maintain is patently correct. 
These creatures hear and smell, although they have 
no obvious and visible organs for these senses in the 
head. As for sight, it is reasonable enough that 
when present it should always be located near the 
brain, for the brain is fluid and cold, and the sense- 
organ of sight is identical in its nature with water, 
which of all transparent substances is the easiest to 
keep confined. Again, those senses which are in- 
tended for more precise work than the others must 
necessarily receive greater precision by being situ- 
ated in parts where the blood is specially pure, since 
the movement of the heat in the blood ousts the 
activity appropriate to sensation. These are the 
reasons why the organs of these senses are placed in 
the head. 

Now the back of the head is free from fleshiness as 
well as the front. This is because the head is the 
part which all animals that possess one have to hold 
as upright as possible. Nothing that carries a burden 
can raise itself upright, and the head would be 
burdened if it were well covered ^\dth flesh. And 
this is another reason to show that the lack of flesh 
on the head is not for the purpose of enabling the 
brain to function in sensation. There is no brain in 
the back of the head, although the back has no more 
flesh on it than the front. 

Some animals have their organ of hearing as well 
as of sight located in the region of the head. This is 
well explained on our view, which is that the organ 
of hearing is of air. The space in the head called the 
vacuum is full of air. 



656 b 

'Ek: jJLev ovv tcov ocjidaXiJLcov ol rropoi cpepovGLV et? 

TCLS Trepl Tov iyKecfiaXov ^Ae/3a?* ttolXlv 8* c/c rcbv 
(jjTOJv ojoavrojs TTopos et? rovTriaOev ovvaTrrei. 
["EcTTt S' ovr dvaif-LOV ovSev aladiqriKov ovre ro 

20 alfxa, dXXa rojv eV tovtov tl. hionep ovhev iv 
rots ivalpLOis dvaifjiov aLadrjriKov, ouS' auro to 
alpLo}- ovhev ydp tcov Jojcov /xoptov.]'* 

''E;^et 8' ev rol efiTrpoaOev tov iyKe(l>aXov TrdvTa 
TO. exovTa tovto to pLopiov, hid to efx-npoodev 
elvai i(f)^ o alaOdveTai, ttjv 8' aluO'qoiv diro ttj^ 

25 Kaphia?, TavTrjv 8' etvat eV rot? epLTrpoaOev, Kal 
TO aladdveadac hid tujv evalficjov yiveodai jjiopLOJV, 
(ffXe^dJv 8' elvai k€v6v to oTnodev kvtos. rera/crat 
Se TOV TpoTTOV TOVTOV TO, alodrjTripia ttj (fivaei 
KaXcbg, Td fJLev Trjs dK07]s eirl fxeorj^ ttj? '7T€pi^€peias 
[aKovei ydp ov fxovov /car' evdvcxjpiav dXXd ndv- 

80 Todev), Tj 8' 6ipi£ €1? TO efjLTTpoaOev {dpa ydp /car 
evdvcoptaVy rj he Kivqais els to e/JLTTpoadev, npoopdv 
he hel e(f)^ o r) Kivqai?). rj he Trjs oGcfypyjaeajs 
(xeTa^v TOJv d/x/xarcov evXoycDS. hnrXovv fiev ydp 
€GTLV eKaoTov Tcjv aiG O'qTTjplojv hid TO hiTrXovv 
etvai TO GQjfjLa, to fxev he^tov to 8* dpiGTepov. eVt 

86 /xev ovv TT^s d(f>rjs tovt dhrjXov tovtov 8' atrtov 
OTL ovK ecrrt to npcoTov alGdt^TiqpLOV rj Gdpi Kal to 
TOLOVTOV fxopiov, dXX ivTos . errl he Trjg yXojTTTjs 
•^TTOV fieVj {xaXXov 8' rj eirl ttjs d(f)r]S' eoTL yap olov 

* ovh* avTO TO at/ia om. E. 

" 11. 19-22 scclusi (20-22 Ogle) : partim ex 666 a 16 trans- 

" This passage seems to be a note on a remark which comes 
a few lines below, and should probably be omitted from the 
text. Part of it is taken from 666 a 16. 



Passages (or channels) run from the eyes to the 
blood-vessels that are round the brain. And, again, 
a passage runs from the ears and connects to the 
back of the brain. 

[No bloodless part is capable of sensation, nor 
indeed is the blood itself. It is the parts which are 
made out of blood that have this faculty. Hence, 
in the blooded animals, no bloodless part is capable 
of sensation, nor indeed is the blood itself, for it is 
no part of animals.] ^ 

The brain, whenever there is one, is in the forepart 
of the head. This is (a) because all acts of sensation 
take place in a forward direction ; (6) because the 
heart, from which sensation has its origin, is in the 
forepart of the body ; and (c) because the process 
of sensation depends upon parts that have blood 
in them, whereas the sac at the back of the head 
contains no blood-vessels at all. In fact. Nature 
has located the sense-organs in a very satisfactory 
manner. The ears are half-way round the circum- 
ference of the head, because they are to hear sounds 
from all directions alike and not only from straight 
before them. The eyes face front : this is because 
sight is along one straight line, and we must be able 
to see along the line in which we are moving, which 
is directly forward. The nostrils are between the 
eyes, and this is quite reasonable. Each of the 
sense-organs is double, because the body itself is 
double : it has a right side and a left side. It must 
be admitted that this duality is not at all clear in the 
case of touch : this is because the primary sense- 
organ of touch is not the flesh or a corresponding part, 
but something internal. With the tongue the duality 
is not very clear, but more so than with touch. 



657 a a(f)'q Tt? Kol avTYj r) aLGdrjaig. ofiojg 8e SrjXov Kal 
irrl ravTTjs' (f)aLV€TaL yap iuxLayLevq. errl he rcov 
aAAcov alaOiqrripicjv (jyavepcorepcDs iarlv rj aLoOrjuLS 
SijjLepij?- (Zrd re yap Svo Kal opLfxara Kal r) twv 
fjLVKTTipojv SvvapLLg SLcf)Vi]g ioriv. aXXov ovv av 

5 rpoTTOV K€Lji€vr] Kal Si€a7TaajJLevrj , Kaddnep rj rrjs 
aKorjg, ovK av iiroUi ro avri]? epyov, ovhe to 
fiopLov iv (L eaTiv Sta yap rrjs dvaTTVorjg r) aloQ-qGis 
rdls e)(ovGL fjLVKrrjpaSy rovro Se ro pLopiov Kara 
[leGov Kal iv rots efXTrpoadev iariv. hioirep et? 
jxeaov rojv rpicbv aiGdrjrrjplwv avvqyayev rj (f>VGLs 

10 Tovs jivKrrjpag, otov irrl ardOfxrjv Vetera fxlav em rrjv 
rrjs dvarrvorjs KivrjGiv. 

KaAcos" Se Kal rocs dXXoLS e^€i ravra rd alodrj- 
rrjpia t,cnois upos rrjv ISlav (jivaiv iKdurco. XI. 
rd jxkv yap rerpdnoSa dnrjprrjiJLdva €)(ei rd cora Kal 
dvojOev rojv 6jXfidra)v, cus" So^eiev av, ovk e;)^et Se, 

1^ dAAa (jiaiverai Sta to jxrj opBd elvai rd ^cpa dXXd 
KVTrrcLV. ovroj 8e to irXelarov Kcvovfievcov ;!^pT]o-t^a 
jjLer €0J pore pd r dvra Kal Kivovjieva' hex^^ai ydp 
Grpe(f)6fieva rrdvrodev rov£ ^6(^ovs jxdXXov. 

XII. 01 S' opviOes rovs rropovg povov e^ovGi hid 
rrjv rod hepjiaros GKXijporrjra Kal rd e^^iv jirj 

20 rptxcis dXXd TTrepcord elvac ovk ovv e^ei roiavrrjv 
vXrjv i^ rjs dv eVAaae rd ojra. ofiolajs he Kal rcov 

<» Aristotle seems to refer here to the forked tongues of 
certain animals. See 660 b 7 flF. 


(Taste, in fact, is itself, as it were, a sort of touch.) 
The duality is plain, however, even with this sense, 
for it is seen to be divided.^ With the other senses, 
the organ is more evidently parted into two : there 
are two ears and two eyes, and two passages for the 
nostrils in the nose. The sense of smell, if it had 
been other^^^se placed — separated into two, that is, 
like the sense of hearing — would not have been 
able to perform its proper function ; nor would 
that part of the body in which it is situated, since 
in animals which have nostrils, the sensation of 
smell is effected by means of inspiration, and this 
part is at the front and in the middle. This is 
why Nature has brought the nostrils together in a 
straight line and made them the central of the three 
sense-organs in the head, located where the motion 
of in-breathing takes place. 

In the other animals as well as in man these sense- Ears. 
organs are very satisfactorily arranged as required 
by the peculiar nature of each animal. XI. For 
instance, the quadrupeds have ears that stand out free 
from the head, and they are higher than the eyes — 
or appear to be, although this is not really so : it is 
an illusion due to the fact that these animals are not 
upright but stand on all fours. And as they are 
usually in this posture when in motion, it is useful for 
them to have their ears well up in the air, and also 
movable : this enables them to be turned round and 
oick up sounds better from all directions. 

XII. Birds have the auditory passages only, 
owing to the hardness of their skin, and because 
they have feathers instead of hair, which means that 
they have not got the right material for forming 
ears. The same argument applies to those oviparous 

181 ' 


657 a 

rerpaTToSojv to. cooroKa /cat ^oXihcxird' o yap avros 

apfioaei /cat eV eKcivcov Xoyos. ^x^l Se /cat t] 
(f)a)K7] Twv l^cpoTOKOJV ovK (JjTa dXXo. TTopovs dKorjs » 
hid TO TTeTTrjpcojjievov etvai rerpdiTOVv, 

25 XIII. Kat ol jLtev dvdpojTTOL /cat ol opviOes /cat rd 
t^cporoKa /cat rd cooroKa rwv rerpaTToSojv (f)vXaKr]v 
exovGL TTj? oipeojg, rd fxev ^cooroKa ^Xi(j>apa hvOy 
ols /cat oKaphapLvrrovai, rcjv 8' opvidcav dXXoi re 
/cat ol ^apels /cat rd cooroKa rd)v rerpaTTohcov rfj 

30 Karoj /3Ae</)aptSt pLVovoiv CT/capSa/xurroucrt 8' ot 
opvides e'/c TcDv KavddJv ujuevt. row //ev ouv (f)vXaKr]v 
€X€iv atVtov TO uypa to, opLfiara etvat tva ofu 
pXeTTCOdL [rovTov rov rporrov vtto rrjs <j)voecosf' 
GKX-qpoSepjJLa ydp ovra d^Xa^eorepa [lev dv rjv 
VTTO rd)V e^ojOev TTpooTTnrrovrcjv , ovk o^vcjoird Se. 
rovrov fxev ovv* eVe/ca Xerrrov ro Sep/xa to Trept 

35 Trjv Koprjv earl, rrj? Se ocxyrripias X^P^^ '^^ ^Xecfyapa- 
/cat 8td rovro orKapSap,vrr€L re Trdvra /cat p-dXior 
dvdpojTTOSy Trdvra piev ottcjos rd TrpouTrLTTrovra rols 
657 b ^Xe(j)dpoLs KcoXvajGt (/cat rovro ovk e/c Trpoaipeaeajs, 
dXX 7] (f)vaLg eTToirjcje), TrXeLaraKLs 8' o dvOpojTTos 
hid ro XeTTrohepporaros etvat. 

*H he ^Ae^apts" eoTt heppari TTepieiXrjppem]- hio 

/cat ov (jvp(f>verai ovre ^Xecbapis ovr' aKpoTTOodia, 

on dvev uapKo^ heppiard eoriv. 

5 Twv 8' opviOojv oCTOt rfi Kara) ^Xe(f)apihi jLtuouat, 

/cat rd cporoKa rojv rerpaTTohcoVf hid rrjv OKXrjpo- 

" Or, " imperfectly developed." Cf. Bk. III. ch. viii, 


PARTS OF ANIMALS, II. xii.-xiii. 

quadrupeds which have horny scales. One vivi- 
parous animal, tlie Seal, has no ears but only auditory 
passages ; but this is because, though a quadruped, 
it is deformed." 

XIII. Man, the Birds, and the Quadrupeds (both Eyes, 
viviparous and oviparous) have a protective covering 
for their eyes. The viviparous quadrupeds have 
two eyelids to each eye (which also enable them 
to blink) ; some of the birds, especially the heavily 
built ones, and the oviparous quadrupeds, when 
they close their eyes, do so with the lower eyelid ; 
birds, however, can blink, with the aid of a mem- 
brane that comes out of the corner of the eye. The 
reason for the existence of these protective cover- 
ings is that the eye is fluid in order to ensure 
keenness of vision. If the eye had been con- 
structed with a hard skin it would of course have 
been less liable to injury by impact from without, 
but its vision would have been duller. For this 
cause the skin round the pupil is left thin and fine, 
and the safety of the eye is ensured by the addition 
of the eyelids. The movement of the eyelids known 
as blinking is a natural and instinctive one, not 
dependent on the will, and its object is to prevent 
things from getting into the eyes. All animals 
that have eyelids do it, but human beings blink 
most of all, because they have the thinnest and 
finest skin. 

Now the eyelid is encased ^vith skin ; and that is 
why, like the tip of the foreskin, it \\'ill not unite 
again once it has been cut, because both of them 
are skin and contain no flesh. 

We said just now that some birds and the ovi- 
parous quadrupeds close the eye with the lower 

183 ' 


657 b 

rrjra rou Se/j/xaro? rod Trepl rrjv K€(f)aXrjv ovtcd 

fjLVovcTLV. oi fJLev yap f^apel<^ tcov TTrepwTOJv Slol to 

flTj TTTrjTLKol €LVaL Tr]V TWV 7TT€p(JL)V aV^7](JLV 61? TTjV 

rod hepjiaros TTaxvrrjra T^rpaixjilvrjv €XOVOlv. Slo 
10 /cat ovTOi fjLev ro) Kcirco ^X€(f)dpco fivovai,, Trept- 
arepal 8e /cat to, roiavra d/x^otv. ra 8e rerpairoha 
T(x)v choTOKOJV (fioXiScoTO, Igtiv TauTa 8e gkXtjpo- 
repa navra rpi^os, (joore /cat ra Sep/xara rod 
hipfxaros to ptev ovv irepl rrjV K€(f)aXr]v uKXrjpov 
ecjTLV avTolg, hioirep ovk e;^et ^Xecjyapov eKeWev, 
15 TO 8e KOLTcodev aapKcoSeg, coot' ^x^lv to ^Xed>apov 


^KapSapLVTTOvori S' ol ^apels opvides tovtw fiev 
ov. Tip 8' vpL€VL, 8ta TO ^paSelav elvai ttjv tovtov 
KLvrjoiv, SeXv 8e Ta)(elav yiveodai, 6 8* vpLrfv tolov- 
Tov. c/c 8e Tou Kavdov tov irapa tovs piVKTrjpa? 

20 OKaphapLVTTOVOlV , OTL ^eXtLOV aTT* O-PX^S puds TTjV 

(f)vaLV etvat avTwv, ovtol 8' exovGiv a.px'^v ttjv irpos 
TOV piVKTrjpa Trp6o-(f)vaLV' /cat to irpoadiov apx'rj tov 
nXayiov pidXXov. 

Ta 8e TeTpoLTToSa /cat cooTOKa ov OKapSapLVTTeL 
opLOLOjg, OTL ovh^ vypoLV avTols dvayKaZov e;^€tv /cat 


2o avay/catov, noppojOev yap rj XP^^*^^ t^? oi/jeajs. 8t6 
/cat Ta yapupwvvxci' p-^v o^vajTrd {dvojdev yap avTols 
7) Oeojpia TTJs Tpo(j)7Js, 8to /cat dvaTreTOVTai TavTa 
p-dXiUTa TCOV opvecov el? vifios), rd 8' eVtyeia /cat 
^07 TTTTjTLKdf olov dX^KTpvoves Kal rd ToiavTa, 


eyelid only. This is due to the hardness of the 
skin which surrounds the head, (a) The heavily 
built birds are not great fliers, and so the material 
which would have supplied growth for the wings has 
been diverted, resulting in thickness of the skin. 
These creatures, then, use only the bottom eyelid to 
cover the eye ; whereas pigeons and such use both 
eyelids. (6) With regard to the oviparous quad- 
rupeds : As the horny scales with which they are 
covered are in every case harder than hair, so their 
skin also is harder than ordinary skin. And as the 
skin on their heads is hard, they can have no upper 
eyelid ; but lower dovvn the skin has some flesh with 
it, and so they have a lower eyelid that is thin and 

Now the heavily built birds blink not with this 
lower eyelid, because its motion is slow, but A\ith 
the membrane above mentioned, whose motion is 
swift, as is requisite. This blinking or nictitating 
begins at the corner of the eye nearest the nostrils, 
because it is better that the membranes should have 
one place of origin rather than two, and in these birds 
this is where the eye and nostril are conjoined ; also, 
the front is more a place of origin than the side. 

The oviparous quadrupeds do not blink in this 
way, because, unlike birds, which have to use their 
eyes over great distances, they go upon the ground, 
and therefore there is no need for them to have 
fluid eyes or great accuracy of sight. The crook- 
taloned birds are sharp-sighted, for they view their 
prey from above, and that also explains why they 
fly to a greater height than other birds. The 
birds that remain on the ground, however, and do 
not fly much (e.g. barn-door fowls and the like) are 

185 - 


657b ^ ^ 

ovK o^vwnd- ovhev yap aura Kareireiyei rrpog 

rov ^Lov. 

30 Ot 8' IxOvc? Kal ra evro/ia /cat ra aKXr^poSepfj-a 
Siacfiepovra fiev e)(OvoL to, o/x/xara, ^X€(f)apov 8' 
ovSev avrwv ^)(^ei. ra f-iev yap GKXrjpoSepjJia oAco? 
OVK ex^i'' y] he rod f^Xecjidpov )(prjaLs Ta;!^erai' rrjv^ 
SepixarLKrjv e;^et ipyaauav aAA' dvrl rarjTqs rrj? 

35 (f)vXaKrjs TTOvra OKXripocfydaXpid icrrtv, oiov ^XeirovTa 
Sid rod ^Xec^dpov tt poGTTe(j)V kotos . inel 8' dvay- 
Koiov hid TTjv GKX-qpoTqra dp.pXvTepov pXeTretv, 

KLVOVfieVOVS i7TOL7](7€V Tj (f>VGiS TOV9 6(f)9aXlJiOVS TOL? 
658 a eVTOflOLS, Kal fJidXXoV €TL ToX? GKXrjpohepilOLS , CJGTTep 

kvia Tiov rerpaTTohajv rd cura, ottco? 6^-UT€pov ^Xerrrj 
GTpe(f)ovTa TTpos TO (j)djs Kol 8e;^o^£va Trjv avyqv. 
OL 8' l)(dv€s vyp6<^6aX}ioi fiev €lglv' dvayKaia ydp 

5 TOtS" TToXXriV TTOlOVpiivOLS KLVTjGLV Tj TT]S 6l/j€0JS €K 

TToXXov XPV^^S' Tolg fiev ovv Tret^oZ? 6 drjp ei)- 

hiOTTTOS' eK€iVOlS 8' €7761 TO vhojp TTpOS fJi€V TO O^V 

^AeVetv ivavTLOv, ovk ex^i he TroXXd ra TrpoGKpoiJG- 
jLtara npos ttjv oipLv oiGirep 6 drjp, hid fxev tout 
OVK ex^i ^Xe(j)apov {ovhev ydp rj (jiVGis rroiel fJLdrrjv), 
10 TTpos he T7]v TTaxvTTjTa Tov vhaTOS vyp6(f)6aXjJLOL 

XIV. J^Xecf)apihas 8' eTri tojv ^Xe(f)dpcov exovGiv 
OGa TpixoiS exovGiv, opviOes he Kal tcov (f)oXih(x>Td)v 
ovhev ov ydp exovGi Tpixas. rrepl ydp rod GTpov- 
6ov TOV Ai^vKov TTjv atTtW VGTepov epovpev tovto 

^ T17V Ogle : Kox vulg. : tt^v ante ipyaaiav vulg., om. SU. 

PARTS OF ANIMALS, II. xiii.-xiv. 

not sharp-sighted, since there is no urgent necessity 
for it in their kind of hfe. 

Many differences in the eye itself are found among 
the Fishes, the Insects and the hard-skinned Crus- 
tacea, thougli not one of them has eyeUds. In the 
hard-skinned Crustacea there cannot be an eyehd at 
all, for the action of an eyelid depends upon swift 
working of the skin. To compensate for the lack 
of this protection, all these creatures have hard 
eyes : it is as though the eyelid were all of a piece 
with the eyeball, and the creature looked through 
the lid as well. But since the vision is bound to be 
dimmed by this hardness of the eye, Nature has 
given the Insects (and even more noticeably the 
Crustacea) movable eyes, just as she has given some 
quadrupeds movable ears ; this is to enable them 
to turn towards the light and catch its rays and so 
to quicken their vision. Fish have fluid eyes for the 
following reason. They move about a good deal and 
have to use their sight over long distances. Now 
when land-animals do this, they are looking through 
air, which is highly transparent ; but fish move about 
in water, which is inimical to sharpness of vision ; so 
to counteract its opacity their eyes are fluid in 
composition. At the same time, water contains far 
fewer objects to strike against the eyes than the air 
does ; hence fish need no eyelids, and because 
Nature never makes anything without a purpose, 
they have none. 

XIV. Those animals that have hair on their body Eyelashes 
have eyelashes on their eyelids : the others (birds ^°*^ ^*^" 
and the creatures with horny scales) have none. 
There is one exception to this rule : the Libyan 
ostrich, which has eyelashes. The cause of this 

G 187 


658a ^ ^ 

15 yap e)(€L jSAe<^aptSa? to i,wov. /cat tojv ixovrojv 
Tpt^as" eV* dfX(f)6Tepa ol dvdpcoTTOi fxovov exovcnv. 
rd ydp rerpdnoSa tojv t,a)OJV iv rols vtttlols ovk 
€X€L TpLXCL?, aAA' iv TOt? TTpaveGL fiaXXov ol 8* 
dvdpojrroi rovvavTiov iv rots vtttlol? fxaXXov rj iv 
rois TTpaviuLV. GKeTrrj^ yap X^P^^ ^^ Tpix^S vtt- 
dpxovGL TOtg exovGLV rot? fJiev ovv Terpdrroai rd 

20 TTpavrj SelraL fidXXov rrjg crKeTTrjg, rd Se Trpoadia 
TLfJLLwrepa jjiiv, dXXd Aect^et Sid rr)v Kafjupiv rols 
S' dvdpcijTTOis inel i^ luov hid rrjv opdorrjTa rd 
TTpoodia rols OTTiaOioLS, rols nfMLCorepoig vrriypaxpev 
Tj (f}VGLS rrjv ^OTjOetav del ydp iK rG)v ivSexo- 
ixivojv alrla rod ^eXriovos iartv. /cat Std rovro 

25 rajv rerpaTToScov ovOkv ovre ^Xet^apiSa e;^et rrjv 
Karcodev, aAA' vtto rovro ro ^Xicfyapov iviois rrapa- 
(f)Vovrai fiaval rpix^s, ovr iv rals /xaap^aAats" ovr 
inl rrj? rj^T^S, wcrTrep rols dvOpcoTTOLS' aAA' avrt 
rovrojv rd fiev Kad^ dXov ro crco/xa TTpaves^ 8eSa- 
crvvrai rals dpi^lv, otov ro rcov kvvcov yevos, rd 8e 

80 Xo(f)Ldv ex^L, Kaddirep lttttol /cat rd roiavra rcov 
^cpcov, rd 8e ;)^atT7]v, cooTrep 6 apprfv Xeojv. ert 8' 
oua KepKovs ex^t jjltjkos ixovaas, /cat ravras CTrt- 
KeKOGfirjKev rj (fivcns Opi^i, rols p-ev puKpov exovau 
rov oroXov paKpals, (Zonep rols Ittttols, rols 8e 

35 jiaKpov j3pax€LaLs, /cat /cara rrjv rov dXXov acop-aros 

cf)V(TLV' TTavraxov ydp aTroStSwcrt Xaftovaa ireptodev 

TTpos dXXo pLopiov. oGOis 8e ro ocopa Saav Xiav 

658 b 7T€7TOLr]K6, rovroLs ivheojs e;\;€t rd rrepl r7]v KepKov^ 

otov €771 rdJv dpKrcov avp,^e^rjK€V, 

^ Tipavks delet Piatt. 


will be explained later. '^ Man is the only animal 
which has eyelashes on both lids. Why is this ? 
The quadrupeds tend to have more hair on their 
backs than on the underside of the body ; but in 
man the reverse is true. The purpose of hair is to 
give protection ; and as the quadrupeds go on all 
fours, they need more protection on their backs ; so 
they have no hair on their front, although the front 
is the nobler of the two sides. Man goes upright, 
and so there is nothing to choose as regards his need 
of protection between front and back. Therefore 
Nature has prescribed the protection for the nobler 
side, the front — an example of how, out of given 
conditions, she is always the cause of that which is 
the better. This, then, is why none of the quad- 
rupeds has lower eyelashes (though some have a 
few scattered hairs growing on the lower eyelid), 
or hair in the axillae or on the pubes, as man has. 
Instead of this, some of them have thick hair all 
over the back part of ^ their body {e.g. dogs), some 
of them have a mane {e.g. horses and such), others 
a flowing mane, like the male lion. Again, if an 
animal has a tail of any length. Nature decks that 
with hair too ; long hair for tails with a short stem 
{e.g. horses), short hair for tails Mith a long stem. 
This, however, is not independent of the general 
condition of the whole animal, for Nature gives 
something to one part of the body only after she 
has taken it from another part. So when she has 
made an animal's body extremely hairy, we find 
that there is not much hair about the tail. An 
example of this is the Bears. 

« See 697 b 13 ff. 
* Piatt deletes " the back part of." 



658 b 

Trjv he K€(f)aXr]v avdpcoTTOS eon rwv ^cocov Sacrv- 

rarov, i^ dvayKT]? (xev 8ta rrjv vypor-qra rod 

eyK€(f)dXov Kal Sta rds pacj^ds (ottov yap vypov /cat 

6 depfxov TrXelaTOV, eVrau^' dvayKolov 7tX€lgt7]v elvat 

rrjV €K(f)VGLv), €V€K€V Se ^OTjdeLa?, OTTCOS GK€7Td^CO(7L 

<j)vXdTrovGai rds VTrep^oXds rod re ipv^ovs Kal ri^s 
dXeas. TrXeiGTOs S' cov Kal vyporaros 6 ra)v 
dvdpcoTTCOV iyK€cf)aXos TrXeioTris Kal rrj? ^vXaKTjS 
heir ai' ro yap vyporarov Kal ^et Kal xfj-ux^raL 

10 fidXicrra, to S' eVavrioj? ^xov aTTaOearepov ioriv. 
'AAAo. 7T€pl ixkv TOVTCov TTapeK^rjvaL GVjJL^e^T^KeV 
ixofJLevois T7J9 TTcpl rds ^Xe(j)apihas atVta?, 8td ttjv 
ovyyeveiav avraJv, cucrre nepl rcov Xolttcov iv rols 
OLKeloL? Kaipols aTTohoreov rrjv fiveiav. 

XV. At 8' 6(f)pv€? Kal at ^XecfiaplSes dpi^orepai 

15 ^orjOelas X^P'-^ €lglv, at /xev o^pves rwv Kara- 
paLvovTOJv vypojv, ottojs aTTOGreycoGiv olov drroyei- 
crcujLta Tcor drro rrjg Ke(f>aXrjg vypajv, at Se /3Ae</)apt8€S 
rcbv TTpo? rd ofxjJLara ttpogttltttovtcjv eVe/cev, olov 
rd p^apa/ccojLtara ttolovgl rives Trpo rcov epyfidrajv} 
elal 8* at [xev 6(f)pves errl Gwdeoei oorcov, 8to Kal 

20 SaCTUvovrat TroAAotS" dTToyrjpdaKovoLV ovtcjjs ojore 
SelaOat Kovpds' at he ^Xe(j)apihes eTrl Trepan 
<f)Xe^LOJV, fj yap to Seppua Trepaivei, Kal rd (j)Xe^ia 

^ epyfioLTcov scrips! : epyfxdTCJv Bekker : ipvudrcov ed itores. 

« This is one of the passages fastened upon by Bacon in 
his tirade against the importation of final causes into physics, 
Adv. of Learning (publ. 1605), ii. pp. 29, 30 : " This I finde 
done not onely by Plato, who euer ancrcth vppon that shoare, 
but by Aristotle, Galen, and others, who do vsually hkewise 
fall vppon these flatts of discoursing causes ; For to say that 
the haires of the Eye-liddes are for a quic-sette and fence about 



Man has the hairiest head of all the animals. This 
is (a) due to necessity, because the brain is fluid, and 
the skull has many sutures ; and a large outgrowth 
necessarily occurs where there is a large amount of 
fluid and hot substance. But also (6) it is on purpose 
to give protection ; that is, the hair affords shelter 
both from excessive cold and from excessive heat. 
The human brain is the biorsrest and the most fluid 
of all brains ; therefore it needs the greatest amount 
of protection. A very fluid thing is very liable both 
to violent heating and \dolent cooling, while sub- 
stances of an opposite nature are less liable to such 

This, however, is a digression. We were led into it 
because the subject was connected with our investi- 
gation of the cause of eyelashes. Anything further 
that there is to be said about it will be said in its 
proper place. 

XV\ Both eyebrows and eyelashes exist to afford 
protection to the eyes : the eyebrows, like the eaves 
of a house, are to protect the eyes from the fluids 
that run down from the head ; the eyelashes are Uke 
the palisades which are sometimes put up in front of 
an enclosure ; their purpose is to keep out things that 
try to get in." However, the eyebrows are placed 
where two bones join (which is why they often get so 
thick in old age that they have to be cut) ; and the eye- 
lashes are placed at the ends of small blood-vessels, 
which have to stop where the skin itself comes to 

the Sight . . . and the like, is well inquired & collected in 
Metaphisicke, but in Phisicke they are impertinent." But 
there is no incompatibility, p. 33, " For the cause rendred 
that the haires about the Eye-liddes are for the safeguard of the 
sight, doth not impugne the cause rendred, that Pilositie is 
incident to Orifices of Moisture.'" See also Xen. Mem. i. 4. 6. 



658b ^ ^ ^ / r/ , , 

TTepas €X€i rod iJ,y]Kov£- coctt' dvayKolov Sta ttjv 

OLTTLovaav LKfJidSa acofjLartKrjv ovaav, dv fi'q ri rrjs 

(f)V(T€a>? epyov eixTTohior^ irpos aXkriv •)(prJGLV, Koi 

25 hid TTjv Toiavrriv atTiav ef dpdyKTjs iv rots roTTOt? 
TOUTot? yiveoOai rpixo-s. 

XVI. Tot? piev ovv aAAoi? ^cools toTs rerpdrrooi 
/cat ^cporoKOLS ov TToppw rpoTTOV TLvd SiearrjKev 
dXX-qXcov TO rrjs OGcfyp-^aecos aloO-qT-qpLOv, aAA' daa 

30 fxev ex^L 7TpopLr]K€LS et's" orevdv d7rrjyp.€vas ra? 
GLayovas, ev rw KoXovpLevo) pvyx'^^ Kal ro rcbv 
pLVKTiqpojv ivvTTdpx^L piopiov /caret rov ivSexop-cvov 
rpoTTOv, roZs S' aAAot? /xaAAov SLrjpOpcopevov earl 
TTpos rds Giayovas. 6 8' eAe</)as' IhiairaTov e;\;et 
Tovro TO pLopiov Tcbv dXXcov i,a)Cov TO re ydp 

35 pLeyeOos /cat rrjv SvvapiLv e;^et TrepLrrrjv. pLVKrrjp 
ydp iuTLV (L TTjv Tpo(f)rjv TTpoadyerai, Kaddrrep X^^P^ 
€59 a ;)^ptu/xevos', rrpos to GTopLa, t7]v re ir]pdv /cat tt^p' 
vypdvy /cat to, SevSpa TT^pLeXiTTajv dvaGTra, /cat 
XprJTai Kaddrrep dv el X^^P^- '''V^ 7^9 '/"^crtv eAajSe? 
a/xa TO ^ojov eVrt /cat 7Tet,6vy coctt* eVet tt^v Tpo(j)'y]v 
i^ vypov Gvve^aivev e;^etv, dvaTTvetv 8* dvay/catov 
6 Tre^ov ov /cat evatpLov, /cat /xi^ ra^^etav Troteta^at tt)^ 
pL€TaPoXr]v e/c tou vypov TTpos to ^r]p6v, Kaddrrep 
eVta Ttov l^cpoTOKOJV /cat ivalpajv /cat dvaTTveovTcov, 
TO ydp pLeyedos ov virep^dXXov, dvayKoiov opLoicos 
rjv XPV^^^^ '^'^ vypcp ojonep /cat Tif^ y^. otov ouv 
rot? KoXvpL^rjTOLS evioi irpos ttjv dvanvorjv Spy ava 

10 TTopi^ovTai, Lva TToXvv xpoi^ov ^^ "^fj OaXdTTT) jLte- 
vovt€£ eXkcoglv e^ojdev tov vypov Stct tov dpydvov 
Tov depa, tolovtov tj (f)VGLg to tov pLVKTrjpos pL€- 
yedos €7T0LrjG€ toIs iXe^aGiv. hiorrep dvarrveovGLV 

• Or " strength." 


an end. Thus, owing to the fact that the moisture 
which comes off is corporeal in composition, hair must 
be formed at these places even on account of a neces- 
sary cause such as this, unless some function of Nature 
impedes by diverting the moisture to another use. 

XVI. The general run of viviparous quadrupeds Nostriia. 
differ very little among themselves as regards the 
organ of smell. The following variations occur, how- 
ever. Those animals whose jaws project forward and 
become gradually narrower, forming what is called 
a snout, have the organ of smell in their snout — this 
being the only possibility ; in the others, the jaws 
and nostrils are more definitely separated. The 
elephant's nose is unique owing to its enormous size 
and its extraordinary character. '^ By means of his 
nose, as if it were a hand, the elephant conveys 
his food, both solid and fluid, to his mouth ; by 
means of it he tears up trees, by winding it round 
them. In fact, he uses it for all purposes as if it 
were a hand. This is because the elephant has a 
double character : he is a land-animal, but he also 
lives in swamps. He has to get his food from the 
water ; yet he has to breathe, because he is a land- 
animal and has blood ; owing to his enormous size, 
however, he cannot transfer himself quickly from the 
water on to the land, as do quite a number of blooded 
viviparous animals that breathe ; hence he has to be 
equally at home on land and in the water. Some 
divers, when they go down into the sea, provide 
themselves with a breathing-machine, by means of 
which they can inhale the air from above the surface 
while they remain for a long time in the water. 
Nature has provided the elephant with something of 
this sort by giving him a long nose. If ever the 



659 a ^ 

dpavres o-vco Sta rod vharos rov fxvKrrjpa, dv nore 
TTOLCJvrai hi vypou rrjv nope lav Kaddrrep yap 

15 elTTOfxev, pvKTijp ianv 77 Trpo^ooKls rols e'Ae^acrtv. 
€7761 S' d'^vvarov rjv elvai rov jjLVKrrjpa tolovtov p^rj 
fxaXaKov ovra p.7]Se KdpLnreaOaL Svvdpcvov (eveiro- 
hit^e yap dv rw [X'qKei Trpog to Xa^elv ttjv dvpadev 
rpocfyijv, KaOdrrep cpaal rd Kepara rols OTTiodovopiois 

20 ^ovoiv Kal ydp eKeivovs vep^eadai (fyaoLV vtto- 
■)^iDpovvras TTaXijiTTvyrihov) — vrrdp^avros ovv tolov- 
tov Tov pLVKTTipos, T] ^VGis TTapaKaTaxprjrai, KaO- 
aTTep €LCjodeVj €7tI TrXeiova tols avTols popioiSi dvTl 
TTJs Tcov TTpoaOiojv 7Tohcx)v xp^^OL^' TOVTOVs ydp ra 

TToXvhdKTvXa TCOV TeTpaTTohoJV dvTl X^^pd>^ €X0VGIV, 

25 aAA* ov p.6vov €vex VTTooTdoecjJs tov ^dpovs' ol S' 
iX€(f)avT€s TCOV TToXvSaKTvXcxJv eloL, Kal ovT€ Sixd- 
Xovs exovGLV ovT€ pcovvxo^S TOV? TToSas' iirel 8e to 
fieyedos ttoXv /cat to ^dpo<; to tov crc6/xaTOS", Sta 
TOVTO piovov ipeiopiaTos etcrt x^P^'^> '^^^ ^^^ ^W 
PpaSvTTJTa Kal ttjv d(f)vtav ttj? Kdpipecos ov XPV' 

UipLOL^ TTpOS dXXo OvOlv. 

so Ata /xev ovv ttjv dvanvorjv e;^et pLVKTrjpa, Kaddnep 
Kal TCOV dXXojv €Ka(jTOv Twv ixovTcov nXevpova 
t^axDV, Sta Se Tr]v iv tw vypco hiaTpi^riv Kal ttjv 
ppaSvTTJTa TTJs CKeWev pLeTa^oXi]? Swdpievov iXiT- 
T€odai Kal piaKpov d(f)'r]p7]p€V7]? Se ttjs toov ttoScov 

85 XPV^^^^Sy ^Ctt Tj (j)VGLS, d)G7T€p €L7T0pL€V, KaTaXp'r]TaL 

Kal TTpos TTjv dno TCOV TToSojv yLvopL€vr]v dv po-qdeiav 

TOVTO) TO) pLOpiLp, 

659 b Ot S' opviBes Kal ol 6(f)€is Kal oGa d'AA' eVat/xa 
* XpT^oLixoi Rackham : p^pT^ai/iov vulg. 


elephant has to make his way through deep water, 
he will put his trunk up to the surface and breathe 
through it. This is possible, because, as I have said 
already, the trunk is really a nostril. Now it would 
have been impossible for the nostril to be put to all 
these uses if it had not been soft and able to bend ; 
for then by its very length it would have prevented 
the animal from getting its food, just as they say the 
horns of the " backward-grazing " oxen do, forcing 
them to walk backwards as they feed.^ So the trunk 
is soft and pliable ; and in consequence Nature, as 
usual, takes advantage of this to make it discharge 
an extra function beside its original one : it has to 
serve instead of forefeet. Now in polydactylous 
quadrupeds the forefeet are there to serve as hands, 
not merely in order to support the weight of the 
animal ; but elephants (which must be included under 
this class of animals, because they have neither a 
solid hoof nor a cloven one) are so large and so heavy 
that their forefeet can serve only as supports ; and 
indeed they are no good for anything else because 
they move so slowly and are quite unsuited for 

So the elephant's nostril is there, in the first place, 
to enable him to breathe (as in all animals that have 
a lung) ; and also it is lengthened and able to coil 
itself round things because the elephant spends 
much of his time in the water and cannot quickly 
emerge upon land. And as his forefeet are not 
available for the normal function, Nature, as we 
said, presses the trunk into service to supply what 
should have been forthcoming from the feet. 

The Birds and Serpents and the quadrupeds which 

*» See above, on 6-A8 a 16. This is from Herodotus, iv. 183. 
g2 195- 


659 b 


€)(ovai Tcov iivKT-qpojv TTpo rod GToyiaros, cucrre O 
elireXv jjLVKrrjpas, el fir] Sua to epyov, ovk cxovgl 
^avepa)s hnqpOpcopLevovs' aAA* tj y opvig wore 
5 firjOev av eiTreZv ex^t^ plvas. rovro he GvpL^e^rjKev, 
on avTt oLayovojv e^ei to KaXovpievov pvyxos- alricL 

8e TOUT60V Tj (j)VGL£ 7) TCOV OpviQoJV GVVeGT7]Kvla 

TOVTOV Tov rpoTTov. hiTTOVv ydp eGTL /cat rrrepv- 
yojTov, oiGT dvdyKrj puKpov to ^dpos ^x^iv to tou 
avx^vos Kal to tt]? KecfyaXrjs, cjG-nep Kal to GrrjOos 

10 Grevov ottcos l-iev ovv fj ;^pT^o-t/xov npog re rrjv 
dXKTjV Kal Sid T'qv Tpo(f)TJv, ooTtuSe? exovGi ro 
pvyxos, GTEVov Se Sid ttjv fJUKpoTrjra rrjs K€(f)aXrjS. 
iv 8e TO) pvyx^L tovs rropovs exovGL rrjs OG^priGecuSt 
fjLVKTTJpas S' ^x^LV dSvvarov. 

Ilepl 8e Tojv dXXcov ^cocov rwv fXTj dvarTveovrcov 

16 etpTjrai, irporepov hi rjv alriav ovk exovGL p,v- 
KTrjpaSy aXXd rd pi€v 8ta rcjv ^payxicov, rd 8e 8ta 
rov avXov, rd 8* ivrofxa Sid rov vTro^wfiaro? 
aloddvovrai tcjv ogijlojv, Kal iravra rep GV[i(j)VTCp 
7Tvevp.aTL rev GojjJiaros (prrep^ (K.aX)*' Kivelrai' rovro 
8* VTrapx^t, (l)VG€L TTaGi Kal ov dvpaOev eireiGaKrov 


20 'Ytt-o 8e Tous" fJLVKTTJpas T] rwv ;)^etAcov eo"Tt (f)VGLS 
rots exovGL rojv evaipLOJV ohovras. roXs yap opvcGi, 
KaOdnep eiTTopiev, hid rrjV rpO(f)rjv Kal rrjv dXKTjv ro 
pvyxos oGrcJobes eonv GVviJKrai ydp €ls eu avr 
ohovrcxjv Kal ;)^etAajp', wG-rrep av et Tt? a^eAtuv 

25 dvdpcjTTov rd x^^^V '^^^ ou/x^uoa? tous" dvcodev 

^ ojOTOKa Z, vul^. : ^woroKa EPSUY. 
* €X€i S : ix^iv vulg. 



like them are blooded and oviparous, have their 
nostril-passages in front of the mouth : but they have 
nothing which except for its function can be called 
nostrils — nothing distinctly articulated. A bird, at 
any rate, one might say has no nose at all. The 
reason for this is that its beak really replaces jaws. 
And this is because of the natural structure of birds. 
A bird is a winged biped ; hence its head and its neck 
must be light in weight, and its breast must be 
narrow ; and it has a beak, which (a) is made out of 
bony material, so that it will serve as a weapon as 
well as for the uptake of food, and (h) is narrow, owing 
to the small size of the head. It has the passages for 
smell in this beak, but it is impossible for it to have 
nostrils there. 

We have spoken already about the animals that do 
not breathe, and shown why they have no nostrils : 
some of them smell by means of the gills, some 
through a blow-hole ; while the insects smell through 
the middle part of the body. All of them smell, as 
all of them move, by means of the connate pneuma ° 
of their bodies, which is not introduced from without, 
but is present in all of them by nature. 

In all blooded animals that have teeth, the lips have Lipa. 
their place below the nostrils. (As stated already, 
birds have a bony beak for getting food and for de- 
fence ; and this is as it were teeth and lips run into 
one. The nature of the beak can be illustrated thus. 
Supposing, in a human being, that the lips were 
removed, and all the upper teeth were welded to- 

" Cf. De somno et vig. 455 b 34 fF. For a full account of 
'Lvfi<f)irrov YLveufia see G.A. (Loeb edn.), pp. 576 ff. 

' coTTcp SUZ^ : coanep vulg'. • <Kal> Peck. 



659b ^ ^ 

ohovrag ;^copt? /cat rovg Kariodev TTpoaydyot [XT]ko9 

TTOirjaas ajJicfyoTepcjodev ets" arevov et-q yap dv rovro 

tJSt] pvy^os opvidojhes. roZs jxev ovv aAAot? ^cLois 

TTpOS GCUTl^plaV TCJV oSoVTCJV 7) TtUV ;)^etAcDy (f)V(TiS 

iuTL Kal rrpos <f>vXaKr]Vy hioirep ojs eVetVcov /Lter- 

80 exovGL rod aKpi^o)^ Kal KaXojs r) rovvavriov, ovrco 

Kal Tov SirjpdpaxjOaL rovro ro pLopiov exovuiv ol 8* 

avdpoQTTOi /xaAa/ca Kal oapKOjhr] Kal SvvdjJLeva X^P^~ 

^eoOat, (f)vXaKr]s 9^ eVe/ca rwv ohovrcov warrep Kal 

rd d'AAa, Kal fxaXXov en Sta to €V' Trpos yd.p ro 

XpTjod ai ro) Xoycp Kal ravra. woirep yap r7]v 

35 yXcjrrav ovx oyLoiav rots aAAots" eTroLTjaev r] <^vols, 

TTpos ipyaoias hvo KaraxprjcroLfJievY] , KadaTrep 

660 a etTTOjLtev TTOLelv avrrjv inl ttoXXcov, rr^v [xev yXdJrrav 

rctjv re ;)(U/xa)V €V€K€V Kal rod Xoyov, rd he x^^^V 

Tovrov 6^ eve/cev /cat rijs rojv oSovrcov (fyvXaKTJ?. 6 

fxev ydp Xoyos 6 Std rrjg (fjojvijg e/c rojv ypa[Xfxdrwv 

GvyKeiraL, rrj? Se yXojrr-qs fJirj roiavriqs ova-qs [JLy]he 

5 ra)V x^^Xcjv vypojv ovk dv rjv (^Oeyyeadai rd TrXeiora 

rojv ypa[jifidrajv rd fiev ydp rrjs yXcorrr]? elal 

TTpoo^oXaiy rd he ovpi^oXal rcov ;\;€tAajv. rroias Se 

ravra Kal TTouag Kal rivas ex^L hiacjiopds. Set 

TTwddveodai irapd rcov [xerpiKcov. 

^AvdyKT) 8* -qv evdvs aKoXovOrjaai rovrcov rcov 
10 fiopLcov eKarepov Trpds rrjv elpiqpLevriv XP^^^^ evepyd 
Kal roLavrrjv exovra r-qv (j>vGiv hid odpKiva. fjia- 
XaKcordrrj S' t] adp^ r) rcov dvdpcoTTCOV v7Trjpx€v. 
rovro Se 8ta to alaOrjrLKcorarov elvat rcov ^ojcov 
rr]v hid rrjs d(l)fjs aLuOrjcnv. 



gether, and similarly all the bottom teeth, and then 
each set were extended in a forward direction, and 
made to taper : this would result in a beak such as 
birds have.) In all animals except man the lips are 
intended to preserve and to protect the teeth ; hence 
we find that the distinctness of formation in the lips 
is directly proportionate to the nicety and exactitude 
of formation in the teeth. In man the hps are soft 
and fleshy and can be separated. Their purpose is 
(as in other animals) to protect the teeth ; but — 
still more important — they subserve a good pur- 
pose, inasmuch as they are among the parts that 
make speech possible. This double function of the 
human lips, to facilitate speech as well as to protect 
the teeth, may be compared with that of the human 
tongue, which is unlike that of any other animal, and 
is used by Nature for two functions (a device of hers 
which we have often noted), {a) to perceive the 
various tastes, and (h) to be the means of speech. 
Now vocal speech consists of combinations of the 
various letters or sounds, some of which are produced 
by an impact of the tongue, others by closing the lips ; 
and if the lips were not supple, or if the tongue were 
other than it is, the greater part of these could not 
possibly be pronounced. For further particulars 
about the various differences between these sounds 
you must consult the authorities on Metre. 

It was wece^^ar?/, however, from the start that each of 
these two parts should be adapted and well-fitted for 
their function as stated above ; therefore their nature 
had to be suitable thereto, and that is why they are 
made of flesh. Human flesh is the softest kind of flesh 
there is ; and this is because man's sense of touch is 
much more dehcate than that of any other creature. 



660 a 

XVII. 'Ytto 8e Tov ovpavov ev rep aropLari 17 

15 yXayrra rols Repots icrrl, rolg fxev tte^oIs ct^^Sov 
ojiOLCOs Trdai, rot? S* aXkois avoyiOLOJs koL avrols 
Trpog aura /cat 77/36? ra Tre^a rcov t^ojojv. 6 [M€V ovv 
avBpwTTos dTToXeXvfJuevrjv re jLtaAtara ttjv yXcorrav 
/cat TrXarelav /cat /xaAa/ccurarr^v ^X^''*^ ottojs Trpos 
api(j)oripas rj ras ipyaoias xPV^''l^oSy vpos re rrjv 

20 Tcjv x^H-^^ aiodiqoLV (o yap dvdpcoTTOs evaLCidrjro- 
raros raJv aAAcov t^cpojv, /cat 77 jjLaXaKrj yXcorra 
(^aLaOrjTLKajrdrrjy' dTrrLKOjrdrT] ydp, r) Se yeucjts" etc/)!] 
Tts" eVrtv), /cat Txpos" tt^v tcov' ypafjLjJLdrajv hidpdpujaiv 
/cat 77p6s" Toy Aoyov 7] piaXaKT] /cat TrAareta XP'?" 
oipios' ovareXX^Lv ydp /cat npo^dXXeLV TravrohaTTrj 

25 TOLavrr] ovoa /cat dTToXeXvfxevT] pidXior dv SvvaiTo. 
Sr)XoL 8' ocrots" /at) Atav aTToAeAuraf t/jeXXi^ovrai 
ydp /cat TpavXi^ovGL, rovro 8' ecrrtv evScia rcDv 

"Ev T€ TOJ TrAaretav etvat /cat to cttcvtJv ecrrtv 
ev yap to) fieydXco /cat to yuKpov, iv 8e tw fiLKpa) 
TO jLteya ot)/c eariv. 8t6 /cat tcov opviOcov ol ixdXiora 

80 <l)d€yy6fJievoL ypdyipbara irXarvyXajTrorepoi rwv dX- 
Aa>v €t(7tV. to, 8* evaifxa /cat t^cooroKa rcov Terpa- 
TToBoJv jSpa^etav tt^s" (Jxjjvtjs e^ct SidpOpcoGLV 
GKXrjpdv T€ ydp /cat ou/c dTToXeXvfievrjv exovGi 
/cat Trax^tav tt^v yAa/TTav. tcov 8' opvldcov eVtot 
7ToXv(j)(x>voLy /cat TrXarvrepav ol yajJUpcovvxoL exovaiv. 

85 7ToXv(j)(JJVOl 8' Ot fJLLKpOTepOL. /Cat Xpd^'^'^^'' '^fj 

yXwrrrj /cat 77^6? epfirjvetav dAAT^Aots" Trdvres pi^v, 
660 b erepoL Se tcDv crepcov i^aXXov, aJoT* ctt* ivlcov /cat 

^ /cai /LiaA. €^€1 post re Vlilg. ; traiisposui. 
^ aladrjTiKCJTaTr) supplevi. 


XVII. Under the vaulted roof of the mouth is Tongu©. 
placed the tongue, and it is practically the same in 
all land-animals ; but there are variations in the other 
groups, whose tongues are as a whole different from 
those of land-animals and also different among them- 
selves. The human tongue is the freest, the broadest, 
and the softest of all : this is to enable it to fulfil 
both its functions. On the one hand, it has to per- 
ceive all the various tastes, for man has the most 
delicate senses of all the animals, and a soft tongue 
is the most sensitive, because it is the most re- 
sponsive to touch, and taste is a sort of touch. It 
has, also, to articulate the various sounds and to 
produce speech, and for this a tongue which is soft 
and broad is admirably suited, because it can roll 
back and dart forward in all directions ; and herein 
too its freedom and looseness assists it. This is 
shown by the case of those whose tongues are slightly 
tied : their speech is indistinct and lisping, which 
is due to the fact that they cannot produce all the 

A tongue which is broad can also become narrow, 
on the principle that the great includes the small, 
but not vice versa. That is why the clearest 
talkers, even among birds, are those which have ^ 
the broadest tongues. On the other hand, the 
blooded viviparous quadrupeds have a limited vocal 
articulation ; it is because their tongues are hard 
and thick and not sufficiently loose. Some birds — 
the smaller sorts — have a large variety of notes. 
The crook-taloned birds have fairly broad tongues. 
All birds use their tongues as a means of communica- 
tion with other birds, and some to a very consider- 
able extent, so much so that it is probable that in 



66D b 

fiddrjCLV etvai Sok€lv nap' aXXriXojv eipr]rai 8e Trepl 

avrcjv iv rats laropiais rat? Tre/ot rwv S^cocov. 

Tcov 8e 77€^cDv Kal cootokcov Kal ivaipLWV npos 

/lev T17V T7]? cf)a)vrjs ipyaulav dxp'r]crrov ra ttoXXol 

6 TTjv yXojrrav e;^€t /cat TrpoaheSepLev-qv Kal OKXrjpdv, 

rrpos Se tt^v twv ■^^vjjlojv yevatv oi r' 6(f)eis Kal ol 

aavpoi fjLaKpdv Kal hiKpoav exovcnv, ol jjl€V ocjyeis 

ovTCD jxaKpav ojgt e/creiVecr^at e/c fiiKpov inl ttoXv, 

hiKpoav he Kal to aKpov XeTrrov Kal rptp^coSe? hia 

rr]v Xi)(y€Lav tt^s (f)iJGecos' hiTrXrjv yap rrjv rjhovrjv 

10 Krarai tojv x^H-^^y wanep hLTrXrjv exovra ttjv rrjs 
yevaeoj? aiodrjuLV. 

*'E;^et he Kal ra (jlt] eVat/xa rcov t^coajv to alody)' 
TLKov raav x^l^^^' p-opiov Kal ra eVat/xa iravra' Kal 
yap 60a fJLT) hoKel rols ttoXXoXs e;^etv, otov evioL rcjv 
ixOviov, Kal ovTOL rpoirov riva yXlaxpov exovon, Kal 

15 GX^hov TTapaTrXrjaLOjg roXs TTorapLLois KpoKohelXotg. 
Ol) (^atVovrat S' 01 TrXelGTOi avrojv exetv hid tlv* 
alriav evXoyov dKavdcohr]^ re ydp eVrtv o ro-rrog 
rod orofiaros Trdoi rols roiovrois, Kal hia ro 
fjLLKpov xpovov etvai rr]v alod-qaiv rols evvhpoLs rwv 
XVjJLCOV, wGTrep Kal rj ;^p7Jcrt? avrrjs ^paxela, ovrcx) 

20 jSpa^^etav exovGiv avrrjs Kal rrjv hidpOpcuGiv. raxela 
S' T) hlohos els TTjv KoiXiav hid ro fir] oiov r eivai 
hiarpi^eiv eKx^piit^ovras' TrapeinriTrroL ydp dv ro 
vhctjp. ojGr edv jjirj ris ro Grofxa eiriKXivr], firj 
(f>aiveGdai dc^eGrrjKos rovro ro piopiov, aKavOcohrjs 
8' iarlv ovros 6 r ottos ' GvyKeirai ydp €/c rrjs 

25 Gvpn/javGecjDS Tcbv ^payx^coVy (Lv rj (f)VGis aKavdcohrjs 

" See Hist. An. 504 b 1, 536 a 20 ff., 597 b 26, 608 a 17. 


some cases information is actually conveyed from one 
bird to another. I have spoken of these in the 
Researches upon Animals.^ 

The tongue is useless for the purpose of speech in 
most of the oviparous and blooded land-animals be- 
cause it is fastened down and is hard ; but it is very 
useful for the purpose of taste, e.g. in the serpents and 
lizards, which have long, forked tongues. Serpents' 
tongues are very long, but can be rolled into a small 
compass and then extended to a great distance ; they 
are also forked, and the tips of them are fine and hairy, 
owing to their having such inordinate appetites ; by 
this means the serpents get a double pleasure out 
of what they taste, o\ving to their possessing as it 
were a double organ for this sense. 

Even some of the bloodless animals have an organ 
for perceiving tastes ; and of course all the blooded 
animals have one, including those which most people 
would say had not, e.g., certain of the fishes, which 
have a paltry sort of tongue, very like what the river- 
crocodiles have. Most of these creatures look as if 
they had no tongue, and there is good reason for this. 

(1) All animals of this sort have spinous mouths ; 

(2) the time which water-animals have for perceiv- 
ing tastes is short ; hence, since the use of this 
sense is short, so is the articulation of its organ. 
The reason why their food passes very quickly into 
the stomach is because they cannot spend much time 
sucking out its juices, otherwise the water would get 
in as well. So unless you pull the mouth well open, 
you will not be able to see that the tongue is a sepa- 
rate projection. The inside of the mouth is spinous, 
because it is formed by the juxtaposition of the gills 
which are of a spinous nature. 



630b ^ ^ , , , , X 

Tot? Se KpoKoSeiXots uvfi^aXXeral tl Trpos Tqv 

rod fjiopiov TOVTOV avaTrrjpiav koi to rrjv oiayova 

TTjv KOLTaj OLKLvqTov e;^€tv. €GTL jJL€V yap -q yXaJrra 

TTJ KOLTaj GviJi(j)vr]s, ol 8' exovGLV cooTTep avdiraXiv 

TTjV dvCO KOLTOJ' TOls yap aAAot? "J] civOJ dKLVrjTOS. 

30 Trpog [lev ovv rfj dvoj ovk exovGL rr^v yXcarrav, on 
evavTiOJS dv e^oi irpos rrjV rrj? rpo(f)rjs €lgoSov, upos 
he rfj Kara), on coGrrep fieraKeLfievT] rj dvoj ecrrtV. 
en he Kal Gvpi^e^rjKev avrco 7Tel,cp ovn l^rjv IxOvojv 
^Lov, wGre Kal hid rovro dvayKatov dhidpdpoirov 
avrdv ex^iv rovro rd fiopiov. 

35 Tdv 8' ovpavov GapKcohrj 77oAAot Kal rdJv IxQvojv 
exovGL, Kal rcjjv TTorajiiojv evioi G(j)6hpa GapKwhr] 
Kal fiaXaKov, olov ol KaXovfievoL Kvrrplvoi, cjGre 
661 a hoKelv roLS pur] gkottovglv aKpi^ajs yXwrrav ex^t,v 
ravrrjv. ol 8' IxOves hid rrjv elp'qpievqv alriav 
exovGi pLev ov Gacf)rj 8' exovGL rrjv hidpdpojGLV rrjs 
yXcvrrrjs. eirel he {rrjS rpo^r^s x^P^^^^ ^<^^ '^^^ 
6 p^ujLtcuv aiGOiqGis eveGn /xev ro) yXojrroeihel pLopicp, 
ov rravrl^ 8' op^olajs dXXd ra> aKpcp /xaAtcrra, hid 
rovro roig ixOvgi rovr d(j)a)piGrai pLovov. 

'ETTt^u/xtav 8' e;^et rpocfirjs rd ^cpa Trdvra cos 
exovra aiGOrjGiv rrjs rjhovrjs rrjs yivopievrjs eK rrjs 
rpo(f)rjs' r) ydp eiTidvpLia rod rjheos eoriv. dXXd rd 
fxopiov ovx dpioiov rovro ttolgiv, cL rrjv aiGdrjGiv 

10 TTOiovvrai rrjs rpocf)rjs, dXXd rois piev drroXeXvpLevov 
roZs he TrpoGTrecfjVKOs , ogois pir)hev epyov virapxei 

^ [ttjs Tpo<l)T}s xcipi*'] praecedentium interpretationem seclusi, 
cetera correxi : t^s" ev toIs x^H-'^^^ earlv r) aiadrjois {els olaQriaiv 
Z) TO fiev (/xcv TO EYZ) yXcoTTOCLbes e^ei (e;^ei oni. Z) fi6pu)v 
vulg. * navri Z : Travr^j vulg. 



Among the factors which contribute to the de- 
formity of the crocodile's tongue is the immobihty 
of its lower jaw, to which the tongue is naturally 
joined. We must remember, however, that the 
crocodile's jaws are topsy-turvy ; the bottom one is 
on top and the top one below ; this is clearly so, 
because in other animals the top jaw is the immovable 
one. The tongue is not fixed to the upper jaw (as 
one might expect it to be) because it would get in 
the way of the food as it entered the mouth, but to 
the lower one, which is really the upper one in the 
wrong place. Furthermore, although the crocodile 
is a land-animal, his manner of life is that of a fish, 
and this is another reason why he must have a tongue 
that is not distinctly articulated. 

Many fish, however, have a fleshy roof to their 
mouths. In some of the fresh-water fish — e.g. 
those known as Cyprinoi — it is very fleshy and soft, 
so that casual observers think it is a tongue. In 
fish, however, for the reason already given, the 
tongue, though articulated, is not distinctly so ; yet, 
inasmuch as the power also of perceiving tastes 
resides in the tongue-like organ, though not in the 
whole of it equally but chiefly in the tip, therefore on 
this account in fish the tip only is separate from the 

Now all animals are able to perceive the pleasant 
taste which is derived from food, and so they have a 
desire for food, because desire aims at getting that 
which is pleasant. The part, however, by which this 
perception or sensation of the food takes place, is 
not identical in all of them, for some have a tongue 
which moves freely and loosely, others (which have no 
vocal functions) have a tongue that is fastened down. 



661 a 

(f)iov7]g, Kal TOLS jLtev OKXiqpov roZs he /LtaAa/cov 

•q crap/ca>8es'. 8to Kal rols yLoXaKoorpaKois, olov 
Kapd^oLs Kal Tols roiovroiSy ivros vTrdp^eL n rov 

15 aropLaros tolovtov, Kal rots fiaXaKLOis, olov 07]7TLaLS 
Kal TToXvTTOGLv . TcDv 8* ivTopLOJV ^cpajv Ivitt fxev 
ivros €)(eL ro toiovtov pLopiov, olov to tcDv ju,t»p- 
pir^KUJV yivos, djaavrcos 8e Kal rcjv oorpaKoheppaov 
TToXXd' rd 8' Iktos, olov Kevrpov, aop.(f)6v 8e rrjv 
<f)voLV Kal KotXov, wad^ dpia rovrco Kal yeveadai Kal 

20 Tr)v rpo<f)riv dvaairdv. hrjXov 8e rovro evrt t€ pLVLcov 
Kal pLcXiTTajv Kal Trdvrcov tojv toiovtcjv, ert 8' 
€7T* ivLOJV TcDv oGTpaKohlppiOJV Tols ydp 7Top(j)vpais 
TOcravTTjv e;!^et SvvapiLV rovro ro ptopLov ojore /cat 
rGiV KoyxvXiojv hiarpv7Ta)GL rd oarpaKov, olov rojv 
arpopL^atv oh heXed^ovaiv avrds. ert 8' ot r 
olarpoL Kal ol pLvajTres ol pLev rd rdJv avSpajirajv 

25 ol 8e Kal rd rwv dXXojv t,(l)0)v Sepptara hiaipovoiv, 
iv piev ovv rovroig roXg t,a)OLs -q yXojrra roiavvq 
TTjV (f)VOLV earivy woirep dvrLGrp6(f)a)s e^ovoa rep 
pLVKrrjpL ro) rdJv eXe^dvr ojv Kal ydp eVetVots" rrpog 
^oiqdeiav 6 pLVKri^p, Kal rovrois rj yXcorra dvrl 
Kevrpov iorLV. iirl 8e rchv dXXojv ^cpcov rj yXcorra 

80 TTavrajv iorrlv otavrrep elVo/xev. 

« Under this name Aristotle probably includes several 
species of Purpura and Murex. Tyrian purple (6, 6' dibrom- 



Some again have a hard tongue ; others a soft or 
fleshy one. So we find that even the Crustacea — e.g. 
the Crayfish and such — have a tongue-Hke object 
inside the mouth, and so have the Cephalopods — e.g. 
the Sepias and the Octopuses. Of the Insects, some 
have this organ inside the mouth (e.g. the Ants), 
and so have many of the Testacea. Others have it 
outside, as though it were a sting, in which case it is 
spongy and hollov/, and so they can use it both for 
tasting and for drawing up their food. Clear ex- 
amples of this are flies and bees and all such creatures, 
and also some of the Testacea. In the Purpurae," for 
instance, this " tongue " has such strength that they 
can actually bore through the shells of shellfish with 
it, including those of the spiral snails which are used 
as baits for them. Also, there are among the gad- 
flies and cattle-flies creatures that can pierce through 
the skin of the human body, and some can actually 
puncture animal hides as well. Tongues of this sort, 
we may say, are on a par with the elephant's nose ; 
in their tongue these creatures have a useful sting 
just as the elephant has a handy implement in his 

In all other animals the tongue conforms to the 
description we have given. 

indigo) is obtained from Murex brandaris. For the boring 
powers of these creatures' tongues see the reference for 
Purpura lapillvs given by Ogle (Forbes and Hanley, Brit, 
Mollusca, iii. 385). 



*E;)^OjLtevov 8e rtDv elp-qixivojv 'q rcov oSovrcov 

35 ecrrt (f)VGL? rois t,(joois, kol to arofxa ro Trepi- 

^xoy^^vov VTTO Tovrcov /cat avveGrrjKos €k tq-utcov, 

661 b Tots' [xev ovv aAAots" r] roJv oSovrcov (f>vaL9 Koivrj 

jLtev eVt Ti^v T-r]? rpo^rjs epyaoiav v7Tdpx€L, x^^pt? 

8e Kara yevq rot? juev dA/crJ? X^P^^> '^^^ ravrrjs 8t- 

r)prjlJL€V7)S, iTTL T€ TO 7T0L€LV Kal TO /Xt) TTOLGXCIV 

TO, fi€V yap aii(j)oZv eVe/cev e;)^ft, /cat tou ^t^ Tradetv 
6 /cat ToO TTOtetF, otov ocra oapKocfxiya rcov dyplajv 
rrjv <j)VGLV ecTTtV, Tct Se ^orjOelas X^P^^» axjirep 
TToXXd ra)v dypicjv /cat tcDv 'qfiepajv. 

*0 3' dvOpOJTTOS TTpOg T€ TI^V KOLVTjV XP'^^^^ KoXcJS 

€;\;et rrecjiVKOTag' rovg fiev Trpoadlovs o^ets", tva 
Statptoot, TOWS' Se yoiK^iovs irXareZs, Iva Xeaivcoaw 
10 opl^ovGL 8' eKarepovs ol KvvoSovres, jiiaoi rrjv 
(f)VGLV dfJL(f)OT€pcjov 6vT€S' TO Tc yap jjilaov dii<j)OT€pa>v 
fi€T€X^i' ra)v a/cpcov, ot Tt /cuvo8ovTes' rfj fJLev 
diets' T7y 8e TrAarets" eloiv opioicjs 8e /cat €7rt 
Toiv ciAAcov t^ipcjv, oaa {jltj navras exovoiv diets' 
— pidXiora he /cat toutous" TotouTous' /cat toctou- 
Tous' Trpos" Tr)V 8tdAe/CTOv ttoAAo. ydp Trpo? Tr]V 


The subject which follows naturally after our pre\'ious Teeth- 
remarks is that of the Teeth. We shall also speak 
about the Mouth, for this is bounded by the teeth 
and is really formed by them. 

In the lower animals teeth have one common 
function, namely, mastication ; but they have addi- 
tional functions in different groups of animals. In 
some they are present to serve as weapons, offensive 
and defensive, for there are animals which have 
them both for offence and defence (e.g. the wild 
carnivora) ; others (including many animals both 
wild and domesticated) have them for purposes of 

Human teeth too are admirably adapted for the 
common purpose that all teeth subserve : the front 
ones are sharp, to bite up the food ; the molars 
are broad and flat, to grind it small ; and on the 
border between the two are the dog-teeth whose 
nature is intermediate between the two : and just as 
a mean shares the nature of both its extremes, so 
the dog-teeth are broad in one part and sharp in 
another. Thus the provision is similar to that of 
the other animals, except those whose teeth are 
all sharp ; but in man even these sharp teeth, in 
respect of character and number, are adapted 
chiefly for the purposes of speech, since the 



681b ^ 

15 yeveoLV tojv ypajJLfidTCov ol Trpoodioi tojv oSovtojv 

"Evta he TOJV ^wojv, wuTrep etVo/xev, rpo(f)rjg X^P'-^ 
€)(€L jiovov. ooa §e Kal rrpos ^orjOetdv re /cat rrpo^ 
dXK-qv, rd fxev ;)^auAioSovTa9 e;^et, KaBdirep vs, rd 
S' d^el? Kal eVaAAarrovra?, odev Kap)(ap6SovTa 

20 /caAetrat. eVet ydp iv rolg oSovglv tj lax^s avrcjv, 
rovTO he yivoLT dv hid ttjv 6^vTr]ra, ol y^pr^uipioi 
TTpds TTjV dXKrjv ivaXXd^ epLTTiTrrovoiv, ottojs p-y) 
dp,^XvvojvTai rpi^opevoL npog aXXt^Xovg. ovhev he 
rcov t,(jpcxjv eorlv dpa Kap-)(ap6hovv Kal )(avXL6hovv, 
Sta TO pLTjhev pdnqv TTOielv rrjv (f)vaLV p.rjhe Trepi- 

25 epyov eoTL he rajv p.ev hud 7rX7]yrJ5 r) ^oijOeia, 
Tcbv he hid hi^y pharos, hiorrep at ^T^Aetat rwv vtov 
haKvovGiv ov ydp e)(ovGi ■)(^avXi6hovras . 

(Ka^oAou he ;Ypea»v tl Xa^elv, o Kal eirl rovrcov 
Kal errl ttoXXojv tojv vorepov Xe-xdriaopiivcov earat 
XpT](Jt'P'OV. rcbv re ydp Trpo? aA^r^v re Kal ^orjdeiav 

30 opyavLKcjjv pLoploJV eKaara aTTohihcoGiv rj (pvoig rots 
hvvap,evoL? XpT]<^daL p.6vois "?) juaAAov, /xaAtcrra he 
TO) /xaAtcrra, olov Kevrpov, TrXrJKTpov, Kepara, 
XavXiohovra? Kal ei tl toiovtov erepov. errel he rd 
dppev luxvpdrepov Kal BvpuKojrepoVy rd /xev piova 
TO, he pidXXov ex^t' to. roiavra rojv /xoptojv. oaa 

85 pi,ev ydp dvayKaXov Kal rots" dj^Xeaiv ^x^iv, olov rd 
TTpos rr^v Tpo</)7yv, exovai jLtev rjrrov 8' exovGLVy oaa 
he TTpds piTjhev ra>v dvayKaicoVy ovk exovoLV. Kal 

" See note on 644 a 17. 


front teeth contribute a great deal to the formation 
of the sounds. 

As we have said, the teeth of some of the animals 
have one function only, to break up the food. Of 
those animals whose teeth serve also as a defence 
and as weapons, some (like the SA\ine) have tusks, 
some have sharp interlocking teeth, and are called 
" saw-toothed " as a result. The strength of these 
latter animals lies in their teeth, and sharpness is 
the means of securing this ; so the teeth which are 
serviceable as weapons are arranged to fit in side by 
side when the jaws are closed to prevent them from 
rubbing against each other and becoming blunt. No 
animal has saw-teeth as well as tusks ; for Nature 
never does anything without purpose or makes any- 
thing superfluously. These teeth are used in self- 
defence by biting ; tusks by striking. This explains 
why sows bite : they have no tusks. 

(At this point we should make a generalization, "The more 
which will help us both in our study of the foregoing J-^^^ F^^ 
cases and of many that are to follow. Nature allots 
defensive and offensive organs only to those creatures 
which can make use of them, or allots them " in a 
greater degree," " and " in the greatest degree " to 
the animal which can use them to the greatest ex- 
tent. This applies to stings, spurs, horns, tusks, and 
the rest. Example : Males are stronger than females 
and more spirited ; hence sometimes the male of a 
species has one of these parts and the female has 
none, sometimes the male has it "in a greater degree." 
Parts which are necessary for the female as well as 
for the male, as for instance those needed for feed- 
ing, are of course present though " in a less degree " ; 
but those which serve no necessary end are not 



662 a Slcl rovTO Tcov iXdcf)OJV ol jJLev appevcs e^ovoi 
Kepara, at 8e ^7]Aetat ovk exovcnv. hia^epei 8e 
/cat ra Kepara rwv dr]\eicJL)v ^otov /cat rcov ravpcjv 
ofiOLCOs Se Kal iv roZs Trpo^drois. /cat TrXrJKrpa 

6 Tojv dppevcov ixovTcov at TroXXal rcov drjXeioJv ovk 
exovGLv. COS" S' avTOJS €;^et rovro Kal ivl rwv 
dXXojv rcov roLovrojv.) 

Ot 8' LxOveg Trdvres etcrt KapxapoSovre? , 7TXr]v 
rod ivos rod KaXovfjLevov uKdpov rroXXol 8' exovGi 
Kal iv rats yXojrr ais ohovras /cat iv rots ovpavols. 
rovrov 8* atrtov on dvay/catov iv vypoZs ovol 

10 TrapeLuSex^crdaL ro vypov dfia rfj rpo(f)fj, Kal rovro 
raxio)^ iKTrifirreiv. ov yap eV8e;\;eTat Xeaivovras 
SiarpL^eLV elupioL yap dv ro vypov els rds KoiXias. 
8ta rovro iravres elalv d^els npos rrjv hiaipeoiv 
[xovoVy Kal^ TToXXol Kal TToXXaxfj, tva avrt rod 
Xeaiveiv els 77oAAa Kepjiarit^atoi rco rrXr^dei. yapujjol 

15 8e 8ta TO rrjV dXKTjv axehov aTracrav avrols 8ia 
rovra>v etvai. 

*'E;(et Se /cat rrjv rod arojJLaros (f>vcnv rd t,cpa 
rovrcov re rcov epyojv eVe/ca /cat en rrjs dvaTTVorjs, 
oaa dvaiTveZ rcov ^cocov Kal Karaipvx^rau Ovpadev. 
7] yap (j>vois avTY] Kad^ avri^v, cooTrep et7ro/xev, rois 

20 KOLVols ndvrojv [xopLOis els TroAAa rcov tStojv /cara- 
Xprjraiy olov Kal irrl rod Gr6p.aros rj fiev rpocfnj 
Trdvrcov kolvov, tj S* dXKTj nvcJov 'lSlov Kal 6 Xoyos 
iripcoVy en 8e rd dvarrveZv ov Trdvrcov kolvov. tj 8e 

^ sic P : hialpcaiv. tto-Xlv koI vulg. 

o Probably the parrot-fish. Cf. 675 a 3. 


present. Thus, stags have horns, does have not. 
Thus, too, cows' horns are different from bulls' horns, 
and ewes' from rams'. In many species the males 
have spurs while the females have not. And so with 
the other such parts.) 

All fishes are saw-toothed except one species, 
the Scarus.'* Many of them have teeth on their 
tongues and in the roof of the mouth. This is 
because as they live in the water they cannot help 
letting some of it in as they take in their food, and 
they have to get it out again as quickly as possible. 
If they failed to do so, and spent time grinding the 
food small, the water would run down into their gut. 
So all their teeth are sharp and intended only for cut- 
ting up the food. Further, they are numerous and 
placed all over the mouth ; so by reason of their 
multitude they can reduce the food into tiny pieces, 
and this takes the place of the grinding process. 
They are also curved ; this is because practically the 
whole of a fish's offensive force is concentrated in 
its teeth. 

The mouth, too, is present in animals on purpose Mouth, 
to fulfil these same offices, but it has also a further 
purpose, at any rate in those animals which breathe 
and are cooled from without — namely, to effect re- 
spiration. As we said earlier. Nature will often quite 
spontaneously take some part that is common to all 
animals and press it into service for some specialized 
purpose. Thus, the mouth is common to all animals, 
and its normal and universal function has to do with 
food : but sometimes it has an extra function, peculiar 
to some species only : in some it is a weapon, in others 
a means of speech ; or more generally, though not 
universally, it serves for respiration. Nature has 



632a ^ ^ 

(j)VGis airavra ovvriyayev els eV, TTOiovaa Sta^opdv 

avTOV rod jiopiov Trpo? ras" rrjs epyaaias hiacjiopas. 

25 Sto TO, /xeV ecrrt ovGTO^Lojrepay ra Se /xeyaAoaro/xa. 
ocra jLtev ydp Tpo(j>T]s kol dvaTTVorj? Kal Xoyov -x^dpiv, 
avGTOfjLcjorepa, rwv Se j^orjOeias X^P^^ '^^ H'^^ 
Kapxo-pohovra Trdvra dveppojyora- ovorjg yap 
avTols rrjs dXKrjg iv rols ^ijyiiaoi xPV^^I^ov ro 
jjLeydXrjv etvac ttjv dvdrrTV^Lv rod OTOjiaros' TrXeloai 

80 yap Kal Kara fieit^ov hrj^erai, ouovrrep dv iirl to 
TrXeov dveppcoyr] ro Grof-ta. exovGi 8e /cat ra>v 
IxOvoJV ol hrjKriKol /cat GapKo^dyoi roiovrov aro/xa, 
ol he fjiTj GapKO(j)dyoL fivovpov roLovrov yap avrols 
Xpr}OLfxov, eKelvo 8e dxpy]crrov. 

Tot? S' opviGiv eon ro KaXovfj.evov p'uyxps aro/xa* 

35 rovro yap dvrl ;)^etAtov /cat ohovrojv exovGLV. 8ta- 
662 b (jtepei he rovro Kara rds XP'^^^^^ ^^^^ "^^^ ^orjdeias. 
rd fiev yap yafiipcovvxo^ KaXovfieva hid ro oapKO- 
(jiayelv Kal piiqhevl rpe^eGdai Kaprra) yapujjov e;^et rd 
pvyxos drravra' ;)^/37]crt/xov ydp irpos rd Kparelv /cat 
^laGriKcorepov roiovro 7r€cf)VK6g. r) 8* dA/o] ev 
5 rovro) re Kal rots ovv^i' 8td /cat rovs ovvxols 
yapujjorepovs exovGLV. rdv 8' d'AAcov e/cdcrroj npos 
rdv ^iov XPV^'-P'OV ecrrt rd pvyxos, olov rols p-ev 
hpvoKOTTOLs LGxvpdv Kal gkXtjpov, Kal Kopa^L Kal 
KopaKojheGi, roXg he puKpols yXa(f)vpdv irpos rds 
GvXXoyds rcbv KapircJov Kal rds Xiqifjeis rwv t,(x)- 

10 hapiojv. OGa he 7Torj(f)dya Kal ocra Trap^ eXt] ^fj, 


brought all these functions together under one part, 
whose formation she varies in the different species to 
suit its various duties. That is why the animals 
which use their mouths for feeding, respiration and 
speaking have rather narrow mouths, while those 
that use them for self-defence have wide and gaping 
mouths. All the saw-toothed creatures have these 
wide mouths, for their method of attack is biting, and 
therefore they find it an advantage to have a mouth 
that will open wide ; and the wider it opens the 
greater the space the bite will enclose, and the 
greater the number of teeth brought into action. 
Biting and carnivorous fishes have mouths of this 
sort ; in the non-carnivorous ones it is on a tapering 
snout, and this suits their habits, whereas a gaping 
mouth would be useless. 

In birds, the mouth appears in the form of a beak, Beak, 
which serves them instead of lips and teeth. Various 
sorts of beak are found, to suit the various uses in- 
cluding defensive purposes to which it is put. All 
of the birds known as crook-taloned have a curved 
beak, because they feed on flesh and take no vegetable 
food : a beak of this form is useful to them in master- 
ing their prey, as being more adapted for the exertion 
of force. Their beak, then, is one weapon of offence, ^ 
and their claws are another ; that is why their claws 
are exceptionally curved. Every bird has a beak 
which is ser\-iceable for its particular mode of life. 
The woodpeckers, for instance, have a strong, hard 
beak ; so have crows, and other birds closely related 
to them ; small birds, on the other hand, have 
a finely constructed beak, for picking up seeds and 
catching minute animals. Birds that feed on herb- 
age and that live by marshes (e.g. swimmers and 



662 b ^ ^ ^ ^ / ^ ^ X vxx 

KaOdirep ra ttAcoto, Kal ureyavoTTOoa, ra jJLev aAAov 
TpoTTOv xp'^f^^H'OV ex€i TO pvyxos, ra 8e TrXarvpvyxC' 
avrcov ecrrtv tolovtco yap ovri paStcu? hvvarai 
6pvG(j€LV, a)<j7T€p Kal Tojv TerpaTToScjov TO rrjg vo?' 
Kal yap avr-q pL^o(f)dyos. €TL 8' exovai Acat ra 
15 pit,o^dya Tcov opviwv Kal rcJbv opLOLO^LCov eVta ra 
aKpa rod pvyxovs /ce;^apay)LteVa* 7Tor]^dyois yap 


Hepl fiev ovv rcJov dXXcov [loptajv tcov iv rfj 
Ke(f)aXfj ux^^ov etpr^rai, rcov 8' dvdpojTTWv KaXelrai 
TO pLera^v rrj? K€(f)aXrjg Kal rod avx€vos TrpoaajTTOVf 
20 a770 rrjs rrpd^eajs avrrjs ovopLaaSiv^ cos €0lk€V' hid 
yap ro jjlovov opdov etvac rwv i,cx)(x)v (jlovov Trpoa- 
codev OTTCJTTe Kal rrjv (f)a>vr]v et? to Trpoaco 8ta- 

II. liepl 8e Kepdrojv Ae/CTeov Kal yap ravra 
7T€(^i;/c€ Tots' exovoiv iv rfj K€(f)aXfj. e;(et 8* ovSev 

25 fJiTj t,a)or6KOV. KaO^ opioioriqTa 8e Kal p.€ra(f>opdv 
Xiyerai Kal irepcov rivcbv Kepara' dAA* ouSevt 
avTOJV TO epyov rod Keparog VTrdpx^i" ^o-qdeias 
yap Kal aA/CT^s" X'^P'-^ exovoi to, ^(pOTOKa, o rcbv 
dXXojv tCjv XeyopL€v<jJv ex^iv Kepas ovh^vl ovp.- 
^eprjKev ovSev yap XPV'^^^ '^'^^^ Kepaoiv ovr 

80 djJLvvopevov ovre Trpos to KpaTelv, direp lox^os 
€otIv epya. doa pcev ovv TToXvaxf-^yj tcuv ^oJcov, 
oi;Sev ex^t Kepas. tovtov 8' a'criov otl to pLev 
Kepas ^oTjQeias aiTLov Iotl, toIs Se ttoXvox^^^olv 
VTidpxovoiv €Tepai ^orjOeiai' SeSojK€ yap rj (j)VGis 

Tols pi^V OVVXOLS Tols 8' oSoVTa? pLaXTjTlKOVSt TOIS 

" Under this heading all the Mammalia known to Aristotle 


web-footed birds) have a beak adapted for their 
mode of hfe, a special instance of which is the broad 
beak, which enables them to dig for roots easily, just 
as the broad snout of the pig enables it to dig — an 
example of a root-eating quadruped. These root- 
eating birds and other birds of similar habits some- 
times have sharp points at the end of the beak. This 
enables them to deal easily with the herbaceous food 
which they take. 

We have now, I think, spoken of practically all 
the parts that have their place in the head ; but 
in man, the portion of the body between the head 
and the neck is called the Prosopon (Face), a name 
derived, no doubt, from the function it performs. 
Man, the only animal that stands upright, is the 
only one that looks straight before him (^prosothen 
opope) or sends forth his voice straight before him 
(jproso, opd). 

II. We still have to speak of Horns : these also, HomR 
when present, grow out of the head. Horns are 
found only in the Vivipara ; though some other 
creatures have what are called horns, owing to their 
resemblance to real horns. None of these so-called 
horns, however, performs the function proper to horns. 
The reason why the Vivipara have horns is for the 
sake of self-defence and attack, and this is not true 
of any of these other creatures, since none of them 
uses its " horns " for such feats of strength either 
defensively or offensively. The polydactylous ani- 
mals," moreover, have no horns, because they possess 
other means of defence. Nature has given them claws 
or teeth to fight with, or some other part capable of 

are included, except ruminants, solid-hoofed animals, and 



662b ^ ^ 

35 S' aAAo TL jJLopLov LKavov ajjivveiv. Tojv Se St^*^^^^ 

663 a ra fiev rroXXa Kepara e;^et irpos olXk-qv, /cat rwv 

[lojvvxojv eVta, ret 8e Kal Trpos ^oiqdeiav, ogols^ pLrj 

SeSojKev T) (f>VGLS dXXr]v dXKrji> npos oojTr^piav, olov 

Ta)(VT7]Ta Gcoiiaros, KaOdrrep roZs lttttols ^e^orjOrj- 

K€V, rj jjLeyeOog, cooTrep rat? Kap.rjXoLS' Kal yap 

6 fieyedovs VTrep^oXrj rrjv 0.770 rwv dXXcov ^cocov 

<f)dopdv LKavT] Ka)Xv€LV, oTTep GVfi^e^'qKe rals Kafx-q- 

XoLS, €Tt 8e jJLaXXov rots iXecjjaaLV. ra Se ;)^auAt- 

oSovra, wanep /cat ro tcjv vd)v yivos, hi-)(aXov (pv).^ 

"Ocrots" S' dxpT](yTOs 7T6(j)VK€v Tj TOJV Kepdrojv 

e^oxT], TOVTOLs TTpOGTeOeLKev irepav ^o'qdeiav r) 

10 (f)VGLS, OLOV rats' /xev iXdcj^oig rdxo? {ro yap fxe- 
yedog avrdjv /cat to 7roAuo-;(iSe9 jLtaAAoy ^Xdirrei 7) 
ccx^eAet), /cat ^ov^dXois he /cat hopKdGL {irpos eVta 
/xev yap dvOiGrdpieva rots Kepaaiv dp^vvovrai, rd Se 
drjpiwSr] /cat /xa;^ijLta d7TO(f)€vyovGL) , rols he ^ovdGOLs 
(/cat ydp TO-UTOis yafii/jd rd Kepara 7re(f)VKe rrpos 

15 dXXriXa) rrjv rod TrepLrrcopLaro? d(f)€GLV' rovrco ydp 
dpivverai (jio^ijdevra- /cat ravrrj Se rfj npoeGCL Sta- 
ooj^erat erepa. dpia S* t/caras" /cat irXeiovs ^or^^etas" 
01) SeSa>/cev t^ (f)VGLs rols avrols. 

"Ecrt Se TO, TrAetara rojv K€paro(f}6pojv Si;^aAa, 
Aeyerat Se /cat picovvxov, ov KaXovGiv 'IvSt/cov oVov. 

20 To, /xev ovv TrXelora, Kaddirep /cat ro otu/xa 
hifipr^rai rdJv l,d)OJV ots Tiotetrat tt^v KcvrjOLV, Se^tov 
/cat dptorrepov, /cat Kepara Svo 7Te(j>VKev e;j(etv Sta 

1 Sc post oaoi? vulgr. : del. Piatt, Thurot 
2 <ov> Ogle. 

■ Cf. above, on 6 J-8 a 16. 

* The European bison. 

* This is probably the Indian Rhinoceros. This account 


rendering adequate defence. Most of the cloven- 
hoofed animals, and some of the solid-hoofed, have 
horns, as weapons of offence ; some have horns for 
self-defence, as those animals which have not been 
given means of safety and self-defence of a different 
order — the speed, for instance, which Nature has 
given to horses, or the enormous size which camels 
have (and elephants even more), which is sufficient 
to prevent them from being destroyed by other 
animals. Some, however, have tusks, for instance 
s^vine, although they are cloven-hoofed. 

In some animals the horns are a useless appendage," 
and to these Nature has given an additional means 
of defence. Deer have been given speed (because 
the size of their horns and the numerous branches 
are more of a nuisance to them than a help). So 
have the antelopes and the gazelles, which, although 
they ^^ithstand some attackers and defend them- 
selves with their horns, run away from really fierce 
fighters. The Bonasus,^ whose horns curve inwards 
to meet each other, protects itself when frightened 
by the discharge of its excrement. There are other 
animals that protect themselves in the same way. 
Nature, however, has not given more than one 
adequate means of protection to any one animal. 

Most of the horned animals are cloven-hoofed, 
though there is said to be one that is solid-hoofed, 
the Indian Ass," as it is called. 

The great majority of horned animals have two 
horns, just as, in respect of the parts by which 
its movement is effected, the body is divided 
into two — the right and the left. And the 

of it comes from the Indica of Ktesias of Knidos, quoted in 
Photius's Bibliothecay Ixxii. pp. 48 b 19 (Bekker) foil. 

H 219 


663 a ^ ^ ^ ^ ^ 

rr)V avrr]v atVtav^- ecrrt 8e kol jjlovokI par ay olov 6 

T* opv^ Kal 6 'IvSt/cos" KaXovjxevos ovos". ecrrt 8' o 

jLtey opu^ 8/;)^aAoi^, o 8' ovo? fjLcovvxov. e;^et 8e to, 

25 jjiovoKepara to Kepas iv toj pLdaa) rrjs K€(f)aXrjs' 
ovTco yap eKarepov rojv jjLcpaJv /xaAtar' av e;(Ot 
Kepas €V TO yap fxeoov 6p.0LCx)s kolvov aii^oripcov 
tCjv iaxo-Tcov. €vX6ya)s 8' dv 8d^et€ piovoKepojv 
€LvaL TO ficovvxov rod hi^aXov fxdXXov ottXt] yap 
Kal XV^V '^V^ avrrjv e;\;et Kepari <f)VGLV, cucr^' dfia 

80 /cat TOt? auTots" ")} ox^cri'S yiverai rajv ottXojv /cat 
rd)v Kepdrcxjv. en 8' t^ CT;(tcrt? /<at to 8i;)^aAov xaT 
eXXeixpLV rrjg (fivaews iariv, war* euAoya>S" Tots" 
fjLa>vvxoLS iv Tat? OTiAat? 8ouo'a rrjv vrrepox'^v 
rj (f)VGis dvcoOev dcjieXXe Kal fjLovoKepwv irrolrjaev. 
^OpddJs 8e /cat TO e77t rrjg K6(f)aXrjs TTOLrjuai rrjv 

85 T(vv Kepdrojv <f)vcnv, dXXd firj Kaddnep 6 Algwttov 
Mco/xos" StajLte/Lt(^eTat tov ravpov on ovk eiri rots 
663 b wpLOLs €X€L rd Kepara, odev rag TrXrjyds eTrotetT* 
dv laxvpordras, aAA' €7tI tov doOeveordrov fiepov? 
TTJs Ke(f)aXrjS' ov yap o^v ^Xiirajv 6 MojjLtos" TauT 
iTTeTLpLr^Gev. warrep yap Kal el eTepa)di ttov rod 
5 acofiarog Kepara i7Te(f)VKeL, ^dpos dv rrapeZx^'^ ^^~ 
Xojs ovhev ovra XP'^^^^^ f^^^ ejjLTToSia rujv epya)V 
TToAAois" Tjv, ovra> Kal irrl rwv cjpLOJV 7re<f)VK6ra. ov 
yap fjLovov XP'^ aKorreZv rroBev laxvporepai at ttAt^- 
yat, dAAa /cat TTodev rroppcorepaf ojcjr errei ^^'Ctpas" 
fxev OVK exovGLV, errl 8e rojv TTohujv dhvvarov, iv 8e 

^ avTTjv aiTiav Peck : alrlav Tavrrjv Vlllg". 
* See Babrius, Myth. Aesop, lix. 8-10. 


reason in both cases is the same. There are, how- 
ever, some animals that have one horn only, e.g. 
the Oryx (whose hoof is cloven) and the " Indian 
Ass " (whose hoof is solid). These creatures have 
their horn in the middle of the head : this is the 
nearest approximation to letting each side have its 
own horn, because the middle is common equally to 
both extremes. Now it is quite reasonable that the 
one horn should go with the solid hoof rather than 
with the cloven hoof, because hoof is identical in 
nature with horn, and we should expect to find 
divided hoofs and divided horns together in the same 
animal. Again, division of the hoof is really due to 
deficiency of material, so it is reasonable that as 
Nature has used more material in the hoofs of the 
solid-hoofed animals, she has taken something away 
from the upper parts and made one horn only. 

Again, Nature acted aright in placing the horns 
on the head. Momus in Aesop's fable " is quite 
\\Tong when he finds fault with the bull for having 
his horns on the head, which is the weakest part of 
all, instead of on the shoulders, which, he says, 
would have enabled them to deliver the strongest 
possible blow. Such a criticism shows Momus 's 
lack of perspicacity. If the horns had been placed 
on the shoulders, as indeed on any other part of the 
body, they would have been a dead weight, and 
would have been no assistance but rather a hindrance 
to many of the animal's activities. And besides, 
strength of stroke is not the only point to be con- 
sidered : width of range is equally important. 
Where could the horns have been placed to secure 
this ? It would have been impossible to have them 
on the feet ; knees with horns on them would have 



663b ^ ^ 

Tots" yovaGLV ovra rrjv kolijliJjlv eKcoXvev av, avay- 

10 KOLOV CUCT77ep VVV €)(^OVaiVy €7TL TTJ? K€<f)aXTJS €;^€tV. 

dfia Se /cat npog ras ctAAa? klvt^g€ls rod acofjiaros 

dvejJLTToSLGTa 7T€(f)VKeV OVTCO jJidXiGTa. 

"Eart 8e rd Kepara St' oXov ureped rot? iXd(l)ois 
fjLovoLs, KoX diTO^dXXeL piovov, ev€Kev pL€V cic^eAetas" 
Kov(f)Ll,6pievov, ef dvdyKTjg 8e Sta to fSdpos. tojv S* 

15 a'AAcov rd Kepara p-^xpi nvog KolXa, rd 8' a/cpa 
areped Sid to TTpos rds TrXrjyds tovt etvat XP"^' 
Gifiov. oTTOjg 8e /xrySe to KotAov ao^eves" ^7 o^ 
7T€(j)VKev €K Tov Sepp^aTog, iv rovrco^ iv^pp.ocrraL 
(rdy^ arepeov ck tojv octtcDv outco ydp /cat Ta 
K€paTa exovTa Trpog aAK'T^v t€ XPV^'-I^^'^^'^* eoTt* 

20 /cat TTpog TOV d'AAov ^lov dvoxXoraTa. 

TiVo? /xev ovv eveKGV r) tojv KepaTOJV (jivaig, 
elpr]Tai, /cat 8ta TtV atVtav tcz /xev exovuL ToiavTa 
Td 8' ou/c exovGiv 

Yiojg he TTJg dvayKaiag (jjvoeojg exovorrjs toIs 
virdpxovuiv i^ dvdyKrjg rj /caTO, tov Aoyov (fyvaug 
€V€Kd tov KaTaKexp'TjTai, Xiyojpiev. 

86 WpojTOV pukv ovv TO GOjpLaTOjhcs /cat yeajSes" TrXelov 
vrrapx^t Tolg pbell^oGL tojv l,qjojv, K€paTO(f)6pov Se 
pLLKpov irdpLTTav ovhev ta/xev eAap^tcrTOV yap CCTTt tojv 
yvojpLt,opL€vojv SopKag. Set Se ttjv <j>voLV Oeojpelv 
€Lg Td 77oAAa ^XenovTa' r) ydp iv Toi TravTL rj cos" eVt 

TO TToXv TO /caret (f)VGLV eGTLV. TO 8' OCTTOiSeS' eV 

^ o Peck, cf. Hist. An. 500 a 8: ov vulg., om. EPY: ov 
suprascr. Z (v. p. 46). ^ tovtco Peck : touto) 8' vulg. 

3 <To> Peck : cf. Hist. An. ^500 a 9. 

* icTTL Piatt : efi'ai vulg. : €117 av Thurot. 

• For the contrast between "necessary nature" and 


been unable to bend ; and the bull has no hands ; so 
they had to be where they are — on the head. And 
being there, they offer the least possible hindrance 
to the movements of the body in general. 

Deer alone have horns that are solid throughout ; 
and deer alone shed their horns : this is done (a) on 
purpose to get the advantage of the extra lightness, 
(b) of necessity, owing to the weight of the horns. 
In other animals the horns are hollow up to a certain 
distance, but the tips are solid because solid tips are 
an advantage when striking. And to prevent undue 
weakness even in the hollow part, which grows out 
from the skin, the solid piece which is fitted into it 
comes up from the bones. In this way the horns 
are rendered most serviceable for offensive pur- 
poses and least hampering during the rest of the 

This completes our statement of the purpose for 
which horns exist and the reason why some animals 
have them and some have not. 

We must now describe the character of that 
** necessary nature," owing to which certain things 
are present of necessity, things which have been 
used by " rational nature " to subserve a " purpose." ** 

To begin with, then : the larger the animal, the 
greater the quantity of corporeal or earthy matter 
there is in it. We know no really small homed 
animal — the smallest known one is the gazelle. (To 
study Nature we have to consider the majority of 
cases, for it is either in what is universal or what 
happens in the majority of cases that Nature's 
ways are to be found. Now all the bone in animals' 

" rational nature" see above 640 b 8-29, G41 a 25 ff., 642 a 
1 fiF., and cf. G.A. (Loeb edn.), Introd. § 14. 



663 b 

SO Tots' oiojJiaoi Toiv t^comv yecoSe? virdp^^L' Sto Krat 

TrAetaroy ev rolg iieyiGroLS dis cttl to ttoAu jSAe- 
ipavras elirelv. rrfv yovv tolovtov aajfiaTOS Trepir- 
rojfiaTLKTjv vnep^oX-qv eV TOts" fxetl^oGi tojv ^ojcuy 
VTTOLpxovaav eVt ^o-qOeiav kol to avjjLcfiepov Kara- 
Xprjrat r) (jivais, koL rrjv peovcrav i^ avdyKT]? elg rov 
85 dvoj TOTTOV Tols {JLev CIS oSovTa? /cat ;^aL'AtoSovTa? 
ciTreVet/xc, TOtS" 8' ets" Kepara. 8to tcuv Keparo- 
cfyopcov ouSev eariv dpL^iohov dvco yap ovk ep^et tous" 

664 a TTpoudiovs oSo^Tas" d^eXovoa yap evrevdev tj (f>VGLs 

TOLS KepauL 7Tpooedr]Key /cat r] hihopilvr] rpocfirj et? 
tous" oSovTa? TOUTOUS' €LS TTjv TOJV Kepdrcxiv av^-qoiv 
dvaXiGKerai. rov Se rds 9r]\eias iXd(f)ovs Kepara 
fikv fir] e^etv, Trepl 8e rovs oSovTas" opLOLcos roZs 
5 dppeoiVy aiTLOV to tt^v avrrjv etvat (J)vglv dpi(f>olv 
/cat K€paro(f)6pov, dcji'^prjrai Se to, Kepara rals 
O-qXelaLS Stct to xPV^'-H'^ /^^^ i^''? ^^^^tt jLti^Se Tot? 
dppeGLv, ^XdnreGOaL 8' tjggov 8td tt^v lgx^v. 

Tcov 8' aAAcDV i,cpajv ogols (jltj els Kepara 0,770- 

Kpiverai to TOtoi;Tov jxopiov rov Goyfiaros, evLOis 

10 /xev TcDv o8oyTCDV auTcDv errr]v^r]Ge ro jieyeOos KOLvfj 

irdvriov, eviois 8e ;(;auAtoSovTas' coGrrep Kepara e/c 

Ttav yvddojv eTTolrjGev. 

Uepl [lev ovv rcov ev rfj Ke(f)aXfj /xoptcov ravrrj 


III. *T77o 8e TT^v Ke(f)aX7]v 6 avx'^v 7Te(j)VKa)g eGri 

rot? e^ovGiv aO;)^eVa tojv i,ci)a>v, ov yap iravra 

15 rovro ro piopiov e;)^et, dAAa /xdva to, e^ovra coy 

" i.g. constituent substance. See on 648 a 2. 


bodies consists of earthy matter ; so if we consider 
the majority of cases, we can say that there is most 
earthy matter in the biggest animals.) At any rate, 
in the larger animals there is present a surplus of 
this corporeal or earthy matter, produced as a 
residue, and this Nature makes use of and turns to 
advantage to provide them with means of defence. 
That portion of it which by necessity courses upwards 
she allots to form teeth and tusks in some animals, 
and to form horns in others. And we can see from 
this why no horned animal has incisor teeth in both 
jaws, but only in the bottom jaw. Nature has 
taken away from the teeth to add to the horns ; 
so that the nourishment which would normally be 
supplied to the upper teeth is here used to grow the 
horns. Why is it, then, that female deer, although 
they have no horns, are no better off for teeth than 
the male deer ? The answer is : Both of them are, 
by nature, horned animals ; but the females have 
lost their horns because they would be not only 
useless but dangerous. The horns are indeed of no 
more use to the males, but they are less dangerous 
because the males are stronger. 

Thus in some animals this " part "^ of the body 
is secreted for the formation of horns ; in others, 
however, it causes a general increase in the size of 
the teeth, and in others again it produces tusks, 
which are like horns springing out of the jaws 
instead of the head. 

We have now dealt with the " parts " that apper- 
tain to the head. 

III. The place of the neck, when there is one, is Of the 
below the head. I say " when there is one," because oesopha^'us 
only those animals have this part which also have 



664 a ^ 

;!^aptv o avx'^v 7T€cf)VK€V ravra 8' ecrrtv o re (f)dpvy^ 

/cat o /caAoujLtevo? oloo(j)dyos . 

*0 /xev oi;v (j>dpvy^ rod TTvevfJiaTog ev€Kev ire^vKev 
hid TOVTOv yap elody^Tai ro TTvevfia rd ^wa /cat 
e/C77e/X7r€t dvanveovra /cat eKTrveovra. 8t6 to, jLti^ 

20 exovra TrXevfJLova ovk exovaiv oi)S' au;^eVa, otov 
TO TcoF IxOvcov yivo£. 6 8' oloo(j)dyos iarl 8t' ou 
-j^ rpo^T] TTopeverai cts" tt^v KotXlav a)o9* daa jjurj 
e;^et ai3;\;eVa, ouS' OLGO(f)dyov iTnS-qXoJs exovacv. 
OVK dvayKOLOV 8' e;^etv rov otcro^ayov tt)? rpocfyrjg 
ev€Kev ovdev yap -napaoKevdl^eL rrpos avr^v. €tl 

25 8e fierd rrjv rov oroixaros deaiv ivSex^rau /ceta^at 
T-qv /cotAtav evdecos, tov 8e TrXevjiova ovk ivhex^Tau. 
8et yap etvat rtva /cotvov otov avXcova, 8t' ou jLte- 
pLelraL to Trveu/xa /caret ras" dprrfpia^ els rdg 
Gvpiyyas, SLfzeprj ovra^' /cat /caAAtcrr' av ovrcos 
aTToreXol rrjv dvaTTVorjv /cat eKTTVorjv. rov 8' dp- 

80 yavou rod nepl ttjv dvaTrvorjv i^ dvay/cr^S" exovrog 
lirJKog, dvayKalov rov olao(f)dyov etvai fxera^v rod 
oropLaros /cat ri^s KoiXias. eon 8' d jLtev oloot^dyog 
GapKcoSrjs, €X^v vevpcohrj rdoiv, vevpcoSr^s ^teV, 
OTTOJs €XJ) SidraoLV eloiovorjs rrjs Tpo^rjs, oapKcoSrjs 

85 Sc, OTTOis /xaAa/cd? 7^ /<:at ei'8t8a) /cat /xt) ^XdTrrrjTai 
rpaxwopievos vtto rdJv Kariovrcov. 

'H 8e KaXovpevTj (j)dpvy^ /cat dprrjpia ovveor-qKev 

664 b e/c ;\;ov8ptt>8oL'S" aajp-aros' ov yap pLovov dvaTTVorjs 

€V€K€V ecrrtv aAAa /cat (fxjjvrjs, 8et 86 rd iljO(j)riG€LV 

pulXXov Xelov elvai /cat orepeor-qra €X€lv. /cetrai 8' 

epLTTpooOev 7] dprrjpla rod OL(JO(j)dyov , Kaiirep e/x- 

TTohit^ovaa avrdv irepl rrjv VTrohox^lv rrjs rpo(j)rjs' 

6 edv ydp rt TrapeiGpvfj ^r]p6v 7) vypdv els ttjv dprr}- 

^ 8Lfj.€prj ovra Peck : 8tfj.€pr)S ojv vulg. : Bifiepovs optos Th. 



those parts that the neck subserves — viz. the larynx 
and the oesophagus, as it is called. 

The larynx is present for the sake of the breath : 
when animals breathe in and out, the breath passes 
through the larynx. Thus creatures which have no 
lung {e.g. fish) have no neck either. The oesophagus 
is the passage by w^hich the food makes its w^ay to 
the stomach ; so those that have no neck have no 
distinct oesophagus. So far as food is concerned, 
however, an oesophagus is not necessarv'-, since it 
exerts no action upon the food ; and there is really 
no reason why the stomach should not be placed 
immediately next the mouth. The lung, however, 
could not be so placed, because some sort of tube 
must be present, common to both lungs, and divided 
into two, by which the breath is divided along the 
bronchial tubes into the air-tubes : this is the best 
method for securing good breathing, both in and out. 
This respiratory organ, then, of necessity, is of some 
length ; and this necessitates the presence of an 
oesophagus, to connect the mouth to the stomach. 
Now the oesophagus is fleshy, and it can also be 
extended like a sinew. It is sinewy so that it can 
stretch as the food enters in ; and it is fleshy so that 
it may be soft and yielding and not be damaged by 
the food grating on it as it goes down. 

What are called the larynx and windpipe are Larynx and 
constructed of cartilaginous substance, since the pur- ^'"'^i^^P^* 
pose they serve includes speech as well as respira- 
tion ; and an instrument that is to produce sound 
must be smooth and firm. The windpipe is situated in 
front of the oesophagus, although it causes it some 
hindrance when food is being admitted^ — as when a 
piece of food, no matter whether solid or fluid, gets 

h2 227- 


664 b ^ 

ptav, TTviyixovs kol ttovovs koI ^rjx^^ ;^aAe7ra? 
i/jLTTOiel. o Srj Kal davfidueLev dv rts" twv Xeyovrcov 
(x)£ ravTYj TO TTOTOV 8e;^eTat to ^coov cru/x/^atVet yap 
<f)av€pa)S ra XexOdvra ttciglv oh av Trapappvfj tl rrjs 

10 Tpo(j>r\s- TToWaxf] 8e yeXolov ^atVerat to Xeyeiv djs 
ravrr] to ttotov elohex^Tai to, ^a>a. rropos yap 
ovheis ioTLV els ttjv KOiXiav 0.770 tov nXevfiovos, 
wcTTep CK TOV OTopiaTos opojpLev TOV olaocfxxyov. 
€Ti 8' iv TOLS ep.eT0L5 Kal vavTcaLS ovk dSrjXov rrodev 
TO vypov (jyaiveTai 7Topev6pi€vov. SrjXov he Kal otl 

15 ovk evdecus els rrjv kvgtlv avXXeyeTai to vypov, 
aAA' els TTjV KoiXiav rrpoTepov to, yap ttjs KoiXias 
TTepLTTWfxaTa ^aiveTai ;\;pct)jU,aTt^etv r] IXvs rod pe- 
Xavos o'lvov GVpL^e^TjKe Se tovto rroXXaKLS (f)avep6v 
Kal inl TWV els ttjv KOiXiav Tpavp-aTOJV. dXXd yap 
loojs evrjOes ro tovs evrjOeis tujv Xoyojv Xiav 
e^eTat^eiv . 

20 *H 3' dpTTipia Tw hiaKelodai, KaOdnep eLTTop.ev, 
iv rw TTpoudev viro rrjs rpo<j)r\s cvop^AetTat* aAA* r] 
^VULS TTpos TOVTO p^epLTjxdvqTaL TTjV emyXcjTTiha. 
TavTr)v 8' OVK exovoLV diravTa Ta t,cpOTOKovvTa,^ 
aAA' oca TrXevp^ova e;(et Kal to Seppia Tpt;(CUTOV, Kal 

25 piTj (f)oXiha)Td pirjSe TTTepcoTa TTe(j)VKev. tovtols 8' 
dvTt T7]s eTTLyXojTTiSos ovvdyeTai Kal StolyeTaL 6 
cfidpvyi ovTTep TpoTTOV eKeivois' eiri^aXXeL Te Kal 
dvaiTTVGueTaL, tov (^pLevY rrvevpuaTOS ttj elaoSco Te 
Kal e^oho) dvaTTTVGGOi-Levos , rrjs 8e Tpo(/)rjs €ta- 

^ t,a)OTOKOvi>Ta] l^cLa to. evaifxa Op;le. 
* (jjL€v) supplevi et interpunctionem hie correxi. 



into the windpipe by mistake, and causes a great deal 
of choking and distress and violent coughing. This 
sort of thing occurs and can be observed whenever a 
piece of food goes the wrong way ; yet they must be 
mysteries to those who hold that animals take in their 
drink by way of the windpipe. ** And there are many 
counts on which we can show that this is a ridiculous 
opinion to hold, (a) There is no passage leading from 
the lung into the stomach, such as the oesophagus, 
which, as we can see, leads thither from the mouth. 
And again, (6) there is no doubt where the fluid dis- 
charge comes from in cases of vomiting and sea-sick- 
ness, (c) It is plain, too, that the fluid matter which 
we take does not collect immediately in the bladder, 
but goes first into the stomach. This is shown by 
the fact that the dregs of dark wine affect the co- 
lour of the residual discharge from the stomach ; and 
this colouring has often been observed in cases where 
the stomach has been wounded. Still, perhaps it is 
silly to be too minute in discussing these silly theories. 

The windpipe, as we have said, is situated in front, Epiglottis. 
and therefore is interfered with by the food. To deal 
with this difficulty, Nature has contrived the epi- 
glottis. Not all Vivipara ^ have this, but only those 
which have a lung, and a hairy skin, and are not 
covered with horny scales or feathers. Those that 
are so covered have, to serve instead of the epiglottis, 
a larynx which closes and opens, just as the epiglottis 
does in the others ; it comes down and lifts up again : 
it lifts up during the entrance and exit of the breath, 
and subsides while food is being taken, to prevent 

" See e.g. Plato, Timaeus 70 c 7, and Taylor ad loc. 
* Ogle chancres the text here to read " blooded animals,** 
which brings the statement nearer the truth. 



664b ^ ^ 

LOvcrr]g eTnTTTvaaofJievos , tva fjur^dev Trapappvfj rrpog^ 
30 Trjv dprrjpLav. iav Se rt TTXrjjjLjjLeXr^dfj napa ttjv 
TOLavrrjv KLvrjaiv /cat Trpoucjiepoixivris rrjs Tpo(j)r\s 
dvaTTvevarj ris, ^rjx^^ '^^^ TTViypiovs Trotet, KaOaTrep 
ctpr^rai. ovrco Se /caAto? fjLefjLrD^dvrjTaL Kal rj ravrr]? 
Kal 7} rrjg yXcurr-qs KLvrjais, cogt€ rrj^ Tpo<j)rjs iv [xev 
Tip GTopLari XeaLvojJLevrjs, Trap* avrrjv 8e Suovarjs, 
35 T7]v fiev oXtyaKLs VTTO Tovs oSopras 7tl7tt€lv, els 8e 
rrjv dpriqpLav Girdviov ri TrapappeXv. 

665 a OvK €X€L Se rd Xexdevra ^oia rrjv imyXiOTTiha 
Sta TO ^Tjpds elvai rds odpKas avrojv Kal to Sep/xa 


fjLopLov avrolg €K roiavrrjg oapKos Kal Ik tolovtov 
SepfJLaros avvearrjKog, aAA' avrrjg rrjs dpr-qpias 
5 Toiv ia)(dTCov ddaaov eyiver dv rj avvaycoyrj ttjs €.k 
rrjs OLKelas aapKos eTTiyXcorrihos , tjv €)(ovai rd 

At' rjv fjiev ovv alriav rd jxev ex^t, tojv l^cpcnv rd 8' 
ouk: e;)(et, ravr elpT^aOco, Kal StoTt rrjs dpriqpias rrjv 
(f)avX6rr)ra rrjg deaecjos IdrpevKev r) (f)VGLS, /X7^;^av7^- 
GapbevT] rr)V KaXovfiivrjv eTnyXcorr uSa. KeZrai 8' 

10 epLTTpooOev rj (f)dpvy^ rod oluo<^dyov i^ dvdyKTjg. rj 
fjLev ydp Kaphia eV Tot? ep^Trpoodev Kal iv pLeoco 
Kelraiy iv fj rr)v dpx^i^ ^a/xev rrjg t,a)rjg Kal Trdarjs 
Kivqoeojs Te /cat alodijoews (eVt to /caAou/xevov ydp 
epLTTpooOev T) alodriuis Kal rj KivTjcng' avrw ydp ro) 

15 Xoycp rovrcp hiojpiuraL rd epLrrpoadev Kal OTTiodev), 
6 8e TrXevpicov Kelrai ov rj Kaphia /cat rrepl ravrrjv, 
r) 8* dvaTTVorj 8ta re rovrov"^ Kal 8ta rrjV dpx^v rrjv 
iv rfj Kaphia ivvTrdpxovoav . rj 8' dvanvorj yiverai 
rots t,a>OL'S hid rijs dprrjpias' cuctt' inel rrjv Kaphiav 

^ npos PZ : -napa vulg. 



anything coming in by mistake into the windpipe. If 
there is any error in this movement, or if you breathe 
in while you are taking food, coughing and choking 
results, as I have said. But the movement of the 
epiglottis and of the tongue has been so neatly 
contrived that while the food is being masticated in 
the mouth and is passing over the epiglottis, the 
tongue seldom gets in the way of the teeth, and 
hardly ever does any food slip into the windpipe. 

I mentioned some animals that have no epiglottis. 
This is because their flesh is dry and their skin hard ; 
and thus if they had one, it would not move easily, 
because it would have to be made out of constituents 
of this sort. It is quicker to contract the edges of the 
windpipe itself than it would be to close an epiglottis, 
if, as in the hairy creatures, it w^ere made out of the 
same sort of flesh as the rest of their bodies. 

This will suffice to show why some animals have an 
epiglottis and some not ; how Nature has contrived 
it so as to remedy the unsatisfactory position of 
the windpipe in front of the oesophagus. Still, the 
windpipe is bound by necessity to be in this position 
for the following reason. The heart is situated in the 
middle of the body and in the fore part of it ; and in 
the heart, we hold, is the principle of life and of all 
movement and sensation. Both of these activities 
take place in the direction we call forw^ards : that is 
the very principle w^hich constitutes the distinction 
between before and behind. The lung is situated in 
the region of the heart, and surrounding it. Now 
breathing takes place for the sake of the lung and 
the principle which is situated in the heart : and the 
breath passes through the windpipe. So, since the 

* Tovrov SUY : tovto vulg. 



665a ^ ^ ^ 

iv rots' efJLTTpoodev 7Tpa)T7]v dvayKalov Keiadai, /cat 

20 rov (fxipvyya /cat rrjv aprripiav nporepov dvayKOLOV 
Keiddai rod oloo(f)dyov' tol {lev yap TTpos rov 
TrAeu/xova retVet /cat Tr]v Kaphcav, 6 8* els ttjv 
/cotAtav. oAa;^ 8' aet to ^eXnov /cat TLpmLrepov, 
O7T0V iJLTjSev fieiJ^ov erepov e/XTToSt^et, rod jJLev 
dvoj /cat Kdrco iv rocs /xaAAov eoriv dvco, rov 8' 

25 epiTTpoodev /cat OTTiodev ev rot? efJiTTpoadev, rov 
8e^tou 8e /cat dpLurepov ev roXs 8eftot?. 

Kat Trept jLtev au;^eVos" t€ /cat OLGO(f)dyov /cat 
aprrjpuas elprjrai, enofievov 8' cart Trept arrXdyxvcov 

IV. Taura 8' eartv tSta rail/ ivaufxajv, /cat rot? 

so jLtev drravd^ V7Tdp)(eL, rot? 8' oi3;( i;7rap;^et. rcDv 8' 
dvatfiajv ovSev e^eu unXdyxvov. Ar^jjiOKpLros 8* 
€Ot/cev oi) /caAcos" StaXa^elv irepl avrojv, elnep coi^dr] 
8ta pLLKporrjra rcov dvaijiojv t,wcov dSrjXa elvat 
ravra. avviarafjievcov yap evOecxJs rd)v ivalfxcov /cat 
rrdfiTrav ovrcov jjuKpcuv evSrjXa yiverai Kaphia re /cat 

35 '^nap' (f)aLveraL yap ev fxev rots cools eviore rpiraiois 

665 b ovGi (jrLyfirjs exovra fieyedos, TrdpLpLLKpa 8e /cat ev 

rots eK^oXlpiOLS ra)v ifx^pvcov. crt 8' a>G7rep rcov e/c- 

ros fJiopLOJV ov rrdcTL rcov avrcov XPV^^^> ciAA' e/ca- 

aroLS tSia TTeTTopiurai rrpos re rovs ^lovs /cat rds 

ictvT^CTet?, ovrco /cat rd evros dXXa Tre<^VKev aAAotS". 

Ta 8e GirXdyxya rcov alfjuariKcbv eurlv t8ta, 8to 

/cat GVvearrjKev avrcov eKaarov i^ alfJLartKTJs vXr]s. 

hrjXov 8' ev rots veoyvots rovrcov alixarcoheorepa 

yap /cat pbeyiora Kara Aoyoi^ 8ta rd elvai rd elBos 

■ Limited by Aristotle to blood-like viscera only. 


heart must of necessity be situated in the front place 
of all, both the larynx and the windpipe, which lead 
to the lung and the heart, must of necessity be 
situated in front of the oesophagus which leads merely 
to the stomach. Speaking generally, unless some 
greater object interferes, that which is better and 
more honourable tends to be above rather than below, 
in front rather than at the back, and on the right side 
rather than on the left. 

We have now spoken of the neck, the oeso- 
phagus, and the windpipe, and our next topic is the 

IV. Only blooded animals have viscera.'^ Some, but internal 
not all, have a complete set of them. As no blood- blooded 
less animals have them, Democritus must have been animals. 
wrong in his ideas on this point, if he really supposed 
that the viscera in bloodless creatures are invisible 
o^ving to the smallness of the creatures themselves. 
Against this we can put the fact that the heart and 
the liver are visible in blooded animals as soon as they 
are formed at all, that is, when they are quite small : 
in eggs they are visible, just about the size of a point, 
sometimes as early as the third day, and very small 
ones are visible in aborted embryos. Further, just 
as each animal is equipped Mith those external parts 
which are necessary to it for its manner of life and its 
motion, and no two animals require exactly the same 
ones, so it is with the internal parts : they vary in the 
various animals. 

Viscera, then, are peculiar to the blooded animals, Heart, 
and that is why each one of the viscera is formed of 
blood-like material. This is clearly to be seen in the 
new-born offspring of blooded animals ; in them the 
viscera are more blood-like, and at their largest in 



665 b 

rrjs vXrjs /cat to TrXrjdos e/x^ayeWarov /caret rrjv 

10 Trpwrrjv ovoraaiv. /capSta jLtev ovv airauLV V7Tap)(6L 
Tols IvaiyiOLS' 8t' rjv S' alriav, e'iprjraL /cat Trporepov, 
alfia fiev yap e;\;€tv rot? ivalfioLs SrjXov cLs dvay- 
KOioVf vypov 8' ovTos Tov at/xaros" dvay/catov dy- 
yetop- VTrapx^LV, i(f)^ o Sr] /cat (haiverai fjLepLrjxavrjadai 
TOLS <j)\e^as Tj (fiVGLS' o.pxy]V 8e tovtojv dvayKOLOV 

1^ etvat jLttav (ottov yap eVSe;(€Tat, filav ^iXriov r) 
77-oAAds"), r^ 8e Kaphia rchv cfyXe^cov apxT^' <f)aivovrai 
yap e/c ravTrjg ovaaL^ ko.l ov Std ravrr]?, /cat t] 
(f)VOLS avTTJg (f)Xe^coSr)s d>s ofioyevovs ovaiqs. e;)(et 
he /cat 0] BioLS avrrjs dpxf'Krjv x^P^^' """^pt [leaov 
yap, fiaXXov 8' ev roi dya» t^ Karco /cat efiTrpoadev tj 

20 OTTiodev iv TOLS ydp TLpaajTepois to TLjJLicjTepov 
KadlSpVKev 7] (j)VGLg, ov /xrj rt /ccoAuet /xet^ov. e/x- 
<f>av€GTaTOV 8e to XexOev ioTLV eirl tcjv dvdpw- 
TTOJv, jSouAerat 8e /cat ev rots' d'AAot? o/xoAdycos" ev 
jjLeao) Kelodai tov dvayKaiov aoj/xaros", rodrou 8e 
iripas fi Ta TrepLTTWfjLaTa d-Tro/cptVerat* rd 8e /cdiAa 

26 iT€(f)VKev dAAot? dAAto?, /cat ou/c eart tcov Trpog 
TO l^rjv dvayKaicoVy 8td /cat d<j>aipovfxevcjJv t^cooiv 
hrjXov 8* CO? oi}8e TrpoGTidefxeva (jideipeL. 

01 8* ev r^ K€(f)aXfj XiyovTes T-qv dpx^v tcov 
(fiXc^ojv ovK opOojs VTTcXa^ov. rrpcJJTOV fxev ydp 
TToXXds dpxds /cat SiCGTraafJievas^ ttoiovglv, efr' ev 

^ Lovaai Z. - 8i€a7Tapfi€vas ESUYZ. 

• The first observer after Aristotle to realize the disparity 
in the relative sizes of- the parts with time was Leonardo da 
Vinci (a.d. 1452-1518). 


proportion" : this is because the nature of the material 
and its bulk are especially obvious at the first stage 
of a creature's formation. The heart is present in 
all blooded animals, and the reason for this has been 
already stated : It is obviously necessary for all 
blooded creatures to have blood, and as blood is a 
fluid, there must of necessity be a vessel to hold 
it, and it is evidently for this purpose that Nature 
has contrived the blood-vessels. And these blood- 
vessels must have a source — one source (one is 
always better than many where it is possible), and 
this source is the heart. This is certain, because the 
blood-vessels come out of the heart and do not pass 
through it ; and again, the heart is homogeneous and 
in character identical with the blood-vessels. Further- 
more, the place in which it is set is the place of 
primacy and governance. It is in a central position, 
and rather in the upper part of the body than the 
lower, and in front rather than at the back ; Nature 
always gives the more honourable place to the more 
honourable part, unless something more important 
prevents it. WTiat I have just said is seen most 
clearly in the case of man, yet in other animals the 
heart tends in a similar way to be in the centre of 
the " necessary body," i.e. the portion of it which 
is terminated by the vent where the residues are 
discharged. The limbs vary in the various animals, 
and cannot be reckoned among the parts that are 
*' necessary " for life, which is why animals can lose 
them and still remain alive ; and obviously they could 
have limbs added to them without being killed. 

Those who suppose that the source of the blood- 
vessels is in the head are wrong, because : (1) this 
involves holding that there are many sources, 



665 b ^ 

SO TOTTCp xjivxpo). h'qXol 8e hvupiyos OJV, 6 Se Trepl ttjv 

Kaphiav rovvavriov. wanep 8' eXex^'f], Sto, /xev ra)V 
aXXcov urrXdyxvoiiv hUxovuiv at (fjXej^es, Slol 8e rrjs 
Kaphlas 01) hiareivei i^Xeip' odev kol hrjXov ort, 
jiopLOV Kal O-px^ Tojv chXe^cov iorlv r] Kaphia. Koi 
TOUT* euAoyoJS" p-eoov yap to rrjs /capSta? iarl 
35 awfxa TTVKVov Kal KoZXov 'n€(j)VK6s, eVt Se TrXrjpes 

666 a atpLaros (Ls rcov (fjXejScov ivrevdev rjpyfjievajv, koZXov 

TTpOS TO (j)vXdGG€LV TTjV dpX^V TtJ? depfJLOTTjTO? . €V 

ravrr) yap piovrj tojv OTrXdyxvojv Kal rod aayfiaros 
6 atfjia avev (jiXe^ajv €gtl, tcov 8' dXXojv fiopLOJV 
€KaaTOV iv rat? cfyXerjAv e;(€t to at/xa. Kal tovt ev- 
Adycus"- efc ttjs Kaphias yap eVoxeTeueTat \_KaXf eh 
ras (jiXe^as, el? Se ttjv Kaphiav ovk dXXodev avTTj 
yap eoTLV dpx^ Kal TTrjyrj tou atfiaTos rj VTroSoxrj 
TTpoiTT]. Ik twv dvaTOfJLOJV 8e KaTaSrjXa fidXXov 

10 ravTa, Kal eK tojv yeveaeojv evOeujs yap eoTLV 
evaipLOS TTpojTT] yivopLevrj tcov pLopiajv dnavTajv. en 
8* at KLvrjaeis tcov rjSecov Kal tcov XvTTTjpcov Kal 
oXcos 7Tdo7]s alod^decos evTevOev dpxop.evai (jjal- 
vovTai Kal TTpOS TavTr]v TTepaivovoai. ovtoj S* ex^L 
Kal KaTCL TOV Ao'yov, d-px^v yap etvai 8et /xtav, ottou 

15 evSex^rat,' ev(f)vdoTaTos 8e tojv tottojv 6 jxeaos, ev 
yap TO jxeaov Kal ctti Trdv ecjyLKTOv ofxotcos "5 rrapa- 
ttXtjolcds. CTt 8' eTTel ovTe tcov dvaipicov ovdev 

^ Kal om. Z. 
** Or " traverse." The connotation of this term seems to vary. 


scattered about ; and (2) it involves placing them 
in a cold region (its intolerance of cold proves this). 
The region round the heart, on the other hand, is 
warm. And (3) as has been said already, the blood- 
vessels run all through " the other viscera, whereas 
none passes through the heart ; which clearly shows 
that the heart forms part of the blood-vessels and 
is their source. Which is reasonable enough ; since 
the centre of the heart is a body of dense and hollow 
structure, and this is full of blood ; it is hollow to 
form a receptacle for the blood ; dense to guard the 
source of heat ; and the store of blood is obviously 
there because that is the starting-point of the blood- 
vessels. In none other of the viscera and in no other 
part of the body is there blood and yet no blood- 
vessels ; in each of the other parts the blood is con- 
tained in blood-vessels. And this too is reasonable, 
as the blood is conveyed and conducted away from 
the heart into the blood-vessels, whereas none is 
thus conveyed into the heart from elsewhere, for the 
heart is itself the source and spring of the blood, or 
the first receptacle of it. All this, however, is more 
clearly brought out in Dissections and Formative 
Processes, where it is sho^n that the heart is the 
first of all the parts to be formed and has blood in it 
straightway. Further, all motions of sensation, in- 
cluding those produced by what is pleasant and pain- 
ful, undoubtedly begin in the heart and have their 
final ending there. This is in accord with reason ; 
since, wherever possible, there must be one source 
only ; and the best situation for that is the centre, 
because there is only one centre, and the centre is 
equally (or nearly equally) accessible from every 
direction. Again, as every bloodless part, and the 



666 a ^ 

aiaOr^TLKov ovt€ to alfia, SfjXov cos to npcoTOV €XOV 

ws eV dyyelu) S' e^ov dvayKalov ctvat rrjv dpx'rjv. 

Ov fj-ovov he Kara rov Xoyov ovtojs ^X^'-^ </)atVeTat, 

20 dXkd Kal Kara, rrjv aiodiioLV. iv yap rols iji^pvoLS 
€vdea)s y] Kaphia (jiaiverai Kivovp^evT] rcov fiopLCJV 
Kaddrrep el ^coov, cos dpx^ Ti]s (fivaecos rols evaipLOis 
ovaa. fjcaprvpLov Se rcov elprjiiivcov Kal to Trdai 
rols evaiyiois VTrdpx^LV avrrjv dvayKalov yap avrols 
€X€LV TTjv dpxr]v rod at/iaros". vnapx^i Se Kal to 

25 Tjirap Trdai rols ivalfioLS' dAA* ovOels dv d^iojoeiev 
avTO dpX'Tjv etvai ovre rod oXov acofj^aros ovre rov 
atjjLaros' Kelrai yap ovSaficbs rrpos dpxoeuSrj OecnVf 
€;^et 8' coGTrep dvrl^vyov iv rols iidXiur dirriKpi^a}* 
fievoLs rov aTrXrjva. en 8' VTToSoxrjv alp,aros ovk 

30 €X€i- iv eavro) KaOdnep rj Kaphta, aAA' cooirep ra 
XoLTTo, iv 0AejSt. en he reivei hi avrov ^Ae?/f, 8t** 
iKeivqs 8' ovhepiia' TTaocov yap rcov (pXe^cbv iK rrjs 
Kaphias at dpxoLt. iirel ovv dvayKT] [xev ddrepov 
rovrcov dpxrjv etvai, ix-q ion he to rjirap, dvdyKTj 
rrjv Kaphlav etvaL Kal rov alpLaros dpx'^^v. ro fxev 

85 ydp ^a>ov alodTqaei copiorai, aladrjnKov he rrpcorov 

ro IT poor ov evaipLov, roiovrov 8' r) Kaphia' Kal ydp 

666 b dpx^ rod atfiaros Kal evaLfiov Trpcorov. 

"EcTt 8' avrrjs ro aKpov o^v Kal orepecorepov, 
1 hi Th. : ii vulg. ; mox €Keivov EUYZ. 

• Cor primum v'lvens ultimum moriens : cf. De gen. an. 
741 b 15 ff., and Ebstein & al., Mitt. z. Gesch. der Medizin u, 
Naturw., 1920, 19, 102, 219, 305. * See 655 b 29, n. 



blood itself as well, is without sensation, it is clear 
that the part where the blood is present first, and 
which holds it as in a receptacle, must of necessity be 
the source. 

This reasoning is supported by the evidence of 
the senses. In embryos, as soon as they are formed, 
the heart can be seen moving before any of the 
other parts, just like a living creature <* ; which 
shows that it is the source of their nature in all 
blooded animals. Another piece of evidence to 
support this is that all blooded creatures have a 
heart : why ? because they are bound to have a 
source for their blood. All blooded creatures, it is 
true, have a liver too ; but no one would care to 
maintain that the liver is the source either of the 
blood or of the whole body, because it is nowhere near 
the place of primacy and governance, and, also, in 
the most highly finished ^ animals it has something 
to counterbalance it, as it were, viz. the spleen. 
Again, the liver has no receptacle for blood in itself 
as the heart has : like the rest of the viscera, it keeps 
its blood in a blood-vessel. Again, a blood-vessel 
runs all through it, whereas no blood-vessel runs 
through the heart : all blood-vessels have their source 
from the heart and begin there. Since, therefore, of 
necessity the source must be one of these two, the 
heart or the liver, and as it is not the liver, it must of 
necessity be the heart which is the source of the blood 
just as it is of the rest. An animal is defined by the 
fact that it possesses sensation : and the part of the 
body to have sensation first is the part that has blood 
in it first — in other words, the heart, which is the 
source of the blood and the first part to have it. 

The apex of the heart is sharp and more solid than 



666 b 

Kelrai 8e rrpos ra> orqdei /cat oAoj? eV roZg npoodev 
rod GOJiiaros vpos to firj Karaifw^^odai avro' Trdai 
6 yap daapKorepov to GT7]do?, to. he vpavrj aap/coj- 
heoTepa, Sto rroWr^v e;(et GKeTTrjv to depf-iov /card 
TOP' vcoTOP'. ecTTt 8' 7'^ Kaphia toZs li€V aAAoi? l>cx)ois 

KaTOL piioOV TOV GTiqBlKod TOTTOV, Tols S' avB pOJTTOlS 

fjLLKpov els TO, evojvvjxa TrapeKKXivovaa irpos to 
aviGovv TTjv KaTonjjv^iv Tcov dpLGTepcbv fjidXiGTa yap 

10 TCOV dXXcov ^ipcx)v dvOpcoTTos ex^t KaTei/jvyp^eva tol 
dpiGTepd. OTL 8e /cat ev toIs Ix^vglv 6[jlolcjs rj 
Kaphia KeiTai, TvpoTepov etprjTai, /cat Stort (fyaiveTai 
avopLoioJS. ex^i he rrpos ttjv Ke(f)aXr]v to o^v' €GTt 
8' auTT^ TO TrpoGdev, eVt TavTiqv yap rj kIvtjgl?. 
"E;Yet he /cat vevpojv TrXrjOog rj Kaphia, /cat tout* 

15 evXoycos' 0,770 TavTrjs yap at KivrjGeLS, TTepaivovTat 
he hid TOV eA/cetF /cat dvteVat- 8et ovv TOLavT7]c 
VTTTjpeGLas /cat LGXvog. rj he Kaphia, KaOdnep 
€L7TO[j,ev /cat rrpoTepoVy olov t,(x}6v tl 7Te(j)VKev ev 
rols exovGLV. 

*'EorTt 8* dvoCTTeos" TrdvTOJV OGa /cat rj/JLels Teded- 
ixeda, TrXrjV tcdv lttttcov /cat yevovg tlvos ^ocJov 

20 TOUTOi? he hid TO jjieyedog otov epeLGfiaTOS X^P^^ 

OGTOVV VTTeGTl, KaddlVep /cat TOt? oAot? GWfiaGLV. 

KotAta? 8' exovGLV at pcev tcqv fieydXojv t,ipcov 
TpeZs, 0.1 he TCOV eXaGGovcov hvo, [xlav he Traoat* 8t* 
T]v 8' aiTLav, e'iprjTaL. hel ydp elvac tottov TLvd tt^s 

• At Be respir. 478 b 3. And see the next note. 

^ Instead of towards the breast. The meaning of this 
passage is made clear by Hist. An. 507 a 2 ff . In all animals, 
says Aristotle, the " apex " of the heart points forwards, and 
in most animals " forwards " is towards the breast. Fishes 


the rest, and it lies towards the breast, and altogether 
in the fore part of the body so as to prevent it from 
getting cooled : for in all animals the breast has com- 
paratively little flesh on it, while the back is well 
supplied and so gives the heat of the body ample 
protection on that side. In animals other than man 
the heart is in the centre of the region of the breast ; 
in man it inclines slightly to the left side so as to 
counteract the cooling there, for in man the left side 
is much colder than in other creatures. I have 
said already that the placing of the heart is the 
same in fishes as in other animals, though it appears 
to be different, together ^^'ith the reasons" for the 
apparent difference. In fishes its apex is turned to- 
wards the head ^ ; but in them the head is " forwards," 
because the head is in the line of direction in which 
they move. 

The heart has in it an abundance of sinews, which 
is reasonable enough, as the motions of the body have 
their origin there ; and as these are performed by 
contraction and relaxation, the heart needs the sinews 
to serve it and to give it strength. We have said 
already that the heart is like a living creature inside 
the body that contains it. 

In all cases that we have examined the heart is 
boneless, except in horses and a certain kind of ox. 
In these, owing to its great size, the heart has a bone 
for a support, just as the whole body is supported 
by bones. 

In the large animals, the heart has three cavities, in 
the smaller ones, two only ; and in no species has it less 
than one. The reason for this has been given : there 

appear to be an exception to this rule, but only because in 
them " forwards " is towards the head. 



666 b 

KapSiag /cat viroSox^jv tov irpojrov aijJLaro?. [on 

25 Se TTpojTOV iv TTJ /capSto, yiverai ro alfia, ttoXXolkls 
elpijKafjLev.) Std 8e^ to tcls dp)(r)yovs cfyXe^as hvo 
elvai, r-qv re [xeydXriv KaXovfievqv Kal rrjv doprii^v, 
€KaT€pas S'^ ovdYjg dipxrj? tojv ^Ae/Scov, Kal Sta- 
<f)opds e)(ovacx)v, Trepl cov vorepov ipovfiev, jilXriov 
Kal rds dpxcis avTcov /ce;^copta^af tovto 8' dv etrj 

30 8i(f)vovs ovTOs rod atfxaros Kal /<:e;\;6opto'ju,evoi>. 
SioTTep iv ots" evhex^rat, Su' €lgIv u7ToSo;^at. €V- 
Se^eraL S* iv rols /xeyciAot?* rovrojv yap €)(ov(n /cat 
at /capStat [xeyeOog. en Se jSeArtov rpet? etvat ra? 
/cotAta?, 07760? 77 /xta ap;;^?] /cotvr^* to 8e /JLeaov /cat 
nepLTTov dpx^' cocttc [xcyeOovs 8et fiel^ovos avralg 

35 aet, hiOTTep at ixiyLorai rpels exovau fiovai. 

667 a TouTCOv 8e TrAetCTTOv ju-ev af/xa /cat BeppLorarov 

exovGLV at 8eftat (Sto /cat tcuf pepojv depjjLorepa to. 
Sefta), iXdxi'f^TOV Se Kal ijjvxpdrepov al dpiGTepai, 
ixioov 8* at jLteo-at toj rrXriOei /cat depporrjTLy KaOa- 
pwrarov Se* 8et yap ti^v '^PXW ^'^^ fxdXior ripep^elv, 
6 TOiavrr] 8' ay etT7 KaOapov rod aifxarog ovrog, rep 
TTXr^dei he Kal deppLonqri [xeaov. 

*'E;!^oi>CTt 8e /cat hidpOpcouiv riva at /cap8tat napa- 

7rXr)OLav Tats" pat^alg. ovk elal Se Gvva(f)€.l? co? 

Ttvo? e/c TT-Aetovojv avvderov, dAAct Kaddnep etTTo/xev, 

hiapOpajoet pdXXov. elal 8e tcDv )Ltev aladrjTLKcov 

10 dpOpojBeGTepaL, tojv 8e vcoOporepajv dvapOporepai, 

1 8ta 86 ESUYZ : 8ia vulff. 
' S' Peck : ydp vulg., om. Ogle. 


must be some place in the heart which will be a 
receptacle for the blood when first formed. (As we 
have stated several times, blood is first formed in 
the heart.) Now there are two chief blood-vessels, 
the so-called Great Blood-vessel, and the Aorta ; each 
of these is the source of other blood-vessels ; and 
the two differ from each other (this will be discussed 
later) ; hence it is better for them to have separate 
sources. This result can be obtained by having two 
separate supplies of blood, and thus we find two 
receptacles wherever this is possible, as in the larger 
animals ^vhich of course have large hearts. But it is 
better still to have three cavities, and then there is 
an odd one in the middle which can be a common 
source for the other two ; since, however, this requires 
the heart to be particularly large, only the very 
largest hearts have three cavities. 

Of these cavities it is the right-hand one which 
contains the most blood and the hottest (that is why 
the right side of the body is hotter than the left) ; 
the left-hand cavity contains least blood, and it is 
colder. The blood in the middle cavity is inter- 
mediate both in amount and heat, although it is the 
purest of them all ; this is because the source must 
remain as calm as possible, and this is secured when 
the blood is pure, and intermediate in its amount and 

The heart has also a sort of articulation, which 
resembles the sutures of the skull. By this I do not 
mean to say that the heart is a composite thing, 
consisting of several parts joined together, but an 
articulated whole, as I said. This articulation is more 
distinct in animals whose sensation is keen, and less 
distinct in the duller ones, such as swine. There are 



667 a 

KaOdirep at rtDr vchv. at he hi,a(j>opai rrjs KapSlag 
Kara jjLeyedo'^ re kol ixiKpoTiqTa Kal GKX'qporrjrd re 
/cat fiaXaKOTTjTa t€lvovol rrrj kol Trpos to. tiOt]' to. 
fiev yap dvaLuOrjra GKXrjpdv €-)(€.l rriv Kaphiav kol 

15 TTVKvqVy rd 5' aloOiqriKd fiaXaKCorepaVy Kal rd pikv 
IxeydXas €)(ovra rd? KapSla? SeiXd, rd 8' iXdaaovs 
Kal jieGas OappaXewrepa (to ydp GvjJL^aiVov rrdOos 
VTTO rod (jyo^eZoBai TrpouVap^^et rourots' Sta to pir] 
dvdXoyov €)(^eLV rd Beppov rfj Kaphia, puKpdv 8' ov 
iv peydXoig dpavpovoOai, Kal rd alpa i/jvxpdrepov 

20 etvat) . pieydXas Se Ta? Kaphiag exovGL Xaycog, 
€Xa(f)os, /XL'S", vaLva, ovos, rrdphaXis ^ yaXrj, Kal 
TaAAa o-)(^e'd6v Trdvd^ dua <j)av€p(x)s 8etAd t) 8ta 
(f)d^ov KaKovpya. 

HapaTTXrjGuo? Se Kal inl ra>v ^Ae^cDv Kal eirl 
rwv kolXlojv ex^t' ipuxpal ydp at peydXai (f)Xej3€S 

25 Kal KOiXiai. coGTTep ydp ev piKpco Kal eV peydXcp 
olK-qpLan rd lgov TTvp rJGGOv ev rols peit^oGi 6ep- 
paivei, ovroj Kav rovrois rd Oepfxov dyy eta ydp 
Kal Tj (J)Xeifj Kal rj KoiXia. en 8' at dAAoTptat /ctvyy- 
Geis eKaGrov rojv deppLoJv KaraijjvxovGLV , ev 8e Tats" 
evpvxojpeGrepai? rd nvevpa rrXeZov Kal evLGxdei 

30 /xaAAov Std rcov pieyaXoKoiXiojv ovhev ovhe rcov 
pLeyaXofjiXe^ajv ttlov eGri Kard GapKa, dAAct ndvra 
7] ra TrXeiGra rcov roLovrcov dSrjX6(f)Xe^a Kal puKpo- 
KoiXia (jiaiverai. 

Mdvov he rojv GnXdyxvcov Kal oXws rcov iv rep 

' TrapSaAts] SopKaXis Piatt. 


other differences in the heart ; some hearts are large, 
some small, some are hard, some soft ; and these 
tend by some means to influence the creature's 
temperament. Illustrations of this are : animals 
whose powers of sensation are small have hearts that 
are hard and dense, those whose sensation is keen 
have softer ones ; and those with large hearts are 
cowardly, those with small or moderate-sized ones, 
courageous (this is because in the former class the 
affection which is normally produced by fear is 
present to begin M'ith," as their heat is not proportion- 
ate to the size of their heart, but is small and there- 
fore hardly noticeable in the enormous space that it 
occupies ; so that their blood is comparatively cold). 
The following creatures have large hearts : the hare, 
the deer, the mouse, the hyena, the ass, the leopard, 
the marten, and practically all other animals M'hose 
cowardice is either outright or else betrayed by their 
mischievous behaviour. 

Similar conditions obtain in the blood-vessels and 
the cavities of the heart : if they are large, they are 
cold. The effect of the same-sized fire is less in a 
large room than in a small one ; and the same applies 
to the heat in these receptacles, the blood-vessels and 
the cavities. Further, extraneous motions have a 
cooling effect upon hot things ; and the more roomy 
a receptacle is, the greater the amount of air (or 
pncuma) in it and the stronger its effect. Thus we 
find that no animal which has large cavities or large 
blood-vessels has fat flesh, and conversely, that all (or 
most) fat animals have indistinguishable blood-vessels 
and small cavities. 

The heart is the only one of the viscera — indeed 

« Cf. 650 b 27. See also 692 a 20. 



667 a 

craj/xart [lopicov tj Kaphia ;!^aAe7r6v TraQos ovhev 

i)7TO(f)ep€i, KOI Tovr evXoyoJS' <f)deLpofJL€V7]s yap rrjs 

35 dpx'^^ ^^^ eoTiv i^ ov yeVotr' dv ^oiqdeia rols 

667 b ciAAots" €.K Tavrr]s rjprr)iJLevoL£. arjiielov Se rov 

{jLTjOcv iTTihex^ordat, Trddos rrjv Kaphiav ro ev [irjhevl 

rcov dvopLGVCov Upetcov dx^Oai tolovtov irados irepl 

avTTjv woTT€p €7tI tcov dXXojv CTTrAayp^vcov. OL T€ 

yap V€<^pol TToXXaKLs ^aivovrai Xid(jov ficGTol /cat 

6 (fyvfidrcov /cat SoOc-qvajv /cat to rjTTap, (hoavTOJs Se 

/cat o TrXevjiajv, fidXiura 8' o anX-qv. iroXXd Se /cat 

€T€pa TTaOrjfjLara avfi^aLvovTa Trepl avrd ^atVerat, 

rJKLGra 8e rov [lev TrXevfiovos nepl rrjv dpTrjplav, 

rod 8' rJTTaros irepl rrjv GvvaipLV rfj fieydXr) (f)X€pL, 

10 /cat rovr evXoyoJS- ravrr) yap pidXiora kolvcovovgl 

ttJ /ca/)8ta. oca 8e 8ta voaov /cat roiavra TrdOrj 

^atVcrat TeAcurajvra rojv ^cocov, rovrois dvare/jLvo- 

fievoLS ^atVerat 77ept t7]v Kaphiav voawhiq Trddr). 

Kat Trepl [lev ttJ? /capSta?, 770ta rt?, /cat tlvos 
€V€K€V Kat 8td TtV atTtW vTrdpx^i' tols exovGLVf 
TOGavT elprjudco. 
1^ V. 'ETTOjLtevov 8* dv etrj Trepl rCbv (f)Xe^ojv eLTrelv, 
rrj? re fieydXrjs /cat rrjs doprrjs' avrai yap e/c tt^? 
Kaphias TTpojrai Sexovrat ro at/xa, at 8e AotTiat 
TOUTOJV d7ro(f)vdS€9 eloiv. ort //ev ow rod atjxaros 
xdpi'V etcTt, TTporepov eiprjrai' ro re yap vypov dirav 
20 dyyeiov 8etTat, /cat ro <j)Xepu)v yevos dyyetov, to 3* 


the only part in the whole body — which cannot 
withstand any serious affection. This is readily 
understood : the other parts depend upon the heart, 
and when this source itself is ailing, there is no place 
whence they can obtain succour. A proof that the 
heart cannot put up with any affection is this : Never 
has the heart in a sacrificial victim been observed 
to be affected in the way that the other viscera 
sometimes are. Very often the kidneys are found 
to be full of stones, growths, and small abscesses ; 
so is the liver, and the lung, and especially the 
spleen. Many other affections are observed in 
these organs ; but in the lung they occur least 
often in that portion which is nearest the Mindpipe, 
and in the liver in that portion which is nearest its 
junction with the Great Blood-vessel. This is readily 
understood : those are the places where they are 
most closely in communication with the heart. 
Those animals, however, which die as the result 
of disease, and affections such as I have mentioned, 
when cut open are seen to have diseased affections 
of the heart. 

We have now spoken of the heart : we have said 
what its nature is, what purpose it serves, and why it 
is present ; and that will suffice. 

V. I suppose that the next subject for us to discuss Blood- 
is the Blood-vessels, that is, the Great Blood-vessel ^^^^® ^' 
and the Aorta. It is these into which the blood 
goes first after it leaves the heart, and the other 
blood-vessels are merely branches from these. We 
have already said that these blood-vessels are present 
for the sake of the blood : fluid substances always 
need a receptacle, and the blood-vessels generally 
are the receptacles which hold the blood. We may 



687 b 

af/xa €V ravrais' Slotl 8e 8vo Kal oltto fxids oipxV^ 
Kad* arrav to aoj/xa SiareivovGL, Xeyojfxev. 

Tov fxev ovv els filav dpx'f)^ avvreXelv /cat oltto 

fJLids aLTLOV TO jLtlW €)(€LV TTOLVTa rTjv alad'qTLKrjv 

i/jvx^v ivcpyela, coare Kal to jjLopLov ev to TavTTjv 
€xov TTpojTOJS (eV pikv Tols evaip,ois /caret hrjvap.iv 

25 /cat /car' ivepyecav, twv S' avaipuDV ivlois /car' 
evepyecav p,6vov)y 8to /cat ttjv tov deppLou apx'rjv 
dvayKaXov iv to) avTco tottco elvai- avTT] S' IotIv 
atria /cat to) atjitart tt^s" vypoTTjTos /cat rT^S" ^ep- 
pLOTTjTOS' hid pukv ovv TO iv ivl etvai pLoplcp ttjv 
alG9r]TiK7jv dpx^v Kal tyjv ttjs 6eppi6T7)T0S Kal tj 

80 TOV atjLtaros" dno puds idTiv dpxrjs, hud he ttjv tov 
atpLaTos ivoTTjTa Kal rj rcDv (fyXe^cov aTTO pads. 

Ai;o S' etVt Sta to to, croj/xara etv^at hipLeprj tcov 
ivalpLCDv Kal TropevTLKOJV' iv Trdui yap tovtols 
Stco/Dtarat to eprrpoodev Kal to oTTioOev Kal to 
he^Lov Kal TO dpLGTepov Kal to dvco Kal to /cara>. 

35 oact) he TipnojTepov Kal rjyepLoviKWTepov to epu- 
868 a vpoadev tov oTTiodev, tooovto) Kal rj pieydXrj (fiXeifj 
TTJs dopTTJs' rj pLev ydp iv tols epLTrpooOev, rj 8' iv 
Tols OTTiodev KeiTaiy Kal ttjv p,ev dnavT^ e;)^et ra 
evaip^a ^avepcos, Trjv 8* eVta p^ev dpivhpojs evia 8' 

Tov 8' els TO TTdv hiahehouOai to cjcopia Tas 

6 (fyXe^as a'lTiov to navTOS elvai tov aco/xaros" vXrjv 

TO at/xa, Tots" 8' dvaipiois to dvdXoyoVy raura 8' iv 

* And potentially many ; cf. 682 a 4 ff . 



now go on to explain why there are two of these blood- 
vessels, why they begin from a single source, and why 
they extend all over the body. 

The reason why finally they both coincide in one 
source and also begin from one source is this. The 
sensory Soul is, in all animals, one actually ; there- 
fore the part which primarily contains this Soul is 
also one (one potentially as well as actually in the 
blooded animals, but in some of the bloodless animals 
it is only actually one °), and for this reason the source 
of heat also must of necessity be in the selfsame 
place. But this concerns the blood, for this source 
is the cause of the blood's heat and fluidity. Thus 
we see that because the source of sensation and the 
source of heat are in one and the same part, the blood 
must originate from one source too ; and because 
there is this one origin of the blood, the blood-vessels 
also must originate from one source. 

The blood-vessels are, however, two in number, be- 
cause the bodies of the blooded creatures that move 
about are bilateral : we can distinguish in all of 
them front and back, right and left, upper and lower. 
And just as the fore part is more honourable and 
more suited to rule than the back part, so is the Great 
Blood-vessel pre-eminent over the Aorta. The Great 
Blood-vessel lies in front, while the Aorta is at the 
back. All blooded creatures have a Great Blood- 
vessel, plainly visible ; but in some of them the Aorta 
is indistinct and in others it cannot be detected. 

The reason why the blood-vessels are distributed 
all over the body is that blood (and in bloodless 
creatures, its counterpart) is the material out of 
which the whole body is constructed, and blood- 
vessels (and their counterparts) are the channels in 



668 3 

(f)X€^l Kal TO) avaXoyov Ketadai. ttcos" /xev ovv 
Tpe(f)€Tai ra ^a)a koL €K rivos Kal riva rpoTTOv 
dvaXafi^dvovcnv ck rrjs KOiXlas iv tols Trepl yeve- 
crecD? Aoyots" fJ^dXXov dpfJiol^eL GKorreZv Kal Aeyetv. 

10 [EvviGrafjievcov Se rcov pLoplcov eV rod at/xaro?, 
Kaddirep eiTTOfiev, evXoycns r) rcov ^Ae/3ctjv puat? 
Std TTavTog rod awfiaros 7re(f)VK€V' Set yap Kal ro 
atfJLa Slcl TTavTos Kal irapd Trdv etvai, elnep rdJv jxo- 
picov eKauTOV eV rovrov Gwear-qKev^ 

"EotKe 8' ojOTTep €v re rols ki^ttols at vSpaycoylai 

IT' KaraoKevdljOVT at drro puds dpx^js Kal Trrjyrjg et? 
TToXXous 6x€rov? Kal dXXov? del irpos to Travrrj 
pLeraSiSovaL, Kal iv rat? OLKohopiiais irapd ndaav 
TTjv rcov depLeXiojv VTToypa^riv Xidoi Trapa^e^XrjvraL, 
Sid TO TO, pL€v Kr]7T€v6pL€va (jiveoOai eK rod vSaroSj, 
Tovs Se depLeXiovs eK rwv XtOcov olKohopLeiadai, rov 

20 avrov rpoirov Kal rj <^vgl? to atpia Std Travros 
wX^TevKe rod owpLaros, cVetST) navro? vXt] 7T€<f)VK€ 
Tovro. yiverai he KaTaSrjXov iv rols pLaXcara Kara- 
XeXeTTTvapiivois' ovOev yap dXXo (f)aLveTai irapd rds 
(j)Xe^ag, KaBdrrep iirl rdjv dpLTreXivajv re Kal avKivajv 

25 (f)vXXu)v Kal du dXXa roiavra' Kal ydp tovtojv 
avaivopievcov^ (fiXi^es XeiTTOvraL piovov. rovrcuv S* 
auTLov OTL TO afjLta Kal ro dvdXoyov rovrco Suva/xet 
aojpLa Kal odp^ t) ro dvdXoyov iariv KaOdirep ovv 

* 11. 10-13, quae praecedeiitia 1). 4-7 repetunt, secludenda. 
^ avau'Ofieicov attice Bekker. 

« This seems to be an unnecessary repetition of the last 
sentence but one. 


which this material is carried. As regards the 
manner in which animals are nourished, the source 
of the nourishment, and the processes by which 
they take it up from the stomach, it is more appro- 
priate to consider these subjects and to discuss them 
in the treatise on Generation. 

[But since the parts of the body are composed 
out of blood, as has been said, it is easy to see why 
the course of the blood-vessels passes throughout 
the whole body. The blood must be everywhere 
in the body and everywhere at hand if every one of 
the parts is constructed out of it.] ** 

The system of blood-vessels in the body may be 
compared to those water-courses which are con- 
structed in gardens : they start from one source, 
or spring, and branch off into numerous channels, 
and then into still more, and so on progressively, so 
as to carry a supply to every part of the garden. 
And again, when a house is being built, supplies of 
stones are placed all alongside the lines of the 
foundations. These things are done because (a) 
water is the material out of which the plants in the 
garden grow, and (6) stones are the material out of 
which the foundations are built. In the same way, 
Nature has provided for the irrigation of the whole 
body with blood, because blood is the material out 
of which it is all made. This becomes evident in 
cases of severe emaciation, when nothing is to be 
seen but the blood-vessels : just as the leaves of vines 
and fig-trees and similar plants, when they wither, 
leave behind nothing but the veins. The explana- 
tion of this is that the blood (or its counterpart) is, 
potentially, the body (that is, flesh — or its counter- 
part). Thus, just as in the irrigation system the 

I 251 


668 a 

iv rats ox^Teiais at jLteytarat rwv Td(f)pa)v 8ta- 
fXcvovGLV, at 8' eXd)(LGTa(, Trpwrai koI rax^ojg vtto 
TTJ? IXvo? d^avt^ovrat, ttolXlv S* iKXeiTTOvcrqs 
30 (jiavepal yivovrai, tov avrov rponov /cat tojv (jiXe^cbv 
at /xev jLteytcrrat hiafiivovuiv, at 8' iXd^^Lurai yi- 
vovrai udpK€s ivepyeca, Suya/xet 8' etatv ov8ev 
rJGGov (f)Xe^€s. 8 to /cat GCjL)l,o}xivcov rdv GapKwv 
Kad^ oTLovv alfia pel hiaLpovpievcjv' Kairoi dv€V pLev 
^Ae^o? ovK eGTLV at/xa, <f)Xe^iov^ 8' 07}8ev 87jAoy, 

35 COGTTep OvS^ €V ToZs OX^TOiS 0.1 Td<f)pOl TTplv "^ TrjV 

668 b tAuv i^aipeOrjvaL. 

'E/c /Ltet^ovcov 8' €t? e'AacrcroL'S' at ^Ae^e? aet 
TTpoipxovrai ea>? rou yeveGdai revs iropovs iXdG- 
Govg rrj? rod atf^iarog TTayrurrjros' 8t' ayv rep /xev 
alpLan SloSog ovk €Gri, ro) Se TTepirrcLpiari rrjs 
vypdg LKpidSog, ov KaXovpLev ISpcbra, /cat rovro 
5 StaOeppLavdevros rod GcopLaros Kal rajv (jyXe^iwv 
dvaGropLOjdevrcov. tJSt] 8e rtatv ISpojGaL Gvve^r] 
at/xarcoSet Trepirrwpiari 8td Ka^^^iav, rov pLev 
GcjpLaros pvdhos /cat pLavov yevopLevov, rod 8' at- 
pLaros i^vypavOevros 8t' d-n-eipLav, dSvvarovGTjs rrjs 
iv roZs (f^Xe^LOLs deppLorrjros Trecraetv 8t* oXLyorrjra. 
10 {etprjraL yap on rrdv ro koivov yrjs /cat vharos 
TTaxvv^Tat TveGGopLevov, rj 8e rpocfirj /cat ro alpLa 
pLiKrov i^ dp(f)OLV.) dSvvarel 8e neGGeiv rj deppLorrj? 
ov pLovov 8td r7]v avrrjs oXiyorrjra dXXd /cat 8id 
TrXrjdog /cat VTvep^oXrjV ri^s €lG<f>epopiiv7]s rpo<f)7Js' 
1 (^Ae/3tov Bekker. 

*• Could Aristotle have seen a case of haematoporphyria ? 


biggest channels persist whereas the smallest ones 
quickly get obliterated by the mud, though when 
the mud abates they reappear ; so in the body the 
largest blood-vessels persist, while the smallest ones 
become flesh in actuality, though potentially they 
are blood-vessels as much as ever before. Accordingly 
we find that, as long as the flesh is in a sound con- 
dition, wherever it is cut, blood will flow ; and 
although no blood-vessels are visible, they must be 
there (because we cannot have blood without blood- 
vessels) — just as the irrigating channels are there 
right enough, but are not visible until they are 
cleared of mud. 

The blood-vessels get progressively smaller as they 
go on until their channel is too small for the blood 
to pass through. But, although the blood cannot 
get through them, the residue of the fluid moisture, 
which we call sweat, can do so, and this happens when 
the body is thoroughly heated and the blood-vessels 
open wider at their mouths. In some cases, the sweat 
consists of a blood-like residue ° : this is due to a bad 
general condition, in which the body has become loose 
and flabby, and the blood watery owing to insufficient 
concoction, which in its turn is due to the weakness 
and scantiness of the heat in the small blood-vessels. 
(We have already said that all compounds of earth 
and water are thickened by concoction, and this cate- 
gory includes food and blood.) The heat may, as 
I say, be in itself too scanty to be able to cause 
concoction, or it may be that it is scanty in comparison 
with the amount of food that enters the body, if 

See A. E. Garrod, Itiborn Errors of Metabolism, Oxford, 1923, 
pp. 136 ff. Also H. Giinther, Deutsches Archiv /. klin. 
Medizin, 1920, 134, PP- 257 fF. 



668 b ^ 

yiverat 8e rrpos TavTr)v oXiyr]. r^ S' VTrep^oXrj 

15 SiCTG'q' Kal yap rep ttogo) /cat raj ttoico' ov yap ttov 
6pLoia>s evrrerrrov. [pel he fxaXiara ro aifia Kara 
rovs evpv)(cop^(yTOirovs rcov iropcov SiOTrep e/c rojv 
IJAJKrripojv Kal rcov ovXcvv Kal rrjs eSpas, eviore he 
Kal e/c rod orofiaros alfJLoppothes dnovoL yivovrai, 
Kal ov)(^ (jjcrnep e/c rrjg apriqpias p.era /Stas".) 

20 Atecrrojcrat 8* avcodev tj re p.eydXr] (^Xeip Kal rj 
doprrj, Kara) 3* evaAAacjcroL'crat (TVvexovGi ro aayp^a. 
TTpo'Covuai yap oxit^ovrai Kara rrjv Si^utav rcov 
KOjXajv, Kal T) fxev e'/c rod efiTrpoodev els rovmodev 
npoepx^rai, rj 8' e/c rod oinoOev els rovfXTTpoaOev, 

25 /cat GVfJi^dXXovaiv els ev warrep yap ev rots irXeKO- 
fievois eyyiverai ro Gvvexes [JidXXov, ovroj Kal Sta 
ri]s rd)V ^Xe^dov evaXXd^ews GwhelraL rd)V aojpid- 
rojv rd Trpoodia rols dmadev. ofiolajs he Kal dno 
rrjs Kaphias ev roXs dvoj ronois GVfi^alvei. ro he 
fjier dKpi^eias d)S exovaiv at (jjXe^es rrpos dXXiqXas, 

30 e/c re rojv dvaroficov Set OeujpeZv Kal e/c tt^s* ^ajLKrjs 
tar op las. 

Kat Trept piev <j)Xel3d)V Kal Kaphlas elp-qcdoj, 
rrepl he rd)v dXXajv urrXdyxyajv OKeTrreov Kara rrjv 
avrrjv fxeOohov. 

VI. UXevpLova pev ovv e;\;et 8ia ro nelov elval n 
yevos rd)V t,wajv. dvayKalov pev yap yiveodai ro) 

85 OeppLcp Kardipv^Lv, ravr-qs he heXrai OvpaOev rd 

669 a evaip^a rcov l^cLcov deppcorepa ydp. rd he /x?) eVat^a 

" The posterior rena cai'a. 
* Hist. An., especially 511 b 11—515 a 26. 



this is excessive ; and this excess may be due either 
to the quantity of it or (since some substances are 
less patient of concoction than others) to its quaUty. 
(Haemorrhage occurs most where the passages are 
widest, as from the nostrils, the gums and the 
fundament, and occasionally from the mouth. At 
these places it is not painful ; when, however, it 
occurs from the windpipe, it is violent.) 

The Great Blood-vessel " and the Aorta, which in 
the upper part are some distance from each other, 
lower down change sides, and thus hold the body 
compact. That is to say, when they reach the place 
where the legs diverge, they divide into two, and 
the Great Blood-vessel goes over to the back from 
the front, and the Aorta to the front from the back ; 
and thus they unite the body together, for this 
changing over of the blood-vessels binds together 
the front and the back of the body just as the cross- 
ing of the strands in plaiting or twining makes the 
material hold together more stoutly. A similar 
thing occurs in the upper part of the body, where 
the blood-vessels that lead from the heart are inter- 
changed. For an exact description of the relative 
disposition of the blood-vessels, the treatises on 
Anatomy and the Researches upon Animals ^ should be 

We have now finished our discussion of the heart 
and the blood-vessels, and we must go on to consider 
the remaining viscera on the same lines. 

VI. First the Lung. The reason why any group of Lung, 
animals possesses a lung is because they are land- 
creatures. It is necessary to have some means for 
cooling the heat of the body ; and blooded animals 
are so hot that this cooling must come from outside 



669a ^ ^ 

/cat Toj (7Vfi(f)vrco TTvevfJLarL Suvarat Kara\jjv')(€iv , 
dvdyKT] Se Karaipvx^LV e^cudev 7] vSari tj depi. 
SiOTTep Tijjv fiev l-)(9vojv ovheis ex^L TrXevfJiova, dXX* 
dvrl Tovrov ^pdyxLo., Kaddnep eipTirai ev tols irepl 
5 dva7TV0T]S' vSarc yap TTOLclrai ttjv Kardifjv^iv rd 
8* dvaiTveovTa rep dipt, hioirep Trdvra to, dva- 
TTviovra e;^€t TrXevpiOva. dvaTTvel Se rd fxev TTcl^d 
Trdvra, eVta 8e /cat rojv ivvSpojv, olov <j)d\aiva /cat 
heX(j>ls Kal rd dva(f)VGdjvra Kiqrri Trdvra' TToXXd ydp 

10 ra)V t)Cx)Oiv €TTayL(j)or€pit,€i rrjv cf)VGLVy Kal rdjv re 
TT€l,a)v /cat rdv dipa Sexofievcov Sta rrjv rov ocxijiaros 
KpdcTLV ev vypcp StareAet rov TrXeZorov xpovov, /cat 
rojv ev ro) vypcp p^erexei rooovrov evia rfjs 7Tel,rjs 
(f)VGeaj9 wor ev rep TTvevpLan avrcvv elvau ro reXos 
rov l^rjv. 

Tov 8* dvaTTvelv 6 vXevpLcov opyavov eon, rr)v fiev 

15 dpx'Tjv rrj? KLvrjaecos ex^JV dTTO rrjs /capSta?, ttoiwv 
8' evpvx<^pLav rfj elaoSco rov TTvevpiaros hid rrjv 
avrov GOfjicfyor-qra /cat ro fieyeOos' alpofxevov pev 
ydp elupeZ ro TTvevp,a, GvvLovros 8* e^epx^rau TrdXiv. 
ro 8e TTpos rrjv dXatv elvai rov vXevp,ova rrj? Kap- 
8tas' ovK eip-qrai /caAcos" ev dvdpajTTO) re ydp ovpt,- 

20 ^aivei puovov cos eiTreiv rd rijs Trrjhijaews 8ta to 
jjLovov ev eA7rt8t yiveaOai /cat TrpoohoKia rov p.eX- 
XovroSy dTTex^i r' ev rols TrXeiorois ttoXvv roTiov /cat 
Kelrai rrjv deoiv dvcorepoj rod TrXevpiovos, ojare 
p^TjSev ovp^dXXeodai rdv TrXevpova Trpds rrjv dXatv 
rrjs Kaphlas. 

Ata^epet 8' d TrXevfJiOiv ttoXv rotS" ^cools. rd fiev 

« See above, on 659 b 17. " 476 a 6. 

« See above, on 650 b 19 ff. 
*• This view is expressed by Timaeus in Plato's Timaeus, 70c. 


them, though the bloodless ones can do their own 
cooling by means of the connate pneuma.^ Now 
external cooling must be effected either by water or 
by air. This explains why none of the fishes has 
a lung. They are water-cooled, and instead of a 
lung they have gills (see the treatise on Respiration).^ 
Animals that breathe, on the other hand, are air- 
cooled, and so they all have a lung. All land-animals 
breathe ; so do some of the water-animals (e.g. the 
whale, the dolphin, and all the spouting cetacea). 
This is not surprising, for many animals are inter- 
mediate between the two : some that are land- 
animals and breathe spend most of their time in the 
water o^ving to the blend ^ in their bodies ; and 
some of the water-animals partake of the nature of 
land-animals to such an extent that the limiting 
condition of life for them Ues in their breath. 

Now the organ of breathing is the lung. It has 
its source of motion in the heart, and it affords a 
wide space for the breath to come into because it is 
large and spongy : when the lung rises up, the 
breath rushes in, and when it contracts the breath 
goes out again. The theory ^ that the lung is pro- 
vided as a cushion for the throbbings of the heart is 
not correct. This leaping of the heart is practically 
not found except in man, and that is because man is 
the only animal that has hope and expectation of 
the future. Besides, in most animals the heart is 
a long way off from the lung and lies well above 
it, and so the lung cannot be of any assistance in 
absorbing the throbbings of the heart. ^ 

There are many differences in the lung. Some 

* In quadrupeds the lung is above the heart, but not in 
man, owing to the difference of posture. 



25 yap evaijiov e;)(et kol /xeyav, ra 8' iXdrraj /cat 
aofi(f)6p, ra ^ikv ^cporoKa Std T')7v O^pixoTrjTa ttjs 
(pvGecos /xetjco /cat TToXvaifxov, ra 8' cooroKa ^rjpov 
/cat fjLLKpov, SwdfJievov 8e fJLeydXa Suaracrdai iv rw 
eix<f)vodo6 at, cjorrep rd rerpdiroha jJLev (horoKa Se 

30 Tojv Tret.ujv, olov 61 re oavpoi /cat at ;^eAajvat /cat 
77-ay TO TOiovrov yevos, ert 8e Trpos" rovrois r) rcov 
TTTrjvaJv (f)VGLS /cat KaXovfievojv opvidcov. TrdvTOJV 
yap TOVTOJV goijl<J)6s 6 TrAeu/xcov Kat ofiotos d(f)pa)' 
/cat yap 6 d(f)p6s e/c ttoXXov puKpog ytVerat Gvyx^o- 
/xevo?, /cat o rourcov rrXevpLCuv fiLKpog /cat viievcLSrjg. 

85 Sto /cat dSn/ja /cat oAtyoTrora ravra Trdvra, Kat 
Suvarat 77oAuy ev roi vypo) dve-x^eodai XP^^^^' ^'^^ 
yap oXiyov e^ovra Oepfiov iKavchs ^.ttl ttoXvv xpo^ov 

9 b Karaiffux^rai v-n avrrjs rrj? rod vXevfjiovos klvt]- 
aeojs, ovTos depojSovs /cat K€vov} 

(EvpLJSef^TjKe 8e /cat ra fieyeOi] toutojv iXdrroj rcov 
t,a)OJV ojs eTTLTTav etTretv to yap deppLov av^rjTLKOv, 
T) Se TToXvaipiia depfiorrjros orjfietov. CTt 8' opdoZ 
5 TO, Gdofiara /xaAAov, hioTrep dvdpojTTOs fJL€V rcJov 
aAAcov opdorarov, rd 8e ^ojoroKa rcJov dXXcvv rerpa- 
TToSwv ovSev ydp ofJLOLCog rpojyXoBvTel tcjv t,ojo- 


"OXoj? pLev ovv 6 TrXevpiCxJV icrrlv dvaTTVorjs X^P^^> 

dvaipios Se /cat TotoOTOS' yevovs rivos eVe/cev t,a)Cx)v' 

10 dAA' dvojvvpiov TO KOLvov Itt" avTOJV, /cat ovx U)G7r€p 

1 /:. 

ros . . . Keiov Thurot : ovcrqs ... Kcvrj^ vulg. 

« Cf. 653 a 30 ff. 



animals have a large lung, which contains blood ; 
others a small one and spongy. In the Vivipara it is 
large and has much blood in it because these creatures 
have a hot nature : in the Ovipara it is dry and small, 
but it can expand to a great size when inflated : 
examples of these are : among land -animals, the 
oviparous quadrupeds like the lizards, tortoises, and 
all such creatures, and in addition to these the 
tribe of winged things, the birds. All these have a 
spongy lung, which, like froth, runs together and 
contracts from a large volume into a small one. So 
it counts as small ; and also it is membranous. As a 
result, all these creatures are not much subject to 
thirst, and drink but little ; and also they can bear to 
remain a long time under the water : this is because 
their heat is scanty and can therefore be sufficiently 
cooled over a long period by the mere motion of the 
lung, which is void and air-like. 

(Consequently, one may add, in general these 
creatures are smaller in size than the majority of 
animals, as gro\\i:h is promoted by heat, and a plenti- 
ful supply of blood is a sign that heat is present. 
Furthermore, heat tends to make the body upright," 
which explains why man is the most upright among 
the animals and the Vivipara the most upright among 
the quadrupeds. And there are no viviparous 
creatures, either with or Avithout feet, so fond of 
creeping into holes as the Ovipara are.) 

The lung, then, is present for the sake of the 
breathing : this is its function always. Sometimes, 
to serve the purpose of a particular group, it is blood- 
less, and such as has been described above. There 
is no common name which is applied to all animals 
that have lungs. But there ought to be : because 

i2 259 


669b ^ ^ , , , , , y „ , 

O OpVLS (LvOfiaGTaL 6771 TLVOS yivOVS. StO a)CJ7T€p TO 

opviOi elvai €K TLVOS eCTTt, /cat e/cetVcoy cv rry ovcna 
vnapx^L TO rrXevfjLova ^x^iv. 

VII. Ao/cet 8e Ttoj^ cr7rAay;^v6ov to, jiev etvai 
ixovo^vi], KadoLTTep KapSca Kal vrAeu/xcuv, ret 8e 

15 SL(f)vrj, KadoLTTep ve(f)poL, tol 8' aTTopetrat TTOTepcus 
€X€i. ^aveit] yap av eTrajLt^orept^etv rourots' to 
fjTTap Kal 6 cttXt^v Kal yap chs iJLOvo(j)ves eKaTepov, 
Kal (Ls av6^ eVos" Svo TrapaTrXiqaiav exovTa ttjv 
<j>vaiv. eaTL 8e iravTa hi(j>vd. to 8' atTiov 77 tou 
awpiaTos StaoTaotS' SL(j)vr]s fxev ovaa, irpos /xtW 8e 

20 o-uyTeAoOo-a dpx'^v' to fiev yap avcx) Kal ko-toj, to 8* 
efiTTpoudev Kal oTnoBev, to 8e he^iov Kal apiGTepov 
ioTLV. hiOTTep Kal 6 iyK€(f)aXos jSouAerat St^ep^^S" 
etvat 77a(7t /cat rcDv alodrjTripiojv eKaoTOV. KaTO, 
Tov avTov 8e Adyov rj Kaphia Tals KoiXlats. 6 8e 
TrXevfJLCJV €V ye^ Tot? ojotokois togovtov SLeGTrjKev 

25 a>GT€ SoKeXv 8i;* ^X^*^^ auTo, irXevfiovas. ol 8e 
v€(f)pol Kal TTavTl brjXof /caTo, 8e to rJTrap Kal tov 
GTrXrjva SiKalajs av tls OLTTop'qGeLev. tovtov 8' 
atTtov OTt iv fikv toZs i^ dvdyK7]s exovGL GnXrjva 
Sdf €tev av otov vodov etvau rjirap 6 GirX-qVy iv Se toXs 
fjLTj i^ dvdyKr)5 exovGiv, aAAd TrdiipuKpov wGTrep 

30 Grjfjieiov X^P^^> evapycos Sifiepes to rjirdp eoTiv, Kal 
TO /Ltev {/Ltet^oyy els Ta Sefict, to 8' eAarrov etV Ta- 
piGTepd jSouAeTat ttjv deGLv ^x^lv. ov fxrjv oAAd /cat 
iv Tols woTOKOLS "^Jttov jjbev T) inl tovtojv <j)avep6vy 
iviois 8e [/cd/cet worrep ev Ttcrt]^ ^cootokols e77t8?]AaJS' 
hiiGTT)Kev , OLOV /caTct Ttva? TOTTOvs ol SaGVTToSes ^vo 

^ ye Peck : re vulg. ^ /xet^ov conieccram ; ma?or//ar5 S. 

' seclusi : woTrep ev riai cm. EY : Ka/cetVcov coni. Th. 


the possession of a lung is one of their essential 
characteristics, just as there are certain char- 
acteristics which are included in the essence of 
a " bird," the name which is applied to another such 

VII. Some of the viscera appear to be single why the 
{e.g. the heart and the lung) ; others double arrdoubie. 
{e.g. the kidneys) ; and some it is difficult to place 
under either heading. The liver and the spleen ap- 
parently are intermediate ; they can be considered 
either as each being a single organ, or else as two 
organs taking the place of one and having a similar 
character. In fact, however, all of them are double. 
And the reason for this is that the structure of the 
body is double, though its halves are combined under 
one source. We have upper and lower halves, front 
and back halves, right and left halves. Thus even the 
brain as well as each of the sense-organs tends in all 
animals to be double ; so does the heart — it has 
cavities. In the Ovipara the lung is so much divided 
that they appear to have two lungs. The kidneys 
are obviously double ; but there is fair room for 
hesitation about the liver and spleen. This is be- Liver and 
cause in those animals which of necessity have a "P^^®^ 
spleen, the spleen looks rather like a bastard liver, 
while in those which have a spleen though not of 
necessity — i.e. a very small one, as it were by way 
of a token — the liver is patently double, and the 
larger part of it tends to lie towards the right, the 
smaller towards the left. Still, there are cases even 
among the Ovipara where this division is less distinct 
than in those just described, while in some Vivipara 
the division is unmistakable — e.g. in some districts 



669 b ^ „ y „ , ^ y , H , 
35 hoKOvoiv rjTTar ^x^lv, Kaddnep rcbv IxOvcov erepoi 

re nves xal ol aeXaxcoSets. 

670 a Atd 8e TO TTjv deoiv €X^t,v TO rjTTap iv rois he^ioZ? 

jidWov 7] rod OTrXrjvos yeyove (f)VGiSy cjor* avay- 

KOLOV {lev 7TC05, fJLTj AtttV 8' €LVaL TTOiGL TOt? t,OJOlS > 

Tov i-iev ovv SL(f)vrj rr]v (f)VOLV etvai rcov OTrXdy- 
Xvcov atrioVy coGirep etTTOfjiev, ro Su' etvai ro Se^tov 
5 /cat ro dpiorepov eKarepov yap ^rjreZ ro ojioiov, 
wcnrep /cat a?3Ta ^ovXerai TrapairX'qGiav /cat hihvpir]v 
€X^Lv rrjv (j}-uoLVy /cat Kaddrrep^ e/cetva StSu/xa /xeV, 
avvqprrjrat 8' els eV, /cat rcov oirXdyxvcov ojjlolojs 

"EaTt 8e GTrXdyxvoL rd /cclto) rod vno^cofj-aro? 
KOLvfj fiev ndvra rcov ^Ae^cDv x^P^^* ottojs ovoai 

10 ixeriojpoL jLteVcoot toj rovrcov avvSeofJia) Trpos ro 
aojfjLa. Kaddnep dyKvpai yap ^eftXr^vrai rrpos ro 
(Tcofia 8td rcov dTTorerafiivijJv ixopiojv diro fxev rrj<; 
fxeydXr^s (f)X€^6s Trpos ro rjTTap Kal rov GTrXrjva, 
rovrojv yap rcov orrXdyxvo^v rj (J)vgls olov tjXol irpos 
ro GcojJLa TTpooXafi^dvovGLV avrrjv, els piev rd 

15 TrXdyia rod Gcofxaros ro 6^ rjirap /cat o gttXtjv rrjv 
<f)Xe^a rr]v fjLeydXrjv [dTTo ravrrjs yap els avrd pLovov 
hiareivovGL (fyXef^es), els 8e rd OTnodev ol ve(f)poL. 
Trpos 8* eKeivovs ov fiovov aTro rrjs pLeydXrjs 
(f)Xe^6s dXXd /cat aTTO r7]s doprrjs reivei (j)Xeip els 

TauTa St) ovp^aivei 8 id ro-urojv rfj GVoraGei 

20 rcjv l,a)OJV /cat ro jxev rjrrap /cat o gttXt^v ^orjOel 
TTpos rrjv TTeipLV rrjs rpocfyrjs (eVat/xa ydp ovra dep- 

^ KoX Kaddvep PZ : «ai om. vulg. 



hares appear to have a couple of livers ; so do certain 
fishes, especially the cartilaginous ones.* 

The spleen owes its existence to the liver being 
placed somewhat over to the right-hand side of the 
body : this makes the spleen a necessity in a way, 
though not an urgent one, for all animals. 

Thus, the reason why the viscera are double in 
their formation is, as we have said, that the body 
is two-sided, having right and left. Each of the two 
aims at similarity, just as the sides themselves strive 
to have a similar nature, and to be as like as twins ; 
and just as the sides, though dual, are conjoined 
together into a unity, so also it is with the several 

The viscera which are below the diaphragm are 
all of them present for the sake of the blood-vessels, 
in order that the latter may have freedom of carriage 
and at the same time be attached to the body by 
means of the viscera, which act as a bond. Indeed, 
there are, as it were, anchor-lines thrown out to 
the body through the extended parts : e.g. from the 
Great Blood-vessel to the liver and to the spleen, for 
these viscera act, as it were, like rivets and fasten it 
to the body ; that is to say, the liver and the spleen 
fasten the Great Blood-vessel to the sides of the body 
(since blood-vessels pass to them from it alone), while 
the kidneys fasten it to the rear parts. And to the 
kidneys — to each of them — there is a blood-vessel 
passing not only from the Great Blood-vessel but 
also from the Aorta. 

These advantages, then, accrue to the animal organ- 
ism from the lower viscera. Liver and spleen also 
assist in the concoction of the food, since they both 

« Sharks, etc. 



870a ^ ^ 

fXTjV €^€1 TTjV (f>VGLv), ol 8e V€(f)pOL 77/30? TO TTCpLT' 

TCUfia TO elg rr)v kvgtlv OLTTOKpLvofievov. 

KapSta fi€V ovv Kal r^Trap Trdoiv avayKoia rois 

fojot?, 7] fiev Sua Tr]v rrjs OepjxorT^ros o-p-xjiv (Set yap 

25 eivai TLva olov eoriav, iv fj KeloeraL rrjs (jivoecos to 

t,(JJ7TVpOVV, Kal TOVTO €V<f)vXaKTOV , a)G7T€p CLKpOTToXiS 

ovaa Tov Oixifxaros) , to 8' rjirap rrjs neipews x^tptv. 
TTOLvra 8e helrai ra eVat/xa hvolv tovtolv, hioTrep 
€X€L TTOLvra ra evaifia Suo Ta 07T\ay)(ya ravra^' oaa 
30 8' avarrveZ, Kal TrXevfjiova rpirov. 

*0 8e GTrXrjv Kara GvjJL^e^rjKos ef dvdyKrjs vtt- 
dpx^L roLS e^ovGLV, cjGTrep Kal ra Trepirrajpiara, 


€V TLGLV e/cAetVet KaTO, to piiy^Bos, ojGirep tojv T€ 

7TT€pa>Ta)v ivLOLS, OGa depjXTjv €;^et ttjv KoiXiav, olov 

670 b TTepiGTepd, Upa^, IktZvos, Kal irrl tcjv choTOKwv 

8e Kal TeTpaTToScov opLoicos (puKpov yap TrdjJiTTav 

exovGLv), Kal ttoXXoXs tojv XeTTiSajTcov drrep Kal 

KVGTLV ovK ex^L Slo, TO TpeTTeodaL TO TTepLTTajfia Slol 

fiavojv TOJV GapKcbv els TTTepd Kal XeirlSas. 6 yap 

5 GTrXrjv dvTLGTTO. CK Trjs KOLXias Tas LKfidSas tols 

TTCpLTTevovGas , Kal hvvaraL GVixireTTCLV alfiaTcoSrjs 

a>v. dv 8e to TreptTTCofia rrXelov fj t) oXiyoOepfios 6 

GTrX'qVy vooaKepd ylveraL jrXrjp-qs^ (ovGoy Tpocjiris' 

Kal 8ta TTjV ivTavda iraXippoLav ttjs vypoTrjTos ttoX- 

Aot? at KOLXiaL GKXrjpal yivovTaL GTrXrjvLWGLV, a)G- 

10 Trep TOLS Xiav ovprjTLKoZSi 8ta to avrLTTepLGTrdodaL 

* Tavra P : ravra fiovov vu\g. 

* nXi^pm EYZ : TrX-qfyi) vulg. 

^ {oSaa) Peck. 



have blood in them and so are hot. The kidneys 
assist in connexion with the residue which is excreted 
into the bladder. 

Now the heart and the liver are necessary to all 
animals. The heart is necessary because there must 
be a source of heat : there must be, as it were, a 
hearth, where that which kindles the whole organism 
shall reside ; and this part must be well guarded, 
being as it were the citadel of the body. The liver is 
necessary for the sake of effecting concoction. All 
blooded creatures must have these two viscera, and 
that is why these two are always present in them. 
A third, the lung, is present in those animals that 

But the spleen, where present, is present of necessity spleen. 
in the sense of being an incidental concomitant, as 
are the residues in the stomach and in the bladder. 
So in some animals the spleen is deficient in size, 
as in certain birds which have a hot stomach, e.g. 
the pigeon, the hawk, and the kite ; the same applies 
to the oviparous quadrupeds (all of these have an 
extremely small spleen) and to many of the scaly 
creatures. These animals just mentioned also lack 
a bladder, because their flesh is porous enough to 
enable the residues formed to pass through it and , 
produce feathers and scales. For the spleen draws 
off the residual humours from the stomach and in 
virtue of its blood-like nature can assist in the con- 
coction of them. If, however, the residue is too 
bulky or the spleen has too little heat, the stomach 
gets full of nourishment and becomes diseased. 
And in many cases, when the spleen is ailing, 
the stomach becomes hardened owing to the 
fluid which runs back into it. This happens with 



670b ^ ^ ^ 

rag vyporriras. olg Se oXiyi) TrepirrayoLS yiverai, 
Kaddirep roXg opvioLs koI tols Ixdvat, ra pikv ov 
fxeyav ex^L, ra 8e or^ixeiov ;)(aptv. /cat ev rots 
rerpoLTTOGi Se roTg (1)Ot6kols fiLKpo? Kal GTK^pos kol 
ve^poihrjs 6 gtt\i]v cutl 8ta ro rov TrXevjJLOva oofi^ov 

15 elvai KOI oXiyoTToreZv kol to Trepiyivoixevov Treplr- 
rcofJLa rpeTTeoOai els to crco/xa /cat ras (j)o\ihas, 
wavep etV ra rrrepa rols opvioiv. 

'Ev Se rot? KvcfTiv exovoi /cat tov TrXevjJLOva 
evaijJLOV vypog ian Sid re ttjv elpT^fJievqv alriav /cat 
Sta TO Tr]v (jyvGLV rrjv Toiv dpiorepayv oXcog vypo- 

20 repav elvai /cat i/jvxporepav. hir^p-qrai yap rcjv 
ivavTLOJV eKaorov npos rrjv uvyyevrj avaroLXtav, 
otov Se^iov ivavriov dpLOTepco /cat Oepf-iov evavrtov 
ipvxpcp' /cat GVGTOLXOL yoLp aAATJAot? eiVt rov elprj- 
fxevov rpoTTov. 

Ot Be vecfypol rots exovGLv ovk ef dvdyK-qg dXXd 
rod €V /cat /caAco? eVe/cev vrrdpxovGiv rrjs yap 

25 7T€pirr(xiGeojs X^P^^ "^V^ ^^'^ "^W f^^^^'^'-^ ddpoit,oii€vr]s 
eLGi Kara rrjv Ihiav cf)VGLV, iu ogols TxAetov vtto- 
arrjiJLa yiverai ro roiovrov, ottcos ^eXnov a7ro8t8a> 
Tj KVGns ro avrrjs epyov. 

*E77et Se rrjs avrrjs eVe/ca ;^/3etas' tous" re ve^povs 
GVfjL^e^TjKev e;^etv to, ^a>a /cat rr^v Kvoriv, XeKreov 

80 TTepl KVGretos vvv, vjrep^dvras rov ecfje^rjs raJv 
fMoplajv dpidfJLov TTepl yap (f)pevcov ovSev tto) 8t- 

" The reference to the " columns " or " double list " is 
not clear. There was a Pythagorean avaroixia; this and 
other avGTOLxlai are mentioned in Ross's note on his trans- 
lation of Met. 986 a 23. 

'' i.e. left and cold are both in the same column ; right and 
hot are both in the other column. 



tliose who make water excessively : the fluids are 
drawn back again into the stomach. But in animals 
where the amount of residue produced is small, as in 
birds and fishes, the spleen is either small or present 
simply by way of a token. In the oviparous quadru- 
peds, too, the spleen is small and compact, and 
like a kidney, because the lung is spongy and the 
animals drink little, and also because the residue 
which is produced is applied for the benefit of the 
body itself and of the scaly plates which cover it, 
just as in birds it is applied for the benefit of the 

In those animals, however, which possess a bladder, 
and whose lung contains blood, the spleen is watery. 
The reason already given partly explains this. An- 
other is that the left side of the body is generally 
more watery and colder than the right. As we know, 
the opposites are divided up into two columns," so 
that each is classed with those that are akin to it, e.g. 
right is in the opposite column to left, and hot to 
cold ; and thus some of them stand together in the 
same column, as I have just indicated.^ 

Kidneys are present in some animals, but not 
of necessity ; they are present to serve a good pur- 
pose ; that is to say, their particular nature enables 
them to cope with the residue which collects in the 
bladder, in those cases where this deposit is somewhat 
abundant, and to help the bladder to perform its 
function better. 

Since the bladder is present in animals to serve 
precisely the same purpose as the kidneys, we must 
now say something about it. This will involve a 
departure from the serial order in which the parts 
actually come, for we have said nothing so far about 



670 b 

copiorai, TOVTO 8e tl rcov irepl ret cr77-Aay;^va jxopioiv 

VIII. Kucrrtv 8* ov Travr* ex^i to. ^coa, dAA* 
eoiK€v Tj cf)VGLg ^ovXojxlvrj airohihovai rots e)(ovoi 

671 a Toy TrXevyiova evatfiov fiovov, rovroLS 8* evXoyojs. 

Sta yap rrjv vnepox'^v rrjs (f)vcr€a)?, rjv exovGLV iv 
Tip pLopioj TOVTcp, Sup-qriKa re ravr iorl /xaAtara 
rcjv t,(pojv, Kal Setrat rpo(j)y]s ov jjlovov rrjs i'^pds 
dXXa Kal TTJg vypds TrXelovos, cuctt' €^ avdyK7]s Kal 

; 5 TTeplrTcofia yiveodai nXelov Kal fjurj rooovrov fiovov 
oaov VTTO rrjs KOiXta? TrerrecrOaL Kal eKKpiveuSai 
fxerd Tov ravTrjs TTepirrajpLaros. dvdyKr) roivvv 
ctval ri ScKTiKov Kal rovrov rod TrepiTTcofiarog. 
SiOTTep ocra nXevfJiova e)(€i tolovtov, dnavr e;^et 
KVGTiv oaa he jjir^ tolovtov, dAA' rj oXiyoTTord eon 

10 hid TO TrXevfjiova e^^iv GOjJicfyov, rj oXcos ro vypov 
TTpOGcfydperaL ov ttotov X^P^'^ dXXd rpO(j)rJ9, otov rd 
evTOjJLa Kal ol IxOves, ert he Trrepcurd eoriv rj 
XeTTihoird t) ^oAtScord, ravra 8t' oXiyorrjrd re rrjs 
rod vypov rrpoocjyopds Kal hid rd rpeTreuBai els 
ravra rd TrepiyivopLevov rod TTepirriopiaros ovhev 

15 €X€i rovrojv Kvoriv, irXr^v at ;^eAcDp'at rcov ^oAtScu- 
TOJV, Kal ivravd^ rj (f)vais KeKoXo^corai jxovov atriov 
8' on at jiev OaXdrriai aapKcohrj Kal evaijiov exovoi 
rov TrXevjjLova Kal djxoiov rco ^oeico, at he ;)(epcratat 
jLtet^o) 7j /caret Xoyov. en he hid ro oorpaKajhes 

20 Kal TTVKVov elvai ro rrepiexov ov hianveovros rov 
vypov hid fjiavcov rojv aapKOJv, olov rois dpviai Kal 
roZs d(j)eai Kal rois dXXois rois <j)oXih(x}rois , vrro- 

PARTS OF ANIMALS, III. vii.-viii. 

the diaphragm, though this is one of the parts that 
are near the viscera. 

VIII. The bladder is not present in all animals : Bladder. 
Nature seems to have intended only those animals 
which have blood in their lung to have a bladder. 
And this is quite reasonable, when we remember that 
such animals have an excess of the natural substance 
which constitutes the lung, and are therefore more 
subject to thirst than any others ; i.e. they need a 
larger amount of fluid food as well as of the ordinary 
solid food, and the necessary result of this is that a 
larger amount of residue also is produced, too large 
in fact for all of it to be concocted by the stomach 
and excreted with its own proper residue ; hence it 
is necessary to have some part that will receive this 
additional residue. This shows us why all animals 
which have blood in their lung possess a bladder 
too. As for those whose lung is spongy and which 
therefore drink little, or which take fluids not as 
something to drink but as food (e.g. insects and 
fishes), or which are covered with feathers or scales 
or scaly plates, not one of these has a bladder, owing 
to the small amount of fluid which they take and 
owing to the fact that the surplus residue goes 
to form feathers or scales or scaly plates, as the 
particular case may be. Exceptions to this are the 
Tortoises : though scaly-plated they have a bladder. 
In them the natural formation has simply been 
stunted. The cause of this is that in the sea-varieties 
the lung is fleshy and contains blood, and is similar to 
the lung of the ox ; while in the land-varieties it is 
disproportionately large. And whereas in birds and 
snakes and the other scaly-plated creatures the 
moisture exhales through the porous flesh, in these it 



671 a 

CTTttCTt? ytverai roaavrrj ware SeladaL rrjv (f>v(JLV 
avTcav e\'etv rt fiopiov Scktckov Kal dyycLcvSeg. 
KvoTLv jiev ovv ravra fjiovov rwv roiovrcov e;)(et 8td 

25 TavT-qv TTjv alriav, rj fxev daXarria fjLeydXrjv, at Se 
X^pdatai fjLLKpdv Trdfirrav. 

IX. 'OjjLOLCos 8' ex^i Kal Tvepl vecjipcov. ovhe yap 
ve(f)povs ovT€ rcov TTrepwrcov /cat AeTrtSajrcDv ovhev 
€X€L ovT€ Tcov (^oXlSojtcov, ttXtjv at daXaTTcai 
X^XojvaL Kal at ;;^e/oo'atat • dAA* d)s rrjs et? rovs 

80 v€(f)pov9 Terayixivqs crapKos ovk ixovor^s ;^ojpav 
dAAct SLeGTTapfJLevrjs et? TroAAd, TrXaria ve(f)po€ih7J iv 
evLOLs TCOV opvidojv eariv. rj S* ifJivg ovt€ kvutlv 
ovT€ v€(f)povs ^X^^' ^^^ '^^ fJLaXaKorrjra yap rov 
X^XojVLOV evSLaTTvovv yiverai to vypov. r) pikv ovv 
Ijxvs hid TavTTjv rrjv atrtav ovk ex^t tojv fjLoplajv 
ovheTepov toIs S' dXXois ^ojots" toZs exovGLv ev- 

35 atfJioVy ajGTTep etpT^rat, tov TrXevfiova vrdat gvjjl- 

671 b ^€^r]K€v €X€LV v€(f)pov£. KaTaxpTjTai yap rj (f)vcns 

dfia TCOV re cfjXe^dJv X^P^^ '^^^^ Trpos ttjv tov 

vypov TTepiTTWjjLaTOS €KKpiGLV (f)6p€L ydp els 

avTovs TTopos eK TTJs fieydXrjs (fyXe^os. 

''E;;^ofcrt 8' ol vecppol TrdvTcg koIXov, t) TrXelov rj 
6 eXaTTOV, TrXrjv ol ttjs cfycoKrjs' ovtol 8* dpLOioi rots' 
^oeioL? 6vT€s GTepecoTaTOL irdvTOJV ecGLV. o^otot 8e 
Kal ol TOV dvdpciJTTOv Tols ^oeiois' €lgI ydp ajGirep 
GvyKetfxevoL Ik ttoXXcjv v€(f)pdjv fXiKpaJv Kal ovx 
djLtaAetS", a)G7T€p ol twv rrpo^dTCjov Kal tcov dXXcov 
TOJV reTpaTToScov. 8to Kal to dppcoGTTjfia toZs 

<• Greek, " hemys." This description, which does not fit 


cannot do so, because the integument which surrounds 
them is dense, hke a shell ; and so the excretion is 
produced in such quantities that the Tortoises need 
some part which shall act as a vessel to receive it. 
That, then, is why they are the only animals of the 
kind which have a bladder. In the sea-tortoise it is 
large, in the land-tortoise quite small. 

IX. Much the same may be said of the kidneys as Kidneyts. 
of the bladder. Kidneys are not present in any of 
the animals that have feathers or scales or scaly plates, 
except the two sorts of tortoises just mentioned. In 
some birds, how^ever, there are flat Iddney-shaped 
objects, as if the flesh that was allotted to form the 
kidneys had found no room for its proper function 
and had been scattered to form several organs. The 
Emys ^ has neither bladder nor kidneys : this is be- 
cause it has a soft shell which allows the moisture to 
transpire freely through it. But, as I said before, all 
the other animals whose lung contains blood have 
kidneys, since Nature makes use of them for two pur- 
poses : (1) to subserve the blood-vessels ; and (2) to 
excrete the fluid residue. (A channel leads into them 
from the Great Blood-vessel.) 

There is always a hollow (lumen), varying in size, 
in the kidneys, except in the seal, whose kidneys are 
more solid than any others and in shape resemble 
those of the ox. Human kidneys too resemble those 
of the ox : they are, as it were, made up out of a 
number of small kidneys,^ and have not an even 
surface like those of the sheep and other quadrupeds. 
Thus, when once an ailment attacks the human 

any animal now known as Emys, seems to be that of some 
freshwater tortoise. 

'' This is not true of the normal adult, but it is true of 
the foetus. 



671 b ^ ^ 

10 avdpcoTTOLs SvaanaXXaKTOV avrcov iariv, av dna^ 

voarjcrojGLV' avfi^atvei yap ojairep ttoXXovs v6(f)povs 
vooovvTixjv x^^XeTTOjrepav etvaL ttjv laaiv "q rcov eva 


'0 8' OLTTO Ti]5 (f)Xe^6£ reivojv iropos ovk et? to 
KolXov TcJuv v€(f)p(jijv KaTareXcvrd, dAA' el? to ocofxa 
KaravaXiuKeTai rwv v€(f)pa)V' hioirep ev rols kolXols 

15 avTOJv OVK iyyiverai alfMa, ovSe m^yvvrai reXev- 
TcLvTiov. eK 8e tov koLXov TCOV V€(f)pCOV cf)€pOVGL 
TTopoi dvai/jLOi et? ttjv kvgtlv hvo veaviKoi, i^ 
eKarepov ef?, Kal aAAot e/c ttjs doprijs laxvpol /cat 
avvexels. ravra 8* e;^et rov rponov rovrov ottojs 
eK fxev TTJs" ^Ae^os" to TreptTTCo/xa Trjs vypoTTjTO? 

20 ^ahitpr^ els tovs ve(f)povs, eK 8e rtuv ve(f)pcx)V rj 
yuvofievq virouTauis StrjOovfJievcDV tcov vypcov Bid 
tov (jcLpLaTos Tcbv ve(f)pa)v els to fxeaov avpperj^ ov 
TO KoZXov ol TrXeluToi exovGLV avTcov {Slo Kal Sva- 
coSeGTaTOV tovto tojv GTrXdyxvojv euTLv)' eK 8e tov 
fjieaov 8ta. tovtojv tojv TTopojv els ttjv kvgtlv tJSt] 

25 fJidXXov CVS TTepLTTajfjia dTTOKpiveTai. KaBojppiiGTai 
8' -q KVGTLS eK TOJV ve(f)pdjv' TeivovGi ydp, ojGirep 
eLprjTat, iropoi iGxvpol irpos avTiqv, 

01 fiev ovv vecjjpoi hid TavTas ras" atrta? etcrt, Kal 
ras" Svvdpieis exovGi ras" elprjfxevas. 

'Ev TTaGL 8e ToXs exovGL vecf)povs 6 Se^Los dvojTepco 
TOV dpiGTepov eGTLv 8ta ydp to ttjv klvtjglv elvaL 

80 eK TCOV Se^Lcov Kal iGxvpoTepav 8td raur' etvat ttjv 

• The ureters. 



kidneys, the trouble is not easily removed, because 
it is as though the patient had many kidneys diseased 
and not one only ; and so the cure is more difficult to 

The channel which runs from the Great Blood- 
vessel to the kidneys does not debouch into the 
hollow part of the kidneys, but the whole of what 
it supplies is spent upon the body of the kidneys ; 
thus no blood goes into the hollows, and at death 
none congeals there. From the hollow part of the 
kidneys two sturdy channels ** lead into the bladder, 
one from each ; these contain no blood. Other 
channels come from the Aorta to the kidneys ; 
these are strong, continuous ones. This arrange- 
ment is on purpose to enable the residue from the 
moisture to pass out of the blood-vessel into the 
kidneys, and so that when the fluid percolates 
through the body of the kidneys the excretion that 
results may collect into the middle of the kidneys, 
where the hollow is in most cases. (This explains, 
incidentally, why the kidney is the most ill-scented 
of all the viscera.) From the middle of the kidney 
the fluid is passed off through the aforesaid channels 
into the bladder ; by which time it has practically 
taken on the character of excremental residue. The 
bladder is actually moored to the kidneys : as has 
been stated, there are strong channels extending 
from them to it. 

We have now given the causes for which the 
kidneys exist, as well as their character and functions. 

The right kidney is always higher up than the left. 
The reason for this is that as motion always begins on 
the right-hand side, the parts that are on that side are 
stronger than those on the other ; and owing to this 



671 b ^ ^ ^ 

(j)VGiv TTjv rcbv 8e^ta>v, Set TrpooSoTTOLrjoaGdai Blol 

rr]v KLvrjGLV irpos ro avoj ravro} ra /xopta /xaAAov, 
eVet Kal rrjv o(f)pvv rrjv Seftav aipovcri pLoXkov /cat 
€TTLKeKapipL€vr]v €xov(jL TTJs dpLGTepds jLtaAAov. /cat 
35 Sta TO aveoTTaodai avojrepov rov 8ef tov v€(j)p6v ro 
•^TTap aTTTeraL rov Se^tou v€(f)pov iv Tracrtv eV rot? 

672 a Se^totS" yap to rjirap. 

"KxovGL 8' OL ve(j)pol jLtctAtCTra rcDv GnXdyxvcov 
TTipieXriv, i^ dvdyKrjg p^ev 8ta to SLrjdeiadai to 
TTepLTTOjpLa Sid Twv v€(f)pcov TO ydp AetTTOftCVOV 
at/xa KaOapov ov evTreiTTov cart, reAo? 8' evTreiplas 
6 aLpLartKrjg TnpeXr) /cat oTeap eoriv. [ajuirep yap ev 
Tols 7T€TrvpcopievoLs ^ripols, olov Tjj Te(f)pa, eyKara- 
AetVerat tl Trvp, ovtoj /cat iv tols TrevepLpLevois 
vypoZs' ey/caraAetVerat ydp tl ttjs elpyaopLevqs 

OeppLOTTlTOg pLOptOV. hlOTTCp TO XlTTapOV KOV(j>6v CGTi 

/cat €7Ti7ToXdt,€L iv TOt? vypols) €v avTolg pcev ovv 
10 ov ytVerat rot? ve<f)pOL? 8ta to ttvkvov elvai to 
oirXdyxyov , e^oj 8e TrepttWarat TnpLeXrj pL€V iv rot? 
77tjLteAcL>8ecrt, crreap 8' ev rots' o-rearcoSeotv ly 8e 
SLa(f)opd TOVTOJV eip'qTai rrporepov iv eripoLS. 

'E^ dvdyKrjg pLev ovv TTt/ieAajSets" ytVovrat 8ta 
ravTTjv TTjv aiTiav iK tcov GvpL^aLvovrcDV e| dvdyKTjg 
15 rots' e^ovGi v€cf)povs, eVe/ca 8e GCOTrjpLas /cat rou 
Oepprjv elvac ttjv (f)VGLV TrjV tujv v€(j>p(x)V. eoxaroL 
re yd/3 oWes aAeas' heovTai TrXelovos' to pikv ydp 
vojTov GapKwhis ioTLV, OTTOJS fj TTpo^oXrj Tols TTept 

^ ravra Peck : Trdvra villfiT. 

« See Book II. ch. v. 


motion they are bound to make their way upwards 
before the ones on the left. Tlius people raise the 
right eyebrow more than the left, and it is more 
arched. A result of this drawing up of the right 
kidney is that in all animals the liver, which is on the 
right side of the body, is in contact with it. 

The kidneys contain more fat than any other of the Fat in 
viscera. This is partly a necessary consequence upon ^^'^'i^y^ 
the percolation of the residue throuirh the kidneys : 
in other words, the blood which gets left behind there 
is easy of concoction because it is pure, and when 
blood undergoes complete concoction the final pro- 
ducts are lard and suet. (A parallel is to be found in 
the case of solid substances which have undergone 
combustion : e.g. a certain amount of fire gets left 
behind in ash. So, in fluid substances which have 
undergone concoction : some portion of the heat 
which has been generated remains behind. That is 
why oily substances are light and come to the top of 
fluids.) This fat is not formed actually in the kidneys 
themselves, because they are so dense : it collects 
outside them. In some it has the form of lard, in 
others the form of suet, according to the character of 
the animal. (The difference between the tw^o has 
been explained already in another connexion.) " 

This formation of lard, then, about the kidneys is 
the necessary consequence upon the conditions which 
necessarily obtain in animals that possess kidneys. 
But there is another reason for its formation, and that 
is, on purpose to safeguard the kidneys themselves 
and to preserve their natural heat. The kidneys are 
the outermost of all the \'iscera, and therefore they 
need more warmth. WTiereas the back is liberally 
supplied with flesh, which enables it to act as a 



672 a 

rrjv Kaphlav OTrXdyxi'OLg , rj 8' 6o(j)vs aaapKos 

[auapKoi yap at KapLTral ttolvtcov) • olvtI crap/cos" ovv 

20 Tj TTLfieXr] TTpo^Xrjjjia y iver ai roZs V€(f>poL?. en he 

hiaKpivovGi Koi TrirrovGi ttjv vyporrjra fiaXXov 

TTLOves ovres' to yap Xiirapov Oepfiov, Trerrei S* r] 


Ata ravras fxev ovv ras alrias ol vecfypol TTifxeXco- 

Seis eloiv, ev ndcn Se tols ^(x)ols 6 Sextos" dnLfjieXa)- 

repos eoTLV. atriov he ro rrjv (J)Vglv ^r^pdv etvai 

25 rrjv rcjv Se^LCJV Kal KivqrLKCjrepav' rj he Kivrjcn^ 

ivavria- nqKei yap to rrlov fiaXXov. 

Tols p^ev ovv dXXois Repots ovp(j)epei re rovs 

ve^povs ^X^''^ TTLOvaSy /cat TroAAa/cts" e-)(ovoiv oXovs 

TTepLTrXeoJS- to he TTpo^aTov orav tovto TrdOrj 

aTTodvrjGKeL. dXX dv Kal Trdvv TTioves wglv, dpLots 

so eAAetVet rt, dv prj /car' dp(f)OT€povs, dXXd /cara tov 

he^Lov} a'iTLOv he tov pLovov tj pidXiGTa tovto 

Gvp^alveiv eirl tcov TTpo^dTOJV, otl rot? piev mpe- 

XcoheGLV vypdv to ttIov, cocrr' ovx dpioiws cy/cara- 

KXeiopeva to, rrvevpaTa TToieZ tov ttovov. tov he 

G(f)aK6XLGpiov tout' a'iTcov eGTLv hid Kal TCOV dv- 


veodaL GvpL<f)epovTog , dpojs dv Xiav ylvcovTai tt loves, 
ohvvai davaT7](f)6poi Gvp^aivovGiv. tcx)v S* d'AAcov 
672 b Tol? GTeaTwheoLV tjttov ttvkvov to GTeap rj tols 
npo^dTOLS. Kal tw TrXrjOeL ttoXv Ta Trpo^aTa vrrep- 
^ctAAef yiveTai yap 7TepLve(f)pa Td^LGTa tcqv ^ojcov 
Ta Trpo^aTa TrdvTOJV. iyKaTaKXeLopevrjs ovv ttjs 
vypoTTjTOS Kal Tojv TTvevpdTOJV 8ta tov G(j)aKeXLGpidv 

^ oAA* av , , , he^iov post elaiv 1. 23 transponit Thurot. 


protection for the viscera about the heart, the loin, 
in common with all parts that bend, is not so supplied ; 
and this fat we have been speaking of serves as a 
safeguard to the kidneys in place of flesh. Further, 
the kidneys are better able to secrete and to concoct 
the fluid if they are fat, because fat is hot and heat 
causes concoction. 

These are the reasons why the kidneys are fat. In 
all animals, however, the right kidney has less fat 
than the left. This is because the right-hand side 
is dry and solid and more adapted for motion than 
the left ; and motion is an enemy to fat, because it 
tends to melt it. 

Now it is an advantage to all animals to have fat 
kidneys, and often they are completely filled with fat. 
The sheep is an exception : if this happens to a sheep 
it dies. But even if the kidneys are as fat as can be, 
there is always some portion which is clear of fat, if 
not in both kidneys, at any rate in the right one. The 
reason why this happens solely (or more especially) 
to sheep is as follows. Some animals have their fat 
in the form of lard, which is fluid, and thus the wind 
cannot so easily get shut up within and cause trouble. 
When this happens, however, it causes rot. Thus, too, 
in the case of human beings who suffer from their 
kidneys, although it is an advantage for them to be 
fat, yet if they become unduly fat, pains result which 
prove fatal. As for the animals whose fat is in the 
form of suet, none has such dense suet as the sheep 
has ; and moreover, in the sheep the amount of it is 
much greater ; the fact that they get fat about the 
kidneys much more quickly than any other animal 
shows this. So when the moisture and the wind get 
shut up within, rot is produced, which rapidly kills 



672 b ^ 

5 dvatpovvTaL raxecos' Sta yap rrjg aoprrjs /cat rrj^ 

(jyXe^os €vdv9 OLTTavra ro ttolOos irpos ttjv Kaphiav 
ol he TTopoi avvex^ls oltto tovtcov tcov cjiXe^cav etcrt 


He pi fJL€v ovv rrj? /capSta? Kal TrXevfiovos etprjrai, 
/cat TTCpl rJTTaros Kal OTrXrjvos Kal v€(f)pa)v. X. rvy- 

10 ^dveL 8e ravra K€)(CjpiGiJLeva dXXrjXijjv rep Sta^co- 
/Ltart. TOVTO Se to Sta^co/xa KaXovai rives (jipevas* 
o Stopi^et rov re TrXevfiova Kal rrjv Kaphiav. KaXelrai 
Se rovro ro 8td?co/xa iv rols eVat/xot?, ujairep /cat 
etpr^raL, (j^peves. e;^ft he iravra rd evaijjLa auro, 
Kaddirep Kaphiav Kal rjirap. rovrov 8' atrtov ort 

15 rov hiopLGpLOV X^P^^ ^^'^^ '^°^ '^^ TTepl rrjv KoiXlav 
roTTov Kal rod Trepl rrjv Kaphiav, ottojs t) rrjs 
aLuOrjriKTJs 4'^XV^ ^PXV diraOris fj Kal jjlt] raxv 
KaraXapL^dvYjrai hid rrjv diro rrjs rpo(f>7Js yLvofxevrjv 
dvaOvpiiaoiv Kal ro ttXtjOos rrjs eireicdKrov 6ep- 
{JLorrjros. errl yap rovro hieXaj^ev rj ^vois, olov 

20 TTapoLKohojjirjjjia TTOLVjoaGa Kal (f)payp.6v rag <j>pevas, 
Kal 8tetAe ro re rn-UcLrepov Kal ro drifiorepov iv 
OGOLS evhex^Tai hieXelv ro dvoj Kal Kdrco' rd fiev 
ydp dvco iarlv ov eveKev Kal ^eXriov, rd he Karco 
rd rovrov eveKev Kal dvayKaTov, rd ri]s rpo(f)rjs 
"Eart he rd Sta^cojLta Trpos fiev rds TrXevpdg 

25 uapKCoheGrepov Kal iGxvpdrepov, /caret p.€Gov 8' 
vpuevcoheGrepov ovrco ydp Trpds rrjv lgxvv Kal rrjV 
raGLV ;)^p')7crt/LtajTe/30V. Stort he irpos rrjv 6epp.drr]ra 
TTjv Karojdev olov jrapaejivdhes eiGi, GrjjjLelov €k rajv 


the sheep off. The disease makes its way directly to 
the heart through the Aorta and the Great Blood- 
vessel, since there are continuous passages leading 
from these to the kidneys. 

We have now spoken of the heart and the lung ; 
and also of the liver, the spleen and the kidneys. 
X. These two sets of viscera are separated from Diaphragm. 
each other by the diazoma, which some call the 
phrenes (diaphragm). This divides off the heart and 
the lung. In blooded animals it is called j)hrenes, as 
I have said. All blooded creatures have one, just as 
they all have heart and liver. The reason for this 
is that the diaphragm serves to divide the part 
round the stomach from the part round the heart, 
to ensure that the source of the sensory Soul may be 
unaffected, and not be quickly overwhelmed by the 
exhalation that comes up from the food when it is 
eaten and by the amount of heat introduced into the 
system. For this purpose, then. Nature made the 
division, and constructed the phrenes to be, as it were, 
a partition-wall and a fence ; and thus, in those 
creatures where it is possible to divide the upper 
from the lower, she divided off the nobler parts 
from the less noble ones ; for it is the upper which 
is " better," that ybr the sake of which the lower ex-' 
ists, while the lower is " necessary," existing ybr the 
sake of the upper, by acting as a receptacle for the 

Towards the ribs the diaphragm is fleshier and 
stronger, while in the middle it is more like a mem- 
brane : this makes it more serviceable as regards 
strength and extensibility. An indication to show 
why there are, as it were, " suckers," to keep off the 
heat which comes up from below, is provided by 



672 b 

GVfxpaivovrojv orav yap Sua rrjp yeirviacnv cXkv- 

GCOGLV vypoTiqra depfjirjv Kal TTepLrTCxjfiariKTjv^ cvdvg 
80 €7nS-qXoJs rapdrrei t7]v hidvoiav Kal ttjv alodiqGiv, 
hio Kal KaXovvrai (jypeves ojs {JLerexovaai rt tov 
(l)pov€lv. at Se iderexovGL /xev ouSeV, iyyvs 8* 
ovaaL rcov fierexovrajv eTTihriXov ttolovgl ttjv [lera- 
^oXrjV TTJ? SiavoLag. Sto /cat Aevrrat /caret fxeuov 
elcrlv, ov fiovov ef dvdyKrjs, on oapKcoSas ovaag ra 
85 TTpos ras" nXevpas dvayKalov etvau oapKco'^^Grepas , 
aAA* tv* on oXiyioTTjs iierexfJ^oiv LKpidhos' oapKco- 

673 a Sets' ydp dv ovGai Kal elxov Kal elXKOv fidXXov 

tVjLtaSa TToXX-qv. on he OepfiaLvofxevaL Ta^io^S 
iTTiSrjXov TToiovGi Tr)v aiadrioiv, uiqixaiveL Kal to 
Trept Tovs yeAcora? avfi^alvov yapyaXt^oficvoL t€ 
ydp raxv yeAcocrt, Sta to tt^v Kivquiv dcfiiKveladai 
6 Ta^^U TTpOS TOV rOTTOV TOVTOV, OepfJLaivofJLevov^ 8' 
rjpejjia 7Tol€lv ojJLCog eTTLSrjXov Kal KiveZv ttjv 8ta- 
votav TTapd ttjv TTpoaipeGiv. tov 8e yapyaXit,€Gdai 
yiovov dvdpojTTOv atVtov 17 re XcTTTOT'qs tov SepjJiaTO^ 
Kal TO {jLovov yeXdv tcov t,(jp(jjv dvOpcoTrov. 6 8e 
yapyaXiGpids yeXios €GtI Sta KivqGeojs:^ TOLavTT]? 
10 TOV [xopLOV TOV 7T€pl Tr)v {xaGxdXrjv. 

TiVfjL^alveLV 8e ^aat /cat irepl Tct? eV Tots' TToXefxois 
TrXrjyds et? tov tottov tov 7T€pl Ta? (f)p€vag yeXcjjTa 
Sid TTJV €K TTJs TrXrjyrj? yLVOjJbevrjv deppiOTriTa, tovto 

^ depiiaivoixevov Peck : depfiaivovat. vulg. : -ovaa SZ : -ovaav 
PUY. ^ KVTjaecjs Langkavel. 

° The Risus Sardonicus : see Allbutt and Rolleston, A 
System of Medicine^ (1910), viii. 642. 


what actually happens : whenever, owing to their 
proximity, they draw up the hot residual fluid, this 
at once causes a recognizable disturbance of the 
intelligence and of sensation. And that is why they 
are called phrenes : as if they took a part in the act 
of thinking (phronein). This of course they do not 
do ; but their proximity to those organs w^hich do 
so take part makes the change of condition in the 
intelligence recognizable. That, too, is why the 
phrenes are thin in the middle ; this is not due 
entirely to necessity (though as they are fleshy to 
begin with, the parts of them nearest the ribs must 
of necessity be more fleshy still) ; there is another 
reason, which is, to enable them to have as little 
moisture in them as possible, since if they had been 
wholly of flesh they would have tended to draw 
to themselves and to retain a large quantity of 
moisture. Another indication that it is when heated 
that they quickly make the sensation recognizable is 
afforded by what happens when we laugh. When 
people are tickled, they quickly burst into laughter, 
and this is because the motion quickly penetrates to 
this part, and even though it is only gently warmed, 
still it produces a movement (independently of the 
^\^ll) in the intelligence which is recognizable. The 
fact that human beings only are susceptible to 
tickling is due (1) to the fineness of their skin and 
(2) to their being the only creatures that laugh. Tick- 
ling means, simply, laughter produced in the way I 
have described by a movement applied to the part 
around the armpit. 

It is said that when in war men are struck in the 
part around the diaphragm, they laugh <* on ac- 
count of the heat which arises owing to the blow. 



673 a ^ , , , r , ^ , * 

yap iidXXov ianv ol^lottlgtcdv aKovaai Xeyovrcov tj 

TO TTepl rrfv K€(j)aXi]v, wg aTTOKOTTelaa (j)d€yy€rai 

15 T(x)v di'dpcoTTCOv. XlyovGi yap rives eirayopievoL Kal 
Tov "Oixrjpov, ojs Sta rovro TTOirjcravTOS 

(f)9eyyofxevr) S' dpa rod ye Kaprf kovltjglv 


d\X ov (j)6€yyofJLevov. rrepl Se ^ ApKahiav^ ovroj 

ro roLOvrov hieTTiGrevGav wore /cat Kpioiv eiroir]- 

uavro TTepl rivos rCov eyxcoplojv. rov yap lepews 

20 rod o7rAocr/xtou Ato? drroOavovros, v<f)* orov Se dSi^- 
Xov ovros,^ e(f>aodv rive? dKovoai ttJ? Ke(j)aXrjs 
d7TOKeKop,[xevr]g Xeyovorjg TToXXdKig 

€77* dvSpos dvhpa KepKTtSa? drreKreivev 
hio Kal l,r]r7]oavres S ovofia rjv ev rep roTTCp 
li^epKiSds, eKpivav. dhvvarov he (f)9eyyeodaL Kexoj- 
piopievris rrjg dprrjptag Kal dvev rrjs eK rov ttXcv- 

25 jLtovo? KLvrjoeaj£. rrapd re rots ^ap^dpotg. Trap* 
oh d-TTorepLvovoL ra^eios ras" Kecj)aXds, ovSev ttcj 
roLOvrov ovpL^e^rjKev. en 8* eirl rcov dXXcjv ^cocov 
Sid TtV alriav ov yiverai; \r6 fiev yap rov yeXco- 
ros TiXriyeiocJov rcov <f>pevcov eiKorcos, ovSev yap yeXa 
rwv dXXojv rrpoUvai Se ttol ro crcD/xa rrjs Ke(f)aXrjs 

80 d<j)7jpr]iJLevrjs ovSev dXoyov, iirel rd y* dvaifia Kal 

^ dpKaBiav Z, probat J. Schaefer de Jove apud Cares culto, 
pp. 370 sq. : Kapiav vulg^. : Kap . . av E : Kap P. 

^ Se dbrjXov ovtos Peek : Se St) dS^Acoj viilg. : codd. varia. 

<• Iliad, X. 457 and Od. xxii. 329. In both plaees the 
text of Homer has SOeyyoixevov (" As he spake . . ."). 

" The Berlin text here reads " Caria," but the Oxford ms. 
Z reads " Arcadia." A cult of Zeus hoplosmios is attested 
only for Methydrion, a town in Arcadia, and the name 
Kerkidas is found in Arcadia, not in Caria. (See A. B- 


This may be so ; and those who assert it are more 
credible than those who tell the tale of how a man's 
head speaks after it is cut off. Sometimes they cite 
Homer in support, who (so they say) was referring to 
this when he wrote 

As it spake, his head was mingled with the dust 

As he spake, his head was mingled with the dust.) ** 
In Arcadia ^ this kind of thing w^as at one time so 
firmly believed that one of the inhabitants was 
actually brought into court on the strength of it. 
The priest of Zeus hoplosmios had been killed, but 
no one knew who had done it. Certain persons, 
however, affirmed that they had heard the man's 
head, after it had been cut off, repeating the follow- 
ing line several times 

'Twas Kerkidas did slaughter man on man. 
So they set to work and found someone in the 
district who bore this name and brought him to trial. 
Of course, speech is impossible once the windpipe 
has been severed and no motion is forthcoming from 
the lung. And among the barbarians, where they 
cut heads off with expedition, nothing of this sort 
has taken place so far. Besides, why does it not 
occur with the other animals .'' [For {a) the story 
about the laughter when the diaphragm has been 
struck is plausible, for none of the others laughs ; 
and (6) that the body should go forward some distance 
after the head has been cut off, is not at all absurd, 
since bloodless animals at any rate actually go on 

Cook, ZeuSy ii. 290, who gives the evidence, and J. Schaefer, 
De Jove apud Cares culto^ 1912, pp. 370 f.) 

K 283 


673 a 

Cfj TToXvv xpovov SeSrjAojrat he Trepl rrjs alrias 

avTcov iv irepoLs.Y 

Tlvos fiev ovv €V6Kev ianv eKaorov tCjv oiiKay- 
yyo^v, etprjTaL- yeyove S' e^ dvdyKrjg inl rots evros 
TTepauL Twv (j)X€^a)v, i^idvai re yap tK/xaSa dvay- 
673 b Kalov, Kal ravrrjv alfiarLK-qv, i^ rjs ovvLurapiivris 
/cat TTTjyvvfievrjs yiveodai to crcojU-a tcx)V cjTrXdyxycov 
BcoTrep alfiaTLKa, Kal avrols p-ev 6p,oiav exovai ttjv 
rod oojpiaros <j)VULV, rots 8' aAAot? dvopioiav. 

XI. Yldvra 8e to, GirXdyxya iv vpiivi iariv 
6 TTpo^oXrjg re yap Set Trpos to dTraOrj etvai, Kal 

ravrr]? iXat^pds, 6 8' i>p,rjv tt^v (l)vcnv tolovtos' 
TTVKvos pi€V yap war dTroareyetv, daapKos 8e cocrrc 
pLTj e'A/cetv /XT^S' €)(€iv iKpidSa, Xenros 8' oircog kov- 
(j)os fj Kal fjLTjSev TTOLTJ ^dpos . jLteytCTTOt 8e Kal 
laxvporaroL rchv vp^evajv elalv ol re Trepl ttjv 
10 Kaphiav Kal Trepl rdv eyKe^aXov, euAdyco?* ravra 
yap helrai TrXeLGrr]? (f)vXaKrjs' rj p.ev yap </»uAa/<:ry 
TTepl rd Kvpia, ravra he Kvpia p,dXiara rrjs Jco^s". 

XII. "E^xovGi 8' evia fiev rcov l,a)cov Trdvra rdv 
dpiOp^dv avrojv, evia 8' ov Trdvra' TTola he ravra Kal 
hid riv* air Lav, etprjr at Trporepov. Kal rcov €)(6vrcjov 

15 he ravra hiacf^epovcnv' ov ydp opLoias ovre rds 

Kaphiag exovGL Trdvra rd e^ovra Kaphiav, ovre rcov 

aAAcuv tus" eLTTelv ovhev. ro re ydp rJTrap rot? p.ev 

rroXvaxihes eari roZs he p.ovo(f)ve(jrepov, Trpcbrov 

^ codd. edd. varia ; corrupta et inepta seclusi. 



living for a long time. The reason for these pheno- 
mena has been explained elsewhere.] 

We have now said what is the purpose for which 
each of the viscera is present ; but also they have 
been formed of necessity at the inner ends of the blood- 
vessels, because moisture, i.e. moisture of a blood- 
like nature, must of necessity make its way out there, 
and, as it sets and solidifies, form the substance of 
the viscera. That, too, is why they are blood-like in 
character, and why the substance of all of them is 
similar, though different from that of the other 

XI. All the viscera are enclosed in membranes. Membranes. 
Some covering is needed to ensure their safety, and 

it must be a light one. These conditions are fulfilled 
by a membrane, which is close-textured, thus making 
a good protection ; does not consist of flesh, and 
therefore does not draw in moisture or retain it ; is 
thin, therefore light, and causes no burden. The 
biggest and strongest membranes are those round 
the heart and the brain, which is natural enough, as 
it is always the controlling power which has to be 
protected ; therefore the heart and the brain, which 
have the supreme controlling power over the life of 
the body, need the most protection. 

XII. Some animals possess a full complement of Variationa 
viscera, some do not. We have already stated what '^"^^5^^. 
animals have less than the full number, and the 
reason. But also, the same viscera are different in 

the various animals that have them. For instance, 
the heart is not identical in all the animals which have 
a heart ; nor is any other of the viscera. The liver 
illustrates this : in some it is split into several parts, 
in some almost undivided. This variation of form is 



avrojv Tcov evat/xcov Kau Lwotokojv en oe fiaAAov 
/cat TTpo? ravra /cat Trpo? aAAr^Aa hia<^epei rd re rojv 

20 l-)(6vcov /cat (rajry rerpaTTohcov /cat (horoKcov. ro he 
TCOV opvldojv /xaAtCTxa TrpoaefK^epe? rep rcov ^coo- 
TOKCov €CTTtv T^VaTf Kadapov yap /cat kvaufjiov to 
XpcofJiOL avTOJV ean KaOdnep KaKeivcov. airiov he 
TO TO, acofjiara rovrcov evTTvovorara elvai /cat jLt-j) 
TToAA-j^y e;(etv (j)av\r]v Trepirrojaiv. hiorrep evia /cat 

25 oi)/c e;(et ;^oA')7y rtDv ^cooro/cwv to yap T^Trap ovpi- 
jSctAAeTat TToAi) fiepos Trpos evKpaoiav rod GaypLaros 
/cat vyieiav ev puev yap rep at/Ltart pLaXiora ro 
^ttxiJa toutcov TeAos", ro 8' rirrap alpariKcorarov pierd rrjv 
Kaphiav rujv GTrXdyx^'OJV . rd he rcov rerpanohcov /cat 
choroKOJV /cat rcov l)(9vcov ev(x>xp<^ twv TrXelorcov, 

30 ivLWV he /cat cfyavXa rravreXcog , coa-nep /cat to, goj- 
piara ^avXr^s rervx^f<e Kpduecos, olov ^pvvqs /cat 
■X^eXojvrjs /cat rcjv dXXojv ra)v roiovrojv. 

UTrXrjva 8' e;\;et to, jLtev Keparocjiopa /cat St;)^aAa 
OTTpoyyL'Aov, Kaddrrep at^ /cat rrpo^arov /cat tojv 
aAAa>y eKaarov, el /xt} Tt 8ta p^eyeOos evav^eGrepov 
674 a €;(et /caTo, pirJKo^, olov 6 rod ^o6? rrerTovdev' rd he 
TToXvGX^'h'rj irdvra pLaKpov, olov us" Kal dvdpojTro^ /cat 
Kvojv, rd he pcLvvxa pLera^v rovrcov /cat puKrov rfj 
jLtey ydp rrXarvv e;^€t tt^ he Grevov, olov Irmos /cat 
opevs /cat oVos'. 
6 XIII. Ov pLovov he 8ia^epet to, GTrXdy^va rrjs 
GapKos ro) oyKcp rod Gcoparos, dXXd /cat rco rrjv^ 
puev e^cxj rd 8' eGO) rrjv OeGiv e;)(etv. atTtov 8' oVt 

^ <TJii'> Peck. 2 TT^v KwSUYZ: Ttt vulg. 

« See above, on 650 b 24. C/. 677 a 19 ff. 

PARTS OF ANIMALS, III. xii.-xiii. 

found first of all even among the viviparous blooded 
animals ; but it is more noticeable among the fishes 
and oviparous quadrupeds, whose livers differ not 
only from those of the Vivipara, but also from each 
other's. In birds, the liver very closely resembles 
that of the Vivipara : in both, its colour is pure and 
blood-like. The reason for which is, that their bodies 
give a very free passage to the breath, which means 
that they retain very little foul residue; hence, indeed, 
some of the Vivipara have no gall-bladder, and this is 
largely due to the very considerable assistance given 
by the liver in maintaining a good blend" and healthi- 
ness in the body. This is because the purpose which 
these viscera serve lies chiefly in the blood, and after 
the heart the liver contains more blood than any 
other of the viscera. In most of the oviparous 
quadrupeds and the fishes the liver is yellowish, and 
in some of them it is altogether bad-looking, on a 
par Avith the bad blend of the rest of their bodies. 
This happens in the toad, the tortoise, and the like. 

As for the spleen : In horned animals that have 
cloven hoofs it is rounded : e.g. in the goat, the sheep, 
and similar animals ; unless greatness of size has 
made it grow out at some point lengthways, as in the 
case of the ox. In all the polydactylous animab the 
spleen is long, as in the pig, in man, and in the dog. 
In animals with solid hoofs the spleen is intermediate 
between the two and has the characteristics of both : 
in one place it is broad, in another narrow, as exempli- 
fied in the horse, the mule, and the ass. 

XIII. Now the viscera differ from the flesh not only 
in the bulkiness of their mass, but also in their 
situation, for the flesh is on the outside of the body, 
while they are inside. The reason for this is that 



TTjv (pvuLV €)(€L KOLvojvovaav Tttt? (pAeipL, /cat ra /X6V 

Toiv (fyXej^ajv ;^apiv, to, 8' oi5/<: dv€v (jyXe^cov ioriv. 

XIV. 'Ttto he TO u77o^6DjLia Kelrai r) KoiXia roXg 

10 t,a)Ois, Tols l^€v exovGLv OLOO(j>dyov fj reXevra rovro 

TO flOpLOV, TOt? 8e /XI7 eXOVGLV €v6v£ TTpOS Tip 

OTOfjiaTL' rrjs 8e KoiXias ixop^vov to KaXovjievov 

At' -^y 8' alriav ex^i ravra to. piopia rcov t^cvcov 
€Kaorov, (f)av€p6v Trdaiv. koI yap he^aoOai ttjv 
elaeXdovGav Tpo(f)rjv Kal ttjv e^iKfiaGfiev-qv dvay- 

15 Kolov iK7T6p.ipaL, Kal fjirj TOP avTou TOTTOV etvat rrjs 
t' OLTTeTTrov Kal rod TTepirraypLaros y elvai re riva 
8et T077oy ev w fxer a^aXXet. ro fxev yap rrjv ela- 
eXdovoav e^et fxopLoVy ro Se ro Trepirrajpia ro dxPV~ 
arov cQGTTep 8e ;^pdvos" erepos eKaripov rovrcov, 
dvayKalov SL€LXrj(f)9aL Kal rols roTTOis. dXXd nepl 

20 /Ltev rovrcov iv roZs rrepl rrjv yeveoLV Kal rrjv rpo(f)rjv 
oiKeLorepog ianv 6 hLopLGpios' rrepl 8e rijs Sta^opa? 
ri]s KOiXias Kal rojv GVvreXayp fJLoplojv vvv em- 

Ovre yap rols pieyeOeGiv ovre rols eiheoLV opLoias 
exovGiv dAArjAots" rd t>cpa' dAA' ooa puev eoriv avrojv 
d[j,(f)a)hovra rcov evaipLOJV Kal ruJv l^ojoroKajv, piav 

25 e^et KoiXiav, olov dvOpojiros Kal kvcov Kal Xewv Kal 
rdXXa oaa TToXvhaKrvXa, Kal 60a pLOJvvxo-, olov 
LTTTTOS, opevg, ovos, Kal ooa hlxoiXa /xev dpLcjxjjhovra 
he, olov v£, nXr^v et^ n 8td p^eyedos rod awpLaros 

^ vottXt]^ rj el ESUY (^ om. E) : va-nXrj^ ■nX'qv €i P et COrr. 
U : voTrXrjy^ in ras. et supra Kal xotpoj Z^, turn irX-qp el T?- : vs, 
el fM-q Bekker : vs. ttAtjv el fxrj Buss. 

» See De gen. an. Bk. II. chh. 6 and 7. 


PARTS OF ANIMALS, III. xiii.-xiv. 

their nature shares that of the blood-vessels : some 
of them exist for the sake of the blood-vessels, 
others do not exist apart from the blood-vessels. 

XIV. Below the diaphragm is the Stomach, which stomach 
is placed where the oesophagus ends (if there is an intestines. 
oesophagus ; if not, immediately next to the mouth). 
Next after the stomach and continuous with it is what 
is called the Gut. 

It must be obvious to everyone why all animals 
have these parts. It is a necessity for them to have 
some receptacle for the food they take in, and to 
expel it again when its moisture has been extracted 
from it ; and there must be two different places for 
these two things — the unconcocted food and the 
residue ; there must also be another place in which 
the change from one to the other is effected. Two 
receptacles, then, one for the incoming food, one for 
the residue which is no more use — as there is a 
separate time for these so there must be a separate 
place. However, it will be more appropriate to go 
into these matters in our treatise on Geiieration and 
Nutrition.'^ At the present we must consider the 
variations that are to be found in the stomach and its 
subsidiary parts. 

The stomach differs both in size and appearance in 
different animals. Those of the blooded Vivipara 
which have front teeth in both jaws have one 
stomach ; e.g. man, the dog, the lion, and the other 
polydactyls ; so also those that have solid hoofs, 
e.g. the horse, the mule, the ass ; and those which 
although they are cloven-hoofed have front teeth 
in both jaws, e.g. the pig. These rules apply unless 
the size of the frame and the character of the food 



Kat TTjV rrjg rpocprjg ovvaynv, ovaav ovk cvTrenrov 

30 ciAA' OLKavOaySr) Kal ^vXlk^v, e;^et TrXetovg, otov 
KaynriXos, woirep Kal ra Keparocfiopa' ra yap 
K€paro(f)6pa ovk eariv dficf)a)SovTa. 8ta rovro 8e /cat 
ri KajJLTjXos 01) Tojv a[jL(f)a)S6vrajv iarlv, aKeparog 
ovaa, Stct TO avayKaiorepov elvai avrfj rrjv KoiXiav 
€X€tv roiavr7]v rj rovg rrpoadiovs dSdvra?. coctt' 
674 b eVet ravrrjv ofioiav e^^i rots /xt] djU-^toSouat, Kal ra 
Trepl Tovs dSdyra? ofiOLCxJS e;)(et avrfj, cos" ovSev ovras 
npoepyov. dfia 8e /cat eVet t] rpo(j)r] aKavdojhris, 
TTJV 8e yAcorray dvdyKT] oapKajhy] elvai, Trpo? 
aKXrjporrjra rod ovpavov KaraKexp'^^TaL ro) e/c rojv 

6 oSovTCOV yecoSct 77 </'^crtS'. /cat fxrjpvKdl^eL 8' tJ 
KdpLTjXos coanep ra K€paro(f)6pa, 8ta rd ra? /cotAta? 
opioias €;^etv rot? K€paro(f)6poi£. rovrojv 8* eKaarov 
ttXelovs €X€l KoiXtag, olov TTpo^arov, /Sou?, atf, 
eXacfyos, Kal rdAAa rd roiavra ra>v ^cpcxjv, ottco? 
iTreih-rj rijs epyaoias cAAetVet 7re/3t rr]v rpo(f)r]v rj 

10 Xeirovpyia rj rov oropiaros 8td ri^v €V8etav rcov 
dhovrwv, r) rcov kolXlcov irepa Trpos erepas SexV^(^^^ 
rrfv rpo(f)rjv, rj piev dKarepyaorov , rj Se Kareipya- 
opiivrjv pidXXov, rj 8e TrdpLTrav, rj 8e Aetav. 8td rd 
roiavra rcov t,cx)(jL>v rrXeiovs ^x^i ronov? Kat pLopia. 

15 KoXovvrai he ravra KoiXia Kal KeKpv(f>aXo^ Kal 
i)^vos /cat rjvvorpov. ov 8' ^x^^ rporrov ravra npos 

^ bdxrjrai Peck : BexofJ-cvT] vulg. 


modify them : for instance, if the food is thorny and 
woody and therefore not easy to concoct, in which 
case the animal has several stomachs, e.g. the camel ; 
so also have the horned animals, as they have not front 
teeth in both jaws. Thus also the camel has not the 
two rows of front teeth either, although it has no 
horns ; this is because it is more necessary for the 
camel to have several stomachs than to have all these 
front teeth. So, as it resembles the animals which 
lack the upper front teeth in that it has several 
stomachs, therefore the arrangement of its teeth 
is that which normally accompanies the multiple 
stomachs : in other words, it lacks these front teeth, 
as they would be no use to it. And also, as its food 
is thorny, and as the tongue has of necessity to be 
of a fleshy character, Nature has made use of the 
earthy matter saved from the missing teeth to make 
the roof of the mouth hard. Again, the camel 
ruminates as the horned animals do, because it has 
stomachs that resemble theirs. Every one of the 
horned animals (such as the sheep, the ox, the goat, 
the deer, and the like) has several stomachs ; and the 
purpose of them is this : Since the mouth is deficient 
in teeth, the service which it performs upon the food 
is deficient ; and so one stomach after another 
receives the food, which is quite untreated when it 
enters the first stomach, more treated in the next, 
completely treated in the next, and a smooth pulp 
in the next. And that is why these animals have 
several such places or parts, the names of which are 
(1) the paunch (rumen), (2) the net or honeycomb-bag 
{reticulum), (3) the manyplies (omasum), (4) the reed" 
(ahomasum). For the relation of these to each other 

° Or, true stomach. 

k2 291 


674 b 

aXXr^Xa rfj deaei kol rot? elheaiv, eV re rrjs loropCas 
rrjs rrepl rd ^a)a Set decxipeiv /cat e'/c roiv avarofxajv. 
Aid T17V avTTjv 8' alriav /cat rd rtov opvldcjov 
yivos ex^t' hia(j)opav rrept to tt^? rpocf)7J? SeKnKov 
20 jjiopLOV. CTTel yap ovSe ravra oXoJS rr]v rod uro- 
/xaros" aTToStScocrt Xeirovpyiav [avohovra yap) Kal 
ovB^ (L 8tat/DT]cr€t ovd^ a> Aeavet Trjv Tpo(f)rjv exovai, 
8td TOVTO ra fxev 7Tp6 rrjg KoiXlag exovoi rov 
KaXovfievov irpoXo^ov olvtI rrjg rod oropiaros ipya- 
oias, ol 8e rov oloo(f)dyov TrXarvv, r) irpo rijs /voiAta? 
25 avrov jLtepo? n oyKcoSes eV co TTpodrjaavpL^ovoL rrjv 
OLKarepyaorov rpo(f>-qv, 7) ttJ? KotXlag avrrjs ri 
iiraveorriKos , ol 8' avrrjv rrjv KoiXiav Icrxvpav /cat 
GapKwBrj TTpos ro hvvaadai ttoXvv xpo^ov drjaavpi- 
^€tv /cat TTerrecv dXeLavrov ovcrav rrjv rpo(f)'ijv rfj 
8urd/xet yap /cat tt^ OeppLorr^ri rrjg /cotAta? ly (^vcng 
80 dvaXapL^dv€L rrjv rod uroparos eVSetav. ctcrt 8e 
Ttves" ot TOUTOJV oi}8ev e^'oucrtv, dAAd rov irpoXo^ov^ 
jiaKpov, oaa pLaKpoorKeXrj /cat e'Aeta, 8td ri^r rr^s" 
rpo(f>rjs vyporrjra. alriov 8' ort "j^ rpo^T] irdoi 
rovrois evXiavros , ware GvpL^aiveiv 8td ravra rwv 
TOLOvrojv rd^; /cotAtas" etvat vypds [8td tt^v dneiplav 
/cat TT^v rpo(f)'qv].^ 
675 a To 8e Ttijy Ixdvojv yivos e;)(et ^ev dSovras", rou- 
Tous" 8e Kapx^-pdhovr as ox^^ov ws elircZv Trdvres^' 
oXiyov ydp ri Ion yevos ro p.r) roiovrov, olov 6 
KaXovp,€vos GKdpos, OS Srj Kal 80/cet p^rjpvKd^eLV 

^ irpoXo^ov] cTOfxaxoi' Og-lc, collate Hist. An. 509 a 9. 

2 secludenda. 

' TTavres Ogle : ndvras vulg. 

" At 507 a 36 ff. ^ The gizzard. 

* Ogle reads " oesophagus." 



as regards position and appearance, the Researches 
upon Animals'^ and the treatises on Anatomy should be 

The same reason as has just been described accounts 
for the difference which presents itself in birds in the 
part which receives the food. Birds, like the other 
animals, do not get the full service from the mouth in 
dealing with the food — since they have no teeth at 
all, and they have nothing with which to bite up or 
grind down the food ; and so some of them have, 
before the stomach, what is called the crop, to per- 
form the work instead of the mouth. Others have 
a broad oesophagus ; or their oesophagus has a 
bulge in it, just before it reaches the stomach, in 
which they keep a preliminary store of untreated 
food ; or some part of the stomach itself sticks out. 
Others have a strong and fleshy stomach ^ which 
is thus able to store the food up for a long period 
and to concoct it although it has not been ground 
down ; thus Nature makes up for the deficiency of 
the mouth by means not only of the heat of the 
stomach but also by its special character. Other 
birds have none of these devices, but a long crop,^ 
because their food is moist : these are the long-legged 
marsh birds. The reason for this is that the food 
which all of these take is easily ground down, and 
the result is that the stomachs of birds of this sort 
are moist [o"\\ing to the unconcocted and moist state 
of the food]. 

The tribe of fishes have teeth : practically all have 
saw-teeth. There is one small group to which this 
does not apply, e.g. the Scarus,^ as it is called, and 
it seems reasonable to suppose that this is why 

^ The parrot-fish ; see above, 6Q2 a 7. 



675a ^ ^ 

5 evXoycos Sia ravra {xovos- Kal yap ra fxr] dju,(^co- 
Sovra K€paro(f)6pa 8e fxrjpvKd^ei. o^eXg 8e Travras^ 
€xovGiv, a)GT€ SteAety /xev SvvavraL, <f}avXojs Se 8t- 
eXeXv ivSLarpL^eiv yap ov^ olov re )(povil,ovTag' 8l6- 
7T€p ovSe TrAaTet? exovaiv oSovrag, ouS' eVSe;^€- 
rai Xeaiveiv juctrr^v av ovv elxov. ert Se arofiaxov 

10 ol fjL€v oXojs ovK exovGiV, ol he ^pa^vv. dAAa irpos 
rrjv ^oi^detav rrjs Trei/jeoj? ol fiev opviBajheis exovat 
ras KOiXias /cat uapKwSeis, olov Keorpevs, ol Se 
TToXXoL TTapa rrjV KOiXiav d7TO(f)vdhas nvKvas, tv* 
iv ravrais coavrep eV TTpoXaKKiois drjaavpti^ovre? 
ovacrrjTTCjDGL Kal TT-errcocrt ttjv rpocjyiqv. exovui 8' 

15 evavTLOJs oL lxOv€9 rots' opvioi ras d7Toj)vdhas' ol 
liev yap IxOv^S dvco rrpos rfj KOiXla, raJv 8' opvidcov 
OL exovres diro^vdhas Karoj npos rep reXeu rov 
ivrepov. exovGL 8* d7T0(f)vdSag eVta /cat Ta>v Jojo- 
tokcjov ivrepLKa? Kdroj 8td rrjv avrrjv alriav. 

To 8e rcov IxOvcxJV yevos aTrav, 8td to evhecGrepcos 

20 e;^etv ra rrepl ttjv rrjs Tpo(f)7]s epyaacav, dAA' 
aTreTTra hiaxojpeZv, XaipLapyov rrpos rrjv Tpo(f)T^v 
iaTL, Kal Tojv dXXojv 8e TrdvTOJv oua evdvevrepa' 
rax^tas yap yivop.eviqs rrjs Siaxcopijoecjos, Kal Sid 
ravra ^pax^lag ovoiqs rrjs dTToXavaeoj? , rax^Xav 
dvayKalov yiveod ai irdXiv /cat r-qv eVt^u/xtav. 

26 Td 8' dii<j)OL>hovra on fxkv fxiKpdv e;^et KoiXiav 
CLprjrai Trporepov els Scacfiopds 8e TTLTrrovoi hvo 
irdoai ax^Bov ra fxev yap rfj rrjs kvvos opLoiav 

^ TTavras S: TTavres vulg. 

" Probably some kind of mullet. 
* ** Caecal appendages " (Ogle), or " alimentary sacs." 
" The vermiform appendix. 


it alone ruminates, for horned animals which have no 
teeth in the upper jaw also ruminate. All teeth in fish 
are sharp ; this enables them to bite up their food, 
though somewhat unsatisfactorily ; this is because 
they cannot spend long over mastication ; hence 
they neither have flat teeth nor may they grind 
the food down ; therefore it would be idle to have 
the teeth. Furthermore, some fishes have no gullet 
at all, others have a short one ; but, in order to as- 
sist the process of concoction, some of them, hke the 
Kestreus,^ have fleshy stomachs, similar to those of 
birds ; the majority, however, have a large number 
of appendages ^ by the side of the stomach, in which 
to store up the food as it might be in additional cellars 
and there putrefy it up and concoct it. The ap- 
pendages of fishes are, however, quite different from 
those of birds. In fishes they are fairly high up 
beside the stomach, whereas when present in birds 
they are down below at the end of the gut. Some 
of the V ivipara also have appendages ^ of this latter 
kind, and their purpose is the same. 

The whole race of fishes is gluttonous for food, 
because their equipment for reducing it is defective, 
as a result of which most of it passes through un- 
concocted. Of all, those which have a straight intes- 
tine are especially gluttonous, since the food passes 
through quickly, which means that their enjoyment 
of it is brief, and therefore in its turn the desire for 
food must come on again very quickly. 

I have already said that in animals with front 
teeth in both jaws the stomach is small. These 
stomachs fall into two main classes. Some have a 
stomach resembUng that of the dog, some that of 

" 295 


676 a ^ 

exovGL KoiXiav, ra Se rfj rrjs vos- eari 8* t] [lev Trjg 

vos /xet^cov /cat rivas exovoa fierplas TrXaKag TTpos 
TO xpovLOJTepav yiveodai rrjv ireifjiv, r] 8e rrjs kvvos 
30 fiiKpa TO fieyedos Kal ov ttoXv tov ivTepov virep- 
pdXXovoa Kal Xeca to. ivTog. jLtero. yap ttjv KOiXiav 
7) TcDv ivTepcjov eyKeiTai (j)vois rrdai rot? l,ajois. exet 
he hia(j>opas iroXXas, Kaddirep rj KotAta, Kal tovto 
TO fjLopLOV. Tols fJLev ydp OLTrXovv ioTi Kal opLOiov 
avaXvopievov, tols S' dvofJiOLOv ivloLs puev ydp evpv- 

35 T€pOV TO TTpos TTJ KOlXLa, TO Se TTpOS Tip TcAct 

OTevoTepov^ (hioTrep at Kvves /xerd ttovov rrpotevTai 
675hrrjv TOLavTTjv TrepLTTWOLv), Tols 8e TrXeioaiv dvojOev 
GTevoTepov,^ Trpos tco re'Aet 8' evpvTepov. 

Met^O) 8e Kal dvaSLTrXcnoeLs exovTa TToAAds' rd 
Tibv K€paTO(j)6pa)v ecrrt, /cat ol oyKOL ttjs /cotAtas" 
TovTOLs pLeit^ovs Kal rcDv ivTcpcxJV 8td to pteyedos' 
5 TTavra ydp cLs etTretv pieydXa rd K€paT0(f)6pa 8td 
TTjv KaTepyaaiav tt^v ttjs Tpo(f)rjs. Trdui 8e toZs /xt] 
evdvevTepoLs Trpo'Cdv^ evpvTepov ytverat to pLopuov 
TOVTO, Kal TO KaXovpLevov KoXov exovoL, Kal tov 
ivTepov TV(j)X6v Tt Kat oy/ccoSes', etT* e/c tovtov 
TTaXiv GTevoTepov^ /cat elXiypievov. to 8e /LteTa 
10 TOVTO evdif TTpos TTjv €^ohov 8taTetV€t TOt» TrepLT- 
TOjpLaTOs, Kat TOLS /xev tovto to pLopLOV, o /caAow- 
pL€vos dpxds, kvlocjoStjs ioTLy ToZs 8' aTTLpLeXos. 
TrdvTa 8e TavTa pi€pi7]xdv7}TaL Tjj cfyvaeL TTpos Tds 
dppLOTTOvoas ipyaalas rrepl ttjv Tpo(f)'rjv Kal tov 
yLvopL€VOv TTcpLTTcopiaTos. TTpo'CovTL ydp Kal KaTa- 
^aLVOVTL TO) TTepLTTcopLaTL €vpvxojpLa ytVcTat, Kol 
15 TTpos TO pLeTapdXXeLV loTapLevo) tols evx^XoTcpois 

* arevatTepov bis vulg. ^ irpo'Cov Peck : irpolovaw vulg. 

^ cmvoTipov SU : arevwrepov Vulg. 



the pig. The pig's stomach is larger than the dog*s, 
and it has some folds of medium size, so as to prolong 
the time of concoction. The dog's is small in size — 
not much bigger indeed than the gut, and its inner 
surface is smooth. The gut has its place next after 
the stomach in all animals. Like the stomach, this 
part too presents many various forms. In some 
animals it is simple and similar throughout its 
length, when uncoiled ; in others it is not similar 
throughout. Thus, in some it is wider near the 
stomach, and narrower towards the end (that is why 
dogs find difficulty in discharging their excrement) ; 
in the majority, however, it is narrower at the top, 
and wider at the end. 

In the horned animals, the intestines are longer and 
have many convolutions ; and their bulk (as well as 
the bulk of the stomach) is greater, owing to the size 
of the animal : horned animals being, on the whole, 
large in size because of the ample treatment which 
their food receives. Except in those animals where 
it is straight the intestine gets wider as it proceeds, 
and they have what is called the colon and the 
blind and swollen part of the gut ° ; and then after 
that point it gets narrower again and convoluted. 
After this, it goes on in a straight line to the place 
where the residue is discharged ; and in some this 
part (which is called the anus) is supplied with fat, in 
others it is devoid of fat. All these parts have been 
devised by Nature to suit their appropriate functions 
in treating: the food and in dealinfj with the residue 
produced. As the residue proceeds on its way and goes 
downwards, it finds a wider space where it remains 
in order to undergo transformation ; this is what 

" The caecal dilatation. 



675 b 

t(Jl)V t,ix)(x)v /cat TrAetovos- SeofievoLs rpo(f)rJ£, Slcl to 
IJL€yedo£ 7} T7]v depjionqra rcov tottcov. etr* iv- 
revdev ttolXlv, (Zanep oltto rrjs avco KoiXias Sep^erat 
GTevorepov^ evrepov, ovrcxjg eV rod kcoXov /cat rrjs 
€vpv)(^ujpias iv rfj koltco kolXlo. ttolXlv els orevo- 


20 Tepov epx^rai /cat ets" rrjv eAi/ca ro TTepLrrcxjfJLa 
e^LKfiaopievov TrdpLTrav, ottojs rajjuevrjraL rj (f>vai,s 
Kal fiT] ad poos fj r) efoSo? rod TTepLrrwfJLaros. 

"Ocra fjiev ovv efvat Set tojv I^cocjv ooxjypoviorepa 
TTpos TTjv rrjs Tpo(f)rjs ttoltjglv evpvx(^pio.s p-^.v ovk 
ex^L fieydXas Kara ttjv Kara) KoiXiav, e'At/ca? 8* 

25 €;\;et TrXeiovs /cat ovk evdvivrepd icmv. rj pLev yap 
€vpv)((ji)pia TTOiei ttXtjOovs €7n6vp,Lav, r) 8* evdvrrjg 
raxvTrjra iTTiOvpiias' SioTrep 60a tojv l^cpojv -^ aTrAas" 
ex€i ^ €vpvx(J^povs rds VTTohoxd?, rd pL€v ets" vXrjdos 
yaarpLpLapya rd 8* els rdxos iaruv. 

'E7r£t 8* iv rfj dvoj /xev kolXlo. Kard rrjv 7rpa)rr)v 

80 €tcro8ov rrjs rpo(f)rjs veapdv dvay/catov efvat rrjv 
Tpo(j)'qv, Kdro) he TTpo'Covoav KOTrpcohr] Kal e^- 
iKpiaapievqv, dvay/catov etvat n Kal ro piera^v, 
iv a) pLera^dXXet Kal ovr* en Trp6o(j)aros ovr rjht] 
KOTTpos. 8td rovro Trdvra rd roiavra ^coa rr)v 
KaXovpievr]v ex^L vrjomv Kal iv rep pLerd rrjv KoiXiav 

85 ivrepcp ro) Xenrcp' rovro yap piera^v rrjs r* dvoj, iv 
fj rd drreTTrov, Kal rrjs Kara), iv fj ro dxp^^CFTOv rjSr] 
rrepirrwpia. yiverai 8' iv ttclgl pLev, S-qXrj 8* iv roXs 

^ oT€vwT€poi' bis Langkavel. 

" i.e. the " stomach." 
^ i.e. the " large intestine." 


happens in the animals which need and take more 
food owing either to their size or to the heat of these 
parts of the body. After this, just as it goes into a 
narrower part of the intestine after it leaves the upper 
gut," so also it goes into a narrower channel after 
the colon or wide part of the lower gut,^ and into 
the spiral coil ; into these the residue passes when 
its juices have been completely exhausted. In this 
way Nature is enabled to keep the material in store, 
and the residue is prevented from passing out all at 
the same moment. 

In those animals, however, which have to be more 
controlled in their feeding, there are no great wide 
spaces in the lower gut, but their intestine is not 
straight, as it contains many convolutions. Spacious- 
ness in the gut causes a desire for bulk of food, and 
straightness in the intestine makes the desire come 
on again quickly. Hence, animals of this sort are 
gluttonous : those with simple receptacles eat at very 
short intervals of time, those with spacious ones eat 
very large quantities. 

Since the food in the upper gut, when it has just Jejunum, 
entered, must of necessity be fresh, and M'hen it 
has proceeded further downwards must have lost its 
juices and be practically dung, the organ which lies ' 
between the two must of necessity be something 
definite, in which the change is effected, where food 
is no longer fresh and not yet dung. Therefore all 
animals of this sort have what is called the jejunum, 
which forms part of the small intestine, which is next 
to the stomach. That is to say, it has its place 
between the upper gut, where the unconcocted 
food is, and the lower gut, where the now useless 
residue is. All these animals have the. jejunum, but 

' 299 


676 a jLtet^ocrt Kal vrjarevaauLV dAA' ovk iSrjSoKOcnv' t6t€ 
yap Srj^ olov^ fieTalxf-itov yiverai rcov tottcuv diJi(f)0- 
repcxjv, ihrjhoKOTCov he fXLKpo? 6 Katpo? rrjs /lera- 
^oXrjs. rots [jL€V ovv drjXeoL^ yiverai ottov av rvxij 
5 Tov dvo) Ivripov rj vtjotls' ol 8* dppeves* exovGL irpo 
rov rv(f)Xov Kal rrj<^ Karoj KotAta?. 

XV. "Kxovai Se TTjv Ka\ovp.ev7]v TTveriav rd jj-ev 
TToXuKolXia Trdvra, rcov Se pLOvoKoiXicxJV haGVirovs. 
ex^i Se rd exovra tojv ttoXvkolXlojv ttjv TTveriav ovr 
iv rfj fjLeydXrj KoiXia ovr iv ro) K€Kpv(f)dXcp ovr* iv 

10 to) reXevratci) ro) rjvvarpcp, aAA* iv rw jLtera^u rov 
reXevraiov Kal \hvof tcjv TTpcjrcov, iv rep /caAou- 
}ievcp ixivcp. e;^et Se ravra Trdvra TTveriav hid rrjv 
7TaxvrT]ra rod ydXaKros' rd 8e fiovoKoiXia ovk 
e^et, XeTTrov ydp rd ydXa ra)v {jlovokolXlojv. Slo 
rcov {lev Keparocf)6pcov Tnjyvurai, rojv 8' aKepdrcjv 

15 ov TT-qyvvrai ro ydXa. rep 8e 8acru7roSt yiverai 
TTveria 8td rd vepLeodai ottcoSt] iroav 6 ydp roiov- 
ros x^i^os" CTvvLorrjcnv iv rfj KoiXia rd ydXa roZs 
ipL^pvoLS. SiorL 8e rcov ttoXvkolXlojv iv rep ix^^^ 
yiveraL rj TTveria, e'lprjraL iv rols TTpo^X-qpLaaLV. 

^ 817 Z : 17877 vulg-. 

2 olov PZ, om. vulg. 

' ^T^Aeai] TeAet'ots Z : TrXeloat. Piatt. 

* dppeves] Kvves Piatt. 

^ [8uo] secludendum. 

" This seems to mean that \vhen the animal is fastinp: the 
two receptacles do not bulge, and so the jejunum is visible ; 
and though alter the animal lias fed you might expect to see 
the jejunum^ because it should be full of food which is being 



it is apparent only in the larger ones, and in them 
only when they are fasting, not when they have 
recently been eating, for when they are fasting, there 
is an interspace between the two receptacles, whereas 
when they have been eating, the time taken by the 
change is short." In females the jejwiuju can have its 
place in any part of the upper intestine ; in males 
it is placed immediately before the caecum and the 
lower gut. 

XV. Wliat goes by the name of Rennet is present Rennet. 
in all animals which have a multiple stomach ; the 
hare is the only animal with a single stomach which 
has it. In the former class the rennet is not in the 
paunch^ nor in the reticulum, nor in the ahomasum (the 
last of the stomachs) ; but in the stomach between 
the last one and the first ones, i.e. the so-called 
omasum (manyplies).'' All these animals have rennet 
because their milk is so thick ; similarly, the single- 
bellied animals have no rennet, because their milk 
is thin. This also explains why the milk of horned 
animals coagulates, while that of the hornless does 
not. As for the hare, it has rennet because it feeds 
on herbs with fig-like juice ; and this juice can 
coagulate the milk in the stomach of sucklings. I 
have stated in the Problems'^ why, in the animals 
that have many stomachs, the rennet is formed in 
the manyplies. 

transmuted inside it (see above, 675 b 32), it is not visible, 
because the change is effected so rapidly. 

* Lit. " the great stomach." 

' See above, 674 b 14 if. 

^ No such reference can be found. 



676 a 

Tov avTov 8e rponov ex^i ra nepl ra OTrXdyxva 
Kal TTjv KoiXiav kol rcav elprjiiivojv [lopLCov eKaarov 
TOLS reTpanoai fxev cootokols 8e ra>v ^cvojv Kal rols 

25 aTToaiv, olov rols 6<J)€glv. Kal yap rj rcov 6(f>€OJV 
(f)VOL? iarl uvyyevr]s tovtol?' ofiOLa yap eon cravpcp 
fjLaKpo)^ Kal (XTToSi. TOvroLS Se Kal rots' Ix^vcri, 
TTOLvra TTapaTrXrjGia, ttXtjv ra fiev e;\;6t TrXevyiova 8td 
TO 7T€^ev€LV, ol S' ovK e;^ouo'tv, dAAa ^pdyxi^ci dvrl 
TOV TrXevjjLOVOs. Kvanv S* ovd^ ol IxOves exovaiv 

80 ovre rovrcov ovSev ttXtjv x^^^^V^' TpeneraL yap €ls 
rds (fioXiSas ro vypov 6Xiyo7T6ra)v ovrojv Std rr]V 
dvaLfjLorrjra rod TrXevjiovos, Kaddrrep rols opvioiv 
els ra Trrepd. kol eViAef/catVet he ro nepLrrcxifia 
TTaoL Kal rovrois, ayoirep Kal rols opviaiVy hiort^ iv 
rols exovGL Kvoriv e^eXdovros tov TrepLrrcojJLaros 

85 v(j)[araraL dXfJLvpls yeojhiqs iv rols dyyeiois' ro yap 
yXvKv Kal TTorLfiov dvaXioKerai hid Kov<f)6rr]ra ets" 
rds odpKas. 
676 b Tcxjv S' 6(j>e(x)v ol ex^is npos rovs dXXovs exovoi 
TTjv avrrjv hLa(f)opdv rjv Kal iv rols lxOvctl to. 
aeXdx'T] TTpos rovs d'AAous" l,iporoKovoL yap e^o) Kal 
rd aeXdx'T] Kal ol ex^LS, iv avrols (poroK-qoavra 
TTpcbrov. pLovoKoiXia he rrdvra rd roiavra eori,, 

^ (xaKpw Y : fxaKpcp ^ vulg. ^ Sio'ti Ogle : 8i,6iT€p vulg, 



What has been said already on the subject of the 
viscera, the stomach, and each of the other parts 
mentioned, appUes to the footless creatures (such as 
the Serpents) as well as to the oviparous quadrupeds. 
Indeed, the Serpents are akin to these : for a serpent 
is like a long and footless lizard. A third class in 
which all these parts are similar is the Fishes : the 
only difference is that the first two classes are land- 
creatures and therefore have a lung, whereas fishes 
have no lung but gills instead. Fishes have no 
bladder, nor has any of these creatures (except the 
tortoise) ; the reason is that they drink little (because 
their lung is bloodless), and the moisture in them 
is diverted to the horny scales, just as in birds it is 
diverted to the feathers. And in all these creatures, 
as in birds, the residue ^ is white on the surface, 
since in those animals that have a bladder, when the 
residue has been voided an earthy salt deposit 
settles in the vessels, the sweet and non-briny por- 
tion, o^^^ng to its lightness, being used up upon the 

The Vipers have the same peculiarity among the 
Serpents as the Selachia have among the Fishes. 
Both of them are externally viviparous, though 
they first produce their ova internally. All these 

" See Introduction, pp. 32 ff. 



676 b 

5 KaBairep raAAa ra d^^cuSovra* kol GTrXdyxva- Se 
TTaiJLTrav fxiKpa k^^i, ayairep rdAAa ra firj exovra 

KVOTTLV. ol 8' O^etS" Sid T7)v TOU CTCU/XaTO? lJLOp(f)rjV, 

ovoav fiaKpav /cat ctt^vt^v, /cat rd ax'r]yio,ra tcx)v 
OTrXdyxyojv cxovgl Std ravra jLta/cpd /cat rot? rdiv 
dAAojv t,cx)cov dvofioia, Std rd Kaddirep iv rvircp rd 

10 ax'TjlJ-CLT^ avTcov TTXaoOrjvai Std rdv tottov. 

ETTtVAoov Se /cat fxeaevrepiov /cat rd Trept T17V 
Toiv ivTcpajv (j)V(jiv, en Se rd Std^co/xa /cat ri^v 
KapStav TrdvT e;^et rd eVat/xa rcov ^wojv, nXevfiova 
Se /cat dprrjpLav irdvra ttXtjv tcov Ixdvcov. /cat tt]v 
decTLV Se T-^s" dprrjpias /cat rou olao^dyov ndvra 

15 ra e;^^^'''^^ ofiOLcos e;^et Std rds" elprjiievag atrta? 

II. 'Ex^*^ ^^ '^^^ ;Y^A'))v rd TroAAd rdiv ivalfxcov 
L,a)(jDv, rd fjLev eirl ro) rjiraTt, rd S' aTTrjprrjfxevr^v eirl 
Tois €VT€poLs, COS" oucrav ou;^ rjrrov e'/c rr^? /cdrca 
KoiXias TTjv (f)VGLv avTrjs . St^Aov Se jLtdAtcrr' eTTt rcDv 

20 Lxdvcov OVTOL yap exovcrl re Trdyres", /cat ot TroAAot 
77/90? Tot?^ ivrepoLs, €vioi Se Trap' oAov rd evrepov 
7Tapv(f)aaiJi€vr]v, otov rj dpua' /cat rcov 6(f)€a)v ol 
irXeloroi rdv avrdv rpoirov. hioTrep ol Xeyovres rrjv 
(fiVGLv rrjs x^^V^ alaOijoecos nvos etvat X^P'^ °^ 
KaXws XeyovGLV (f)a(jl ydp etvat Std rovro, dnajg 

M rijs ^^XV^ '^^ TTepl rd rjirap fxopiov haKVOVoa jikv 
GvvLGrfj, Xvopiivr] S' IXecov TTOifj' rd [xev ydp oXojs 

^ Toi? PYZ et corr. U : om. viilg. 

« See 665 a 10 ff. ^ See 650 a 14. 

" This seems to refer to the views expressed in Plato, 
Timaeus^ 71 d. 


creatures have one stomach only, as do the other 
animals that have front teeth in both jaws. And 
their viscera are quite small, as are those of the 
other creatures which have no bladder. However, 
on account of the shape of the serpents' bodies, 
which is long and narrow, the shape of their viscera 
too is consequently long, thus differing from those 
of other animals. This is because the shape of them 
is fashioned, as though in a mould, on account of the 
space available for them. 

All blooded animals have an omentum, a mesen- 
tery, and the whole intestinal equipment ; also a dia- 
phragm and a heart ; and all but the fishes have a 
lung and a windpipe too. The relative positions of 
the windpipe and the oesophagus are the same in all 
of them. The reasons for this have been given 
already. ** 

II. The majority of the blooded animals have a Gaii-biadder 
gall-bladder in addition. In some it is placed up ^^'^ ^^^®' 
against the liver ; in others it is separate from the 
liver and placed against the intestines, indicating 
that equally in these its derivation is from the lower 
gut.^ This is clearest in the fishes, all of which have 
one, and in most of them it is placed against the 
intestines, though in some it runs along the whole 
length of the intestine, like a woven border, as in 
the Amia ; a similar arrangement is found in most of 
the serpents. Hence, those who assert that the gall- 
bladder is present for the sake of some act of sensation 
are wrong. They say its purpose is as follows : — 
on the one hand (a) to irritate that part of the Soul 
which is around the liver, and so to congeal it '^ ; and 
on the other hand (6) by running free to make that 
part cheerful. This cannot be true ; because some 



676 b ^ ^^ 

ovK €X€L x^^W* ^'^^^' '^'^'^og Kal opevg /cat ovog /cat 
e'Aa^o? Kal irpo^' ovk e;^et 8' ovh* rj KOLjjLrjXos 
OLTTOKeKpiiJLevqv, dAAa ^Ae^Sta x'^XwSr] fxaXXov ovk 
€xei 8' ouS' Tj (f)coKrj ;^oA7]v, ouSe tcov BaXarriojv 
80 heX(j)i5. iv he rols ylveoi tols avroZs ra fikv c^civ 

cf)aLV€TaL TO, 8' OVK e)(€LV, OLOV cV TfS TCOV flVcbv 

TOVTCxJV 8' ecrrt /cat o avdpojTTOs, eviOL jiev yap 
ij)aivovTai e^ovres ^pXriv eirl rod T^Varos", eVtot 8' 
ou/c exovres' 8to /cat ytVerat dfX(f)LG^T^T'q(jLS irepl 
oXov rod yevovs' ol yap evrv^ovres oTTorepcjcrovv 
35 exovGL rrepl Trdvrwv VTToXapi^dvovGiv djs d-navrcxiv 
ixdvTa>v. crujLt^atVet 8e rotourov /cat Trepl rd Trpo- 
jSara /cat rag atyas" to, /xep' yap TrAetara rovrcuv 

677 a e;\;et x^^W> <^^' Iviaxov puev rooavrrjv wore 8o/cety 

repas elvai rrjv UTrepjSoArjv, otov eV Nafoj, iviaxov 
8' ou/c exovGLV, OLov iv XaA/ct8t ttj? EujSotas' /cara 
Ttva T0770V T'jjs' x^P^^" auTcov. €Tt 8e, cjorrep ^tprj- 
6 rat, T^ "T"^^ lxOva)v aTTiqpTiqr ai ttoXv rod rJTTarog. 
OVK 6p9(x)s 8' ioiKaaiv ol Trepl ^Ava^ayopav vtto- 
XajJL^dveiv ojg alriav ovaav rcov 6^ea>v voarnidroiv' 
VTTep^dXXovaav ydp dTToppaiveiv irpos re rov TrXev- 
fjLova Kal rd? (f)Xe^as Kal rd irXevpd. cr;(e8oy yap 
ols ravra ovjx^aivei rd irdO-q tCjv voacov, ovk 
10 exovGi xoX'qv, ev re rat? dvarOjLtat? dv eylvero rovro 
(f)avep6v' en 8e to ttXtjOos ro r iv rols dppcoorr]- 
fiaoLV vndpxov Kal ro aTToppaivoixevov davjji^XTjrov. 
dAA' eoLKev rj X^^V^ Kaddrrep Kal rj /card ro dXXo 

" This is true of quite a number of species, and as Aristotle 
says, the gall-bladder is specially variable in mice. In man, 
its absence is rare ; and Aristotle's statement may well be 
derived from his observation of aborted embryos, in which 
the gall-bladder develops somewhat late. 


animals have no gall-bladder at all, such as the horse, 
the mule, the ass, the deer, and the roe ; and the 
camel has no distinct gall-bladder, but what would 
better be described as consisting of small biliary- 
vessels. There is no gall-bladder in the seal, nor 
(among sea-animals) in the dolphin. Sometimes in 
the same group there are some animals which look as 
if they have one, and some as if they have none** : 
This is true of the Mice ; and also of the human 
species, as in some individuals the gall-bladder is 
placed against the liver and is obvious ; while in some 
it is missing. The result of this has been a dispute 
concerning the group as a whole. Whatever an 
observer has found to be the condition of the indi- 
viduals he happens to have seen, that he holds is true 
of every individual throughout the group. The same 
has occurred with regard to sheep and goats, most of 
which have a gall-bladder ; but, whereas in some 
individuals it is so large that its excessive size is 
portentous (e.g. in Naxos), in others it is entirely- 
absent {e.g. in a particular district of Chalcis, Euboea). 
A further point, already mentioned, is that in fishes 
the gall-bladder is separated from the liver by a good 
distance. Moreover, it is safe to say that Anaxa- 
goras's school is wrong in holding that the gall-bladder 
is the cause of acute diseases : they say that when it 
gets too full it spurts its liquid out into the lung and 
blood-vessels and sides. This must be ^\Tong, because 
nearly everyone who suffers from these affections 
actually has no gall-bladder, and this would be proved 
if they were dissected. Besides, there is no com- 
parison between the amount of bile which is present 
in these ailments and that which is emitted from the 
gall-bladder. No ; it seems probable that, j ust as the 

' 307 


aojfJLa ytvofjievr] TvepLTrajfia rt ecrriv i] avvTrj^tg, 
OVTOJ /cat rj errl ro) rjirari X^^V TreptrrcojLta etvat koI 

15 ovx €V€Kd Ttvos", a)G7Tep Kal rj ev rrj KOiXia Kai 
iv TOis ivripois vTroaraat?. Karaxp^jrai fJLev ovv 
ivLore rj (f)vaL? ets" to cu^eAt/xov Kal rot? TTepLrrco- 
jLtacrtv, ov jxrjv Sta tovto Set l,rjT€Xv Trdvra evcKa 
TLV05' dXXd TLVcov ovTcov TotoTJTCOj^ €T€pa i^ dvdyKrj^ 
avfJL^aLvei Sta ravra TToXXd. 
"OaoLs ixkv ovv rj rod iJTrarog ovaraoL? vyieivrj 

20 eon Kal rj rod aljiaros (f)vais yXvKela rj els rovr 
aTTOKpivojJievrjy ravra jikv rj Trdfirrav ovk tcr;j^et x^^W 
€7tI rod rjTraros, rj eV rtat (/>Ae^tots-, rj rd jikv rd 8* 
ov. hid Kal rd rjrrara rd rcvv dxoXcov evxpoj Kal 
yXvKepd eoriv (hs eTTiirav eLTretv, Kal rojv ixdvrojv 

25 ;^oAt^v to vtto rfj X'^^fj '^^^ rjrraros yXvKvrarov 
ionv. rcov Se ovvLurafievajv i^ rjrrov KaBapov 
aljxaros rovrov^ iarlv rj x^Xrj rd yivojievov rrepir- 
riOjJLa- ivavriov re ydp rfj rpocf)fj rd Trepirrojjia 
povXerat elvai Kal rw yXvK€i rd rriKpov, Kal re 
at/xa yXvKv rd vyialvov. (fyavepov ovv on ov nvog 

30 eveKa, aAA' drroKadapjxd ioriv rj x^^'^- ^^^ ^^'■ 
XCLpi'^crrara Xeyovcn rojv dpxo-iOJV ol <j)duKovr€s 
airiov elvai rod TrXeio) t,rjv xp^vov rd jirj ex^LV 
XoXrjv, pXeipavres irrl rd pLOJVVxoL Kal rds iXd(f)Ovs' 
ravra ydp dxoXd re Kal ^fj noXvv xpovov. en 8e 
Kal rd jirj icopajjidva utt' eKeivojv on ovk e'xei 

35 xoAtJv, otov S€X(f)ls Kal KafirjXos, Kal ravra rvy- 
xdvei jiaKpo^ia ovra. evXoyov ydp rrjv rod rjiraros 

^ TovTov Peck : tovt* vulg. 


bile elsewhere in the body is a residue or colliques- 
cence, so this bile around the liver is a residue 
and serves no purpose — like the sediment pro- 
duced in the stomach and the intestines. I agree 
that occasionally Nature turns even residues to 
use and advantage, but that is no reason for trying 
to discover a purpose in all of them. The truth is 
that some constituents are present for a definite 
purpose, and then many others are present of 
necessity in consequence of these. 

We may say, then, that in animals whose liver is 
healthy in its composition, and in which the blood 
that supplies the liver is svv'eet, there is either no 
gall-bladder at all by the liver, or else the bile is in 
tiny vessels, or else in some these are present and in 
some not. This is why the livers of gall-bladderless 
animals are, generally, of a good colour and sweet ; 
and in those that have a gall-bladder the part of the 
liver immediately below it is very sweet. But in those 
animals which are formed out of blood which is less 
pure, the bile is the residue of this ; since " residue " 
means that which is the opposite of " food," and 
" bitter " the opposite of " sweet "; and healthy blood 
is sweet. So it is evident that bile exists for no de- 
finite purpose, but is merely an offscouring. So that 
Mas an extremely neat remark which we find made 
by some of the old authors, when they say that if you 
have no gall in you your life will be longer. This 
was a reference to animals with uncloven hoofs and 
to deer, which have no gall-bladder, and are long- 
lived. And also, certain other animals are long-lived, 
such as the dolphin and camel, which, though un- 
observed by them, have no gall-bladder. After all, 
the liver is vital and indispensable for all blooded 

^ 309 


(pvGLV, errLKaipov ovoav /cat avayKaiav Tracrt TOtj 
677 b ivalfJiOLs t,(joois, alriav elvai, ttololv nv ovoav, rod 
t,7Jv iXdrrco rj ttXcloj xpovov. /cat to tovtov [lev rod 
GTrXdyx^ov etvat TTepirroJiia tolovtov, tcov 8' dXXojv 
fjLTjSevos, Kara Xoyov euriv. rij fxev yap /capSta 
tolovtov ovSeva 7TXrjGLdt,eLV olov t€ ;)^u/xov [ovSev 
5 yap Severat Biaiov TrdOos), tcov S' dXXtov ovhkv 
GTTAayxvcxJV avayKaiov ecrrt rot? t,^ots", to o rjTrap 
fiovov SiOTTcp /cat TOVTO avfjL^aivei rrepl avTO pLovov. 


<j>Xeypia rj to vTr6oT7]pL,a ttjs /cotAtaj, TreptTTcu/xa 
etvat, opLOLOJS he hrjXov oVt /cat ;\;oA')7v, /cat pir) 
10 Si,a(f)€peoOaL toZs tottois- 

Kat Trept ftev XoArj?, Sta TtV atTtav Tct />tev cxet 
TO, 8* ou/c e;Y^^ '''^^ C^<^^> etpr^Tat, III. Trept 8e 
pieaevTepiov /cat iiriTrXoov Xolttov etTretv TavTa yap 

iv TO) TOTTCp TOVTO) /Cttt jLteTO, TcDv pLOpiOJV €GTL 

15 "EoTt 8e TO jLtev eVtVAoov u/xT]y TOt? /Ltev OTeap 
exovGL GTeaTcoSrjs, toIs 8e 7npL€Xr]v TTLpLeXcoSrjs- 
TTOta 8* CCTTtv e/caTepa toutcov, e'lprjTaL irpoTepov. 
TJpT-qTai} 8e to eVtVAoov opLOLCO? tols T€ plovokolXlols 
/cat Tot? TToAf/cotAtots' aTTo pi€<jrjs TTJ? KoiXlag /caTO. 
tt^v VTToyeypapLpievrjv olov pacfiijv iiTex^L Se to t€ 

20 AotTTOP' T7^? /cotAtas" /Cat TO Tojv ivTcpcov ttXyjOos 

opLOLOJS TOLS ivaipLOLS, eV T€ TOls TTC^OtS" /Cat TOtS" 
ivvSpOL? t,(pOLS. 

*H )Ltev ow yev€GLS ii dvdyKT]? avpL^alveL TOLavT-q 
Tov popiov TOVTOV ^rjpov yap /cat vypov pLLyf.LaTos 
OeppLaivopievov to €Gxcltov del 8epp,aTa>8es' ytVcTat 

' Tjp/crai SUYZ. 



animals, and so it is quite reasonable to hold that the 
condition of it controls the length of its owner's life. 
And it is equally reasonable to hold that the liver 
produces a residue such as the bile although none of 
the other viscera does so. Take the heart : no such 
humour as bile could possibly come near the heart, 
because the heart cannot withstand any violent 
affection. Of the other viscera none is indispensable 
to an animal, except the liver only, and that is why 
this phenomenon occurs in connexion \\ith the liver 
exclusively. And it would be absurd to say that 
phlegm and the sediment produced by the stomach 
are residues when found in some places but not in 
others ; and clearly the same applies to bile : its 
locality makes no difference. 

We have now spoken of the gall-bladder, and we 
have shown why some animals have it and why some 
have not. III. It remains to speak of the Mesentery 
and of the Omentum. These are in the same region 
and close to the parts we have just described. 

The Omentum is a membrane, formed of suet omentum, 
or lard according to the animal in which it is. (We 
have already stated which animals contain suet and 
which lard.) " Whether the animal has one stomach 
or many, the Omentum is always fastened to the 
middle of the stomach, on the line marked o'n it like a 
seam ; and it covers the rest of the stomach and most 
of the intestines. This is so in all blooded creatures, 
land- and water-animals alike. 

As for the necessary ^ formation of this part, it 

occurs as follows. When a mixture containing solid 

substance and fluid is warmed up, the surface of 

it always becomes skin-like and membranous ; and 

• At 651 a 26 fF. » See Introd. p. 22. 



677 b ^ ^ ^ r V / T / \ / 

/cat u/xevtt»Ses", o Se T07709 ovrog roiavriqs TTArjp-qs 

25 cotI rpo(f)rjs. eVt Se Sia TTu/cvoTT^ra rou vfievog ro 
SirjOoviiei'ov rrjs alfiarcoSovs rpoijyrjg dvayKOLOv 
Xmapov elvai {rovro yap XeTTTorarov) Kal 8td rrjv 
depfjLOTTjra ttjv irepl rov tottov avfJiTreTTOfJievoy avn 
oapKojhovs Kal at/xarcoSou? Gvardorecos areap yi- 
veoBai Kal 77tjLteArJv. r] [xev ovv yeveais rod cxrt- 

30 ttXoov Gvpi^aiveL Kara rov \6yov rovrov, Kara- 
Xprjrai 8' rj (jyvoLs avro) irpos rrjv evTreiptav rijs 
Tpocfirjs, oTTios paov Trerrry Kal ddrrov rd t,a)a Trjv 
Tpo(j>-qv' TO /Ltev yap depfiov TreTTTiKov, to 8e ttlov 
Oepjjiov, TO 8' eTTLTrXoov ttZov. Kal hid rovr airo 
[xeGT]? rjprrjTai^ rrjs KocXlas, on ro erreKeiva^ fiepos 

35 orvjJLTTerreL ro TrapaKelfievov rjirap. Kal rrepl (jl€V 
rod eTTLTrXoov e'iprjrai. 

IV. To 8e KaXovjJLevov fxeaevrepLov eom fxev vfJirjv, 
StaretVet 8e avvex^? diro rrjs rcjv ivrepojv rrapa- 

678 a Tacrecos" et? rrjV (jtXi^a rrjv fieydXrjv Kal rrjv dopmjv, 

TrXrjpe^ ov (jiXe^cbv ttoAAcov Kal ttvkvcov, at reivovoiv 
diTo raJv ivrepcov et? re rrjv [xeydXiqv cfyXe^a Kal rrjv 
doprriv. rr]v [xev ovv yeveaiv ef dvdyKTjs ovoav 
5 €vpi^(TOfjL€V ofioLOJs roL£ aAAot? pioploLs^' Std TtVa 8' 
alriav VTrdpxei rols ivalfioLs, (jiavepov eoriv em- 
oKOTTovoiv. inel ydp dvayKalov rd ^cpa rpo(f)7]v 
Xapi^dveiv dvpadev, Kal ttoXlv Ik ravrrjg yiveodai 
rr)v iaxdrrjv rpocfyrjv, i^ rj(; rjSr] 8ta8t8oTat ets" ret 
p-opia [rovro Se rot? jLtev dvaipLois dvcovvfiov, rols 8' 

1 ^pKrm EPSUYZ. 
^ €TTiKCiya Peck : en' eKCivo vulg. 
^ <ToiouTois> fiopiois Ogle : [fio/3iots] vfxeai Piatt. 


the place \vhere the Omentum is is full of nutriment 
of this very sort. Furthermore, owing to the thick- 
ness of the membrane, that portion of the blood-like 
nutriment which percolates through it must of neces- 
sity be fatty, because that is the finest in texture ; 
and then owing to the heat in that part it will be 
concocted and so become suet or lard instead of some 
fleshy or blood-like substance. This, then, is the way 
in which the formation of the Omentum occurs. 
Nature, however, turns the Omentum to advantage in 
the concoction of the food, so as to enable the animal 
to concoct its food more easily and more quickly ; 
for the Omentum is fat ; fat things are hot, and hot 
things aid concoction. For this reason, too, the 
Omentum is fastened to the middle of the stomach ; 
since as regards that part of the stomach which is 
beyond, the liver which is close by it assists it in 
concoction. So much for the Omentum. 

IV. What is called the Mesentery is also a mem- Mesentery. 
brane ; and it extends continuously from the line of 
extension of the intestines as far as the Great Blood- 
vessel and the Aorta. It is full of blood-vessels, 
which are many in number and closely packed 
together ; and they extend from the intestines as 
far as the Great Blood-vessel and the Aorta. We 
shall find, as with the other parts, that the develop- 
ment and formation of the Mesentery is the result 
o^ necessity . As for its purpose in the blooded animals, 
that is clear enough to those who consider. Animals 
must of necessity take in nutriment from without ; 
and, again, out of this the " ultimate nutriment " 
has to be made ; and from this store the supply is 
distributed directly to the parts of the body. (In 
blooded animals this is called blood ; there is no 



678a ^ ^ 

10 evalfjiOLg at/xa /caAetrat), Set rt etvai St* ov els ras 
(f)X€^ag eK rrjs KoiXias olov Sta pit^wv TTopevaerai r) 
rpo(f)rj. TO. {lev ovv t^vra rcts" pt^a? ^X^^ ^^^ '^V^ YV^ 
[iKeWev yap XafJLJSdvei Tr]v Tpo0i]v), rot? Se t^cLoig r) 
KOiAia Kal Tj rcov ivrepcov SvvajjLLs yrj Iutlv, i^ rjg 
Set Xafi^dveiv rr^v Tpo(j)i]v SioTrep rj rov [JLeaev- 

16 replov (f)VGLS iartv, olov pittas e^ovaa ras St' avrrjs^ 
<f)Xe^as. ov pLcv ovv eVe/ca to fjLecevrepiov ecrrtv, 
ctprjraL' rtVaSe rporrov Aa/x/3avet rrjv Tpo(f)'^v, Kal 
7TCOS elGepxerai Sta rojv (fyXeftojv diro rrjs icrxdrr]?^ 
rpO(f>r\s els rd piopia Trdvra^ to StaStSojuevov etV rds 
^Xe^as, iv rots nepl rrjv yevecnv rwv ^cocov Xex^ij- 

20 aerai Kal Tr]v rpocji-qv. 

To, jLtev ovv evaijia rcov t,ix)OJV ttcos e;\;€t fi^xpi' tcDv 
StcuptCTjLteVcov jJLopLCov, Kal Sta rivas alrias, e'lprjraL' 
nepl Se rcov els rrjv yeveaiv avvreXovvrcov , ols hoKel 
Sta^epetv to OijXv rov dppevos, ixdp-evov ptev eon 

25 Kal XoiTTOV rcov elpr]ii€vcov aAA' errethj] irepl yeve- 
aecos XeKreov, dppLorrov earl Kal irepl rovrcov iv rfj 
TTepl eKeivcov decopla SieXOeiV. 

V. To, Se KaXovpLeva ptaXdKia /cat [laXaKoarpaKa 
noXXrjv exec Trpos ravra SLacf}opd.v evOvs yap rrjv 
rcov GTrXdyxvcov aTrauav ovk exei (f>VGLv. ojioicos S' 
80 ouSe rcov dXXcov dvaipLcov ovSev. eon Se Suo yevq 
XoLird rcov dvalpicov, rd r oorpaKoSeppLa Kal ro rcov 
ivropLcov yevos. ef ov yap ovveorrjKev r) rcov 
airXdyxvcov (f)VOis, ovhev rovrcov exei at/xa, Sta to 

^ avTTJg Peck : avTTJs vulg. 
• ioxo-rrjs Peck : eiaiovcrqs vulg. 
' iravra Ogle : ravra vulg. : om. Z. 


special name for it in the others.) Now there must 
be some passage or passages (as it might be roots) 
through which this nutriment shall pass from the 
stomach to the blood-vessels. The roots of plants 
are of course in the ground, because that is the 
source from which plants get their nutriment. For 
an animal, the stomach and the intestines correspond 
to the ground, the place from which the nutriment 
has to be derived. And the Mesentery exists to 
contain these vessels, corresponding to roots ; they 
pass through the inside of it. This completes my 
account of its Final Cause. As for the means by 
which the nutriment is taken up, and the way in 
which that portion of the ultimate nutriment which 
is distributed into the blood-vessels reaches all the 
parts of the body through them, these points will 
be dealt with in the treatises on the Generation of 
Animals and on Nutrition. 

I have now described the blooded animals as far 
as concerns the parts that have been dealt with, and 
also the causes that are responsible. It remains, 
and would follow after this, to speak of the organs 
of generation, by which male and female are dis- 
tinguished. But as we shall have to deal with 
generation itself, it is more appropriate to speak of 
these organs in our consideration of that subject. 

V. The animals called Cephalopods and Crustacea internal 
are very different from the blooded ones. First of all, bloSless 
they have no visceral structure at all. This is true animals. 
of all the bloodless creatures, in which are included 
beside Cephalopods and Crustacea two other groups, 
the Testacea and the Insects. This is because none 
of them has blood, which is the material out of which 

L 315 


678a ^ ^ ^ 

rrjg ovGiag avrojv elvat tl tolovtov Trddos [avrrjs]^' 

on yap eon ra fiev eVat/xa to. 8' aVat^a, iv ro) 

85 Xoycp ivvTrdp^ei rco opit^ovn rrjv ovoiav avTcov. en 

S' cov eveKev exovcn ra OTrXdyx^cL to. evaifxa rcbv 

^cpcov, ovSev lUTrdp^ei roZs tolovtols' ovre yap 

678 b ^Ae/Sa? exovoLV ovre Kvonv ovr dvairveovoiv , dX\d 

[jLovov dvayKalov e;^etv avroX? to dvdXoyov rfj Kap- 

Slo,' to yap alaOrjnKov ^VXV^ '^'^^ '^^ "^V^ ^^t]? ctt- 

nov (ivy^ ^PXfl '^^^^ '^^^ fiopLCOv /cat rov awpLarog 

VTrap^ei Trdoi rols ^coot?. ra he irpo? rrjv Tpo(f)r]v 

5 flop La ex^i Kal ravra e^ dvdyKrjs Trdvra' ol he 

rpoTTOi hLa<j)epovGi hid rovg tottovs ev of? Xafx- 

^dvOVGl TTjV Tpo(j)iqv. 

"YjXovgi he TO. fiev fiaXdKLa rrepl to KaXovpevov 
OTopia hijo ohovras, Kal ev rep orop^an dvn yXojr- 
T7]s aapKcohes n, S Kpivovai rrjv ev rols ehearols 
r]hovriv. opLolcjog he Kal ra pbaXaKourpaKa tovtols 
10 TOWS' TTpcjTOVs oSovTa? e;Yet Kal to dvdXoyov ttj 
yXcoTTT) aapKoJhes. eTi he Kal to. ouTpaKoheppLa 
rravTa to tolovtov ex^L p.6pLOV Sta ttjv avT'qv aWlav 
TOL£ evaipoLs, TTpos rrjv ttJs" Tpo(j)rJ5 aiodrjOLV. 
opLOLOJ? he Kal Ta evTopLa Ta pLev ttjv e^Lovoav em- 


15 yevo£ Kal to tojv pLVLcov, ojarrep eip-qTai Kal irpo- 
Tepov ooa he pnq eaTLV epLTTpoadoKevTpa, ev tw 
GTopiaTL ex^t- TO tolovtov pLopLov, olov TO Tchv 
jxvppLTjKOJV yevos Kal el tl tolovtov eTepov. oSdvTa? 
he TO, pLev ex^i' toutcov, aAAotorepous" he, Kaddrrep 
^ avTTjg socliisi. ' ev supplevit Th. 

" See Introduction, pp. 26 ff. 

^ These teeth are the two halves of what might be com- 
pared to a beak. 


viscera are made ; and the reason for this is that a 
condition of this sort is part of their being : the fact 
that some animals are blooded and some bloodless 
will be found to be included in the logos '^ which 
defines their being. Further, we shall see that none 
of those purposes for whose sake blooded animals 
have viscera operate in these other creatures : they 
have no blood-vessels and no bladder, they do not 
breathe : the only organ they must necessarily have 
is the counterpart of the heart, since the sensitive 
part of the Soul and the original cause of life is always 
situated in some place which rules the body and its 
parts. Also, they all have of necessity the parts 
adapted for dealing with food and nutrition ; but the 
manner of these varies according to the places where 
they take their food. 

The Cephalopods have two teeth around what is 
called their mouth ^ ; and inside the mouth, instead of 
a tongue, they have a fleshy object, by means of 
which they discriminate the savour of things to eat. 
Likewise, the Crustacea have these front teeth and 
the fleshy counterpart of the tongue. The Testacea 
all have this latter part, too, for the same reason that 
blooded animals have a tongue, viz. to perceive the 
taste of the food they eat. Similarly, too, the Insects 
have, some of them, a proboscis which comes out 
from the mouth, as with the Bees and Flies (this has 
been mentioned earlier '') ; and the ones which have no 
sharp protrusion in front have a part such as this 
inside the mouth, as Ants, and the like. Some of 
these creatures have teeth, though somewhat differ- 
ent from ordinary teeth (as the Flies,'^ and Bees) ; 

" At 661 a 21 ; cf. Hist. An. 528 b 28. 
* Or " Ants " (translating Meyer's emendation). 



678 b ^ 

TO T€ Tojv iJLVLcov^ Kat TO Tcov fj-eXiTTcov yivos y ra 8' 

20 ovK €X€i, oaa vypa -x^prir ai rfj rpo(f)fj' ttoXXol yap 
TOJV ivTOfxojv ov Tpo(j)r]s ex^f' X^P^^ rovs ohovras 
dAA' dXKrj?. 

Tcbv 8' oGTpaKohepfjLOJV ra {xcv, ajoirep iXex^l ^^^^ 
iv Tols Kar dpxoLS XoyoLs, rrjv Ka\ovp.evr]v e^ei 
yXwTrav laxvpdv, ol he koxXoi /cat dSovra? Suo, 

25 KaOdnep rd ixaXaKoorpaKa. fierd Se to arofia roZs 
fiaXaKLOL? eurl oTOjiaxos piaKpos, tovtov S' exo- 
fievos TrpoXo^os olog irep tols opviGiv, elra avvexy]? 
KOiXla, Kal ravrrjg ixopLevov evrepov dirXovv piexpi 
rrj? i^oSov. rats /xev ovv o-qiriais koL tols ttoAu- 
7TOGLV djU-ota Kat TOt? GXT^P'O.crt' Kal Tjj d(f)fj Ta irepl 

30 TT^y KoiXiav Tat? he KaAou/xeVat? TevdiuL hvo p.ev 
opLOLOJS at KotAttuSet? elalv VTTohoxciL, tJttov he 
TTpoXo^ojhrjs Tj eTepa, Kal TOt? CT;(rJ/xaCTtv eKeivcxJV 
hLa(f)epovGL Std to Kal to cco/xa Trdv e/c {laXaKOj- 
repag ovveoTdvaL oapKos. 

TavTa 8' €;^et tci [lopLa tovtov tov Tponov 8td 
TTjv avTTjv aLTLav wGTTep Kal OL opvLdes' ovhe yap 

35 TOVTCx)v ovhev evhex^TaL XeaiveLv ttjv Tpo(f)-^v, hLoirep 
6 TTpoXo^os eo-Tt TTpd Trjs AcotAta?. 

Ilpds ^o-qOeLav he Kal oojTrjpiav ex^L TavTa tov 

679 a KaXovpLevov OoXov ev ;)^tTtuvt VfievojheL 7TpoG7T€(f)v- 

KOTL^ TTJV e^ohov exovTL Kal TO Trepas fjTrep dcj^LaGL 
TO TTepLTTCop^a TTjS KotAta? KaTa TOV KaXovpievov 
avXov ovTOS 8' eGTlv ev toZs vtttlols. ex^L p.ev ovv 
6 ndvTa TO, /xaAd/cta tovto to p.6pLov t8tov, /xdAtCTTa 
8* 7] GrjTTLa Kal irXelGTOV OTav ydp (f)o^rj6a)GL Kal 
^ liviajv^ [xvicov l,a>ov EY : fivpfii^Kcov Meyer. 

* 7Tp0O7T€<f>VK6Tl Oglc I npoa7T€<f>VK6Ta VUgl. 



others have no teeth at all : these are the creatures 
whose food is fluid. Indeed, in many of the insects 
the purpose of the teeth is not mastication of food at 
all, but for use as weapons. 

Of the Testacea, as we stated in the opening treat- 
ise," some have a very strong tongue (so-called) ; and 
the Sea-snails actually have two teeth as well, like the 
Crustacea. In the Cephalopods there is a long gullet 
next after the mouth, and contiguous to that is a 
crop like a bird's. Continuous with this is the 
stomach, then immediately the intestine, which is 
simple and reaches to the vent. In the Sepias and 
Octopuses these parts round the stomach are similar 
both in shape and in consistency. The creatures called 
Calamaries, like the others, have the two gastric 
reC'Cptacles,^ but the first of them is less like a crop ; 
and they differ in shape from the organs of the 
previous classes, and that is because their bodies are 
composed of softer flesh throughout. 

These creatures have these parts arranged in this 
way for the same reason that birds have them: they, 
like birds, are unable to grind down their food ; hence 
the crop is placed before the stomach. 

The Cephalopods, for the sake of self-defence and 
self-preservation, have what is called their Ink. This 
is contained in a membranous bag which is attached 
to the body, and comes to an end in an outlet where 
the residue from the stomach is discharged by the so- 
called funnel. This is on the under side of the body. 
All the Cephalopods have this peculiar part, but it is 
most remarkable in the Sepia, as well as the largest 
in size. When the Sepia is frightened and in terror, 

" At Hist. An. 528 b 30 ff. 
• Viz. the crop and the stomach. 

' 319 


679 a ^ 

heiaojGiv, olov (j^pdyjia irpo rod acofiaros TTOiovvrat 

Ti]v rod vypov [leXaviav /cat OoXcjoglv. at [lev ovv 

TevOiSes Koi TToXvTTohes exovcnv avcodev rov doXov 

€7t\ rfj {jlvtlSl ijLaXXov, -q Se crr^TTta npos rfj kolXlo. 

10 Kara)' TrXeio) yap e^^i- Stct to ;^p7]cr^at fidXXov. 
TOVTO 8* avTjj GviJ,^aLV€L Sto, TO TTpooyeiov [Jiev elvai 
Tov ^iov avTrfS, p-r] ^X^'-^ ^' dXX7]v ^orjOeLav, wanep 
6 TToXvTTOvs TCtS" TrXeKTO-vas e;)(£t XPV^^H-^^^ ^^'' '^V^ 
rod ;!^paj/xaTOS' pLeTa^oX-qv, 'q (jvpL^alveL avTO), 
coGirep Kol Tj Tou doXov TTpoeGis, 8ta SetAtav. t^ Se 

16 revdlg TTeXdyLov Igtl tovtojv pLOVOV. irXeioj p.ev ovv 
€X€L Tj G7]7Tia TTapoL TOVTO TOV doXov, KaTOjOev Sc 8ta 
TO TrXeioj- pahiov yap TTpoteGdat Kal TToppcjdev cltto 
TOV TrXeiovos. ytVerat Se [o doX6s\^ KaOajrep rotS" 


yetoSes", ovtco Kal tovtols 6 OoXos Std to jitT^Se TauT* 
20 e;^etv KUOTtv OLTTOKpLveTai yap to yecoSioTaTOV els 
avTOVy Kal TTJ G-qiria TrXeiGTOv Sta to TrAetOTOV ex^iv 
yecoSes". Giqp.e'iov Se to GrjTTLOv tolovtov 6v tovto 
yap 6 /Ltey ttoXvttov^ ovk e;^et, at Se Tevdihes X^^' 
SpcoSes" Kal XeiTTov. (St' tjv S* alriav to, pev ovk 
ex^t- TO. S' e;^et, Kat ttolov tl tovtojv ex^t eKaTepov, 
25 ^ Kvaipiojv S' ovTOJV Kal Sta tovto KaT€ipvypL€va>v 
Kal (f)o^r)TLKa)v, coGirep iviois oTav Setoojotv rj 
KOiXia TapctTTeTat, TOts" S' eV tt^s" KVGTews pel 


^ [6 doXos] seclusi : o oin. P. 
^ eiprjTat, irpoTcpov P. 

** The nnjtis, which is the same as the mecon, is an excretory 
organ, and corresponds to the Uver. See below, 679 b 11, 

" Cf. above, 67G a 32. 


it produces this blackness and muddiness in the 
water, as it were a shield held in front of the body. 
Now the Calamaries and Octopuses have this ink-bag 
in the upper region of the body, quite near the mytis'^', 
whereas in the Sepia it is lower down, against the 
stomach, since it has a larger supply because it uses 
it more. This circumstance is due (1) to its living 
near the land and (2) to its having no other means of 
defence — nothing like the Octopus, for instance, which 
has its twining feet, which are useful for this purpose ; 
it can also change its colour, and it does so (just as 
the Sepia emits its ink) when put in fear. Of all 
these, only the Calamary lives well out at sea and gets 
protection thereby. Hence, compared with it, the 
Sepia has a larger supply of ink ; and because this is 
larger, it is lower in the body, as it is easy for it to be 
emitted even to a considerable distance when the 
supply is great. The ink is earthy in its nature, like 
the white deposit on the excrement of birds, and it is 
produced by these creatures for the same reason — 
they, like birds, have no urinary bladder ^ ; so the 
earthiest matter is excreted into this ink, especially 
in the Sepia, for the Sepia contains an exceptionally 
large amount of earthy matter. An indication of 
this is its bone, which is earthy. The Octopuses do 
not have this bone, and in the Calamary it is cartila- 
ginous and slight. (We have said why some of these 
animals have this part and why some have not, and 
what in each case its character is.) 

These animals, as they have no blood, are cold and 
liable to take fright. While in some other animals 
fear causes a disturbance of the stomach, and in some 
the discharge of residue from the bladder, in these 
creatures its effect is to make them discharge their 

' 321 


679a ^ ^ 

di'dyKrjg d^Uvai Sta heiXiav, cjOTrep €K Kvarcojg 

Tols inovpovGLV, rj Se (^vgls df.La ro) tolovtco xrcpir- 

80 Tcofiart Karaxp'TJTai npog f^orjdcLav Kal GcorrjpLav 


"K^ovGL Se Kal rd ptaXaKoarpaKa, rd re Kapa- 
^oclStj Kal ol KapKLVOL, Svo pikv oSovra? tov<^ 
TTpcorovs, Kal fiera^v ttjv odpKa rr]v yXcjaaoeLSrj, 
(jjGTTep e'uprjraL Kal Trporepov, eu^u? 8* ixdp^evov rod 
GTopLaros GTopiaxov puKpdv /caret fxeyeOos rwv 
35 Gcopbdrajv [rd ju-etjco 77^0? to, eAarrco]^- rovrov he 
KoiXiav €xop€vr]v, ecf)* tj^ ol re Kdpa^oi Kal evioi 
Tojv KapKLvojv ohovrag exovGiv irepov? Sid to tovs 
679 b dvco jjLTj hiaipelv txravcos", dird he rrj? /cotAta? 'ivrepov 
drrXovv /car' evOv p-^xpi- Trpds ttjv e^ohov rod 

''E;^et 8e Kal tojv oGrpaKoSeppcov eKaGTOv ravra 
rd fJLopiay rd /xev Sir]pdpa>pL€va jjLaXXov rd 8' rjrrov 
iv 8e rot? pLeit^oGi hiahiqXorepd CGriv e/cacrra rov- 
6 ro}v. ol /xev ovv koxXoi kol dSovra? exovGi gkXt]- 
povs Kol olets", a)G7T€p e'iprjrai rrporepov, Kal rd 
jxera^v GapKOjSeg op^olcog rols paXaKiois Kal /LtaAa- 
KOGrpaKOiSy Kal rrjv Trpo^oGKuSa, Kaddnep eLpr]raL, 
fiera^v Kevrpov Kal yXojrrrjs, rod 8e Gropiarog 
ixdpi€VOV otov opvidcohri rivd npoXo^ov, rovrov 8' 
10 ex6pi€Vov GropLaxov rovrov 8' ex^rai rj KoiXia, iv fj 
T) KaXovpLevT] fjL-qKOJV, dcji* ^? Gvvex^S eGnv evrepov 
dnX-qv r7]v dpxr]v €XOV dno rrjs pLTQKOJVos' €GrL ydp 
iv TTaGL rot? oGrpaK-qpols TTcpirrcopLa rovro ro 
fidXiora hoKovv elvat ihwhipiov. e;;^et 8' opioiajs rep 

* seclusit Rackham. 


ink ; and though this is an effect due to necessity, 
hke the discharge of urine in the others, yet Nature 
makes good use of this residue at the same time 
for the animal's defence and preservation. 

The Crustacea as well, that is, both the Crabs and 
the Caraboids, have the two front teeth, and between 
the teeth they have the tongue-like flesh, as has 
already been stated " ; and immediately next to the 
mouth they have a gullet which is quite small com- 
pared with the animal's size ; and immediately after 
that the stomach ; and on this the Carabi and some 
of the Crabs have another set of teeth, since the 
upper ones do not masticate the food sufficiently. 
From the stomach a simply formed intestine runs 
straight to the vent where residues are discharged. 

These parts are present in every one of the Testacea 
as well, more distinct in some, less in others. They 
are more clearly marked in the larger animals. 
Take the Sea-snails. These have (1) as stated al- 
ready, the teeth, which are hard and sharp, (2) the 
fleshy object in between them, similarly to the 
Crustacea and Cephalopods ; (3) the proboscis, as 
already mentioned,^ something between a sting and 
a tongue ; (4) immediately after the mouth is a sort 
of bird's crop, and (5) after that the gullet ; (6) con- 
tinuous with that is the stomach, and (7) in the 
stomach is what is known as the mecon'^', and (8) at- 
taching to this is an intestine : this intestine begins 
directly from the mecon. This residue (the mecon) 
appears to be the most tasty piece in all the Testacea. 
The other creatures that have spiral shells (e.g. the 

« At 678 b 10. 

" At 661 a 15 ff. 

* The hepatopancreas or liver ; see above, 679 a 9. 

l2 323 


679 b ^ 

15 Kox^cp /cat rdXXa ra arpofJil^coSr], olov 7Topcf)vpai 

Kal KrjpvKeg. 

"Ecrrt 8e yeurj Kal e'lSrj ttoXXol rtuv oarpaKO- 

Sepjjicov TOL jLtev yap GTpoji^coSrj ioTiv, wGTrep ra 

vvv elpTjiievay ra he ScOvpa, ra Se fxovodvpa. rpoTTOV 

8e rtva Kal ra arpojjL^coS'q ScOvpoig eoiKev ex^L yap 

CTnTTTuy/xar' enl rep (pavepcp rrjg aapKos rravra ra 

20 TOiavra e/c yeverrjs, olou at re 7Top(f)vpaL Kal 
KTipvKes Kal OL vrjpe'lraL Kal irdv ro roiovrov yevos, 
77/30? ^oi]d eiav f) yap firj TTpo^e^XrjraL ro oorpaKov, 
paSiov ravrr) ^XaTrreaOai vtto rojv OvpaOev irpoG- 
TTLTTrovrajv. ra [lev ovv jjiovoOvpa Sta to rrpocr- 
7r€(f)VK€vaL Gw^eraL rco v paves ^x^tv ro oorpaKov, 

25 Kal yiverai aXXorpioj (jypdypiari rporrov rivd St- 
dvpov, olov at KaXovfJLevai XeirdSes' ra Se SiOvpa, 
OLOV Kreves Kal [xveg, rco ovvdyeiv, rd Se GrpopL^ajht] 
Tovrcp rep eTTiKaXvpLpiari, cjorrep SlOvpa ycvojjLeva eK 
fiovodvpojv. 6 S' exlvo? fidXiora ndvrcov dXewpdv 
€X€L' kvkXco yap ro oorpaKov Gvvr]pe(f)e? Kal K€' 

80 x'^P^KOjpievov rats aKdvOaig. lSlov S' ex^t, rcov 
OGrpaKoSepfJLOJV rovro, KaOdnep etprjraL nporepov. 

TcDp' 8e fiaXaKOGrpaKCxJV Kal rcJov oGrpaKoSeppLwv 
GvveGrrjKev rj ^vais rols pLaXaKiois avrt/cet/xeVcos"* 
rot? /xev yap e^oj ro GapKcoSe?, rols S' ivros, eKros 
8e ro yeojSes. 6 8' exlvos ovhev ex^i GapKcoSes. 

35 Oavra /xev ovv ex^t^, Kaddrrep e'lp-qrai, Kal rdXXa 
rd oorpaKohepixa Grojjia re Kal ro yXcurroeiSes Kal 
KoiXiav Kal rod Trepirrcoixaros rrjv e^ohov, hia^epei 

* The operculum, 


Purpuras and the Whelks) are similar to the Sea- 
snails in structure. 

There are very many genera and species of Tes- 
tacea. Some have spiral shells, like the ones just 
mentioned ; some are bivalves, some univalves. In 
a way, the spiral shells resemble the bivalves, as they 
have, all of them, from birth, a covering ° over the 
exposed part of their flesh, e.g. the Purpuras, the 
Whelks, the Nerites, and the whole tribe of them. 
This covering serves as a protection ; for in any place 
where the animal has no shell to protect it, it could 
quite easily be injured by the impact of external 
objects. The univalves' means of preservation is this : 
they cling to some object, and have their shell on the 
upper side ; so they become in a way bivalves in 
virtue of the borrowed protection afforded by the 
object to which they cling. Example, the Limpets. 
The bivalves proper (e.g. Scallops and Mussels) get 
their protection by closing themselves up ; the spiral- 
shelled creatures by the covering I mentioned, which, 
as it were, turns them from univalves into bivalves. 
The Sea-urchin has a better defence system than any 
of them : he has a good thick shell all round him, 
fortified with a palisade of spines. As I stated pre- 
viously, the Sea-urchin is the only one of the Testacea 
which possesses this peculiarity. 

The natural structure of the Crustacea and of the 
Testacea is the reverse of that of the Cephalopods. 
The latter have their fleshy part outside, the 
have the earthy part outside and the fleshy inside. 
The Sea-urchin, however, has no fleshy part at all. 

All these parts, as described — mouth, tongue-like 
object, stomach, vent for the residue — are present 
in the rest of the Testacea too, but they differ in 

, 325 


680 a he Trj Oeoet Kal rot? fJieyeOeaLV. ov Se rponov e^ct 
Tovrojv €KaaTov, e/c re tcjv IcrropLCJV rwv nepl ra 
^cpa decopeLuOoj Kal eV tojv dvaTOfJicov' ra fiev yap 
Toj Xoycp TO. Se Trpo? rrjv oipiv avrojv Gaffyrjvl^eiv 8et 

'IStto? S* exovGL Tcov 6orpaKohepp.OL>v 61 r e-)(lvoi 
6 Kal TO rojv KaXovfievcov ttjOvcov yevos. exovGL 8* ol 
ix^voL oSovras {jlev irevre Kal jxera^v to oapKchhes , 
oirep €7rl Trdvrojv icrrl rtov elpTjjjLevojVy exppievov he 
rovrov oropiaxoVy dno he tovtov ttjv KOiXiav els 
TToAAo, hiTjp'qpeviqv, warrepavel ttoXXols rod t,a)ov 
KoiXias exovTos. Kex(JopL<jf.LevaL p.ev yap elcn Kal 

10 TrX-qpeis TreptTraj/xaro?, e^ eVos" S' TJpTrjvraL rod 
GTopLaxov Kal reXevTcocn npos pbtav e^ohov ttjv rod 
TTepirrojpLaTOS. vapd he r-qv KoiXiav aapKajhes pLev 
ovhev exovGLV, wdTrep e'ipiqrai, rd he KaXovpieva cod 
TrXeicu rdv dpidpidv ev u/xeVt ;)(6opt? eKaurov, Kal 
kvkXo) dno rod uroptarog pLeXav* drra hteaTrappeva 

15 Xvhr]v, dvojvvpLa. ovrcov he irXeLovcov yevcbv [ov ydp 
ev ethog rcov ex^vcov Trdvrojv eori) rrdvres piev ep^oucrt 
ravra rd pLopLa, dAA' ovk eScoSi/xa Trdvreg rd 
KaXovpieva cod, Kal puKpd rrdpirrav e^cxj rcov im- 
TToXa^ovrcxjv. oXcos he rovro Kal nepl rdAAa avpL- 

20 ^e^rjKe rd oorpaKoheppia' Kal ydp at crdpKes ovx 
opLOicxJS ehajhipLoi TrdvTCov, Kal rd TTepirrcjopia, rj 
KaXovpLcvq pLTjKOJv, evLCxJV piev ehcohipos evicnv S' ovk 
ihcohipios. eon he rols orpopi^coheGiv ev rfj eXiKj} 

" Hist. An. 52Sh 10 ff. 

* This seems to imply that diagrams or illustrations accom- 
panied the treatises. 

* These form what is compared to a lantern at Hist. An. 
531 a 5, hence the name, " lantern of Aristotle." 



their position and size. For the details of these, con- 
sult the Researches upon Animals^ and the Dissections. 
Some points are better explained by inspection'' than 
in words. 

The Sea-urchin and the genus of Ascidians are 
peculiar among the Testacea. The Sea-urchin has 
five teeth,^ and between them it has the fleshy sub- 
stance (the same as in all the above-mentioned 
creatures) ; after that, the gullet, after that, the 
stomach, which is divided into several compartments, 
so that the animal seems to have several stomachs. 
But although they are separated from each other and 
are full of residue, they all spring from the gullet and 
they all terminate in the residual vent. Apart from 
the stomach, these creatures contain no fleshy sub- 
stance, as I have said. They have, however, what 
are called ova ^ ; there are several of them and each 
is in a separate membrane ; and scattered at random 
round the body, beginning from the mouth, are 
certain black objects,^ which have no name. There 
are several kinds of Sea-urchin, and in all of them 
these parts are present. Not all, however, have 
edible^ ova, and, except in the common^ varieties, 
they are quite small. There is a similar distinction 
among the other Testacea : the flesh is not equally 
edible in all of them, and in some of them the residue 
(the so-called mecon) is edible, in others not. In the 
spiral shells, the mecon is in the spiral, in univalves 

** These are really ovaries (or testes) : gonads. 

* These may be the ambulacral vesicles, but the identifica- 
tion is not certain. 

' See the story of the Spartan in Athenaeus iii. 41. 

' The word translated " common " may mean " living near 
the surface." 

' S27 


680 a ^ 

Tovroy TOLS 8e fiovoOupocg iv rco ttvBixIvl, oiov raZs 
XeTrdcTLy TOtS" 3e hidvpois rrpos rfj Gvva(f)fj' to 8* wov 

25 KoXovpLevov iv rots he^ioZs, iv he roZs eirl Odrepa r) 
€^ohos rod 7T€pLTT(jL)fiaTOs Tots" Sidvpoig. KoXeZrai 
8* (hov ovK 6pda)s V7t6 tcjv KaXovvrcjJV rovro yap 
€GTiv olov Tols ivaljjLOLs, OTav €v9r]v6jaLv, Tj TTLorrjs. 
Sio Kal yiverai /caret rovrovs rovs Kaipovs rod 
evtavTov ev ols evOrjvovuLVy ev re to) eapi Kal 
IxeroTTOjpcp' ev yap toj ipv)(^ei Kal rals aXeais tto- 

30 vovGL TTavra rd oarpaKoSepfiay Kal (f)€p€LV ov 
8uyavTat rag virepj^oXas . or^pLelov 8e to GVfJL^alvov 
€7Ti Tcov e-x^ivojv €vdv£ T€ ydp yivofievoL exovGi Kal 
iv rals 7TavGeXi]voL£ fidXXov, ov 8ta to vefieGOaL 
Kaddirep rives oiovrai fiaXXov, dXXd 8ta ro dXeeivo- 
repas etvau rag vvKrag Sid to (jichs rrjs GeXrjvqs. 

35 SvGpiya ydp ovra Sid ro dvaifxa elvau Seovrai dXeas. 
Slo Kal iv rep depei fiaXXov Travra^ov evdiqvovGiv, 
esObTrAi^i^ OL iv to) Ylvppaio) evpirrcp' iKelvoi 8' ou;)^ 
rjrrov rod ;)^et/xtDyo?- a'iriov 8e ro vofjirj? evrropelv 
rore [xaXXov, aTroXenrovrcov tcov lyjdvojv rovs ro- 
TTOVS /caTO, ravTTjv rrjv wpav. 

*'E;^ouo't 8' ol i)(ivoi irdvres toa Te rw dpiOpLcp to, 

6 cpa Kat TTepiTTd' nevTe ydp exovGLV, togovtovs 8e 

/cat Tovs oSovTas Kal Tds KoiXlas. aiTiov 8* on to 

d)6v iGTL, KaOaTTep e'iprjTai irpoTepov, ovk (hov dXXd 

rod t^wov evrpo<j)ia. yiveTai he tovto inl ddrepa 

" This is true of the sea-urchins in the Red Sea, though not 
of the Mediterranean ones. The former have a cycle corre- 
sponding exactly to that of the moon. The five roeSi ovaries, or 
testes are large and swollen during the week preceding each 
of the summer full moons, and tlie spawning of the eggs 
takes place during the few days before and after full moon. 
For a most interesting discussion of this and kindred matters 


(like limpets) it is in the tip ; in bivalves it is near 
the hinge. In the bivalves the so-called ovum is on 
the right-hand side, and the residual vent on the left. 
" Ovum " is a misnomer ; actually it corresponds to 
fat in blooded creatures when they are in good con- 
dition ; and that is why it appears only in spring and 
autumn, which are the seasons when they are in good 
condition. In great cold and great heat all the 
Testacea are hard put to it ; they cannot endure in- 
ordinate temperatures. The behaviour of the Sea- 
urchins is a good illustration of this : they have ova 
in them as soon as they are born, and at the time of 
full moon these increase in size " ; and this is not, as 
some think, because the creatures eat more then, but 
because the nights are warmer owing to the moon- 
hght. These creatures have need of the heat because 
they are bloodless and therefore adversely affected 
by cold. That is why they are in better condition 
during the summer, and this is true of them in all 
localities except the strait of Pyrrha,^ where they 
flourish equally well in winter, and the reason for this 
is that in winter they have a more plentiful supply of 
foodstuff, due to the fish leaving the district at that 

The Sea-urchins all have the same number of ova — 
an odd number, five, identical with the number of 
teeth and stomachs which they have. This is ac- 
counted for by the " ovum " not being really an ovum 
(as I said before) but simply a result of good nourish- 
ment. The " ovum " is found in Oysters too, though 

see H. M. Fox, Selene, especially pp. 35 fF., and id. Proc. 
Roy. Soc. B., 1923, 95, 523. 

" In Lesbos, leading to the lagoon, one of Aristotle's 
favourite hunting-grounds : see Hist. An. 544 a 21 (sea- 
urchin), 548 a 9, 603 a 21, 621 b 12. Cf. Gen. An. 763 b 2. 

' 329 


680 b 

[Movov €v roZs oorpeois, ro /caAou/ierov <h6v. rauro 

he rovTO ion /cat to eV rols i\ivoL£. irrcl tolvvv 

10 iuTL O(f)aLp0€Lhr]9 6 ixLi'o^y /cat ovx a)07T€p eVt tojv 

dXXojv oorpecxjv rod GojpLaros kvkXos els, 6 S* e)(luos 

ov rfj ptev TOiovTos rfj 8' ov, dXXa Travrrj opiOLos 

{G(f)aLpo€iSr]g ydp), dvayKi) /cat to wov opLOLOJS exetv 

ov yap ioTLVy (Lorrep rots aAAot?, to kvkXco dv- 

opuoLOV iv pL€Gcp ydp Tj Ke(f)aXrj Trdaiv avTols, to) S' 


OLOV T etvai to ojov — ovhe ydp rot? aAAot? — dAA' errl 
OaTepa tov kvkXov piovov. dvdyKT] tolvvv, irrel 
TOVTO pL6V aTravTCUv KOLvoVy lSlov 8' e/cetVou etrat 
TO CTCO/xa a^atpoetSes", pLr) elvai dpTia Ta cod. /caTa 
SidpieTpov ydp dv tjv, Std to opLotojg 8etv ex^iv to 
20 €v6ev /cat evOev, et tjv dpTia [/cat /caTo, hidpLeTpov^' 
ovTCOS 8' e;(dvTa)V eV dpL(f)6T€pa dv tov kvkXov 

ctxOV TO (hov. TOVTO 8' OVK TjV OvS* €7x1 TCJJV dXXoJV 

ooTpecxJV i-TTi BdTepa ydp ttjs nepLcfyepeLas exovoL Ta 
OGTpea /cat ot KTives to tolovtov pLopiov. dvdyKT) 
Toivvv Tpta 7] 7T€.VT€ elvai r^ d'AAoy Tti^' dptdpLov 
25 TTepLTTOv. el pL€V ovv Tpta etx^, TToppoj Xiav (jdvY 
TjV, et 8e TrXeLOJ tcjv vreWe, Gwex^s dv tovtcdv Sc 
TO pi€v ov ^IXtlov, to 8* OVK eV8e;^d/xevov. dvdyKT) 
dpa ttcVt' avTOvs ^X^^^ "^^ ^^• 

Atd Tr]v avTTjv 8' atTtav /cat tj KoiXia TOLavTTj 
€0"p(taTat Kat to tcov oSovtojv togovtov eGTL ttXtjOos. 
€KaaTOV ydp tojv cocov, olov aco/xct Tt tov t,a)ov ov, 


^ secludenda. ^ (ai^) Ogle. 

^ KoiXias Ogle : {co^s vulg. 



on one side of the body only ; it is the same as that of 
the Sea-urchin. Now the Sea-urchin is spherical, 
and is not just one flat disk hke the Oysters ; thus, 
being spherical, it is not different shapes in different 
directions, but equiform in all directions ; hence of 
necessity its " ovum " is correspondingly arranged, 
since this creature's perimeter is not, as in the others, 
non-equiform ° : they all have their head in the 
centre, whereas the Sea-urchin's is at the top. 
Yet even so the " ovum " cannot be continuous, 
since no other of the Testacea has it thus ; it 
is always on one side of the disk only. Hence, 
since this is a common property of all species 
of Testacea, and the Sea-urchin is peculiar in having 
a spherical shape, the result follows of necessity that 
the Sea-urchins cannot have an even number of ova. 
If they were even, they would have to be arranged in 
diametrically opposite positions, because both sides 
would have to be alike, and then there would be ova 
on both sides of the circumference ; but this arrange- 
ment is not found in any of the other Ostreae ; both 
Oysters and Scallops have ova on one side only of 
their circumference. Therefore there must be three, 
or five, or some other odd number of ova in the Sea- 
urchin. If there were three, they would be too far 
apart ; if more than five, they would be quite con- 
tinuous ; the former would not subserve a good 
purpose, the latter is impossible. Therefore the 
Sea-urchin must of necessity have five ova. 

For the same cause the creature's stomach is cloven 
into five and it has five teeth. Each of the ova, being, 
as it were, a body belonging to the creature, must 
conform to the general character of the stomach, 

• That is, it is circular in all planes, not in one only. 

' 331 


680 b 

dvayKalov ivrevOev yap r) av^r]ais. jjLid? ^leu yap 
ovarjg tj TToppw dv rjGav, rj ttolv dv Karelx^ '^o kvtos, 
cocrre /cat Svoklvtjtov etvai rov i)(ivov Kal [xtj ttXtj- 
povadai rrjs Tpo(l)rjs to dyyelov rrevre 8* ovtcjjv 
rcjv StaAet/xjLtarcov dvayKT] irpos eKaGTCp ovaav 
85 7T€VTa)(fj SLfiprjadai. Sea rrjv avrrjv S' alriav Koi 
TO T(x)v ohovrcxjv €orL TOGovrov ttXtjOo?^' to yap 
681 a ofJLOLOv ovTco? dv 7) <f)VGLS ^trj aTroSeSojKvta tols 
elprjixevoLS [xoplois. 

Atdrt /xev ovv Trepirrd Kal rooavra tov dpidpLov 
ex^i 6 exlvo£ rd cod, etpr^raf Stort S' ol /xey TrdpLirav 
pLLKpd ol Se /xeyaAa, atrtov to OepfioTepov? elvat 
rrjv (fiVGiv TOVTov?' 7T€TT€iv ydp TO deppiov SvvaTaL 
5 Tr]V Tpo(f)r]v pidXXoVy hioTrep TTepirTaypLaros TrX-qpeis 
ol dppajTOL pidXXov. Kal TrapaGKevd^eL klvtjtlkco- 

repOV? Tj TTJS (f)VG€aJS OeppLOTTjS, COCTTC V€pL£Gdai Kal 
pLTj pL€V€LV iSpaLOVS. GTjfXeloV §€ TOVTOV TO ^X^LV 

Tovs TOLOVTOV9 del Tt irrl tcov dKavdwv ujs klvov- 
pL€vov5 TTVKvd' xpdJvTat ydp ttogI Tat? dKdvOaig. 
10 To, 8e rrjOva puKpov tcov (f)VTd}V Sta^epet ttjv 


ydp TrdfJLTTav exovGL cfivrov SvvajjLiv. r] ydp <j)VGis 
pLeTa^alvei Gvv^xdos diro tcov diljvx(J^v els to, ^a>a 
8ta TCOV t,(I)VTCov pLev ovk ovtcjjv be ^cpcov, ovtcos 
coGre hoKelv TrdjJLTrav fiiKpov hiacfyepeiv darepov 
15 darepov rep Gvveyyv? aAAi^Aots". o piev ovv GTToyyos, 

^ hinc manus recentior E ( =E). 

" This is true ; but motion is effected mainly by the tube- 
feet, not noticed by Aristotle {vide Ogle). 
* The " sea-squirts." 



because growth has its origin from the stomach. 
Now if there were only one stomach, either the ova 
would be too far away from it, or the stomach would 
entirely fill up the cavity, which would make it 
difficult for the Sea-urchin to move about and to find 
sufficient food to replenish itself. But, as it is, there 
are five ova separated by five intervals, and so there 
must be five departments of the stomach, one for 
each interval. For the same reason there are five 
teeth, since this enables Nature to assign one tooth 
alike to each ovum and each department of the 

I have now stated why the Sea-urchin has an odd 
number of ova, and why it has five of them. Now 
some Sea-urchins have quite small ones, and some 
large : the reason for this is that the latter have a 
hotter constitution, and the heat enables them to 
concoct their food better. This explains why the 
uneatable ones tend to be full of residue. This 
natural heat also induces the creatures to move about, 
and so instead of remaining settled in one place they 
keep on the move as they feed. An indication of 
this is that Sea-urchins of this sort always have some- 
thing sticking on to their spines (which they use 
as feet),** which suggests that they are continually 
moving about. 

The Ascidians ^ differ very little in their nature from 
plants, but they are more akin to animals than the 
Sponges are, which are completely plants. Nature 
passes in a continuous gradation from lifeless things 
to animals, and on the way there are living things 
which are not actually animals, with theresult that one 
class is so close to the next that the difference seems 
infinitesimal. Now a sponge, as I said just now, is in 

' 3S3 


681 a 

ojGTTep eiprjTaiy /cat tco t,rjv 7TpoG7Te(f)VK(l)S fJLOvov, 

OLTToXvOels Se fJLT] i,TJV, OfjLOLOJS ^X^^ TOt? <j)VToZs 

TT-avreAcDs" ra 8e KaXovfieva oXodovpia koi ol irvev- 
jjLoves, €TL Se /cat erepa Toiavr iv rfj daXdrrr) 
fiLKpov Sia(f)€p€L rovTcov rep aTToXeXvadat' ata^Tjcrtv 

20 pi€v yap ovSepLLav €;^et, l^fj S' ojOTrep ovra (j>VTa 
aTToXeXvpLeva. eori 8e /cat iv rols imyeiois <j>vroZs 
€VLa roLavra, a /cat l,fj /cat yiverai ra pLev iv eripois 
(j)vrols, ra he /cat aTToXeXvpieva, olov /cat to e/c rod 
YiapvaGGov KaXovpLevov vtto rivcxjv iTriTrerpov rovro 
yap l,fj TToXvv ;)^povop' Kpejidpievov dva> eTrt rcov 

25 TrarrdXojv. eon S* ore /cat ra rr]dva, /cat et rt 
roiovrov erepov yevos, ra> piev TrpooTrecfyvKos ^rjv 
pLOvov (j)vr(x) iraparrX-qGLOv, rep 8' *ix^^^ '^^ GapKcoSes 
So^eiev dv ex^LV riv* alGdiqGiv' dBr]Xov Se rovro 
TTorepojs dereov. 

"^X^^ ^^ '^ovro ro ^cvov Svo TTopovs Kal pilav 

80 hiaipeGLV, fj re hex^rai rrjv vyporrjra rrjv els 
rpo(f)'qv, /cat fj TrdXiv SiaTrepLTreL rrjv VTToXeLTTopLevxjv 
LKpidSa' TTepirrcjopLa yap ovSev ion hr^Xov exov, 
ojGTTep rdXXa rd oGrpaKoSeppLa. 8to pidXiGra /cat 
rovro, Kav et rt aAAo roiovrov rcov i,(pajv, (jyvriKov 
hiKaiov KaXelv ovhe yap ra>v (jivrcov ovhev €X€L 

85 TTepirrojpia. 8ta pieGov he Xeirrov hidt,<jjpLa, iv a> 

TO Kvpiov vTrdpx^iv evXoyov rrj? ^corjs. a? he 

KaXovGLV OL pLev Kvlhas ol 8' dKaX'iq<^as , eGri piev ovk 

681 b oGrpaKoheppLa, dAA' e^co TTiTrrei rwv hirjprjpLevwv 

yeva)v, iTrapL^orepit^eL he rovro /cat (f)vrcp Kal ^cpco 

" Or " sea-cucumbers." 

" The precise reference of this term is not known. 
* Sea-anemones, called by the Greeks " sea-nettles." 


all respects like a plant : it lives only while it is 
growing on to something, and when it is pulled off it 
dies. What are called Holothuria and the Sea-lungs^ 
and other similar sea-animals differ only slightly 
from the sponges in being unattached. They have 
no power of sensation, but they live just as if they 
were plants unattached to the soil. Even among 
land-plants such instances exist : living and gro^\ing 
either on other plants or quite unattached : for 
example, the plant found on Parnassus, sometimes 
called the Epipetron (Rockplant). If you hang this 
up on the pegs ^ it will keep alive for a consider- 
able time. Sometimes it is doubtful whether these 
Ascidians and any other such group of creatures 
ought to be classed as plants or as animals : In so far 
as they live only by growing on to some other object 
they approach the status of a plant ; but yet they 
have some fleshy substance and therefore probably 
are capable of sensation of a kind. 

• This particular creature (the Ascidian) has two 
orifices and one septum ; by one orifice it takes in fluid 
matter for food, by the other it discharges the surplus 
moisture ; so far as can be seen it has no residue like 
the other Testacea. And as no plant ever has any 
residue this is a strong justification for classing it 
(and any other such animal) as a plant. Through its 
middle there runs a thin partition, and it is reason- 
able to suppose that the governing and vital part of 
the creature is situated here. As for what are called 
Knides or Acalephae,^ they are not Testacea, it is 
true, but fall outside the defined groups. In their 
nature they incline towards the plants on one side 

Those common to the Mediterranean are more virulent in 
their stinging powers than those of the north. 

, 335 


681 b ^ ^ 

TTjv (f)UGLV. Toj (jLev yap OLTToXvecrOaL Kal rrpoo- 

TTLTTTeiv TTpos rTjv Tpo(f)rjv eVta? avTOJV ^a>t/cov ccrrt, 
6 Kal ra> aladdveoOai rcov TTpouTrnnovTayv' en he rfj 
rod GcofJLaros rpaxvrr]TL ;)^prJTat TT-pos" rrjv acjTiqplav' 
Tip 8' areXes elvai Kal TTpoGcfyvead at rap^ecus" rat? 
TTerpaig ro) yevei rcov cfyvTcbv TrapaTrX-qGLOv, Kal rw 
TTepiTTCopLa pLTjSev exeiv ^avepov, GTOfJca S' ex^i-v. 
ofMOLOv Se rovTcp Kal ro tujv aGrepojv IgtI yevos — 

10 Kal yap rouro ttpqgttltttov eKxyj-ill^eL ttoXXol tojv 
oGrpecov — rots' t' a7ToXeXvp.evois rcov elprjfjLevojv 
^cpcov, OLOv TOLS TC piaXaKLOLg Kal Tot? [xaXaKO- 
GrpaKOLs. 6 S' avros Xoyos Kal rrepl rcov oGrpaKo- 

To. fxev ovv pLopia ra Trepl ttjv rpocjy'qVy airep 
avayKaZov TraGiv VTrapxeiv, exei rov TrpoeipiqpLevov 

15 rpoTTOV, Set 8e St^Xovotl Kal rcov rols evaipiois 
VTTapxovrcov Kara ro Kvpiov rcov aiGOrjGecov exeiv 
dvdXoyov ri pLopiov rovro yap Set TraGiv vnapxeiv 
rols ^ojot?. eart Se rovro roZs p.ev pLaXaKioig ev 
Vfievi Keifxevov vypov, St' ovnep 6 Grofxaxos rerarai 
TTpo? rrjv KoiXiaVy irpoGTre^VKe Se jrpos ra rrpavrj 

20 fjLoiXXov, Kal KaXeZrai pLvns vtto rivcov. roiovrov S* 
erepov Kal roZs (xaXaKOGrpaKOLs eGri, Kal KaXeZrai 
KOLKeZvo fJLvrLg. eGri S' vypov Kal GCOfiarcbSe? dpua 
rovro ro jJLopiov, reivei Se St' avrov, KaOajrep 
elp-qr ai, Sta fxeGOV fxev 6 Grofxaxos' el yap tjv 
/JLera^v rovrov Kal rod Trpavovs, ovk dv rjSvvaro 

2r, XafjL^dveiv opLOLCog StacrraCTtv elGLOVGr]g rrjs rpocfj-fj? 
Sta rr]v rod vcorov GKXrjporrjra. eVt Se rijg fivrf,8os 
ro evrepov e^coOev, Kal 6 60X65 Trpos rep evrepcp, 

<* That is, dorsal. 


and the animals on the other. Towards the animals, 
because some of them detach themselves and fasten 
upon their food, and are sensible of objects that come 
up against them ; and also because they make use 
of the roughness of their body for self-preservation. 
Towards the plants, because they are incomplete, 
and quickly attach themselves to rocks ; and further, 
because they have no residue that can be seen, 
though they have a mouth. The group of Starfish 
resembles these creatures ; Starfish too fasten on to 
their food, and by doing this to oysters suck large 
numbers of them dry. But Starfish also resemble 
those unattached creatures of which we spoke, the 
Cephalopods and the Crustacea. The same may be 
said of the Testacea. 

The parts connected with nutrition are such as I 
have now described. These must of necessity be 
present in all animals. But there is yet another part 
which every animal must have. These creatures must 
have some part which is analogous to the parts 
which in blooded animals are connected with the 
control of sensation. In the Cephalopods this con- 
sists of a fluid contained in a membrane, through 
which the gullet extends towards the stomach. It is 
attached to the body rather towards the upper " side. 
Some call it the mytis. An organ just like this, also 
called the mytis, is present in the Crustacea. This 
part is fluid and corporeal at the same time. The 
gullet, as I said, extends through the middle of it. 
If the gullet had been placed between the mytis and 
the dorsal side, the gullet would not have been able 
to distend sufficiently when the food enters, owing to 
the hardness of the back. The intestine is placed up 
against the outer surface of the mytis, and the ink-bag 

, 337 


681 b ^ 

O77C0S" on TrAetCTTOV aTTexj] rrjs elaoSov Kal to 

SvGx^p^S CLTToOev fj rod ^eXriovos /cat rr\s dpx^S' 

on 8' 6(jtI to dvdXoyov rfj Kaphia rovro ro [jLopiov, 

80 SryAot o roTTOS [ovro^ yap eanv 6 avros) koL rj 

yXvKVTTjg TTjS VypOTTjTOS d)S OVUa 7T€Tr€[XfX€Vrj Kol 


Ev Se Tols 6orpaKohepp,oig e;\;£t pikv rov avrov 
TOTTOV^ TO KVpLov TTjS aLGQ-qdeco? , tJttov S' i7TLhr]Xov. 
TrXrjv Set t,7]T€lv del Trepl jLtccrdrT^Ta TavT7]v Tr]v 
apx'Tjv, ooa puev piovifiay tov Sexop-evov pLoptov tt^v 

85 TpO(f)T]V, Kal St* OV TTOieiTai TTjV dlTOKpLGiV 7] 
T7]V GTreppaTLKTjV 7) TTjV TT€pLTTCOpaTLKT^V , OGa §€ 

682 a Kai TTopevTiKCL Tojv t,(x)ajv, del ev^ ro) pLeGco tojv 

SeftcDv /cat rcDv dpiGTepcbv . 

Tots' S* ivTopLoig TO pi€V TTJs ToiavTTis dpx^s 
piopioVy a)G7rep iv rots" TrpcoTOLs eXexQ'"] Xoyois, 
jLtera^u K€(f)aX7J? Kal tov Trepl ri^v KoiXiav egtI 


5 Se TrAetco, Kaddirep rot? tovAcoSeot /cat /u-a/cpot?" 
Sionep hiaTepivopeva t,r). ^ovXeTau piev yap rj (j)VGis 


pL€V TTOiei pLovov ev, OV SwapLeinj Se TrXeioj.^ hrjXov 
8* ev eTepois erepcoy jLtaAAov. 

To, 8e TTpos rrjv Tpo(f>r]v pLopua ov ttolglv opLolcJS, 

10 aAAa hia(j)opdv e;)^et ttoAAt^p'. ivTos yap tov gto- 

pLaTos eVtot? pL€V €GTL TO KaXovpLevov KevTpov, 

WGTTepavel GvvdeTOV Kal ^xov yXcoTTrjg Kal ^etXcuv 

^ roTTOv Pkackham : rponov viilp:. ^ ev V : om. vulg. 

^ sic SL Y (Suva/u.ei'a bis S) : Kal hvvafjLevrjv fiev, €i> ttolcl ixovov 
OV bvvafievT) Se ttXcloj Z : ov bwa/xeirrj S' evepyeia noiel fiovov €v, 
bvvdfxeL 8e ttXclw vulg. (cf. 667 b 25). 



up against the intestine ; this is to ensure that it and 
its unpleasantness are kept as far as possible from the 
body's entrance and from the sovereign and most 
noble part. The mytis occupies a place which corre- 
sponds exactly with that of the heart in blooded 
creatures : which shows that it is the counterpart of 
it.** Another proof of this is that the fluid in it is 
sweet — that is, it has undergone concoction and is of 
the nature of blood. 

In the Testacea the part which rules sensation 
occupies the same place but is not so easy to pick out. 
But this source of control should always be looked for 
around some middle position in these creatures : in 
stationary ones, in the midst between the part which 
receives the food and the part where the seed or the 
residue is emitted ; and in those which move about, 
always midway between the right side and the left. 

In insects the part where this control is placed, as 
was said in the first treatise,^ is situated between the 
head and the cavity where the stomach is. In the 
majority there is one such part, but in creatures like 
the Centipede, that is, which are long in the body, 
there are more than one : so if the creatures are cut 
up they go on living. Now Nature's desire is to make 
this part a unity in all creatures, and when she can, 
she makes it a unity, when she cannot, a pluraUty." 
This is clearer in some cases than in others. 

The parts connected vdih nutrition are by no means 
alike in all insects ; indeed they exhibit great 
differences. For instance : Some have what is 
known as a sting inside the mouth — a sort of com- 
bination of tongue and lips, — which possesses the 

* The heart of invertebrates escaped the notice of Aristotle. 
* At Ilist. An. 531 b 34. « Cf. 667 b 22 if. 

■ 339 


682 a 

a/xa SvvaixLV rols 8e (jlt^ exovuiv efXTrpooOev to 
Kevrpov iorlv ivros rcov oSovrcov tolovtov alaOrj- 
rrjpLOv. TOVTOV 8' ixofi^vov Trduiv evrepov evdv /cat 

16 aTrXovv IJ-^XP^ '^V^ i^oSov rod TTepLTTcvfiaTOS' evioLS 
8e rovTo iXlKrjv ex^t. ra Se KoiXiav /xera to GTOfia, 
OLTTO Se rrjs KOiXias to evTepov elXiyfjLevop, ottoj^ 
ocra ^pcoTLKcoTcpa /cat fxel^oj tt^v cf)VGLv vnohox^v 
kxxi TrXeiovos Tpocl}rjs. to Se tcov TeTTiycDV yivos 
IS lav €X€i {JLaXiGTa tovtcov (J^vglv to yap avTO 

20 fxoptov ep^et OTOjjLa /cat yXojTTav ovfXTrecfiVKos, St* 
ov KadaTrepel Slol pit,'r]S Sep^erat ttjv Tpo(f)r]u diro 
TCOV vypojv. rrdvTa fxkv ovv IgtIv oXiyoTpocjya to, 
evTopia Tojv ^ojcov, ovx ovtco Slol fXLKp6Tr]Ta cos 
Sid ipvxpoTr)Ta {to yap Oepixov /cat Setrat Tpocf)rjs 
/cat Tr€TT€t TTjv TpocjiT^v Tax^oJS , TO Sk ijjvxpov d- 

25 Tpo(f>ov), jLtaAtcrra 8e to tcov TeTTiycov yevos' LKavrj 
yap Tpo(f)r] tco ocopiaTi rj e/c tov irvevixaTog vtto- 
jxevovaa vypoTiqs, KaOdirep TOt? icjirjfxepoLs ^cools 
(ytvcTat Se TavTa irepl tov noi^TOv), ttAt^v e/cetva 
/xev t,fj pads r^p.epas ;\;poj-'ov, TavTa Se TrXecovcov 
pi€V r]p.€p(jjv, oXiycov Se tovtcov. 

30 'ETTet 8e TTepl tcov ivTos VTrapxdvTCov pLoplcov tols 
t,cx)OLS etprjTai, ndXiv nepl tcov Xolttcov tcov gktos 
liraviTeov. dpKTeov 8' avro tcov vvv €Lprjf.L6vcoVf 
dAA' ovK d(/>' Sv dTTeXiTTOjjLeVy ottcos dno tovtcov 
SLaTpL^rjv iXdTTCO ixovTCOv eirl tcov TeXeicov /cat 
ivaipicov ^cocov 6 Xoyos GxoXdl,r] fxdXXov. 

35 VI. Td jLtev ovv evTOfia tcov t^cocov ov TToXvp-eprj 
pkv TOV dpiOpiov ioTLv, djjicos 8' e;(et irpos d'AAT^Aa 
3 to 


character of both. Those that have no sting in front 
have a sense-organ of that sort behind the teeth. 
After the mouth, in all insects comes the intestine, 
which is straight and simple right up to the residual 
vent. (Sometimes, however, it has a spiral in it.) 
And some there are which have the stomach next 
after the mouth, while from the stomach runs a 
twisted intestine ; this gives the bigger and more 
gluttonous insects room for a larger amount of food. 
Of all these creatures the grasshoppers are the most 
peculiar. In them the mouth and tongue are united 
so as to make one single part, and through this they 
draw up their nourishment from fluid substances as 
through a root. All insects take but little nourish- 
ment ; and this is not so much because they are 
small as because they are cold. (Heat needs nourish- 
ment and quickly concocts it ; cold needs none.) 
This is most marked in the grasshoppers. They find 
sufficient nourishment in the moisture which the air 
deposits ; so do the one-day creatures which occur 
around the Black Sea. Still, they live only for the 
space of a day ; whereas the grasshoppers live for 
several, though not many, days. 

Now that we have spoken of the internal parts of 
animals, w^e must go back and deal with the remainder 
of the external parts. We had better begin with the 
creatures of which w^e have just been speaking, and 
not go back to the point where we left the external 
parts. This will mean that we take first those which 
need less discussion, and that will give more time for 
speaking of the " perfect " animals, i.e. the blooded 

VI. Insects first, then. Though their parts are not external 
numerous, insects differ from one another. They all 

' 3U 





682 a 

8ta</>opas'. 77oAi;77oSa fiev yap eoTL Trdvra Sea to 
682 b TTpog rrfv ^paSvTTJra Kal KaTai/jv^LV rrj? (f)VGeaJs ttjv 
TToXvTTohlav avvriKcorepav avrols ttouIv rriv Kivqaiv 
Kal jxaXiaTa TToXviroha ra pLaXiara Kareijjvyixeva Sta 
TO [JirJKOs olov TO Twv lovXcxJv yevos . €tl 8e 8td to 
6 dpxas ^x^LV TrXeiova^ at t ivTOfJLai etVt Kal ttoXv- 
TToSa /caTct TavTo} ioTLV. 

"Oaa 8* iXoLTTOvas e;^€t 77o8as", tttt^vcl TavT* ioTl 
npos TTjv eXXenpLV ttjv tG)v ttoSojv. avTcov 8e tcDv 

TTTTjVOJV (hv jJiiv ioTLV 6 ^LOS VOfiaSlKOS Kol SlOL TTjV 

Tpo(f)7]v dvayKalov eKTOTril^eiv, TeTpaTTTepd t€ ioTi 
Kal Tov Tov ucLpiaTos €^€1 Kov<f)ov oyKov, olov at Te 

10 /xeAtTTat Kal Ta GV(jL(f)vXa (,cpa TavTais' hvo yap e^' 
€KdT€pa TTTepd^ exovoLv. ooa 8e puKpd tG)V tolov- 
Ta)Vy hiTTTepa, Kaddirep to tojv fivicov yevos. Ta 8e 
^apea^ Kal TOt? ^tois iSpala TroXvTTTcpa jjiev o/xotco? 
Tat? /xeAtTTai?* ioTLv, ex^L 8' eXvTpa TOt? TTTepols, 

15 otov at T€ fJLTjXoXovdai Kal Ta ToiavTa tcov ivTOficov, 
07T0JS 0(x>t,rj TTjV TWV TTTepojv SuvafiLV ihpaicov yap 
ovTOJv evSidcfiOopa fidXXov ioTi tojv evKivrjTOjv, 
SioTTep €X€L (fypaypLOV Trpo avTOJV. Kal daxt-c^TOV Se 
TOVTOJV ioTL TO 7TT€p6v Kal aKavXov ov ydp iuTi 
7TT€p6v dXX V/JLTjV SepfxaTLKos, OS Sid ^rjpoTTjTa ef 

20 dvdyKTjg d^ioTaTai tov CTco/xaTo? avTOJV ipuxofievov 
TOV oapKcoSovg. 

"EvTOfia 8' eoTt 8ta Te Ta? elp-qjievas atVta?, /cat 
OTTOJS u<x)tpr]TaL hi dirdd €iav ovyKafirrTOfxeva' avv- 
cAtTTeTttt ydp Ta fxrJKos exovT avTCJV, tovto 8' ovk 
dv iyiveT avTols fXTj ovglv ivTOfJLOis. to, 8e firj 

^ ravrd Peck : Tavra Y : ravT vulg. : ravras Ogle. 
^ 7TT€pa TOV acvfxaTos vulg. : tov a. delevi. 
• ^apda Ogle : ^paxda vulg. * /xeAtTrats {ovk) Piatt. 



have numerous feet ; this is in order to make their (a) insects, 
motion quicker, and to counteract their natural slow- 
ness and coldness. Those which are most subject to 
coldness owing to their length (e.g. the Centipedes) 
have the greatest number of feet. Furthermore, 
these creatures have several sources of control ; and 
on that account they have the " insections " in their 
bodies, and the numerous feet which are placed in 
precise correspondence. 

Those that have fewer feet are winged by way of 
compensation. Some of these flying insects live a 
wandering life and have to go abroad in search of 
food ; so they have a light body and four wings, two 
on either side ; such are the bees and the kindred 
tribes. The small ones have only two \\'ings all told 
— like the flies. Those that are heavy and sedentary 
in their habits have the larger number of wings like 
the bees, but they have shards round their wings 
(e.g. the Melolonthae'^ and similar insects) to preserve 
them in their proper condition ; for, as these creatures 
are sedentary, their wings are more liable to be 
destroyed than those of the nimbler insects ; and 
that is why there is this protection round them. 
An insect's wing is not divided, and it has no shaft. 
In fact, it is not a wing at all, but a membrane of skin, 
which being dry detaches itself of necessity from the 
creature's body as the fleshy part cools off. 

I have already stated some reasons why these 
creatures have " insected " bodies : there is another, 
viz. it is so that they may curl up and thus escape 
injury and remain safe. It is the long ones that roll 
themselves up, and this would be impossible for them 
if they were not insected. Those that do not roll up 

* Perhaps cockchafers (Ogle). 



682b ^ ^ ^ ^ 

IXiKTo. avrcjv (jKXrjpvverai fjidXXov avviovra els ras 

25 rofxas. hr]Xov 8e rovro yiverai diyyavovTCov, olov 
eVt Tcov KaXovf-Uvcov Kavddpcjv (f)0^rjdevTa yap 
dKLvr]TL^€L, Kal TO CTOJ/xa yiverai GKXiqpov avTcov. 
dvayKOiov 8' evropLOis avrols elvai' rovro yap iv 
rfj ovaia avrcjv vrrapx^L ro TToXXdg e)(€iv dpxdg, Kal 

80 ravrrj TTpoaioiKe rols (j>vroZs. cooTrep yap rd (f)vrd, 
Kal ravra Statpou/xeva Svyarai ^rjv, ttXtjv ravra [lev 
yi'iXP'' "^^^oSt €K€Lva Se Kal reXeia yiverai ttjv (f)VOLV 
Kal Svo e^ evos Kal TrXeto) rov dpLdfjLov. 

"E;\;et S' eVta rojv ivrofiojv Kal Kevrpa Trpds 
^orjdeiav rcov ^XaTrrovrojv . to /xev ovv Kevrpov 

85 rols jLtev epLTTpoodev ion rols S* OTTiaOev, rols fxev 
epLTTpoodev Kara rrjv yXcorrav, rots S* ornodev Kara 
rd ovpalov. WGirep yap rols iXl^aoi rd rcjv 
d(T[X(jL)V alaOrjrrjpiov yeyevrjrai ;^p7^crt^ov rrpds re 
683 a rrjv dXKTjv Kal rr)V r7]s rpo(f)rjs xp-rjcrtv, ovrojs rdjv 
ivrdjJLOJV ivLOis rd /caret rr]v yXcJorrav rerayfievov 
aloddvovrai re ydp rovrco rrjs rpo(f)rjs Kal dvaXafi- 
PdvovGL Kal TTpoodyovrai avrrjv. doa he fi-q ianv 
avrcbv efXTTpooOoKevrpa, dhdvras €;^et rd piev 
6 ehcjohris X^P^^ "^^ ^^ '^^^ Xap^^dveiv Kal irpoodyeadai 
rrjv rpo(f)'qv, otov ol re [xvpijLrjKes Kal rd rdov pieXur- 
Tcov TTaacjv yevos- dua 8' oTnaddKevrpd eon, hid 
rd dvpidv ex^^v ottXov ex^^ rd Kevrpov. exovat he 
rd pLev ev eavrdls rd Kevrpa, Kaddnep at pbiXirrai 
Kal ol G(f)rJKes, hid rd TTrrjvd elvai- Xejrrd piev ydp 

10 dvra Kal e^co evcf)dapra (av)^ r]V el he nax^a rjv^ 
ajGTTep rols OKopTTtois, (^dpos dv Trapelx^v. rols he 

^ (av) Ogle. * 8e nax^a ^v Piatt : 8' direixev vulg. 



increase their hardness by closing up the insections. 
This is obvious if you touch them — e.g. the insects 
called Canthari (dung-beetles) are frightened when 
touched and become motionless, and their bodies 
become hard. But also it is necessarif for them to 
be insected, for it is of their essential being to have 
numerous sources of control ; and herein they re- 
semble plants. Plants can live when they are cut 
up ; so can insects. There is a difference, however, 
for whereas the period of survival of a divided insect 
is limited, a plant can attain the perfection of its 
nature when divided, and so two plants or more come 
out of one. 

Some of the insects have a sting as well, for defence 
against attackers. In some the sting is in front, by 
the tongue ; in others it is behind at the tail-end. 
Consider the elephant's trunk : this is its organ of 
smell ; but the elephant uses it as a means of exert- 
ing force as well as for the purposes of nutrition. 
Compare with this the sting of insects : when, as in 
some of them, it is ranged alongside the tongue, not 
only do they get their sensation of the food by means 
of it, but they also pick up the food with it and convey 
it to the mouth. Those which have no sting in front 
have teeth ; which some of them use for eating, 
others for picking up the food and conveying it to the 
mouth, as do the ants and the whole tribe of bees. 
Those that have a sting at the back are fierce crea- 
tures and the sting serves them as a weapon. Some- 
times the sting is well inside the body, as in bees and 
wasps. This is because they are winged, and a deli- 
cate sting on the outside of the body would be easily 
destroyed ; on the other hand, a thick one such as 
scorpions have would weigh them down. Scorpions 

, 345 


3 a 

OKopTTLOL? TTel^oZs ovui Kol KepKOv^ exovcTLV Givay- 
KOiov em ravTTj^ ^X^^^ '^^ Kevrpov, r^ firjdev ■)(p-qoLpiov 

€LVaL 77/30? TT^V OlXktJv . SiTTTepOV S' OvdeV ioTLV 

OTTiodoKevrpov Sta to audevrj yap Kal puKpa clvai 
15 SiTTTepd iuTLv iKava yap ra puKpa a'ipeodai vtto 
tCov eXarrovcov top dpLdfjLov. 8ta ravro Se rovro 
Kai epLTrpooOev e;^et to Kevrpov audevrj yap ovra 
pLoXis hvvarai rolg omadev^ rvTrreiv. rd Se 
TTOAVTTrepa, Sia ro jLtct^co rrjv (f)VOLv elvai, irXeiovcov 

r€TV)(y]K€ TTTepOJV Kal LG)(VeL TOtS" OTTiodev fJLOploLS. 

20 ^eXnov S' ivSexofievov firj ravro opyavov eirl 
avojjiOias ^x^iv xPV^^'^^y diXXd ro fxev dfivvrLKov 
o^vrarov, ro Se yXatrrcKov oop.(f)6v /cat OTraoriKov 
Trjs rpo(f)r}g. ottov yap evhex^^ai XPV^^^'' Svolv 
inl 8u' epya Kal purj epi7Tohit,€LV rrpos erepov, 
ovSev 7) (f)vuL<: e'tcode TTOielv wajrep r) ;)(aA/<:euTtACT7 

25 77/309 evreXeiav o^eXiGKoXvxvi-ov' dXX ottov (jltj 
ivSex^rai, Karaxprjrai rw avrco iirl TrXeioj epya. 

Tovs Se TToSas rovs rrpoodiovs /Ltet^ou? eVta rov- 
rojv ex^-iy OTTCos eTreihy] 8ta ro GKXrjp6(f)daXfxa etvau 
OVK aKpi^rj rrjv oipLV exovcri, rd rrpooTTLTTrovra rols 
rrpoodcoLs diroKadaipwoi OKeXeoiv drrep Kal (j^ai- 

80 vovrai -noiovGai at re /xutat Kal rd (JLeXirrcoSr] rcjv 
^wcDV del ydp xo-po-K^^ovcn rols TrpooBiois UKeXeuiv. 
rd S* dTTLoOia pLei^co rcov fieGCJV Sta re rr]v ^dhiGLV 
Kal rrpds to atpeodai paov and rrj? yrjg dvairer- 

* KcpKov Z (coniecerat Ogle) : Kevrpov vulg. 

^ TavTT] Ogle : TavT Vulg. 

^ omodev Ogle, Thurot : efx-rrpoadev vulg. 

" The principle of" division of labour " in a living organism, 
not stated again until 1827 (by Milne Edwards). See Ogle's 


themselves, being land-creatures and having a tail, 
are bound to have their sting on their tail ; otherwise 
it would be no use for exerting force. No two- 
winged insect has a sting at the rear ; these are small 
weak creatures, and can be supported by a smaller 
number of wings : that is why they have only two. 
The same reason explains why they have their sting 
in the front : owing to their weakness they cannot 
well deliver a blow with their hind parts. Many- 
winged creatures, on the other hand, owe their 
greater number of wings to their own greater size, 
and so too their hind parts are stronger and bear the 
sting. It is better, when it is possible, that one and the 
same organ should not be put to dissimilar uses ; that 
is, there should be an organ of defence which is very 
sharp, and another organ to act as a tongue, which 
should be spongy and able to draw up nourishment. 
And thus, whenever it is possible to employ two 
organs for two pieces of work without their getting in 
each other's way. Nature provides and employs two." 
Her habits are not those of the coppersmith who for 
cheapness' sake makes you a spit-and-lampstand 
combination. Still, where two are impossible, Nature 
employs the same organ to perform several pieces 
of work. 

Some insects, whose eyesight is not distinct owing 
to their eyes being made of some hard substance, have 
specially long forefeet, which enable them to clear 
away anything that comes down on to the eyes. 
Flies and bees and the like are obvious examples : 
they are always crossing their front legs. These 
creatures' hind legs are longer than their middle ones 
for two reasons : (1) to assist them in walking, and 
(2) to lift them more easily off the ground when they 

M , 3-i7 


683 a ^ 

ofMeva. oaa Se TT-qSi-jTiKa avrcov en [xaXkov rovro 

<f)av€p6v, olov at t' aKplSeg /cat to roJv ipvXXcov 
35 yivos' orav yap Kaixijjavr eKreLvrj ttolXlv, dvayKalov 
dno rrj? yrjg rjpQai. ovk ejXTrpoodev 8* aAA' 
683 b OTTtcr^ev fJLovov exovGL rd TT-qSaXLcohrj at a/cptSe?* 
rrjv yap KafJLirrjv dvayKalov etaoj KeKXdodai, rGiV 
8e TTpoaOiojv kcoXojv ovSev eon tolovtov. e^diroZa 
Se rd roiavra Trdvr iarl ovv rots dXTLKols j-Lopiois. 
VII. TcJov 8' ooTpaKohepixojv ovk ean to oajfia 
6 TToXvpiepe?. rovTOV 8' atrtov to fiovifiov avru)V 
elvai TTjv (f)Voiv TToXvixepearepa ydp dvayKalov 
€LvaL TOJV ^cpCDV rd KLvrjTLKd Old TO (TrXelovsy^ ctvai 
avTtov 7Tpd^€is' opydvojv ydp Selrai TrXeiovcov rd 
TrXeiovajv pLerexovTa KLvrjaecov. tovtojv he rd fiev 
aKLvqra Trd/jLTrav iarl, rd 8e p^iKpas fierex^i' Ki- 
lo VT]G€cos' dAA' 7] (J)V<JL5 TTpos GCjjrTjpiav avrols rrjV 
rujv oarpaKCOV OKXr]p6rr)ra TTepidOrjKev. eon 8e 
TO, ixev [JLOvoOvpa rd 8e btdvpa avrojv, rd he orpofJL- 
pcoSr], KadaTTep eLprjr at Trporepov /cat toutcuv TCt 
fi€V iXiKTjv e^ovra, olov K-qpvKe?, rd 8e a(j)aLpoeihr\ 
fjiovov, KadaTTep rd rcov ex^vcov yivos . /cat rwv 
15 hidvpojv rd fiev ianv dvanrvKra, olov Krives /cat 
pives (e77t ddrepa ydp ovyKeKXeiurai, wore av- 
oiyeaOai irrl ddrepa /cat (jvyKXeUadai), rd 8' iir 
dfJL(f)a) ovp,7Te(f)VK€V, olov rd rcov gojXtJvcjov yevos. 
diravra 8e rd oarpaKohepp^a, Kaddirep rd (f)vrd, 
20 Kara) rrjv K€(f)aXr]v 'e-)(^i. rovrov 8' atVtoy oTt 
Karajdev Xapi^dvei rrjv rpo(f)rjv, ajGirep rd (j>vrd 
rals pit,ais. Gvjx^aiveL ovv avrols rd p,kv Karoj 
dvco €X€iV, rd 8' dva> Karco. iv vpivi 8' eCTTt, hC 

1 (jtX^Lovs) Peck: {noWas) Piatt. 


rise in flight. This pecuHarity is even more notice- 
able in the leaping insects, such as locusts and the 
various sorts of fleas, which first bend their hind legs 
and then stretch them out again, and this forces them 
to rise up from the ground. The rudder-shaped legs 
which locusts have are at the rear only and not in 
front ; this is because the joint must bend inwards ,** 
and no front limb satisfies this condition. All 
these creatures have six feet, inclusive of the parts 
used for leaping. 

VII. In Testacea the body is not divided into (?>) Testacea. 
several parts, owing to their being of stationary 
habits, as opposed to creatures which move about : 
the latter are bound to have more parts to their body 
because their activities are more numerous, and the 
more motions of which a species is capable, the more 
organs it requires. Now some of the Testacea are 
altogether stationary : others move about but little ; 
and so, to keep them safe. Nature has compassed 
them about with hard shells. Some of them are (as I 
said earlier ^) one-valved, some two-valved ; and some 
conical, either spiral like the Whelks, or spherical 
like the Sea-urchins. The two-valved shells are 
divided into (a) those M'hich open — i.e. which have a 
joint on one side and can open and shut on the other ; 
e.g. the scallops and mussels ; (6) those which are 
joined together on both sides, e.g. the group of razor- 
fishes. In all Testacea, just as in plants, the head is 
down below. The reason for this is that they take up 
their food from below, as plants take it up by their 
roots ; so they have their nether parts above and their 
upper parts below. These creatures are enveloped 
in a membrane, and through this they strain fresh- 

« See note on 693 b 3, p. 433. » At 679 b 16. 


683 b ^ 

ov SirjOel TO TTOTLjj-ov /cat Xaix^dvei ttjv Tpo(f)-^v. 

ex^i' Se Ke(j)a\riv fxev Trdvra, rd 8e rod crdjjLtaro? 
ixopia TTapd to rrjg TpO(f)i]s Scktikov dvcovvpa 
rdXXa . 

25 VIII. To, he fiaXaKOGrpaKa Trdvra Kal TTopevTLKd, 
Sio TToScDV ex^t' ttXtjOos. €Gtl he yevr] jxev rerrapa 
rd /xeytCTT* aurcDv ol re KaXovpevoi Kdpa^oi /cat 
acrra/cot /cat Kapihes /cat /cap/ctVot* toutojv S' 
eKaarov TrXeioj e'lhf] earl hia(j>epovra ov fxovov Kara 

zo TTjv fJLop(f)r]v dXXd /cat /cara ro jxeyeOos ttoXv' rd 
fiev ydp [leydXa rd he puKpd TTdfjLrrav avrcov eoriv. 
rd fxev ovv KapKwcohrj /cat Kapaj^whr] rrapopLoi 
earl rw XV^^^ ^X^*-^ d[jL(f)6repa. ravras S' ov 
TTopeias exovGL x^P''^> dXXd rrpos rd XajieZv /cat 
Ko^raGX^Xv dvrl ;)(etpajv. Sto /cat KdpLTrrovGLv ivav- 

35 rtajs ravra? rols ttogLv rovs p-^v ydp errl rd koZXov 
rdg S' IttI rd Trepicfiepeg KapLnrovGL /cat eXiGGOVGiv 
ovroj ydp ;!^pr^CTt/ rrpds rd Xaf^ovoai 7TpoG(f)epeGdai 

684 a rrjv rpo(f)rjv. 

AtacjiepovGL S' fj ol pev /capa/3ot exovGLV ovpdv, 
ol he KapKLVoi ovk exovGiv ovpdv rots p^ev ydp hid 
rd vevGriKols elvai ;)^p7Jo-i^os' r^ ovpd [veovGt ydp 
diTepeihopevoL olov irXdrais avrals), rots he Kap- 

5 kLvols ovhev xPV^^I^ov hid rd irpoGyeiov etvai rdv 
^iov^ avrcnv Kal elvai rpcoyXohvras. ogol 8' avrojv 
TTeXdyioi etVt, 8ta rovro rroXv dpyorepovs exovGi 
rovs TTohas^ TTpds rrjv TTopelav, olov at re palai 
Kal ol 'Hpa/cAea>Tt/cot KaXovpevoi KapKivoi, on 
oXlyr) KLVTjGei ^^pcoyrat, dAA' rj acorrjpLa avroXs 

I'j Toj oGrpeiwheis elvai yiverai' hid at /zev p.alai 

^ TO /3iov Bekker per typothctae errorem, 
^ avTwv post TTohas vulg. : om. Y. 

PARTS OF ANIMALS, IV. vii.-viii. 

water to drink, which is their way of taking nourish- 
ment. All of them possess a head, but except for 
the part which takes in the food none of the other 
parts has a special name. 

VIII. All the Crustacea can walk on land as well as (c) Cru- 
swim ; and hence they all have numerous feet. There ^*^^" 
are four main groups of Crustacea, called (1) Carabi ; 
(2) Astaci; (3) Carides; and (4) Carcini." Each of 
these contains several species which differ not only 
in shape, but also in size, and that considerably, for 
some species are large, others extremely small. The 
Carcinoid and the Caraboid Crustacea resemble each 
other, in both having claws. These claws are not for 
the sake of locomotion, but serve instead of hands, 
for catching and holding ; and that is why they bend 
in an opposite direction to the feet, which bend and 
twist toward the concave side, while the claws bend 
toward the convex side. This makes the claws 
ser\iceable for catching hold of the food and convey- 
ing it to the mouth. 

The two groups, Carabi and Carcini, differ in that 
the former have a tail and the latter have not. The 
Carabi find a tail useful because they are swimmers : 
tliey propel themselves with it as though with oars. 
A tail would be useless to the Carcini, which spend 
their lives near the land and creep into holes and 
crannies. Those that live out at sea and move about 
but little, and owe their safety to their shelly exterior, 
have for these reasons feet which are considerably less 
effective for locomotion : examples of this are the 

<* Roughly, these four divisions may be represented by our 
own groups, thus : (1) lobsters ; (2) crajrfish ; (3) prawns and 
shrimps ; (4) crabs, 

- 351 


AeTrrocj/ceAetS', ol S' *H/3a/<:AeajTt/<:ot fiLKpoGKeXels 

01 he TrdfjLTrav yuKpol KapKLVoi, ot aXiaKovrai Iv 
ToXs fiLKpoLS lxOvSlol?, €xovgl tov? TeAeuTatou? 
TrAaret? TroSa?, tva rrpos ro velv avrols XP^^-tjUOt 
djGLV, ojGTrep 7TT€ pvy ta rj irXdras exovreg rous" TToSas. 

At he Kaplhes tcjv fxev KapKivoeihwv hia(f)epovoL 
15 ra> ex^iv KepKov, rchv he Kapa^oeihajv hid to (jltj 
ex^t^v p^TyAas" a? ovk exovau hid ro ttXelovs ^X^^^ 
rrohaSy ivravOa ydp tj eKeWev dvrjXa)Tai av^rjGL?. 
TrXelovs 8' exovui TTohag, on vevorLKcorepd eoriv 
t) TTopevTLKcorepa. 

To, 8' eV TOtS" V7TTLOIS pLOpia Kal TTepl T7]V Ke- 

(f)aXr]v rd fxev els to he^aaOai to vhcop Kal dcfielvau 
20 exovGL ^payxoeihrj- TrXaKOjheGTepa he to, KaTOj at 
d-qXeiai rcjv dppevauv Kapd^cxjv exovai, Kal to. eV 
TO) eVtTTTuy/xart hauvTepa at drjXeiaL KapKLVOL 
TOJV dppevojv, hid to eKTeiveiv to, (hd rrpos aura, 
aAAa piT] aTToOev, ojo-nep ol Ixdveg Kal rdAAa ra 
(^cpdy TLKTOVTa- evpvxoJpeoTepa ydp ovTa Kal pLel^co 
25 ;!(djpay e;)(et rots' cools pidXXov. ol [lev ovv Kapa^oi 
Kal ol KapKLVOL Trdvres Trjv he^Ldv exovcrL XV^W 
[xell^oj Kal LGX^poTepav toIs ydp he^Lols rravTa 
7T€(f)VKe TO, ^cpa hpdv /xaAAov, rj he (^vgls aTroStdw- 
GLV del ToZs XP^cr^ct' hwafievoLs eKaGTOV t) pLOVoos 
r] pdXXoVy OLOV x^uAtoSoyras- Kal ohovTas Kal 
80 KepaTa Kal TrXrJKTpa Kal TrdvTa ra rotaura p,opLa, 
OGa Trpos ^o-qdeLav Kal dA/<:rjv eGTLv.^ 

Ot 8* acrra/cot pLovoL, orroTepav dv TVxoJcrf'V 
exovGL p.eL^oj tcjv xV^djv, Kal at ^r^Aeiat /cat ot 

^ <a»a) Peck : r-qKOvra S : KvtoKOvra PY : woTOKOvvra Ogle. 
2 ^(jTif, Peck : eiaiv vulg. 



Maiae ^ (whose legs are thin) and the crabs called 
Heracleotic (whose legs are short). 

The little tiny crabs, which are found among the 
catch with small fishes, have their hindmost feet flat, 
like fins or oars, to make them useful for swimming. 

The Carides differ from the Carcinoids in having a 
tail, and from the Caraboids just mentioned in not 
having claws. Claws are absent because they have 
more feet : the material for their growth has gone 
into the feet. And they have more feet because they 
svn.m about more or move about more. 

As for the parts on the under ^ surface around the 
head, in some animals these are formed like gills so as 
to let in the water and to discharge it ; the lower 
parts, however, of female crabs are flatter in formation 
than those of male ones, and also the appendages on 
the flap are hairier. This is because they deposit 
their eggs there instead of getting rid of them, as the 
fishes and the other oviparous animals do. These 
appendages are wider and larger and so can provide 
more space for the eggs. In all the Carabi and in 
all the Carcini the right claw is bigger and stronger 
than the left. This is because all animals in their 
activities naturally use the right side more ; and 
Nature always assigns an instrument, either ex- 
clusively or in a better form, to those that can use it. 
This holds good for tusks, teeth, horns, spurs and all 
such parts which serve animals for assistance and 

In Lobsters only, whether male or female, it is 
a matter of chance which claw is the bigger. The 

* Probably the spiny spider-crab. 
^ That is, ventral. 



684 a ^ 

dppeve?. a'iriov he rod fxev ^x^lv xV^^^ otl iv rco 

35 yeVet etcrt tco exovri xV^^^' tovto 8* OLTOLKrcos 
684 b exovuLV on TreTTrjpojvraL Kal ov ;)^pcDvTat e(/)* o 
7T€(f)VKaGLV, qAAo, TTOpelag x^P^^- 

Ka^' eKaGTOV he tujv fiopicxjv, rig rj deuig avrcov 

Kal riveg hLacf>opal irpos d'AA^^Aa, rojv r d'AAcov /cat 

TLVL SiacfyepeL to, dppeva rcov drjXeiwv, €K re ra)v 

5 dvaropLCJV deojpeiaBuj /cat e/c rcov tcrroptcov rttjv 

Trept Tct ^a)a. 

IX. Tcov he jJLaXaKLOJv rrepl fiev roJv ivros 
elpiqraL Trporepov, ojanep Kal nepl rcov ctAAcov 
t^ipiov eKTos S' e;!^ft to re rou crcujLtaros" KVTOSy 
dhiopiGTov 6v, Kal rovrov vohag epLTrpoodev Trepl 
Tr)v Ke(f)aXrjV, evros jJLev raJv 6(f)daXfia)Vy Trepl he 

10 TO GTOjJLa Kal Tovg ohovras. rd fxev ovv dXXa t,cpa 
rd exovra rrohag rd jjiev efXTrpoGdev e;^et /cat 
oTTLGdev, rd 8' e/c rod irXayiov, ojorrep rd TToXvTroha 
Kal dvaijia rcov ^cocov rovro he ro yevog Ihlojg 
rovrcov rrdvras ydp exovGL rovs rrohas errl ro 
KaXovpuevov ejiTrpoGOev. rovrov 8' atrtov on 

15 GVvrJKraL avrcov ro OTTLoOev rrpos ro efirrpoGdev, 
wGTTep rdjv oGrpaKoheppicov rots GrpofM^ajheoLV. 
oAoJS" ydp rd oorpaKohepi^ia ex^L rfj fiev opLOLOJS 
rots' piaXaKOGrpaKois , rfj he roZs jLtaAa/ctot?. fj 
fxev ydp e^ojdev ro yecoheg evrog he ro oapKcbhe?, 
rols jLtaAa/coCTTpd/cots", to Se gx'^P-ol rod o-aj/xaros" 

20 ov rpoTTOV GvveGrrjKe, rolg ^aAa/ctots", rpoirov fiev 

« See Hist. An. 525 a 30—527 b 34, 541 b 19 ff. 

^ At 678 b 24 ff. 

'^ The theory that the cuttle-fish is comparable to a verte- 
brate bent double was put forward in a paper read before the 
Academy of Sciences in 1830, and was the origin of the famous 

PARTS OF ANIMALS, IV. viii.-ix. 

reason why they have claws is because they belong 
to a group which has claws ; and tliey have them 
in this irregular way because they themselves are 
deformed and use the claws not for their natural 
purpose but for locomotion. 

For an account of every one of the parts, of 
their position, and of the differences between them, 
including the differences between the male and the 
female, consult the Anatomical treatises and the 
Inquiries upon Animals.'^ 

IX. With regard to the Cephalopods, their internal (i) Cephs 
parts have already been described, as have those ^°P°^^- 
of the other animals.^ The external parts include 

(1) the trunk of the body, which is undefined, and 

(2) in front of this, the head, with the feet round it : 
the feet are not beyond the eyes, but are outside the 
mouth and the teeth. Other footed animals either 
have some of their feet in front and some at the 
back ; or else arranged along the sides — as with the 
bloodless animals that have numerous feet. The 
Cephalopods, however, have an arrangement of 
their own. All their feet are on what may be 
called the front. The reason for this is that their 
back half is drawn up on to the front half,'^ just as 
in the conical-shelled Testacea. And generally, 
though in some respects the Testacea resemble the 
Crustacea, in others they resemble the Cephalopods. 
In having their earthy material outside and their 
fleshy material inside, they resemble the Crustacea ; 
but as regarding the formation and construction of 
their body they resemble the Cephalopods — -all of 

controversy between G. St-Hilaire and Cuvier about unity of 
type. This controversy excited Goethe more than the revolu- 
tion of the same year. (Ogle.) 

M 2 ' 355 


684 b 

TLva TTOLvray (jLaXiora he rcov oTpofx^coScov ra 

e^ovra rrfv iXiKrjv dfji(f)OT€pa)v yap tovtov €;(et 

rov TpoTTov 7) <j)vaLs^' et propter hoc ambulant uni- 

formiter {akX ovY KaOdnep avfjL^e^rjKev eirl rcov 

TcrpaTToScov t,cpa>v /cat rcov dvOpcjuTTCOv. homo vero 

25 habet os in capite, scihcet in parte superiori corporis, 
€7T€LTa rov arofiaxov, eVetra Se rrjv KOiXlav, oltto 8e 
ravrr]? to evrepov p-ixP^ '^V^ Ste^oSou rov irepir- 
rcofiaros. rovrov jxev ovv rov rpoTTOv e;^et roTs 
€vaLfjLOL9 ^cpoi?, Koi (i€rd r-qv KecffaXijv ioriv 6 KaXov- 
fxevo'^ Ocopa^, Kal rd nepl rovrov rd Se Xonrd jjiopia 

30 rovrojv re X^P^^ ^^^ eveKa rrjs Kiv-qoeojg TrpooedrjKev 
71 (f)VGis, olov rd re rrpoaOia KcJoXa /cat rd OTnadev. 
^ovXerai Se /cat rots' fiaXaKoarpaKoig /cat rot? 
ivrofioLS 'q y evOvajpca rcov evroodihicov rov avrdv 
€X€LV rpoTTov, /caTct Be rds vir-qpeoias rds e^codev 
KLvqrLKds hia(j)epeL rcov ivaipicjov. rd he /xaAct/cta 
re /cat (jd^^ arpopL^cohrj rcov oarpaKohepp^cov ex^i 

^ sequitur locus corniptus. quae corrigi possunt sec. vers, 
arabicam corrcxi, suppositicia eieci, amissa e versione latina 
Mich. Scot supplevi. text. vulg. habet tj <j)vais (Lc-rrep et tls 
vorjaei€V eV evdeias, KadaTrep avfi^e^rjKev eVi rcov TerpaTToBcov 
l,(x)wv Kal rcov avdpoiTTwv, TrpcjTov p.kv inl aKpco ro) avoj ard/xaTi 
rrfS €v9eias Kara to A, iTTura K^Kara. addunt PY> to B tov 
OTOfxaxov, [to 8e om. PY] V rrjv KOiXiav oltto Sc tov ivripov 

fl^Xpi' TTJS 8l€^680V tov TTepiTTCOjJLaTOS, 1^ TO A. TOVTOV fxkv OVV 
TOV TpOTTOV eX^L TOls (.VaijXOlS t,a)OLS, KOI TT€pl TOVTO ioTlV lj 

K€(f)aXrj KOL 6 dcopa^ Ka\ovp.evos {koX, dcopa^ SU)* to. 8e Xonrd, 
etc. vide et quae p. 432 scripsi. 

2 <dAA' ov> Peck. 3 <Ta> Peck. 



them do so to some extent, but most markedly 
those conical Testacea which have a spiral shell, 
since both these classes have this natural struc- 
ture * ; and therefore they walk with an even gait, 
and not as is the case with quadrupeds and man.^ 
Now man has his mouth placed in his head, viz. in the 
upper pari of the body, and after that the gullet, then 
the stomach, and after that the intestine which 
reaches as far as the vent where the residue is dis- 
charged. This is the arrangement in the blooded 
animals, i.e., after the head comes what is known as 
the trunk, and the parts adjoining. The remaining 
parts {e.g. the hmbs at front and back) have been 
added by Nature for the sake of those which I have 
just mentioned and also to make movement possible. 
Now in the Crustacea too and in the Insects the 
internal parts tend to be in a straight alignment of 
this kind ; though with regard to the external parts 
which subserve locomotion their arrangement diifers 
from that of the blooded animals. The Cephalopods 
and the conical-shelled Testacea have the same 

" The passage which follows has been badly corrupted by 
references to a diagram which have ousted the text. The 
words in itaHcs have been translated from the Arabic version, 
of which Michael Scot's Latin translation is given opposite, in 
default of the original Greek. See supplementary note on 
p. 432. 

* This refers to their uneven progression by moving first 
one side of the body and then the other. The Testacea, how- 
ever, " have no right and left" {De incessu an. 714 b 9), and 
their movement was evidently an awkward problem for 
Aristotle. He reserves them until the very end of the De 
incessu, and he has to admit that they move, although they 
ought not to do so ! They move Trapa <^volv. The mechan- 
ism of their motion can be detected by the microscope, and is 
known as ciliary. See also De incessu^ 706 a 13, 33, Hist. 
An. 528 b 9. 

' 357 


885 a avTols fj,€V TrapaTrX-qoiajg, tovtols 8' dvrearpa^' 
/xeVojs" KeKafiTTrai yap rj reXevrrj Tvpos rrjv dp)(rjv, 
a)07r€p dv et Tt? ttjv evOelav [icf)^ rjs to E]^ Kafiipas 
TTpooaydyoL to A Trpog to A. ovtcos ydp Keifievajv 
vvv Tcov ivrooOicov TrepiKeirai toIs /xev /xaAa/ciotS" to 
.'■) KVTOSy o KaXetTai [jlovov irrl tcov rroXvrrohojv K€(f)aXy]- 


jSo?. Sta^epet S* ovSev dXXo ttXtjv on roZs p-kv 
pLoXaKov TO TTepi^, Tols Se GKX-qpov -rrepl ro aapKwhes 

TT€pieOr]K€V T] (f)VOLS, OTTOJS GOjt,iqTai hid TTjV SvGKLVT]- 

Giav Kal Sid TOVTO to TrepLTTCjpia rots re paXaKiois 
10 i^epx^Tat 7T€pl to GTop^a Kal tols GTpopftcLheGi, 
ttXtjv roXg pikv piaXaKLOLS KarcodeVy toIs 8e GTpop- 
jScoSeatv e/c tou irXayiov. 

Ata TavTTjv pikv ovv ttjv alriav toIs piaXaKiois ot 


t} TOts" d'AAot?. exovGi 8' dvopoiws at Gr^Triai Kal 

15 at revOiSes TOt? ttoXvttogl Sid to vevGTiKal povov 

€tvat, Tous" 8e Kal TTopevTiKovg. at pikv ydp Toug 

dvcvdev rd)V ohovTWV (e^ puKpovsY e;(ouo-t, /cat 


TCOV OKTOJ Svo Karwdev peyiGTOV? rrdvrojv.^ coGTrep 
ydp TOt? TeTpaTTOGi to. ottlgO ia iGxvpoTepa /ctoAa, 
Kal ravTais piiyiGTOi ol Karcodev (77-o8es')'** to ydp 

20 (f)OpTiOV OVTOi eXOVGi Kal KiVOVGL pidXiGTa. Kal Oi 

^ seclusi ; post ^s add. Z to o\ov (f>r)aL. vid. p. 432. 

^ Schneider ex Gazae vers, {senos exiguos) ; sex S ; fxiKpovs 
Z (sed noBa)v pro oSovtcov), idem E teste Buss. 

^ TT-avTcov Ogle : TovTcvv vulg. * <7ro8es'> Rackhani. 



arrangement as one another, but it differs completely 
from that of the others, as the tail-end of these 
creatures is bent right over to meet the front, 
just as if I were to bend the straight hne over 
until the point D met the point A. Such 

A B C D 

then, is the disposition of their internal parts. 
Round them, in Cephalopods, is situated the sac (in 
the Octopuses and in them only it is called the head) : 
in the Testacea the corresponding thing is the conical 
shell. The only difference is that in the one case 
the surrounding substance is soft, and in the other 
Nature has surrounded the flesh with something 
hard, to give them the preservation they need owing 
to their bad locomotion. As a result of the above- 
mentioned arrangement, in both sets the residue 
leaves at a point near the mouth : in the Cephalopods 
under the mouth, in the conical Testacea at the side 
of it. 

So what we have said explains why the feet of 
Cephalopods are w^here they are, quite differently 
placed from all other animals' feet. Sepias and 
Calamaries, however, being swimmers merely, differ 
from the Octopuses, which are walkers as well ; they 
have six small feet above the teeth, and of these the 
ones at each end are larger ; the remaining two out 
of the total eight are down below and largest of 
all. These creatures have their strongest feet do^v^l 
below, just as quadrupeds have their strongest limbs 
at the back ; and the reason is that they carry the 
weight of the body and they chiefly are responsible 
for locomotion. The two outer feet are larger than 
the inner ones because they have to help the others 

' 359 


685 a 

VTTrjperovorLV. 6 8e ttoXvttov? tous iv fieuo) rerrapas 


IloSa? fi€V ovv TTOLvra exovat ravra oktw, dAA' 
at /xey o-qTriai koL at revOcSes ^pax^ls, ra he 
TToXvTToScoSr] /xeyaAous". to yap kvtos rod crajjuaro? 

25 at pL€v fieya exovauv ra} he puKpov, cuare rots' ftey 
a^etAev aTro rod Gcofxaros, Trpos he to jjltjkos tcov 
7Toha)V TTpoaeOr^Kev rj (f)VGi?y rat? 8' oltto tcov 
TTohcov Xa^ovaa to oajfia -qv^-qaev. hionep TOt? 
fiev OX) pLovov TTpos TO veZv xPV^^l^ot, OL vohes dXXa 
Kal TTpos TO ^ahi^eiv, Tat? S' dxpr](JTOL' puKpol yap, 

80 TO he KVTOS /xeya exovacv. eVet Se jSpa^^et? exovoL 
Tovs TTohas /cat d;^p')70'T0us" Trpos to dvTiXapi^dveodaL 
Kal fir) dirooTTaodai^ diro tojv TreTpojv, OTav KXvhojv 
fj Kal ;!^6tjLtcuv, Kal rrpos to to. aTToOev tt poody eodai, 
hid TavTa rrpo^ooKihas exovai hvo paKpds, at? 

35 oppiovoi Te Kal dTTooaXevovoiv wGrrep rrXolov orav 
685 b x^^^dov fjy Kal Td aTToBev OrjpevovGi Kal TrpoudyovTai 
TavTais at Te arjTTiai Kal at revdlhes- ol he ttoXv- 
TTohes ovK exovGi to,? Trpo^ooKihas hid to tovs 
rrohas avTols elvai irpos TavTa XPV^^I^^^^' ^vlols^ 
he KOTvXrjhoves Trpos TOt? Troat /cat TxAe/CTavat 
6 TTpooeioLy hvvapLiv exovGai* Kal ovvdeuiv TOLavTr]v 
otavTrep rd TrXeypLaTia ols ol larpol ol dpxouoi tovs 
haKTvXovs eve^aXXov ovtoj Kal e/c tcov Ivcjv 

^ Ttt Peck : ol vulg. 

* dnoaTTdadai Bckker : avriaTrdadai codd. 

^ ivlois Peck : oools vulg. 

* ^Xovaai P : exovai vulg. 

" The use of these aavpai or aeipat is described by Hippo- 
crates, Ucpl dpdpcov (Littre iv. 318-330 ; L.C.L. iii. 390 : " The 
tubes woven out of palm-tissue are satisfactory means of 


in performing their duty. In the Octopuses, however, 
the four middle feet are the biggest. 

And although all these creatures have eight feet, 
the Sepia's and the Calamary's are short ones, since 
their bodies are large in the trunk, and the Octopus's 
feet are long, because his body is small. Thus in 
one case the substance which she took from the body 
Nature has given towards lengthening the feet, and 
in the other she has taken away from the feet and 
made the body itself bigger. Hence it results that 
the Octopuses have feet which will serve them for 
walking as well as for swimming, whereas the other 
creatures' feet will not do so, being small, while the 
body itself is big. And inasmuch as these creatures' 
feet are short, and useless for holding on tightly to 
the rock in a storm when there is a strong sea running, 
or for bringing to the mouth objects that are at a 
distance, by way of compensation they have two long 
probosces, with which during a storm they moor 
themselves up and ride at anchor like a ship ; there- 
with also they hunt distant prey and bring it to their 
mouths. These things the Sepias and Calamaries 
do. The Octopuses have no probosces because their 
feet serve these purposes. Some creatures have 
suckers and twining tentacles as well as feet : these 
have the same character and function as well as the 
same structure as those plaited tubes which the early 
physicians used for reducing dislocated fingers." They 
are similarly made out of plaited fibres, and their 

reduction, if you make extension of the finger both ways, 
graspins: the tube at one end and the wrist at the other." 
The aavpa was thus a tube open at both ends. A similar 
passage in Diodes ap. Apollonius of Kitium, no doubt taken 
from Hippocrates, refers to " the aetpai which children plait " 
(L.C.L. iii. 453). 

. 361 


685 b 

TreTrAey/xeVat elalv^ Kal^ eXKOvai ra aapKca /cat 
TO, ivSiSovTa. 7TeptAa/x/3avet /xev yap ^(^aXapa ovra* 
orav 8e ovvrelvr), Tiie^et Kal €-)(€TaL rod eyros" 
diyydvovros Travros. 

10 "ncrr' eVet d'AAo ovk eoTLV cL TTpoad^ovraL, aAA* 
7] rd fX€v ToZs TToal rd 8e rat? TTpo^ouKiGi, rauras 
exovGi TTpds d\K7]V Kal ttjv dXXrjv ^orjOeiav^ dvrl 

To, fxev ovv dXXa SiKorvXd ion, ylvos he rt ttoXv- 
rrohcov piovoKorvXov. alnov Se to firJKOS Kal rj Actt- 
roTTjs Tr]g (/jvaeajs avrdjv {jlovokotvXov ydp dvay- 

15 Kalov elvai rd orevov. ovk ovv ojs ^eXriarov exovauv, 
dXX (Ls dvay Kalov Std rdv lSlov Xoyov r7]s ovolas. 

Urepvyiov 8' exovoL ravra rrdvra kvkXo) Trepi to 
KVTOS. rovro 8' irrl fjiev rdjv dXXcov uvvaTrropLevov 
/cat Gvvex^9 eon, Kal IttI tojv pLeydXwv revOcov 
at 8' iXdrrovs Kal KaXovfievat revOlSeg TrXarvrepov 

20 re rovro exovGL Kal ov orevov, a)07T€p at ar^TTiai 
Kal ol TToXvTToSes, Kal rovr dird piioov -qpyp.evov, 
Kal ov kvkXo) 8ta iravros. rovro 8' exovaiv 
O7TC0S vecooL Kal TTpds TO Siopdovv, (x)a7T€p roLS fJLev 
TTTqvots TO oppoTTvyiov, rots 8' IxOvcn to ovpalov. 
iXaxiorov 8e rovro Kal TJKLora eTrihiqXov rols 


hiopdovodai rots ttooIv t/cavcos". 

He pi fjL€V ovv TOJV ivTOfxcov Kal fiaXaKoarpaKOJV 
Kal OGTpaKoBepfjiOJV Kal [jiaXaKLOJV eiprjrai, Kal 
7T€pl Twv ivrds fiopiajv Kal rcov cktos. 

80 X. HaAtv 8' e^ VTTapxrjs vepl raJv ivaipaxiv /cat 

^ Kal Ogle : aU vulg. 
^ aXKriv xP^io-v Kal ^oi]deiav Y, Ogle. 



action is to draw flesh and yielding substances, as 
follows. First they encircle the object while they 
are still relaxed ; then they contract, and by so doing 
compress and hold fast the whole of whatever is in 
contact with their inner surface. 

So, as these creatures have nothing else with which 
to convey objects to the mouth except the feet (in 
some species) and the probosces (in others), they 
possess these organs in lieu of hands to serve them 
as weapons and generally to assist them otherwise. 

All these creatures have two rows of suckers, except 
a certain kind of Octopus, and these have only one, 
because owdng to their length and slimness they are 
so narrow that they cannot possibly have another. 
Thus they have the one row only, not because this 
arrangement is the best, but because it is necessitated 
by the particular and specific character of their being. 

All these animals have a fin which forms a circle 
round the sac. In most of them it is a closed and con- 
tinuous circle, as it is in the large Calamaries (teuthi), 
while in the smaller ones called teuthides it is quite 
wide (not narrow as in the Sepias and Octopuses), 
and furthermore it begins at the middle and does not 
go round the whole way. They have this fin to 
enable them to swim and to steer their course, and 
it answers to a bird's tail-feathers and a fish's tail- 
fm. In the Octopuses this fin is extremely small and 
insignificant because their body is small and can 
be steered well enough by means of the feet. 

, This brings to an end our description of the internal 
and external parts of the Insects, the Crustacea, the 
Testacea, and the Cephalopods. 

X. Now we must go back and begin again ^vith 

. 363 


685 b , , , , > , , ^ ^ f 

i,ci)OTOKOJV eTTiGKeTTTeov, ap^aixevoLS aire rcov vtto- 
Xolttcjov Kal TTporepov €lpr)[jLevojv pLopicjv tovtcov 8e 
SiopLoOevrcov Trepl rCov ivaLficov Kal cootokojv tov 
avTov rpoTTOV epovpiev. 

Ta pLev ovv pLopia ra Trepl rrjv Ke(f)aXrjV rwv ^wcjov 

35 eiprjrai rrporepov, Kal ra Trepl tov KaXovpievov 

avx^^oL Kal Tpdx^Xov. ex^t Se Ke(j)aXr]v Trdvra rd 

686aeVat/xa ^cpa- rcov 8' dvaipiojv eviois dhLopiorov 


TO. fiev t^cpoTOKa tto-vt 'ex^^> tojv S' cootokcov to, 

pLev ex€L TO. o' ovk e^er oaa puev yap TTvevpLova 

6 e'xet, Kal avx^vo. ex^i, tcl he purj dvaTTveovTa 6-6 pad ev 


"EcTTt 8' Tj pLev Kecl)aXrj pLaXidTa tov eyKe(j)dXov 
XdpLV dvayKT] yap tovto to pLoptov ex^^v Tolg iv- 
aipiois, Kal iv avTiKeipLevco tottco ttjs KapSlag, 
8td TOLS elprjpievas TrpoTepov atrta?. e^eOeTO 8' t] 
10 (f)VGis ev avTjj Kal tojv aLadrjaecuv evta? Sid to 
GvpLpLeTpov etvai ttjv tov a'lpiaTOS Kpdoiv Kal evn- 
rrjSeiav npos re ttjv tov iyKe(f)dXov dXeav Kal 
TTpos TTJV TciJv oloQ'qoeojv rjavx^oLV Kal dKpi^eiav. 

€TL 8e TpLTOV pLOpLOV VTTedrjKe TO T'r]V TTJS TpO(f>rJ9 

CLGoSov hiqpiovpyovv evTavOa ydp VTreKeiTO ovpu- 
pieTpcos pidXiGTa- ovTe ydp dvojdev KeloOai ttjs 
15 KapSias Kal ttjs dpx^s evehex^ro ttjv KoiXiav, ovTe 
KdTwdev ovo7]s ov TpoTTOV e^^et vvv iveSex^TO ttjv 
etcro8ov ert /caroj etvau t-:^? KapSlas' ttoXv ydp dv^ 


Kivovoris dpxT]S Kal TreTTOvor^s . r) pev ovv Ke(f)aXrj 

TOVTCOV xdpiv eGTLV, 6 8' avx'Tjv TTJs" dpTTipias ;^aptv 

^ av P, om. vulg. 


the blooded viviparous animals. Some of the parts 
Mhich we have already enumerated still remain to 
be described, and we will take these first. This 
done, we will describe similarly the blooded Ovipara. 

We have already " spoken of the parts around the External 
head, and what is called the neck, and the throat. I'.looded 
All blooded animals have a head, but in some of the animals. 
bloodless ones the head is indistinct {e.g. in crabs). " ^^^^^ 
All Vivipara have a neck, but not all Ovipara : to 
be precise, only those which breathe in air from with- 
out and have a lung. 

The presence of the head is mainly for the sake of Sead and 
the brain. Blooded creatures must have a brain, 
which (for reasons aforeshown) ^ must be set in some 
place opposite to the heart. But in addition, Nature 
has put some of the senses up in the head, apart from 
the rest, because the blend of its blood is well pro- 
portioned and suitable for securing not only warmth 
for the brain but also quiet and accuracy for the senses. 
There is yet a third part which Nature has disposed of 
in the head, viz. the part which manages the intake 
of food ; it was put here because this gave the best- 
ordered arrangement. It would have been impossible 
to put the stomach above the source and sovereign ^ 
part, the heart ; and it would have been impossible 
to make the entrance for the food below the heart, 
even with the stomach below the heart as it actually 
is, because then the length of the body would be 
very great, and the stomach would be too far away 
from the source which provides motion and concoc- 
tion. These then are the three parts for whose sake 
the head exists. The neck exists for the sake of the 

" At 655 b 27—665 a 25. ^ At 652 b 17 ff. 



686 a ^ 

20 TTpo^X-qjxa yap ccttl, kol gcjoI,€L ravTqv kol rov olcro- 

<f)dyov kvkXco nepLexcov. rols /xev ovv d'AAots" ecrrt 
KapLTTTos KOL G(f)ovSvXovs €)(a>v , ol 8e XvKOL Kai 
XiovTCs pLOVOGTovv Tov av^^va ex^vGiv. e^Xeifje 
yap 7) (f)vaLg ottojs rrpos rrjv laxvv ;^p7]CTt/xoy avTOV 
excoGi jLtaAAov ^ Trpos ras d'AAa? ^orjOelas. 

'E;^o/xeva 8e rov avx^vos Kal rrjs K€(f)aXrjs rd re 

25 7T pood la KcoXa rols ^cool? iorl Kal Owpa^. 6 p,€V 
ovv di'dpcoTTo? dvTL oKeXojv Kal TToSiJjv Tcov TTpoadiajv 
PpaxLovag Kal rds KaXovpievas ex^i ;\;6tpas'. opOov 
fiev ydp ian piovov rojv t,a)Cx)v hid to ttjv (J)VGLv 
avTOV Kal rrjv ovaiav elvai deiav epyov 8e rov 
deiordrov to voelv Kal cfipovelv tovto 8' ov paScov 

so TToXXov TOV dvcodev erriKeipiivov awp-aTOS' to ydp 
^dpos hvGKivif]Tov rroiei ttjv Scdvoiav Kal rrjv 
KOLVTjv aludr]GLV. hid irXeiovos yivopiivov tov 
^dpovs Kal tov ocopLaTixihovs dvdyKT] peTreiv rd 
GcopiaTa TTpos Triv yrjv, (Lgtc irpos ttjv docjidX^iav 
dvrt ^paxidva>v Kal x^^pdjv tov? TTpoGdtovs TToSas 

35 vveOrjKev rj (jiVGis Tolg TeTpdrroGLV. tovs /Lcev 
686 b ydp ottlgOlovs hvo rraGiv dvayKaZov toIs TTopev- 
TiKoZs ^X^^^> Td he ToiavTa TeTpdiroha iyeveTO ov 
hvvapiivrjs ^ipeiv to ^dpos ttjs i/jvxrjs- "rravTa ydp 
€GTL Td Ja>a vavajh-q rdAAa Trapd tov dv6pa>7TOV 
vavcbhes ydp Igtiv ov to /xev dvoj pLeya, to he 

6 <f)epov TO pdpos Kal Tre^evov puKpov dvoj 8' eVrtv 
d KaXovpLevos dcnpa^, ajro ttJ? KecjyaXrjS i^^X/^t '^'^S' 

" For the " general " or " common " sense see De mem. 
450 a 10, etc. ; and cf. Be part. an. 656 a 28, 665 a 12. The 
" general " sense is not another sense over and above the 
ordinary five, but rather the common nature inherent in 



windpipe : it acts as a shield and keeps the windpipe 
and the oesophagus safe by completely encircling 
them. The neck is flexible and has a number of 
vertebrae in all animals except the wolf and the lion 
whose neck consists of one bone only, for Nature's ob- 
ject was to provide these with a neck that should be 
useful for its strength rather than for other purposes. 

The anterior limbs and the trunk are continuous Limbs, and 
with the head and neck. Man, instead of forelegs reia'tive 
and forefeet, has arms and hands. Man is the only sizes, 
animal that stands upright, and this is because his 
nature and essence is di\ine. Now the business of 
that which is most divine is to think and to be intelli- 
gent ; and this would not be easy if there were a great 
deal of the body at the top weighing it down, for 
weight hampers the motion of the intellect and of the 
general sense.'* Thus, when the bodily part and the 
weight of it become excessive, the body itself must 
lurch forward towards the ground ; and then, for 
safety's sake, Nature provided forefeet instead of 
arms and hands — as has happened in quadrupeds. 
All animals which walk must have two hind feet, and 
those I have just mentioned became quadrupeds be- 
cause their soul could not sustain the weight bearing 
it doAMi. Compared with man, all the other animals 
are dwarf-like. By " dwarf-like " I mean to denote 
that M'hich is big at the top (i.e. big in the " trunk,'* 
or the portion from the head to the residual vent), 
and small where the weight is supported and where 

them all ; thus Aristotle {De somno) argues that their simul- 
taneous inactivity during sleep is not a mere coincidence but 
is due to the inactivity of the central perceptive faculty of 
which they are differentiations. Among the functions of the 
" general " sense are : discrimination between the objects of 
two senses, and the perceiving that we perceive. 

' 367 


686 b ^ 

i^oSov rod TrepLrrcjofxarog. rot? fikv ovv avBpcjTTOi^ 
rovTO irpos to Karco ovpLi-ierpov, kol ttoXXco 
eXarrov eon reXeiovpiivois' veois S' ovui rov- 
vavTLOV ra fiev avoj fxeydXa, to 8e Karoj puKpov 

10 (8to Kal epnovcri, ^ahil,eLV S' ov hvvavrai, to Se 
7Tpa>Tov oz58' epTTovGiv, a\X aKLViqTit,ovuiv)' vdvoi 
yap elcTL rd Traihia Trdvra. rrpoCovoi he roZs p-ev 
dvdpojTTOis av^erai rd Kdrojdev rol? Se rerpdnoai 
TovvavTLOV rd Kdrco pLeyiura rd rrpajrov, Trpo'Covra 
S' av^erat errl rd dvoj, rovro 8* eorl rd and rrjg 
eSpag errl rrjv KecjjaXr^v Kvros. hid Kal ro) vifjei ol 

15 77-coAot TcDy LTTTTajv ovSev rj piLKpdv eXdrrovs elai, 
Kal veoL p,ev dvres diyydvovGi red oTTiaBev GKeXei 
rrjs K6(f)aX7Js, Trpeo^vrepoi 8' ovres ov hvvavrai. 
rd (lev ovv pLcovvxoL Kal St^i^Aa rovrov ex^L rdv 
rpoTTOVy rd Se 77oAu8a/<:Ti'Aa Kal aKepara vavajSrj 
fjLev eoriv, rjrrov he rovrcov hid Kal rrjv av^rjatv 

20 Trpos" rd dvoj rd Karco Kard Xoyov TTOielrai rijs 

"Kan he Kal rd rwv opvldojv Kal rd rcov Ix^vojv 
yevos Kal Trdv rd evaipLOv, wcnrep eiprjrai, vavcohes. 
hid Kal d^poveorepa Trdvra rd t,ci)a rcov dvOpcoTTCOv 
ear LP. Kal ydp rcdv dvOpcvTrcov, olov rd re rraihia 
rrpds rods dvhpas Kal avrajv rcov ev -qXiKia ol 

25 vavcohei? rr]v ^vglv, edv Kal riv^ dXXrjv hvvap,LV 
exwoL TTepurr-qv, dXXd rep rdv vovv e;^€t.v iX- 
XeiTTOVGLv. atriov 8', WGnep etprjraL npdrepov, on 
7] rrjs ijjvx'TJS dpx'Tj ttoXXoXs hrj^ hvGKLvqros eon 
Kal GCopLarcvh-qs. eVt 8' eXdrrovos yLvop,evr)s rrjs 

^ TToXXols hi) Peck : -noXXo) Srj vi\]p. : add. Kal Y, Piatt, qui 
et insuper addit (^apd aiofiaTi Karate pofiimj). 


locomotion is effected. In man, the size of the trunk 
is proportionate to the lower portions, and as a man 
^rows up it becomes much smaller in proportion. 
In infancy the reverse is found : the upper portion is 
large and the lower is small (and that is why infants 
cannot walk but crawl about, and at the very be- 
ginning cannot even crawl, but remain where they 
are). In other words, all children are dwarfs. Now, 
in man, as time proceeds, the lower portion grows : 
Not so with the quadruped animals : their lower 
portion is biggest at the beginning, and as time 
proceeds the top portion grows (i.e. the trunk, the 
portion between the head and the seat). Thus foals 
are quite or almost as high as horses, and at that age a 
foal can touch its head with its hind leg, but not when 
it is older." \\Tiat has been said holds good of the 
animals that have solid hoofs or cloven. The poly- 
dactylous, hornless animals are indeed dwarf-like 
too, but not so markedly, and so the growth of their 
lower portions compared with the upper is propor- 
tionate to the smaller deficiency. 

The whole groups of birds and fishes are dwarf-like ; 
indeed, so is every animal vnth blood in it, as I have 
said. This is why all animals are less intelligent than 
man. Even among human beings, children, when 
compared with adults, and dwarf adults when com- 
pared with others, may have some characteristics in 
which they are superior, but in intelligence, at any 
rate, they are inferior. And the reason, as afore- 
said, is that in verv many of them the principle of the 
soul is sluggish and corporeal. And if the heat which 

" These observations are entirely correct. Cf. Ogle's 
quotation ad loc. from T. H. Huxley. See also Hist. an. 
500 b 26 ff. 

' 369 


686b ^ ^ 

alpovurjs OepiioTrjTOS koL rod yeojSovs TrXelovos, rd 

80 T€ (jco/JLaTa eXdrrova rcov t,a)OJv earl Kal TToXvrroha, 
Tf.Xos 8' ctTToSa yiverai Kal rerafiiva irpos rrjv yrjv. 
jJLLKpov S' ovTCO TTpo^aivovTa Kal rriv dpxV'^ exovGL 
KOLTO), Kal TO Kara rrjv K€(f)aXrjv pLoptov reXog 
OLKLvrjTov iari, Kal dvaLGdrjrov, Kal yiverai (fyvrov, 

85 €xov rd fjLev dvco Kdrw, rd he Kdrco dvoj' at ydp 
pl^aL rots (f)VTol9 GTopiaTog Kal K€(f)aXrjg 'ixovai 
SS7 a SvvapLLv , TO Se airipp^a rovvavriov dvo) ydp Kal 
€77* aKpoLs yiverai roZs Trropdoig. 

At' rjv puev ovv alriav rd fiev StVoSa rd Se ttoXv- 
TToSa rd 8' a77oSa rcov i,ci)a)v ecrrl, Kal 8ta rlv 
alriav rd fxev <j)vrd rd he Joja yeyovev, eLprjraL, 
6 Kal 8toTt pLovov opdov iarL rcov t,a)(jov 6 dvdpwiTos' 
opdcp 8' ovrt rrjv cf)VGLV ovhepLia XP^^^ UKeXcov rcov 
epLTTpoodicov, dXX dvrl rovrcov ^pax^ovas Kal ;(etpa? 
aTTohehcoKev rj (f)VGL£. ^Ava^ayopas piev ovv <f)y]oi 
hid rd x^^poi? ^X^'-^ (j)povL[jLcorarov etvat rcov l^cocov 
dvOpcoTTOV evXoyov he hid rd cfipovipLcorarov elvai 

10 x^^P^^ XajjL^dveiv. at fxev ydp ;)(etpe? opyavov 
eloiv, T) he <j)VGis del hiavepiei, Kaddirep dvdpcoiTOS 
<j)p6vLpL09, eKaorov roj hvvajjievcp ;^p^(T^at [irpoa- 
rjKeL ydp rep ovrt avXrjrfj hovvai pidXXov avXov? 
rj ro) avXovs exovri Trpoadelvai avX-qriKi^v)- rep yap 
pLel^ovi Kal Kvpicorepcp npoaedriKe rovXarrov, dAA' 

15 ov ro) iXdrrovL rd rupLLcorepov Kal /xet^ov. el ovv 
ovrco? l^eXnoVy rj he (jyvais eK rcov evhexopevcov 

<* With the terminology used in 11. 28-29 cf. Hippocrates, 
TlipX StatTTj?, i. 35. 

^ That is, it answers to residue in animals ; cf. 655 b 35. 


raises the organism up wanes still further while the 
earthy matter waxes,*^ then the animals' bodies wane, 
and they will be many-footed ; and finally they lose 
their feet altogether and lie full length on the ground. 
Proceeding a little further in this way, they actually 
have their principal part down below, and finally the 
part which answers to a head comes to have neither 
motion nor sensation ; at this stage the creature 
becomes a plant, and has its upper parts below and its 
nether parts aloft ; for in plants the roots have the 
character and value of mouth and head, whereas the 
seed counts as the opposite,^ being produced in the 
upper part of the plant on the ends of the twigs. 

We have now stated why it is that some animals 
have two feet, some many, some none at all ; why 
some creatures are plants and some animals ; and 
why man is the only one of the animals that stands 
upright. And since man stands upright, he has no 
need of legs in front ; instead of them Nature has 
given him arms and hands. Anaxagoras indeed 
asserts that it is his possession of hands that makes 
man the most intelligent of the animals ; but surely 
the reasonable point of view is that it is because he 
is the most intelligent animal that he has got hands. 
Hands are an instrument ; and Nature, like a sen- 
sible human being, always assigns an organ to the 
animal that can use it (as it is more in keeping to 
give flutes to a man who is already a flute-player 
than to provide a man who possesses flutes with the 
skill to play them) ; thus Nature has provided that 
which is less as an addition to that which is greater 
and superior ; not vice versa. We may conclude, then, 
that, if this is the better way, and if Nature always does 
the best she can in the circumstances, it is not true 

, 371 


TTOieL TO peAriGrov, ov oia ras ;^etpas' ecrrtv o 
avdpojTTOS ^povLjJLOjraros, dAAa 8ta to (f)povLfX(x)- 
rarov elvai rcov l,a)CDV e-)(^ei -x^elpag. 6 yap cfypovL- 
[jLcoTarog TrXeLGTOtg dv opydvois e-x^piqaaro KaXojs, 
20 rj Se X^^P eoLK€v elvat ov)( ev opyavov aAAd TToXXd' 
eon yap (hoTrepel opyavov npo 6pydva)V. tco ovv 
TrXeLorag Swajxevcp Se^aaOau re^vas to eVt 
irXeloTov rcx)v opydvcov XPW^H-^^ "^W X^^P^ drro' 

'AAA' ol Xeyovres (1)S GVvedTrjKev ov KaXws 6 

avdpcorros dXXd ■)(eLpiura ra)V t,(h(xJV [dvviToSrjrov 

25 re yap avrov elvai ^aoi /cat yvjJLvov /cat ovk 

exovra onXov irpos rrfv dXK-qv) ovk opdujs XeyovGiv. 

rd fjiev yap dAAa jLttW €;^et ^orjOeiav, /cat fiera- 

^dXXeadat dvrl ravrr)? irepav ovk €gtlv, dAA' 

dvayKalov ayorrep vrrohehepievov del Kadcvheiv /cat 

irdvra TrpdrreLv, /cat ttjv irepl to CTdj/.ta dXecvpav 

IXTjheTTore KaradeGOai, /xT^Se p.eraf^dXXeGdai o hi] 

30 Irvyxo-vev^ ottXov exov^' ro) Se dvOpcoTTCp rd? t€ 

687 b jSo7]^etas" TToAAds" e;i^ety /cat ravras del e^eGri 

pLera^dXXetv, eVt 8' ottAov olov dv ^ovXrjraL /cat 

OTTOU dv^ ^ovXrjTai ex^iv. rj yap X^^P ^^tt ovv^ /cat 

XV^'^ '^^^^ /cepas" yiverai /cat hopv /cat ^Icjiog 

/cat dAAo oTTOtoroui^ ottAov /cat opyavov rrdvra yap 

6 €GTai ravra Std to Trdvra hvvaGOai Xafi^dv€LV /cat 

ex^tv auTT^v ei)* 8e ovfxiiepiiqxdvqTaL^ /cat to etSo?'' 

Ti^ cf)VG€L rrjs x^tpds", Staiperr) yap /cat 77oAuaxtS'>ys" 

1 eTyy;^avev ev U^ : Tvyxdvci. €v Th. ; hic alia omnino 11 

2 ex'ov Z, et corr. U : l^cuv viilg. 

^ 07T0U av] OTTorai' Og'le. 

* CX^'-^ avTrjv eu P : ex^Lv Tavrrj vulg. 

^ "irvfifi€fXTix<ii'r]rai Ogle : ovfifieixrjxo-vfjadai vulg. 

« €?So9 /cat vulg. : elBos PSUYZ. 



to say that man is the most intelHgent animal because 
he possesses hands, but he has hands because he is the 
most intelligent animal. We should expect the most 
intelligent to be able to employ the greatest number 
of organs or instruments to good purpose ; now the 
hand would appear to be not one single instrument 
but many, as it were an instrument that represents 
many instruments. Thus it is to that animal (viz. 
man) which has the capability for acquiring the 
greatest number of crafts that Nature has given that 
instrument (viz. the hand) whose range of uses is the 
most extensive. 

Now it must be wrong to say, as some do, that 
the structure of man is not good, in fact, that it is 
worse than that of any other animal. Their grounds 
are : that man is barefoot, unclothed, and void of 
any weapon of force. Against this we may say 
that all the other animals have just one method of 
defence and cannot change it for another : they are 
forced to sleep and perform all their actions with 
their shoes on the whole time, as one might say ; 
they can never take off this defensive equipment of 
theirs, nor can they change their weapon, whatever 
it may be. For man, on the other hand, many 
means of defence are available, and he can change 
them at any time, and above all he can choose what 
weapon he will have and where. Take the hand : 
this is as good as a talon, or a claw, or a horn, or again, 
a spear or a sword, or any other weapon or tool : 
it can be all of these, because it can seize and hold 
them all. And Nature has admirably contrived the 
actual shape of the hand so as to fit in with this 
arrangement. It is not all of one piece, but it 
branches into several pieces ; which gives the possi- 



687 b ^^ ^ ^ ^ 

eVt yap iv ro) SiaLperrjv elvat /cat avvderrjv elvai, 
iv TovTcp S' €K€LVO ovK eoTiv. KOI )(prjadaL ivl^ 

10 Kal Svolv Koi TToXXaxcog cGnv. /cat at Kafnral rcov 
SaKTvXojv KaXco? exovau irpos ra? Xijipei^ /cat 
TTieoeis. /cat e/c TrXayiov els, Kal ovros ^pa^vs 
/cat 7Ta)(vs dXX* ov fiaKpos' cooTrep yap et pjr] rjv 
X^i-P oXoj£, OVK av Tjv Xt^iJjl?, ovto) Kav el fir] eK 
TrXayiov ovros rjv. ovros yap KarcoOev dvo) TTte^et, 

15 onep at erepoL dvcodev Karco' Set 8e rovro ovpL^ai- 
vetv, el jLteAAet laxvpcog cjOTrep cuva/x/xa laxvpov 
GvvSetv, Iva lodt,rj els cuv ttoXXoIs. /cat ^pa^vs 
Sta re rr^v lgxvv Kal Stort ovSev 6(f)eXos el jxaKpos. 
(/cat o eaxoLTOS Se fiiKpos opOcos, Kal 6 fieaos 
fxaKpos, woTiep KcoTrr] peoovecos^' pLoXiura yap to 

20 XapL^avofxevov dvdyKrj TrepiXap^dveadaL kvkXco 
Kara to fieuov rrpos Tas epyauias) Kal Sta tovto 
/caAetrat p.eyas fxiKpos a)v, on dxp'^fyroi cLs 
elnelv ol d'AAot dvev tovtov. ev Se Kal to tcov 
ovvxo^v fjLep.rjxdvr]TaL' Ta pLev yap dXXa i^cpa ep^ct 
/cat TTpos XPV^''^ avTovs, toIs S' dvOpcoTTOLS em- 

25 KaXvTTTrjpia- cr/ceVaajLta yap tcov dKp(X)Tr]pia}v elaiv. 
At Se KapLTTal rcov ^paxi'Ovwv exovau rrpos re 
Tr]V rrjs Tpo(f)rjs Trpooaycoyrjv Kal irpos Tas aAAa? 
Xprjoeis evavTicos toZs TeTpdiroGiv. eKeivois fiev 
yap dvayKalov e'lacx) KdpLTrreiv Ta epLTrpoodia KCjXa 
{Xpa>vTai yap ojs^ ttouiv) tV 7^ xPl^^f^^ irpos Trjv 

^ ivl] Hid Ogle. 

^ fxeaoyecos Schneider : fxeoov veojs vulg. 

^ d)s r, om. vulg. 

" That is, the pieces. Ogle's suggested emendation 
would be translated " use the hands singly." The two 
transpositions suggested for this passage by Ogle seem un- 


bility of its coming together into one solid piece, 
whereas the reverse order of events would be im- 
possible. Also, it is possible to use them " singly, or 
two at a time, or in various ways. Again, the joints 
of the fingers are well constructed for taking hold 
of things and for exerting pressure. One finger is 
placed sideways : this is short and thick, not long 
like the others. It would be as impossible to get 
a hold if this Mere not placed sideways as if no hand 
were there at all. It exerts its pressure upwards 
from below, whereas the others act downwards from 
above ; and this is essential for a strong tight grip 
(like that of a strong clamp), so that it may exert 
a pressure equivalent to that of the other four. It 
is short, then, first, for strength, but also because it 
would be no good if it were long. (The end finger 
also is small — this is as it should be — and the middle 
one is long like an oar amidships, because any object 
which is being grasped for active use has to be 
grasped right around the middle.) And on this 
account it is called " bi"; " althouo;h it is small, be- 
cause the other fingers are practically useless without 
it. The nails, too, are a good piece of planning. In 
man they serve as coverings : a guard, in fact, for the 
tip of the fingers. In animals they serve for practical 
use as M-ell.^ 

The joints of the arms in man bend in the opposite 
direction to those of quadrupeds : this is to facilitate 
the bringing of food to the mouth, and other uses to 
which they are put. Quadrupeds must be able to 
bend their fore Hmbs inwards '^ so that they may be 
serviceable in locomotion, since they use them as 

'' That is, as tools. 
« See note on 693 b 3, p. 433. 

' 375 


687 b , , X / , , - \ ^ /\ 

so TTopclav, inel OeXei ye KOLKelvcov rols TToXvoaKTvAoLs 

ov JjLOVov TTpos TTjv TTopelav )(pr]GLfM etyat ra e/x- 
TTpooOev OKeXr), aAAa koI avri ;)(etpajv, cjOTrep /cat 
<f)aiv€TaL ;^pctjyneva' /cat yap Xaf-LpdvovGi /cat djLtu- 

688 a vovrai Tols TTpoodioLs. Tct 8e pLajw^a rols oTnadtoLS' 

ov yap ex^i avrols ret TrpoaOta gkIXt] avdXoyov rols 
ay/ccocrt /cat rat? x^P^^^- '^^^ ^^ TroAi'Sa/CTuAajv 
eVta /cat Sto. rovro /cat TrevraSa/cruAous' e;)(et Tot's" 
5 TTpoodiovs TToSas, Tou? 8* oTTLodev T€TpahaKTvXovs, 
olov Xeovres /cat Xvkol, ert 8e /ewe? /cat 77ap8aA€tc* 
o yap TTepLTTTOS coGirep 6 rrjs X^^P^^ yiverai pidyas 
[TTepLTTTOs']} rd 8e puKpd rcov TToXvhaKrvXojv /cat 
Tovs ottlgOlovs ex^i TrevraSaKTvXovs 8ta to 
ipTTvariKa elvai, orrcns rols ovv^i TrXeiooLv ovglv 
10 dvrcXapLpavopLeva paov dvepirrj irpos to pLerecopo- 
repov /cat vnkp Kecf^aXrj?. 

MeTa^-i) 8e rcov dyfcwvojv rols dvdpojTTOis, tols 
8* aAAot? Tcov ipLTTpoodicov GKeXojv, TO KaXovpi€vov 

GTTJdoS eGTly TOLS /XeV dvOpCOTTOLS ^xov nXdTOS €V- 

Xoyojs {ov yap kojXvovglv ol dyKcbves e/c TrXayiov 
TrpoGKelpevoL tovtov etyat tov tottov TrAaTuv), Tot? 

15 8e TeTpdlTOGL 8td TT^V €77t TO TTpOGBLOV TOJV KCvXoJV 

€KTaGLV iv TO) TTOpeveodaL /cat /xeTa^dAAetv tov 

TO, pL€V TETpdnoSa TCJV t,(I)(X)V OVK eX^L pLaGTOVS €V 

Xojplav /cat to CT/ceTTct^co^at 8etv to, Trept ttjv 
20 /capStav, 8td touto vndpxovTOS tov tottov oap- 


Tols p-ev dppeGL 8td TT^v elprjpLevTjv atTtav, e77t 8e 

^ TTeixTTTos seclusi. 


feet ; though even among quadrupeds the poly- 
dactylous ones tend to use the fore hmbs not only for 
locomotion but also instead of hands ; and this can 
actually be seen happening : they take hold of things 
and defend themselves with their fore limbs. (Solid- 
hoofed animals, on the other hand, do this with their 
hind limbs, as their forelegs have nothing that corre- 
sponds to elbows and hands.) This explains why 
some polydactylous quadrupeds actually have five 
toes on their forefeet (lions, wolves, dogs and leo- 
pards, for instance), although there are only four on 
their hind feet : the fifth one, like the fifth ^ digit 
on the hand, is a " big " one.^ However, the small 
polydactylous quadrupeds have five toes on their 
hind feet too, because they are creepers ; and this 
gives them more nails, and so enables them to get a 
better hold and creep up more easily to greater 
heights and above your head. 

Between the arms in man (in other animals be- Breast. 
tween the forelegs) is what is known as the breast. In 
man the breast is broad, and reasonably so, for the 
arms are placed at the side and so do not in any way 
prevent this part from being wide. In the quadru- 
peds, however, it is narrow, because as they walk 
about and change their position the limbs have to be 
extended forwards. And on this account, in quadru- 
peds, the mammae are not on the breast. In man, 
on the other hand, as the space here is wide, and the 
parts around the heart need some covering, the 
breast is fleshy in substance and the mammae 
are placed on it and are distinct. In the male they 
are themselves fleshy for the reason just given. In 

" Now generally called the " first." 
And needed when the foot is used as a hand. 



688 a 

Tojv Or^Xeicbv 7TapaK<EXpf]Tai /cat Trpos erepov epyov 

Tj (jyVGLS, 07T€p ^afiev aVT7]V TToXXoLKLS TTOLelv 0.770- 

25 TLuerai yap ivravOa rols yevvajpiivois Tpo(f)rjv. Svo 
o eiGLv OL {jLauTol 8ta to Svo ra pLopia elvac, to t 
apLOT€p6v /cat TO he^iov. /cat oKXrjpoTepoi /xeV, 
oicopLGiJievoi he Sia to /cat Ta? rrXevpas ovvdiTTeadaL 
fxev dAAy^Aats"^ /caTcx tov tottov tovtov, jxr] eTTiTrovov 
8' eti^at TTjv (jyvGLV avToJv. tols S' d'AAot? t^ojois eV 

so jLtev TO) GTiqdei /.leTa^i) tcov GKeXcbv ahiJvaTov cgtiv 
cp^etv ri ^^aXcTTov^ tovs fiaoTovs (ifXTTohl^oLev (jlcv 
yap av Trpos ttjv TTopelav), €)(Ovgl S' rjSrj ttoXXovs 
TpOTTOVs.^ TO. [xev yap oAtyoTO/ca /cat fJLCJVVXCi Kal 
K€paTocf)6pa eV Tots' piripois exovGC tovs jxaoTovs, 
/cat TOUTOVS" hvo, Ta Se TToXvTOKa r^ TToXvoxt-hrj to. 

35 jLtev Trepl ttjv yaoTepa nXayiovs Kal ttoXXovs, olov 

688 b yg Kal KViOV, TCt Se hvo IXOVOVS, TT€pl fxeGTiv flivTOL 

yaoTcpa, otov Xeojv. tovtov 8* atVtov ovx otl 
oXiyoTOKOv, inel Tt/CTet ttotc TrAetoj 8uotv, dAA' otl 
ov TToXvydXaKTOV dvaXiGKei yap els to GCJjJia T7)r 
XapL^avofJievrjv Tpo(^rjV, Xafi^dvet Se GTrdviov hid to 
5 GapKO(f)dyov elvai. 

*0 8* eXe(j)as hvo piovov e;)^€t, tovtovs 8* vtto Tat? 
piaGxdXais rcov epLTrpoGdiajv GKeXojv. aiTiov he tov 


pLTjpoLS OTL TToXvGXf'hes {ovhev yap ex€L TToXvGxi'hes 
eV TOts piripols), dvoj he Trpos rat? p^aGxdXais, 

^ dAA'^Aas Bekker per typothetae errorem. 
- r) xaAeTTOv P : vulg. non habet. 
^ fort. Tovovs Rackham (sic etiam E teste Buss, et Z), 


the female, Nature employs them for an additional 
function (a regular practice of hers, as I maintain), 
by storing away in them nourishment for the off- 
spring. There are two mammae because the body 
has two parts, the right and the left. The fact that 
they are somewhat hard and at the same time two in 
number is accounted for by the ribs being joined to- 
gether at this place and by the nature of the mammae 
not being at all burdensome. In other animals it is 
either impossible or difficult for the mammae to be 
situated upon the breast, i.e. in between the legs, 
since they would be a hindrance to walking ; but, ex- 
cluding that particular position, there are numerous 
ways in which they are placed. Animals which have 
small litters, both those that have solid hoofs and those 
that carry horns, have their mammae by the thighs ; 
and there are two of them. Animals that have large 
litters or are polydactylous, either have numerous 
mammae placed at the sides upon the abdomen — 
e.g. s\\ine and dogs ; or have only two, set in the middle 
of the abdomen — e.g. the lion.« The reason for this is 
not that the lion has few cubs at a birth, because 
sometimes the number exceeds two, but that it is 
deficient in milk. It uses up all the food it gets upon 
the upkeep of the body, and as it is a flesh-eater it 
gets food but rarely. 

The elephant has only two mammae (this is because 
it has its young one at a time), and they are under the 
axillae of the forelegs and not by the thighs because 
the elephant is polydactylous and no polydactylous 
animal has them there. They are high up, near the 
axillae, because that is the place of the foremost 

** This, like many of Aristotle's statements about the lion, 
is incorrect. 

N 379 


688 b ^ 


jiaGTovg, Kal tjLttuvrat ydXa ttXclgtov. arjiielov 
Se TO Irrl roJv vcov GVjjL^aLVOv rots yap TrpcoroL? 
yevofJiivoLS tojv ^OLpcov rovs rrpcorovs Trapexovui 
/xacrrous" 4^ ovv to npcoTov ywofievov ev fiovov 


rrpJjTOVS' TTpcoTOi 8' €LGLV ol VTTO Tat? pLaGX^Xais . 

15 o p-kv OVV eXi^as hid TavTiqv ttjv atrtav Svo e^^i 
Kal ev TOVTO) tco tottco, Ta 8e TToXvTOKa Trepl ttjv 
yaGTepa. tovtov S' atrtov ort TrXeiovwv Sel jLta- 
GTCJV Tols TrXeioj peXXovGiv e/crpe^etv eirei ovv eVt 
TrXdTOs ovx oTov re aAA' tj Svo p^ovovg ^x^i'V Sid to 
Svo efvat TO t' dpiGTepov Kal to he^Lov, lirl p.r\KOs 

20 dvayKalov ex^iv 6 Se /xeTa^u tottos tcov ep^rrpoGdev 
GKeXdjv Kal TCOV OTTLGOev €X€L p.rJKO? p.6vov. TO, 
8e jJLT) TToXvGxt'hr] aAA' oXtyoTOKa rj KepaTO^opa iv^ 

TOtS" p.r]pOL? eX^L TOV? /XaCTTOU?, olov 177770?, OVO? , 

Kdp.'qXos (TauTa ydp pLOVOTOKa, Kal to, pL€V pLCJvvxa, 
25 TO Se Slxi^Xov), €tl S' eXacf)o? Kal jSou? Kal at^ Kal 
TciAAa TTavTa to. TOiavTa. a'lTiov 8' otl tovtois 
7) av^r]Gi£ errl to aVo) tou GcopLaTos €.gtlv. wgB^ 
OTTOV GvXXoyrj Kal TrepLovGia yiveTai tov irepiT- 
TcopiaTos Kal alpaTOs [ovtos 8' o tottos €gtIv 6 

KdTCJ Kal 7T€pl TCt? €Kpods), ivTavOa iTTOiTJGeV rj 

80 Tpo(f)rjs, evT€vBev Kal Xa^eZv Igtlv avTols hvvaTov. 
dvdptOTTOS piev ovv Kal 6 d-qXv? Kal 6 dpprjv e;^et 
pLaGTOvg, iv Se Tot? d'AAot? eVia tcov dppevojv ovk 
e;^et, ofoy 1777701 ol puev ovk exovGcv ol 8' exovGLV, 


^ Kal €v vulg. : Kal del. Ogle. 


mammae in those that have many, and these are the 
ones that yield the most milk. An illustration of 
this is the case of the sow : a sow will offer the 
first of its mammae to the first ones of the litter. 
Thus, where the first of an animal's litter amounts 
to one and no more, such an animal must possess 
these first mammae, and " the first mammae " means 
those under the axillae. This explains, then, the 
number and position of the elephant's mammae. 
The animals that have large litters have their mammae 
upon the abdomen. Why is this ? They have 
numerous young to feed, and so they need numerous 
mammae. Now as the body has two sides, right and 
left, the mammae cannot be more than two deep 
across the body, and so they have to be disposed 
lengthwise, and the only place where there is suffi- 
cient length for this is between the front and hind 
legs. Non-polydactylous animals which yet produce 
few at a birth, or carry horns, have their mammae by 
the thighs, as the horse and the ass (both solid- 
hoofed) and the camel (cloven-hoofed), all of which 
bear their young singly ; also the deer, the ox, the 
goat, and all such animals. The reason for which is, 
that in them the growth of the body proceeds in an 
upward direction ; so the place where the superfluous 
residue and blood collects is down below, near the 
places of efflux, and there Nature has made the 
mammae ; for where the food is set in motion, there 
is the very place where they can get it. In man, both 
male and female have mammae, but some males of 
other animals have none, as e.g. stallions, some of 
which have none, while others, which resemble their 
dams, have them. 



688 b ^ ^ ^ „ ^ S ^ > -/3 

Kat 776/31 fjLev jjLaarojv eip-qrai, /xera be ro (Tr7]Uos 

35 o Trept TT^v KoiXlav iari tottos, aavyKXeioros rals 

689 a TrXevpals 8ta t')]^ €Lp'qfi€i'r]v efiTTpoaOev alriav, 

OTTOjg fJLT] eix7Tohit,cx)oi fx-qre rr]v olvolStjglv rrj? 
Tpo(f)r]?, rjv dvayKOiov GVfil^atveiv Oepp.aivoiilv'r]'^ 
avrrjs, P-rj^e ra? varepag to,? Trepl rrjv Kv-qoiv. 
TeAo? Se rod KoXovpulvov dcopaKos euri ret pLopua 

6 TO, Trepl Tr]V rrj? TrepiTTOJuecos e^oSov, rrj? re ^r^pas 
/cat TT^S" vypds- KaTa)(prjTaL o tj (f)VGLS rep a'urcp 
piopicp e-ni re rrjv rrjs vypdg e^oSov TTepirrojaeo)^ 
Koi Trepl rrjv 6-)(eiaVy opioiojs ev re rots' drjXeciL kol 
rot? appeoiv,^ e^oj tlvojv oXiyojv Tracrt rots' eVatjLtots", 
iv 8e rot? t^cporoKois TrduLV. a'iriov 8' ort r^ yovrj 

10 vypov eoTL rt Kal TTepirrcnpia. {tovto Se vvv pLev 
VTTOKeiadoj, varepov Se hei\dr]GeTai rrepl avrov.) 
Tov avTOV Se rpoTTov kol ev rots Q-qXeoi rd re 
Karafirivia, Kal fj tt potevr ai rr^v yovijv^' SioptoOij- 
oeraL he Kal nepl tovtojv varepov, vvv 8' vrroKei- 
gOco povov on rrepLrrajpLa Kal rd Karapti^via rolg 

I'j driXeoLV vypd Se rrjV (J)Vglv rd Karafi-qvia Kal tj 
yovi], a)Gre^ rwv opolojv els rd aura* /xopta r7]v 
eKKpiGiv etvai Kard Aoyov eGriv. evrds 8e ttcjs 
ex^i, Kal TTTJ hia(f)epovGL rd re Trepl rd Grreppia Kal 
rd Trepl rrjv kvt^glv, e/c re ri^g iGropias rrjs Trepl 
rd ^cpa (f)avep6v Kal rcJov dvaroptajv, Kal vorepov 

20 XexOrJGerai ev rols Trepl yeveGecog. on 8' e;Y^t Kal 

- Kal €L TTpotevrai nva yom^i' Plait. 

' post (Lore vulfz;. habrt tcDv avTa>v Kal : Ogle del. 

* TO. avTO. Peck : Tavra to. Vlllg. 



This concludes our remarks on the mammae. 

After the breast comes the region around the 
stomach, which is not enclosed by the ribs for 
the reason stated earlier,** viz. to avoid interference 
(a) with the food when it swells, as it must do when 
it is heated, and (6) with the womb during pregnancy. 

At the end of what is called the trunk are the parts Excretory 
that have to do with the discharge of the residue, °^^^^^- 
both solid and fluid. Nature employs one and the 
same part for the discharge of the fluid residue and 
for copulation in all blooded animals (v/ith a few 
exceptions), male and female alike, and in all Vivipara 
without exception. The reason is that the semen is a 
fluid, and a residue. (This statement may stand for 
the present : the proof of it will be given later on.^) 
The same applies to the catamenia in females, and 
the part where they emit the semen.'' This also will be 
dealt with particularly later on. For the present, let 
the statement stand simply that the catamenia in 
females (like the semen in males) are a residue. Now 
both semen and catamenia are fluids, so it is reason- 
able that things which are alike should be discharged 
through the same parts. A clear account of the 
internal structure of these parts, showing the differ- 
ences between the parts connected with semen and 
those connected with conception, is given in the 
Researches upon Animals ^ and the Dissections, and 
there will be a discussion of them in the book on 

* In De gen. an. 724 b 21 ff. 

" This seems to agree with what Aristotle says on the 
subject in the Hist. An., but contradicts what he says in De 
gen. an. Piatt's suggested emendation would make the 
translation read : " and to the semen, if so be they emit any." 

" At 493 a 24-b 6, 497 a 24 ff., book iii, ch. 1. 



689a ^ , ^ , / , ^ , / 

TO, ox^iiara rcbv yLopicav tovtojv rrpos rrjv epyaoiav 

avayKaiojs, ovk dSr^Xov. €;;^et Se Stac/iopa? to rcov 

dppevcov opyavov Kara ras rod Gcofjuarog Sta^opa?. 

ov yap oixoiojs ajTavra vevpcoSr] ttjv (f)VOLV eoriv, 

€Tt 8e fiovov rovro rcuv [jLoplcov avev vooepds /xera- 

26 ^oXrjs av^TjGLv e;^et /cat TaTreivcooiv rovrcov yap to 
jLtev -^piqoLpiOV Trpos tov Gvvhvaopiov, to Se Trpo? tt^v 
Tou aAAou Ga>ixaros ;\;/3etav aet yap opLoicos ^'x°^ 
TttAAa^ eVeTToStJev dV. GVvearrjKe 8e t')7v (j)voiv 
€.K roiovrcov ro fiopLov rovro ware Suvao^at ravr 
dfKJjorepa GVix^alvetv ro /xev yap €X€L vevpcohes 

30 TO 8e ;!^ot'SpaiSes', hcorrep ovvUvai re hvvarat /cat 
eKraoLV e;^etv /cat TTvevfxaros ian heKriKov. rd 
/xev ovv d-qXea rcov rerpaTTohojv Trdvr^ eunv oiri- 
aOovprjrLKd Std ro rrpos rrjv 6-)^eiav ovrcos etrat 
auTOt? ^(prjGifir^v rrjv deoLV, rcov 8* dppevojv oXtya 
eGrlv oTTLGdovpTjrLKa, olov Xvy^, Xecov, /ca/xr^Ao?, 
689 b 8ao-u770u?' iX(x)VV)(OV 8' ouScV €Griv oTTiGSovpririKov. 
To. 8' oTTLGOev /cat TO, 77€pt TO, gkIXtj rols dvdpco- 
7T0LS lSlojs e;^et Trpos" rd rerpdiToSa. KepKov 8' e;)^et 
iravra a^^ehov, ov fxovov rd i^woroKa dXXd /cat to. 
woTOKa- /cat ydp dv fir] fxeyeOos avrols €xov Tvxif 
6 rovro rd fiopiov, dXXd Grjixelov^ y eVe/cev e^pvGi 
riva GroXov. 6 8' dvOpcoTTO? aKepKov fxev eGriv, 
lG)(La 8' e;(et, rdJv 8e rerparroScov ovhlv. en he /cat 
TO GKeXr] 6 fJiev dvOpcxJiros GapKcoSi] /cat p.rjpov'^ /cat 
KV'qixaSy*' rd 8' d'AAa iravr dWp/ca €;)^et, ou jjlovov rd 
^cporoKa dXX* oXojg ooa GKeXrj e\'et ra>v t^wwv 

10 vevpcoSr] ydp e;)(et K'at OGrwSrj /cat dKavdojSrj. 
Tovrojv 8' atVta /xta Tt? eoTtv co? elTreZv diravrajv, 

^ exov TciXXa Peck : exovra vulg. 
2 Tuxs Kackhaiii : ^ vulg. 


Generation.'^ Still, it is clear that the actual forms of 
these parts is determined of necessity by the function 
they have to perform. The male organ, however, 
exhibits differences corresponding to those of the 
body as a whole, for some animals are more sinewy, 
some less. Further, this organ is the only one which 
increases and subsides apart from any change due 
to disease. Its increasing in size is useful for copula- 
tion, its contraction for the employment of the rest 
of the body, since it would be a nuisance to the 
other parts if it were always extended. And so it 
is composed of substances which make both con- 
ditions possible : it contains both sinew and cartilage ; 
and so it can contract and expand and admits air 
into itself. All female quadrupeds discharge the 
urine backwards, as this arrangement is useful to 
them for copulation. A few males do this (among 
them are the lynx, the lion, the camel, and the 
hare), but no solid-hoofed animal does so. 

The rear parts and the parts around the legs are Rear parta. 
peculiar in man compared with the quadrupeds, nearly 
all of which (Ovipara as well as Vivipara) have a tail, 
which even if it is not of any great size, still is present 
for a token as a sort of stump. Man has no tail, but 
he has buttocks, which no quadruped possesses.^ In 
man, the legs, both in thighs and calves, are fleshy : 
in all other animals that have them (not only Vivi- 
para) the legs are fleshless, being sinewy, bony and 
spinous. One might say that there is a single ex- 
planation which covers them all, which is, that man is 

« At 716 a 2—721 a 29. 

'' There seems to be something wrong with this statement, 
but perhaps when taken in conjunction with the whole of the 
argument which follows, it may appear less unjustifiable. 

ofiiKpov vulg. * KVT^fias] TTobas Y. 



689 b 

Slotl fjiovov iuTLv opdov rtxiv t,a)(jjv dvOpcoiTos. tv* 
ovv <f>^P'[} paSicos rdvco Kov(f)a ovra, d^eXovaa to 
GOJfiaTOjSeg dno rcov dvoj rrpos ra Kara) to ^dpog 
rj (j)VULS TrpooedriKev' S Loire p rd LGXiOL aapKwh'q 

15 iTTOLTjae Kal fjLr]pou? kclI yaGTpoKvrjfilag. a/xa he 
T-qv re rcov Ig-x^lojv (f)VGLV Kal irpos ra? dvairavGeLs 
direScjJKe xp^jf^^f^ov rols picv ydp rerpdiroGiv dKOirov 
TO eGrdvai, kol ov KajJivovGi rovro TToiovvra gvv- 
€xdJ9 {a)G7T6p ydp KaraKeipieva hiareXeZ vtto- 
Keipievcov Terrdpcxjv epeiGpaTcov), toI? 8' dvOpcjirois 

20 ov pdhiov opdojs eGr(x)GL hiapLeveiv y aAAa heZrai to 
crcajLta dvaTra-UGecDS kol KadeSpag. 6 /xev ovv dv- 
dpojTTOS LGxicL T ex^t Kal rd GKeXr) GapKCx)Sr} Sta 
TTjV elprjp.ev'qv alriav, Kal hid ravra dKepKov [tj 
re ydp eKecGe^ rpocjir] TTopevofievrj et? ravra dva- 
XiGKerai, Kal Sid ro e;>^etv to-;^ta d(f>'^pr]rai rj rrjs 

25 ovpds dvayKaia XPV^^^)> '''^ ^^ rerpdnoha Kal 
TaAAa ^oja e^ evavrlag- vavcoSeGL ydp ovgl TTpos ro 
dvoj ro pdpog Kal ro Gojjiarcbhes eVt/cetTat Trdv, 
d(j)r]prjp.evov drro rojv Kdrcodev SioTrep dvLGX^o^ f<al 
GKXrjpd rd GKeXrj exovGiv. OTrajg S' iv (f)vXaK7J Kal 
GKeTTTj fj ro Xeirovpyovv pLopiov rrjv e^ohov rod 

30 TrepLrrdjjJLaros, rrjv KaXovpevr^v ovpdv Kal KepKov 
avrolg aTrehcoKev rj <J)Vgls, dcf^eXojJLevrj rrjg els rd 
GKeXrj yiyvopievrjs rpocf)rjg. 

('0 Se TTiOrjKos hid ro rrjv popcfyrjv inajJicfyorepL^eLV 

Kal jxrjherepcov r elvai Kal dpL(f)orepojv , Sta tout' 

out' ovpdv e;\;et ovr lgx^ol, (Lg fiev Slttovs d)V ovpdv, 

CO? 8e rerpaTTOVs lgx^cl.) 

690 a Td)v 8e KaXovjievcov KepKcov hia^opai r et'at 

^ eVeiae Peck : eVei vulg. 


the only animal that stands upright. Hence, Nature, 
so as to make the upper parts light and easy to carry, 
took off the corporeal matter from the top and trans- 
ferred the weight down below ; and that is how she 
came to make the buttocks and the thighs and the 
calves of the legs fleshy. At the same time, in 
making the buttocks fleshy, Nature made them useful 
for resting the body. Quadrupeds find it no trouble 
to remain standing, and do not get tired if they 
remain continually on their feet — the time is as good 
as spent lying down, because they have four supports 
underneath them. But human beings cannot remain 
standing upright continually with ease ; the body 
needs rest ; it must be seated. That, then, is why 
man has buttocks and fleshy legs, and for the same 
reason he has no tail : the nourishment gets used up 
for the benefit of the buttocks and legs before it can 
get as far as the place for the tail. Besides, the 
possession of buttocks takes away the need and 
necessity of a tail. But in quadrupeds and other 
animals it is the opposite : they are dwarf-like, which 
means that their heavy corporeal substance is in the 
upper part of them and does not come into the lower 
parts ; and as a result they have no buttocks and their 
legs are hard. Yet to ensure that the part which 
serves them for the discharge of the residue shall be 
guarded and covered over, Nature has assigned to 
them tails or scuts by taking off somewhat of the 
nourishment which would otherwise go into the legs. 

(The Ape is, in form, intermediate between the 
two, man and quadruped, and belongs to neither, or 
to both, and consequently he has no tail, qua biped, 
and no buttocks, qua quadruped.) 

There are numerous differences in the various tails, 

n2 387 


690 a ^ 

TrXeiovs kol r) <j)VOi£ TrapaKaTa)(prJTaL Kal inl rov- 

Tixiv, ov fiovov TTpos cf>vXaKr]v Kal GKeTrrjv ttjs eSpas, 
dXXa Kal TTpos dj(j)e\eLav Kal )(prioiv rols exovcrtv. 
5 Ot Se TToSe? rots' jJ-€V rerparrooi StacfiepovoLV' ra 
fxev yap p.a)VV)(a avrcov iaru ra 8e St^T^Aa to, 8e 
TToXvaxi'^'^ , picovvxcL /xev oool<; Sta fJLeyedos Kal to 
TToXv yettjSes" ep^etv dvrl Kepdrajv Kal oSovtcdv et? 
Trjv rod ovv^os cf)VGLV to tolovtov pLopiov eXa^ev 
aTTOKpiGiv , Kal hid TrXrjdog dvrt TrXeiovojv ovvx^j^^ 
10 6LS ovv^ Tj ottXtj eoTiv. Kal doTpdyaXov Se Sta 


GKeXovs dGTpaydXov evovTOS' BaTTOV ydp dvotyeTau 
Kal AcAeterat ra piiav exovTa yajvlav tj TrXeiovs, 6 
8' doTpdyaXos yopicfios cciv ojoTi^p dAAorptov kGjXov 

15 ipLpe^XrjTai tols bvGL, ^dpos /xev Trapexov, ttoiovv 
8' dG(j)aXeGT€pav ttjv ^aGLV. Sid ydp tovto Kal iv 
ToZs epiTTpoGdiois OVK ^xovGLV aGTpdyaXov Td exovTa 
aGTpdyaXov, dXX ev rot? oTTiGdev, otl hel iXacf)pd 
elvai Td -qyovfjieva Kal evKafXTTTa, to 8' dcr^aAes' Kal 
TTjv TaGiv iv rots' oiriGOev. €tl Se irpos to d/ivve- 

20 Gdai ijjL^pLOeGTepav 7tol€l ttjv nX'qyrjV' Td 8e rotaura 

rots' OTTiodev ;^p7'5rat K'tuAots", Aa^rt^oyra to Xvttovv. 

Td 8e Slx'^Xa e^et dar/odyaAov {Kov^oTepa ydp 

Td OTTLGdev), Kal hid to ^x^i'V doTpdyaXov Kal ov 

^ Kal 8td S\JZ Ogle : Slol vulg. 

" The word used in the Greek is " part." See Introd. p. 28. 

* See Introduction, pp. 38-39. 


which provide another example of Nature's habit of 
using an organ for secondary purposes, for she 
employs the tail not only as a guard and covering for 
the fundament but also in other serviceable ways. 

There are differences too in the feet of quadrupeds. Hoofs, etc 
Some have a solid hoof, some a cloven hoof ; others 
have a foot that is divided into several parts. Solid 
hoofs are present in those animals which are large 
and contain much earthy substance,*^ which instead of 
making horns and teeth forms an abscession^ so as 
to produce nail, and owing to the abundance of it, it 
produces not several separate nails but a single one, 
in other words, a hoof. Because of this, these 
animals in general have no hucklebone ; and also 
because the presence of a hucklebone makes it 
rather difficult to bend the hind leg freely, since a 
limb that has one angle can be bent to and fro more 
quickly than one that has several. It is a sort of 
connecting-rod, and therefore practically interpolates 
another bit of a limb between the two, thereby in- 
creasing the weight ; but it makes the animal's footing 
more reliable. This explains why, when hucklebones 
are present, they are present in the hind limbs 
only, never in the front : the front limbs have to be 
light and flexible because they go first, while the 
hind limbs must be reliable and able to stretch. 
Further, a hucklebone puts more force into a blow — a 
useful point in self-defence — and animals which have 
one use their hind limbs in this way : if anything 
hurts them they kick out at it. 

Cloven-hoofed animals have a hucklebone, as their 
hind limbs are on the light side ; and that is the very 
reason why they are cloven-hoofed : the bony sub- 
stance stays in the joint and therefore is deficient in 



690 a 

77080? iv rfj KajjufjeL fievov. ra Se TToXvSaKTvXa 

25 ovK €-)(€i aorpdyaXov ov yap av rjv TroXuSaKrvXa, 
dXXa TOGOVTOV i(j-)(Ll,€TO TO TrXoLTOS 600V iTTeyei 
6 doTpdyaXos. Sio koX tG)v lyovTOJV avrov ra 
TrXeiuj Slx'^Xa. 

*0 8' di'OpcoTTog 77oSa? pieyiarovs e;^et tojv t^cpojv 
cog Kara pLeyeOos, evXoyojs' pLovov yap €GTr]K€v 
opdov, ix)GT€ Tov? jLteAAovTas" Su' ovrag e^eiv rrdv to 

30 Tov ocofiaros ^dpos Set pLrJKO? ex^iv /cat rrXdros. 
Kal TO rcov SaKTvXojv Srj pLeyedog ivavrloj? e;^et e77t 
T€ ToJv TToSojv Kal T(x)v x^Lpcov Kara Xoyov rojv 
piev yap to Xapu^dveiv epyov Kal Trtefetv, cooTe Set 
690 b puaKpovs ex^i'V {ro) yap KapLTrropLevco jLtcpet nepL- 
XapL^dv€L rj X^^P)y '^^^ ^^ '^^ ^e^r^Kevai dacf)aX(jo?, 
Trpos 8e^ rovTO 8et to pLopiov elvau pL€lt,ov^ to 
d.Gxi'CrTOv TOV TToSos TcDv SaKTvXojv. eox^^^^^ ^^ 
^cXtlov 7) daxiCFTov elvai to eoxcLTOV aTrav yap av 
5 GVpLTTadeg rjv evos pLopLOV rrovqaavTOS , eCT;YiCTjLteVa>^ 
8' els SaKTvXovg tovt ov uvii^aivei opioicxjs- €tl 
8e Kal ^pax€LS 6vt€s yJttov {av) ^XdrrToiVTO .^ 8to 
77oAuo';^t8ets" ol Trohes tojv dvdpcoTTOJV, ov pLaKpo- 
SdKTvXoL 8' eiGLv. TO Se TOJV ovvxcov yivos Sta 
T9]v avTTjv alriav Kal €ttI twv jj^etpcDy exovaiv 8et 

10 yap GKeTTeaOaL tol dKpwrrjpLa pidXcGra Sid ttjv 


Kal 7T€^djv e'iprjTaL gx^Sov vepl rrdvTOJV XI. tojv 
8* ivalpLOJV ^cpojv OJOTOKOJV 8e to. piev Igtl TeTpd- 

^ TTpos hk Og-le : coCTTC vulg. 

* /xet^ov Piatt, Th. : vo/xll^eiv vulg. 

' caxiofj-cuu) Peek : -ov PY : -cov vulg. : -ov Ogle. 

* <ai> Piatt, Th. : ^Xoltttolvto Y : au/ijSAaTrroiVTO vulg. 


the foot. The polydactylous animals have no huckle- 
bone, otherwise they would not be polydactylous, 
and the divisions of the foot would cover only so 
much width as the hucklebone itself. So most of 
the animals which have a hucklebone are cloven- 

Man of all the animals has the largest feet for his 
size, and reasonably so, since he is the only one of 
them that stands upright, and as the feet have to bear 
the whole weight of the body and there are only 
two of them, they must be both long and broad. 
Also the toes are short compared with the fingers, 
and this too is reasonable. The business of the hands 
is to take hold and to keep hold of things, and this is 
done by means of that part of the hands which bends ; 
therefore the fingers must be long. The business of 
the feet is to get a firm and reliable footing ; and to 
secure this the undivided part of the foot must be 
greater than the toes. And it is better to have the 
tip of the foot divided than not, for otherwise, if one 
part were affected the whole foot would suffer as well, 
whereas this is to some degree avoided by the divi- 
sion of the tip of the foot into toes. Again, short 
toes are less liable to injury than long ones would be. 
All this indicates why the human foot has toes and 
why they are short. There are nails on the toes for 
the same reason that there are nails on the fingers : 
the extremities have but little strength and there- 
fore specially need to be protected. 

We have now dealt with practically all the blooded 
animals that are viviparous and live on the land. 

XI. We now pass on to another class of blooded co Ovipara : 
animals, the oviparous, some of which have four feet, OO^^erpents 

QQj quadrupeds. 


690 b 

TToSa ra S' aTroSa. roiovrov 8' ev [xovov yivos 

15 €gtIv aTTovv, TO Tcov 6^€cov Tj 8' tttTta tt)? aTTohias 

avTcov eip-qrai iv rols nepl rrjg TTopelag tcov t,(jjcx)v 

SLcopLGfxevoLg. TO. 8' d'AAa TrapaTrXrjGLav e;(et Tr]v 

[J.Op(f)rjV Tols T€T pdlTOGl KOI (hoTOKOlS .^ 

*'E;(£t 8e TO. ^a>a raura K€(f)aXrjV pLev /cat ra ev 

auTT^ pLopua Sea ra? ai^ras" atrta? rots' aAAot? rots' 

20 ivaipiOLS t,(I)OLs, koI yXtoTTav iv tco GTop-aTL ttXtjv 


e;\;eiv, aAAa ttjv x<^p(^^ pLovov. atrtov 8' ort TpoTTOv 
pL€v TLva dpia -x^epuaZos kol evvhpos ioTLV 8ta pL€V 
ovv TO ■x^epoalos elvai ex€L ;\;a>pay yXcoTTt]?, 8ta 8e 
TO evvSpos dyXcoTTOs . ol yap IxOve?, Kaddnep €Lpr]- 

25 rat TTpoTepov, ol puev ov Sokovglv e;^etv, a;^ piTj o(j)6- 
hpa dvaKXivrj rt?, ot 8' dSidpOpcoTov exovaiv. aiTiov 
8' ort oXiyq tovtols XP^^^^ "^V^ yXwTTTjs 8ta to pLT) 
ivSex^dOat pLaodudai pLrjhe Trpoyeveodai, dXX iv ttj 
KaTaTToaei yiveodai ttjv atad'qaLV Kal ttjv tjSovtjv 
TTauL tovtols TTJs Tpo(f)rjg. 7} piiv yap yXcoTTa tCjv 

80 x^H'd)v 7TOL€L TTjv aiodiqoiv , Twv he iSeGTcijv iv Tjj 
Kadohcp Tj TjSovq' KaTaTnvopLevcov yap atV^avovrat 
Tojv XiTrapdjv /cat deppLCJov /cat tojv dXXojv tojv 
TOLOVTOJV. ex^i pL€v OVV Kal ra ^cooro/ca TavTrjv 
TTJV aLGdrjGLv (/cat Gx^hdv tcov ttXclgtcov oipcov /cat 

691 a e8eCTrajv iv ttj /caraTroaet ttj raaet tov OLGO(f)dyov 

ytverat 7] ;)^apts" 8t6 ovx ot avTol rrepl ra nopiaTa 
/cat Tovs x^P-ovg aKpaTels €lgi /cat ra oipa /cat Trjv 

^ <1)Ot6kOLS PUYZ : ^WOTOKOIS vulg. 

2 ^v Totirois XPf'a S : -^v XP^'c tovtois vulg. : ^v delevi. 

* At De inc. an. 708 a 9 ff ; see also infra, 696 a 10. 
^ At 660 b 13-25. 


and some no feet at all. Actually there is only one 
group that has no feet, the Serpents ; and the reason 
why they have none has been stated in my treatise on 
the Locomotion of Animals.'^ In other respects their 
conformation is similar to that of the oviparous 

These animals have a head, and the parts that com- 
pose it, for the same reasons that other blooded 
creatures have one, and they have a tongue inside the 
mouth — all except the river crocodile, which appar- 
ently has none, but only a space for it ; and the reason 
is that in a way he is both a land-animal and a water- 
animal. In virtue of being a land-animal, he has a 
space for a tongue ; as a water-animal, he is tongue- 
less. This agrees with our previous statement,^ that 
some fishes appear to have no tongue unless you pull 
the mouth very well open, others have one which is 
not distinctly articulated. The reason for this is that 
these creatures have not much need for a tongue 
because they cannot chew their food or even taste 
it before they eat it : they can perceive the pleasant- 
ness of it only while they are swallowing it. This 
is because the perception of juices is effected by the 
tongue ; whereas the pleasantness of solid food is 
perceived while it is passing down the gullet, and 
thus oily food and hot food and the like are per- 
ceived while they are being swallowed. Of course 
the Vivipara as well as these creatures have this 
power of perception (indeed, the enjoyment derived 
from practically all edible dainties takes place while 
they are being swallowed and is due to the distension 
of the oesophagus — which is why intemperate ap- 
petite for edible dainties is not found in the same 
animals as intemperate appetite for drink and juices) ; 


691 a 

iScoSrjv), aAAa rot? /tev d'AAot? fcoot? Kal rj Kara 

5 TTjv yevGiv V7Tdpx€L aLad-qai?, €K€lvol5 8' dvev 
ravrris jjiovyf 7) irepa. rchv he rerpaTToSajv /cat 
cpOTOKCDv ol oavpoi, iiiOTTep Koi oi^ 6(f)€L£, SiKpoav 
cxovGL rrjv yXdjTrav Kal err* aKpov rpixojhr] TrdfXTraVf 
Kaddnep e'ip'qr at rrporepov. exovai 8e /cat at </)tD/cat 
SiKpoav Tr]v yXcorrav 8to /cat Xlxvcl^ irdvra rd ^oia 
ecrrt ravra. 

10 "Ectti he /cat Kap^o-pohovTa rd rerpdrroha rcov 
tpOTOKOjv, coGTTep ol Ixdves . rd 8' aloQiqr'qpia 
Trdvra opolcos exovai rots' dXXoig ^ojot?, olov rrjg 
6a(f)prjG€ajs fJLVKrrjpas /cat oiJjecDS 6(f)6aXp.ovs /cat 
aKorj? wra, ttXt^v ovk eTraveGTTjKora, KaOdnep ovh* 
ol dpvides, dXXd rov TTopov piovov airiov 8' dp<j)o- 

15 repois rj rov SeppLaros gkXt]p6t7]s' rd pev ydp 
TTTepojrd avrdjv eGn, ravra he rrdvra (j)oXihojrdy 
ecjTt 8* 7] (j)oXls opioiov X^P^ XeTTiSog, cf)VGeL 8e 
aKXrjporepov, SrjXol 8' eirl rwv ;^eAajva;v rovro 
Kal inl rcjv peydXcov 6(f)eojv Kal rcjv TTorapLiOJV 
KpoKoheiXcov LGxvporepai ydp y ivovr ai rwv ocrraJv 
CO? oucrat roiavrai rrjv (f)VGLV. 

20 Ovk exovGL 8e rd ^cpa ravra rrjv dvco j8Ae</)apt8a, 
WGTTep ovh^ ol opvideSy dXXd rfj Kara) pivovGi 8ta 
rrjv air lav rr]v elpr]pevr]v eV eKelva>v. rcov pLev ovv 
opvldcov evioi Kal GKaphapLvrrovGiv vpievi €/c rayv 
Kavddjv, ravra he rd ^a)a ov GKaphapLvrrec gkXtjp- 

25 ocfydaXpLorepa ydp eGn rcov opvldcov. airiov 8' on 
eKelvoLS XPV^'-I^^'^^P'^ V o^vojjrla*^ TrrrjvoLS ovgl rrpog 

^ 8' av€u TavTTjS fiovT) Peck : S' av ij warrep ^ovtj Y : 8' 
wavcpavcl viilg. ; plurima hie transposuit Ogle. 
2 Kal ol Y : ol vulg. 



but whereas the rest of the animals have the power of 
perception b}^ taste as well, these are without it 
and possess the other one only. Among oviparous 
quadrupeds, lizards (and serpents too) have a two- 
forked tongue, the tips of which are as fine as hairs. 
(This has been stated earher.") Seals also have a 
forked tongue. This forked tongue explains why all 
these animals are so dainty in their food. 

The four-footed Ovipara also have sharp interfitting 
teeth, as Fishes have. Their sense-organs are all 
similar to those of other animals : nostrils for smell, 
eyes for sight, and ears for hearing — though their ears 
do not stand out : they are merely a duct, as in 
birds ; and in both groups the cause is the same, viz. 
the hardness of their integument. Birds are covered 
with feathers, and these creatures are all covered 
with horny scales which correspond in position to the 
scales of fishes, but are harder in substance. This 
is clearly illustrated by the tortoises, the great snakes, 
and the river crocodiles, where the scales are made of 
the same material as the bones and actually grow 
stronger than the bones. 

These animals, like birds, have no upper eyelid ; 
they close their eyes with the lower lid. The reason 
which was given ^ for birds applies to them too. Some 
birds can also blink by means of a membrane which 
comes out of the corner of the eye ; but these 
animals do not do this, since their eyes are harder 
than birds' eyes. The reason for this is that keen 
sight is of considerable use to birds in their daily 

«• At 660 b 9. ^ At 657 b 6 ff. 

^ At'xva Karsch : laxva vulg. 

* O^VCOTTLa Kal TO TTOppOJ TTpo'CBe'iv UY. 



691 a ^ ^ ^ ^ 

rov ^lov, TOVTOig S' rJTrov rpajyXoSvra yap iravra 
ra roiavTo. ioriv. 

Et? hvo hk Sirjprjfjievrjs rrjg KecfyaXris, rod re avcxi 
fjLopLov Kal rrjg aiayovos rrjg Karoj, dvdpcxJTTOs jLtev^ 
/cat ra t^cporoKa rcov rerpaTToSajv /cat dvo) /cat Karoj 

80 KLvovGL TO,? oiayovas /cat els to TrXdyiov, ol 8* 
lxdv€s /cat opvideg /cat ra woro/ca rtov rerpaTToSojv 
ets" TO aVoj /cat /caroj fiovov. atrLov S' ort 77 jLtev 
691 b TOiavTT] KLV7]aLs ^^p-quipLOS €L£ TO Sa/cetv /cat SteAetv, 
7^ S' els TO TrActytov eVt to Xealveiv. roTs p-kv ovv 
exovGi yop,(f)LOVS XP'^^^H'OS r) els to irXdyiov Kivqais, 
rols Se pLi] exovGLv ovSev XP'^^^^-OS, hioTvep d(j)r]priTai 
TTavrcov rwv tolovtcov ouSev yap ttolel Trepiepyov rj 
6 (f)VGLS. rd jLtev ovv dXXa Travra KiveZ rrjv Giayova 
TTjv /caret), o 8e TTordpiios KpoKoheiXos fiovos ttjv dvoj. 
TOVTov S' atrtov ort Trpos ro Xa^elv /cat KaraGxelv 
dxp'^fJTOvs ex^i' Tovs TToSas' puKpol yap etVt Trdpurav. 
TTpos ovv ravras rds XP^^^^ ^^^^^ ttoScjv to cxro/xa 
7) (f)VGLS ;\;/37]o-t/xov auroi erroirjGev. Trpos Se to 

10 KaraGx^iV rj Xa^eZvy onorepajdev dv fj rj TrXrjyrj 
iGXvporepa, ravrrj ;)^p7^CTt^ajTepa Kivovpevrj eGriv 
Tj he TrXrjyrj loxvporepa del dvcoOev 7) Kdrcodev eVet 
ovv dp.(j)OTepcov pLev Sia rod oroparos rj XP^^^^> ^^^^ 
Tov Xa^elv /cat rod Sa/cetv, dvayKaiorepa 8' rj rov 

15 KaraGX^Zv pufjre ;^etpas" exovri purjre TTohas ev(j)veZs, 
XP'^GLpidyrepov rrjv dvcoOev Kivelv Giayova rj ttjv 
Karojdev avroZs. 8ta to avTo he /cat ot KapKivoi 
TO dvcoOev rrjs XV^V^ klvovgl popiov, dAA* ov to 
KaTcoOev dvTL x^i-pos yap exovoi rds ^^Aas", coare 
rrpos TO Xa^elv dAA' ov rrpos to hieXelv p^/oi^ct/xov 

* fikv ovv vulg. : yikv YZ. 


life, because they fly about ; but it would be very 
little good to these creatures, because they all spend 
their time in holes and corners. 

Their head has two divisions : the upper part, and 
the lower jaw. In man and in the viviparous 
quadrupeds the lower jaw moves from side to side as 
well as up and down ; in fishes, however, and birds 
and these oviparous quadrupeds it moves up and 
down only. The reason is that this vertical motion is 
useful for biting and cutting up food, while the 
sideways motion is useful for grinding the food down. 
Of course this sideways motion is useful to animals 
which possess grinder-teeth ; but it is of no use to 
those which lack grinders, and so not one of them 
has it. Nature never makes or does anything that is 
superfluous. All these animals, then, move the lower 
jaw — with one exception, the river crocodile, which 
moves the upper jaw, and the reason for this is that 
his feet are no use for seizing and holding things : 
they are too small altogether. So Nature has given 
him a mouth which he can use for these purposes 
instead of his feet. And when it comes to seizing 
things and holding them, the most useful direction 
for a blow to take is that which gives it the greatest 
strength. Now a blow from above is always stronger 
than one from below. And to an animal who has no 
hands and no proper feet, who has to use his mouth 
for seizing his food as well as for biting it, the power 
to seize it is the more necessary ; and therefore it is 
more useful to him to be able to move his upper jaw 
than his lower one. For the same reason crabs move 
the upper part of their claws and not the lower : 
claws are their substitute for hands, so the claws have 
to be useful for seizing things (not for cutting them 

. 397 


691 b ^ ^ 

liu Set etvai rr]v XV^W' '^^ ^^ hieXeZv /cat Sa/cetv ohov- 
TCDV epyov ioriv. roig fxev ouv KapKivois Kal toIs 
aXXoLg oGOig ivSex^rai axoXaiajg rroieZoBai ttjv 
XrjifjLV Slol to fii) eV vypco etvat t7]v ;Yp^crtv rou 
aTOjjLaros, SLrjp-qraL, Kal Xapi^dvovGi {xev ;^epCTtv 7} 
TTOoi, hiaLpovoi Se roi CTTo/xart /cai SctKyofcrtv rots' 

25 Se KpoKoheiXois eir* a/x^orepa xRV^^H-^v ro arofxa 


"E;^ouCTt he Kal au;)^eVa Travra to, roiavra Sta to 
TrXevpLova e;^etv 8e;YovTat yap to TTvevpia Sta t-^? 
apr-qpias fJLrJKog ixovarjg. 

^'ETTet Se TO fxeTa^v K€(f)aXfjs Kal c^fjLOJV KeKXr^Tat 

avx'ij^, TjKiuTa TCx)v TOLOVTCov 6 6(f)Ls So^ctcv dv 

30 ex^iv avx^va, dXXa to dvdXoyov tco avx^vi, et ye 

Set rot? eipry/xeVot? ioxdTois Stopt^etv to fiopiov 

TOVTO. tStov Se 77/309 TCt ovyyevrj tcov t,a)Cx)v 

692 a VTrdpX^l TOt? 6(f)€GL TO OTp€(f>€LV TrjV K€(f)aXrjV et? 


8* OTt Kaddirep to, eVroju-a eAtKTOV' eoTiv, wot€ 
evKdfJLTTTOVs ^X^^^ ^'^^ ;\;ovSp668ets" tou? ctttovSuAous". 
e^ ayay/c'/y? jLtev ouv 8ta TavTr]v ttjv atTtav tovto 

5 GVfji^€^rjK€v avTolg, TOV Se ^eXTiovos eVe/cev tt/jo? 
(f)vXaK7]v tcl)v oTnodev f^XaTTTovTWV fiaKpov yap ov 
Kal aTTovv dcf)ves eVrt 77^0? re tt^v GTpo(l)rjv Kal irpos 
Trjv TCOV oTTiGBev T-qpriGiv' ovhev yap o^eXos atpeiv 
pL€v, GTpe^eiv 8e fxr] SvvaGdai Tr)v K€<^aXrjV. cxovGi 
8e TO, ToiavTa Kal to) GTrjdei avaAoyov pLopiov. 

10 fiaGTovs 8' ovK exovGLV ovT ivTavda ovt iv tco 
dXXo) GcofJiaTi, oixoLOjg 8' oOS' opvLs, ovh^ Ix^vs 
ovheis. atVtov Se to fJtrjSe ydXa ex^cv to-utcjv 

^ hinc usque ad 695 a 22 varia codd. ; text. vulg. exhibui. 


up : this, and biting, is the business of the teeth). 
In crabs, then, and in other creatures which, because 
their mouth does not come into action while under 
water, can take their time about seizing their food, 
the labour is divided : they seize their food with 
their hands or feet, and cut it up and bite it with 
the mouth. For the crocodile, however, by making 
the jaws move as I have described, Nature has 
constructed a mouth which can be used for both 
these purposes. 

All these animals have also a neck ; this is because 
they have a lung and there is a long windpipe through 
Vvhich they admit the breath to it. 

Since the neck is the name given to the part of 
the body between the head and the shoulders, the 
serpent would appear to be the very last of these 
creatures to possess one : at any rate, if the neck is 
to be defined by the limits mentioned above, he has 
merely something analogous to a neck. Compared 
with kindred animals, serpents have this peculiarity : 
they can turn their heads backwards while the rest of 
the body remains still. The reason is that their body 
(like an insect's) can roll up ; the vertebrae are cartila- 
ginous and flexible. This, then, is the necessary cause 
why they have this ability; but it serves a gooc? purpose 
too, for it enables them to guard against attacks from 
the rear, and with their long bodies devoid of feet 
they are ill adapted for turning themselves round to 
keep watch over the rear. To be able to raise the 
head and yet unable to turn it round would be useless. 
These animals have also a part which is a counter- 
part to the breast. But they have no mammae either 
here or elsewhere ; nor have any of the birds or fishes. 
This is because the mammae are receptacles, vessels, 



692 a 

fjir]d€V' 6 Be fiauTO? vttoSox'T] Kal woirep ayyeZov 
icTTL ydXaKTO?. ydXa 8' ovk ex^t ovre ravra ovr* 
dXXo ovSev TOJV fjLrj I^ojotokovvtcov iv avrots, Slotl 
(hoTOKOVGLV, €V §€ Tcp (hcj 7] rpo(l)rj iyyiverai iv 
rot? t^iporoKOis yaXaKTcoSrj? vrrdpxovoa. cra^e- 

15 orrepov 8e Trepl avrojv XexO'qo-erai iv rot? nepl 
yeveaeojs. Trepl he rrj? tcov OKeXcjv^ Kdpujjecos iv 
rols rrepl rropeias Trporepov iTTeaKeTTrai Koivfj Trepl 

"Kxovai Se Kal KepKov rd roLavra, ra fxev /xet^co 
rd S' iXdrrco, VTrep ov rrfv alriav KaOoXov Trporepov 

20 ^luxvoTaros S' o x^H'^^^^^'^ "^^^ cootokojv Kal 
TTe^ojv icTTLV oXiyaipLOTaTov ydp ian Trdvrojv. ravro 
8' atnov rod rrj? ipvx'^s yjdovg iorl rod t,a)ov^ ttoXv- 
{xop(f)ov ydp yiverai hid rov (f)6^ov, 6 he cf)6^og 
Kardifjv^LS St' oXiyaifjiorrjrd ion Kal evheiav depfio- 
692 b He pi pev ovv rdjv ivaipcov t,a)ajv rcov re dTTohojv 
Kal rerpaTTohojv, daa popia rd iKros ex^i Kal hid 
rivas air lag, elp-qrai ox^hov. 

XII. 'Ev 8c rolg dpviGiv T) TTpo? dXXrjXa Sta^opa 
iv rfj rcov popla>v iorlv vTrepoxfj Kal iXXelipet Kal 
5 Kard rd pidXXov Kal rjrrov. elal ydp avrojv ol p,ev 
fxaKpoGKeXels ol he ^paxvoKeXelg, Kal rrjv yXcbrrav 
ol jjiev TrXareZav exovaiv ol he arev^v o/xotcas" he 
Kal eTTt TCOV dXXwv pLopiiov. Ihia he fiopca oXiya 

^ OKeXwv PZ, Ogle : KaiiTTvXojv okcXcou Y : KafjLTTvXcov vulg. 

2 Trepl Se . . . ttolvtcdv fortasse secludenda. 

' correxit Peck, cf. 667 all seqq. ; tovtov S' aiTLou to ^dos 
Tov Ccoov TO T7y? ^vx^js vulg. : axTiov 8e to t^? 4'^XV^ -^Oos €cttiv 
auTou PS UZ : sed fortasse haec verba secludenda. 



as it were, for the milk, and none of these creatures 
has any milk. Neither has any of the other animals 
that are not internally viviparous ; the reason is that 
as they produce eggs the milky nutriment which they 
contain goes into these eggs. A more detailed 
account of these matters \W11 be given in the treatise 
on Generatio7i.^ With regard to the way in which they 
bend their legs, a general account, including all 
animals, has already been given in the treatise on 
the Locomotion of Ariimals.^ 

These creatures have a tail, some a large one, some 
a small one. We have already given the reason for 
this as generally applicable.^ 

Among the oviparous land-animals, the chameleon 
has the least flesh on him ; this is because he has 
least blood, and the same reason is at the root of the 
animal's habit of soul — he is subject to fear (to which 
his many changes in appearance are due), and fear is 
a process of cooling produced through scantiness of 
blood and insufficiency of heat.'^ 

This fairly concludes our account of the external 
parts of the blooded animals both footless and four- 
footed, and of the reasons thereof. 

XII. We now pass on to Birds. As among them- (ii.) Birds. 
selves, they differ in their parts in respect of the 
more and less, and excess and defect^ — e.g., some of 
them have loner leo-s, some short ones ; some have 
a broad tongue, some a narrow one ; and similarly 
with the other parts. Thus, as among themselves 

" At 752 b 16 fF. 

" At 712 a 1 ff. See also below, 693 b 3, and additional 
note on that passage, p. 433. 
<= At 689 b 1 ff. 

^ Compare the passages at 650 b 27 and 667 a 1 1 fF. 
* See 644 a 19, and introductory note on p. 19. 



692 b 

Sta^e/Dovra exovacv dXXrjXcjov irpos he to. ctAAa t,<2)a 

Koi rfj ijLop(f)fj Tcov fjiopiojv Sta^epouatv. Trrepcorol 
10 [jL€v ovv airavTes eloLV, /cat rovr^ Ihiov cxovai rcov 
dXXcxJV. rd yap /xopta rwv ^cpojv rd fiev T/3t;)(ajTa 
ioTL rd Se ^oAtScora to, 8e XemScord, ol 8' dpvides 
TTrepojTOL. /cat to irrepov a)(iGTdv /cat ovx o/jlolov 
rep etSet rot? oXorrrepois' rcov puev ydp du-x^LOTOv 
TCOV 8e (Jxi'CrTov icm, /cat to /xey a/cauAoy, to 8' 
15 e^^et /cauAov. exovac Se /cat ev Try KecfiaXfj TrepLrrrjv 
/cat tStov TT^v Tov pvyxovs (f)V(JLV TTpo? rdXXa' roXs 
fjuev ydp eXecfyaaiv o jjlvkttjp dvrl x^^pd^^> '^^^ ^' 
ivTopLCov evLOLS Tj yXiorra dvrl arofJLarog, ro'urois 
8' dvTt ohovrojv /cat ;!^€tAcur ro p-uyxos oonvov 6v.^ 
7T€pl 8e rdjv aloOiqr'iqpiOJv etprjraL Tvporepov. 
20 Avx^voL 8' e;\;et rerafievov rfj </)i;CTet, /cat 8ta rr^v 
avTTjv air lav rjvTrep /cat TaAAa* /cat rovrov rd fxev 
^paxvv rd 8e piaKpov, /cat o-;^^^^^ d/coAov^ov TOt? 
GKcXeGL rd TrAetCTTa. to, /xev ydp pLaKpoGKeXrj 
IxaKpov Ta 8e ^paxvGKeXrj ^paxvv e;\;et rov avx^va, 
XiJ^pl? TCOV oreyavoTTohcxyv rd piev ydp et etx^ ^P^~ 

693 a x^'^ ^77^ (JKeXeai piaKpols, ovk dv VTrrjperei avroZs 6 

avx'TjV rrpog r7]v ajro rrj? yrjg vopLrjv, roZs 8' el 
jxaKpo? rjv eVt ^paxeoLV. en 8e^ Tot? Kpeco^dyoLS 
avrojv vrrevavriov dv -^v^ ro pcrJKo? TTpos rov ^lov 
5 6 ydp /xa/c/)o? avx^v daOeviqs, rols 8' d ^to? e/c 
Tou Kparelv eariv. hioirep ovhev rcov yapii/jcovvxcov 
IxaKpov ex^i rov aup^eVa. Ta 8e o-Teyai'd77o8a /cat 
^Ta)* hirjpripievovs piev exovra rovs rroSas GecnpLCo- 

^ 6v Y, Ogle : cm. vulg. 


they have few parts which differ from one to another. 
But as compared with other animals, they differ in 
respect of the form of their parts. One pecuHarity 
of the birds is that they all have feathers, whereas 
in other animals the parts are covered with hair, or 
scales, or horny plates. A bird's feather is split, and 
therefore different in form from the wing of certain 
insects, which is undivided ; as well as having a shaft, 
whereas the insects have none. Another peculiarity 
of birds is the beak, an extraordinary appendage to 
the head. It is made of bone, and serves them 
instead of teeth and lips, just as the elephant's trunk 
takes the place of hands, and the tongue of certain 
insects replaces a mouth. We have spoken already 
of the sense-organs.^ 

Birds have a neck which sticks up, and for the same 
reason that other creatures have one. Some have a 
long neck, some a short one : in most of them it corre- 
sponds in length fairly closely to the legs, so that the 
long-legged birds have a long neck and the short- 
legged birds a short neck (web-footed birds excepted.) 
WTiat assistance in getting food out of the ground 
would a short neck be to a bird on long legs, or a long 
neck to a bird on short legs ? Furthermore, the 
carnivorous birds would find a long neck a real dis- 
advantage in their daily life. These birds depend 
for their livelihood on superior strength, and length 
of neck means lack of strength ; so no crook-taloned 
bird has a long neck. Web-footed birds, how- 
ever, together with others in the same class whose 

° In Book II. chh. 12 fF. 

2 Se Langkavel : ye Y6 : om. vu\g. 

^ av ^v PY6, Ogle : om. vulg. 

* <Ta> Ogle. 



693 a 

fji€Vovs Se Kal^ ev tco avraj yevei ovra rot? areyavo- 
TTOGL, rov fikv avx^vo. fjLaKpov €)(ovglv {xpijoifjio? 
ycip TOLOVTO£ a)v TTpos TTjv rpocpT^v rrjv €K rod 

10 vypov), TO, Se GKeXrj rrpog ttjv v€vglv j^pax^a. 

Aia</)opdv S' €X€L Kal ra pvyx'f] Kara rovs ^iovs. 
ra [lev yap evOv e^et ra 8e yapupov, evdv fiev OGa 
rpo(f)rj? €V€K€V, yapupov Se ra chpio^dya- xPV^f-f^ov 
yap npog ro Kparelv ro roLovrov, rrjv Se rpocfir^v 
avayKalov arro ^ctjcov 7Topil,€Gdai, Kal ra ttoXXol 

\'> jSua^ofxevoL?. ogcxjv 8' eXeuos 6 ^los Kal rroo(jidyos, 
irXarv ro pvyxos exovGiv irpog re yap rrjv opv^tv 
XpriGipiov ro roiovrov Kal irpos rr^v rrjs rpO(f>r\s 
GTTaGLV Kal Kovpdv, eVia Se /cat p.aKpov e;^et to 
pvyxos rojv roLovrwv, wGjrep Kal rov au;^eVa, Slol 
ro XafJL^dveLV rrjv rpo(f)r]v €K rov ^dOovs. Kal ra 
TToXXd rcov roiovrcov Kal raJv Gr€yavoTr6Sa>v rj 

20 cxTrAajS" rj Kard^ pLopuov^ drjpevovra l^fj rcjv iv rep 
vypcp cVta ^cpSaplcov Kal yiver at roXg roiovroLS 6 
jxev avx'Tjv Kaddrrep dAteurat? d^ /cdAa^os", ro he 
pvyxos olov rf oppid Kal ro dyKLGrpov. 

Yd Se TTpavrj rod Gcofiaros Kal ra VTrria, Kal ra 
rod KaXovjxevov daypaKos eVt rcov rerpanoScov, 

25 6Xo(f)vrjs 6 r OTTOS errl rcov opvldcov eGriv Kal exovGLV 

aTT'qprrjpLevas dvrl rcov ^paxidvcov Kal rwv GKeXwv 

693 b TcDv TTpoGdicDV^ TO.? TTrepvyas, 'Ihiov n fiopiov, 

hiorrep dvrl cofjLOTrXdrrjs ra reXevrala errl rod vcorov 

rcov nrepvycov exovGLV. 

^KeXt] be Kaddrrep dvOpojiros hvo, KeKafjijieva 

^ Kal Y6, Oprle : (Ls vulg. 
2 Kara Y, Ogle : Kara to vulg. 

^ post fxopiov habct ravTO vulg. : ravTO. S : ravra P : tovtois 
coni. Ogle. 



feet though divided into toes yet are fashioned hke 
a snub-nose" — these have long necks, because a long 
neck is useful to them for getting food out of the 
water. Their feet, on the contrary, are short so that 
they can swim. 

Birds' beaks also differ according to their different 
habits of life. Some beaks are straight, some curved ; 
straight if they are used simply for feeding, curved if 
the bird eats raw meat, because a curved beak is 
useful for overpowering their prey, and such birds 
have to get their food from animals, most often by 
force. Those whose life is spent in swamps and are 
herbivorous have broad beaks, which are useful for 
digging and pulling up their food and for cropping 
plants. Some of them, however, have a long beak and 
a long neck as well, because they get their food from 
some depth. Practically all these birds and the com- 
pletely or partially web-footed ones live by preying 
upon certain of the tiny water-animals, and their 
neck is to these birds what his fishing-rod is to an 
angler, while their beak is like a line and hook. 

The under and the upper sides of the body (i.e. of 
what is called the trunk in quadrupeds) are in birds 
one uninterrupted whole. Instead of arms and fore- 
legs they have wings attached to this part (wings are 
another peculiarity), and hence, instead of having the 
shoulder-blade on their back they have the ends of 
the wings there. 

Birds, like men, have two legs, which are bent in- 

" According to Ogle, this means that the main stem of the 
toe corresponds to the ridge of the nose, and the lobes on 
either side of it to the flattened nostrils. 

* dAteuTat? o PQSU : aXievriKos 6 Y6 : clXuvtikos Z, vulg. 
^ 7) Yb : om. vulg. 

* sic Y6, Ogle : aTrqpr. yap avrl et mox exovai post vpoadLcov 



693 b 

Kaddnep rd TerpdrroSa etaco, /cat ovx cjOTrep dvdpco- 
5 TTos" ^ico' rag Se Trrepvyas, cus" rd TrpoaOia OKeXr] 
rojv rerparrohcjVy irti rd nepLcfiepes. Slttovv S' ef 
dvdyKTjs iariv rwv ydp ivalficov r) rod opvidos 
ovoiay d'/xa Se kol rrrepvycoros, rd S' eyatjua oi) 
Kivelrai TrXetoatv rj rerrapcrt orjixeLOL?. rd p,ev ovv 
d7Tr]pTrjjJL€va jxopia . rlrrapa, (jjarrep rols d'AAot? 
rots' 776 ^ot? KOI rols TTopevrLKoZs, eon kol rots 

10 opviOLV dAAd rot? pikv ^paxioveg /cat gkcXtj, rols 8e 
rerpdrrooL^ GKeXrj rerrapa V7rdp)(^ei, rols S' dpviOLV 
dvrl roL)v TTpoodiojv GKeXcov rj ^paxidvcov Trrepvyes 
TO lBlov ear IV /card ravros ydp rovLKoi^ eloi, rep 
8' opvidi €v rfj ovGia rd TTrrjTLKov eGriv. ojGre 
AetVerat azJrot? e|- dvdyKr\s Slttoglv etvat* ovrco ydp 

15 rerrapGL Gruxeiois KivrjGovrai p^erd rcov nrepvyajv. 

ILrrjOos S' €XovGLV drravres o^v /cat GapKcoSes, 

o^v p,€v rrpds rrjv TTTrJGLV {rd ydp rrXarea ttoXvv 

dipa (hdovvra BvGKLvrjrd eGri), o-ap/ctoSe? 8e, Stdrt 

rd o^v doOeves jjirj ttoXXtjv exov GKerrrjv. 

'IVd Se rd GrijOos KoiXia /xe;^pt Trpdg rrjv e^oSov 

20 rov Trepirrcoparos /cat rrjv roJv GKeXojv KapurriVy 
KadaTTep rols rerpdrroGL /cat rot? dvdpwTTois. jLte- 
ra^u p.ev ovv rcov Trrepvycov /cat rcov GKeXcbv ravra 
rd popid eartr. 

'0/x^aAdv 8' iv jjLev rfj yeveoei dnavra e^et 

^ sic PY6, Ogle : okcXt], toIs hk TCTp. om. vulp;. 
^ TTTTjTiKOL coiiieci ; idem Th. {volatiles Gaza). 

" For an explanation of Aristotle's terminology on this 
subject see additional note on p. 433. 

^ The chief difficulty in translating this passage is due to 
the word tovlkoi, a jargon-adjective in -lkos, which seems to 
have been suggested to Aristotle's mind by the similar adjec- 



wards as in the quadrupeds, not outwards as in man." 
The win_<TS are bent with the convex side outwards, 
like the forelegs of quadrupeds. It is inevitable that 
a bird should have two feet, for (a) it belongs essenti- 
ally to the blooded creatures and (b) it is winged, 
and (c) four is the greatest number of motion- 
points which a blooded creature can have. So there 
are four parts (or limbs) attached to a bird's body, 
and this corresponds exactly with the other blooded 
creatures, viz. those that live and move upon the 
ground. The only difference is that whereas the 
latter have two arms and two legs (or, if they are 
quadrupeds, four legs), the peculiarity of birds is 
that they have wings instead of arms (or forelegs). 
As its very essence includes the power to fly, a 
bird must have something which it can stretch out, 
and wings provide this.^ So it remains that of ne- 
cessity a bird shall have two feet : these with the two 
wings bring up the number of its motion-points 
to four. 

All birds have a sharp-edged, fleshy breast : 
sharp-edged, for flying (a wide surface displaces so 
much air that it impedes its own motion) ; fleshy, 
because a sharp-edged thing is weak unless it has 
a good covering. 

Below the breast is the stomach, which extends (as 
in the quadrupeds and in man) as far as the residual 
vent and the point where the legs join the body. 

Those are the parts, then,w^hich have their situation 
between the wings and the legs. 

Birds, in common with all animals which are pro- 

tive 7tt7)tlk6v in the next line. Literally, the passage reads : 
" for it is at these [viz. the wings] that birds are stretchable ; 
and flight-ability is included in the essence of a bird." 



693 b 

oaaTTep t^cooTOKelrai rj cooro/cetrat, raJv 8' opviBojv 

av^rjOevTCOv dSrjXo?. r) 8* air la StJXtj iv roT? nepl 

25 yeveaLV etV yap to evrepov r) (TVfJL(f)vaLS ylverai, Kal 

ovx cjoTTcp ToZs t^cporoKOLS Tcov </>Ae^cDv Tt fiopLov 


"Ert Tcov opvlOajv ol piev tttt^tlkol Kal rag irrepvyas 

694 a peydXas exovGL Kal laxvpds, olov ol yapn/jcjvvx^S 

Kal d)pLO(f)dyoL- dvdyKrj yap tttt^tlkov?^ etvat Sid rov 
^loVy u)a6^ eVe/ca tovtov Kal TrXrjOog exovoL nrepajv 
Kal rds TTTepvyas pLeydXag. eon 8' ov piovov rd 
5 yapipcuvvxoL dXXd Kal dXXa yevq opviOtov TTTTjTiKd, 
OGOLS r] GixiTi^pia iv rfj raxvrrJTL rrjs 'rmqaeajs r^ 


opviOojv iarlv dXXd papea, oh 6 ^log eVtyeto? Kal 
euTL Kap7TO(f)dya rj rrXcord Kal nepl vhojp ^lorevov- 
OLV. eari 8e rd piev tcov yapufjojvvxojv awpiaTa 
pLLKpd dvev^ TCOV 7TT€pvya)v Sid to els raura?^ dva- 
XioKeudai TTjv Tpocfirjv {/cat)'* etV ra oVAa Kal ttjv 

10 ^o'TjOetav TOLS Se pLrj 7TTr]TiKoZs TovvavTiov ra oco- 
pLaTa oyKcoSr], Sto ^apea iarlv. exovgl 8' cvlol 
rcjv ^apecov ^OT^Oetav dvrl rcov Trrepvycov rd KaXov- 
pL€va^ TrXrJKrpa inl rot? OKiXecnv. a/xa 8' ol avrol 
01) ylvovr at TrXrJKrpa exovres Kal yapuipcovvx^S ' 

15 alnov 8' on ovSev rj (/)vaLS rroieZ rrepUpyov. eon 
8e roZs piiv yajxifjajvuxois Kal TTrrjriKoZs dxprjcrra rd 

^ TTTTjTLKovs P, Rackham : ttttjtlko. Y6 : vttjtlkoIs Z, vulg. 

^ post dvev habent tcov Trrepcov Kal Y6. 

^ €ts ravras QSUZ : ivravda Vulg:. 

* <Kal> Ogle. 5 desinit Z. 

° This passage must lie supplemented by reference to others 
(such as Degen. an. 758 b iiO ff., and Hist. An. 561 b), in which 
Aristotle speaks of txco umbilici or umbilical cords— j..?. he 
recognized the allantois as well as the umbilical vesicle. He 


duced alive or out of eggs, have an umbilicus while 
they are developing, but when they are more fully 
grown it ceases to be visible. The reason for this is 
clear from what happens during their development : 
the umbilical cord grows on to the intestine and 
unites with it, and does not form a part of the system 
of blood-vessels, as it does in the Vivipara." 

The good fliers have big strong wings, e.g. the 
birds which have crooked talons and feed on raw 
meat : these must be good fliers owing to their habits 
of life, and so they have an abundance of feathers and 
big wings. But there are other sorts of birds which are 
good fliers beside these : birds whose safety lies in 
their speed of flight ; and migrants. Some birds are 
poor fliers : heavy birds, which spend their time on 
the ground and feed on fruits ; or birds that live on 
and around the water. The crook-taloned birds, leav- 
ing out of account their wings, have small bodies, be- 
cause the nutriment is used up to produce the wings 
and weapons of offence and defensive armour. The 
poor fliers, on the contrary, have bulky, and therefore 
heavy, bodies. Some of these instead of wings have 
as a means of defence " spurs " on their legs. The 
same bird never possesses both spurs and talons, and 
the reason is that Nature never makes anything that 
is superfluous or needless. Spurs are of no use to a 

.states that in the bird's egg, as the embryo grows, the allantois 
(the " second umbilicus ") collapses first and then the " first 
umbilicus " {De gen. an. 754 a 9). Actually the reverse 
order is the correct one, but the interval is comparatively 
short. The umbilical vesicle in mammals, which shrivels 
very early in the process of development, escaped the notice 
of Aristotle, who supposed their allantois to be comparable to 
the umbilical vesicle of reptiles and birds. The umbilical 
vesicle of mammals was discovered by Needham in 1667. 
(See Ogle's note ad loc.) 



694 a 

nXrJKTpa- xp"^^^!^^ Y^P ecrrtv iv rat? TT-efat? fxdxcLf'?, 
8to vnapx^L evLois rcov ^apecov tovtols 8' ov 
fjLOVOv dxpT^crroL dXXa Kal jSAa^epot ol yafiipol ovvx^S 
to) ejjLTnjyvvadaL VTrevavrloi Trpo? rrjv Trope tav ovres. 

20 hio Kal rd yapujjcovvxo. Trdvra <j>avX(x><s TTopeverai 
Kal €771 TTerpais ov KaOit^dvovdiv VTrevavria yap 
avrols TTpos diJL(J)6r€pa rj tcjv ovvx^iv ^vois. 

'Ef dvdyK7]<^ 8e tovto irepl rr^v yeveaiv av/ji^e^rj- 
K€V. TO yap yccuSe? iv rco crcojaart i^op/JLcopLe- 
vov^ XprjcTLiJia /JLopta yiver at irpo? rrjv dXKijv dvo) 
fiev pvev pvyxovs erroi7]0€ aKX-qpoTT^ra t) fjLeyedo?, 

25 dv 8e Karoj pvfj, TrXrJKTpa iv rot? OKeXeoiv t) eVt 
Tojv TToScov ovvxcov [xiyeOos Kal lax^v. a/xa 8' 
dXXoOi Kal dXXoBi eAcacrra tovtojv ov Trotet' 8ta- 
aTTOJixevr] yap dodevrjs ytVerat 7] (jivais rovrov tov 
TrepLTTCofjiaTOS. tol? 8e GKeXojv KaraoK^vdl^ei firj- 
694 b KOS". ivLois 8' dvrl tovtojv GVfJLirX'qpoZ to /xera^u 
Tcbv 7Toho)V' Kal 8ia tovto dvayKaioj? ol 7rXa>Tol 
T(2)v opvlOcov OL fiev drrXajg elal GTeyavoTToSeg , ol 8e 
SLfip'qfJLevrjv fiev exovGL ttjv Kad^ e/cacrra TCJbv SaKTV- 

5 Xa)V (f)VGLV, TTpos eKdoTCp 8' aVTWV TTpOGTT€(f)VKeV 

olov TrXdTiq Kad^ dXov ovvex'r]S. 

'Ef dvdyKYjs fiev ovv TavTa cru/x/SatVet 8ta raura? 
ras" aWias' a>? 8e 8ta to ^cXtiov ixovoL tolovtovs 
Tovs TToSag tov ^lov x^P^^> ^^^ t,o)VT€s iv vypo) Kal 
tCl)v TTTepvyoiv^ dxpeLa>v ovtojv tovs TTohas XPV^^' 
fjLOVS exojcrt' Trpds ttjv vevaLV. yivovTai yap ojoTrep 

^ i^opixcoixevov Peck : Kal e^opfMOV eV tovtov to. Y6 : e^O) pvev 
Langkavel ; fortasse i^opfi.dTai Kal eV tovtov to.. 
^ TTTcpvycov Y6, Ogle : TiTcpwv vulg. 



bird that has talons and can fly well : spurs are useful 
for fights on the ground, and that is why certain of 
the heavy birds possess them, while talons would not 
be merely useless to them but a real disadvantage ° : 
they would stick in the ground and impede the birds 
when walking. And in fact all crook-taloned birds 
do walk badly, and they never perch upon rocks ; 
in both instances the nature of their claws is the 

This state of affairs is the necessary result of the 
process of their development. There is earthy sub- 
stance in the bird's body which courses along and 
issues out and turns into parts that are useful for 
weapons of offence. When it courses upwards it 
produces a good hard beak, or a large one ; if it 
courses downwards it produces spurs on the legs or 
makes the claws on the feet large and strong. But 
it does not produce spurs and large claws simul- 
taneously, for this residual substance would be 
weakened if it were scattered about. Again, some- 
times this substance makes the legs long ; and in 
some birds, instead of that, it fills in the spaces be- 
tween the toes. Thus it is of necessity that water- 
birds either are web-footed, simply, or (if they have 
separate toes) they have a continuous fan or blade, 
as it were, running the whole length of each toe and 
of a piece with it. 

From the reasons just stated it is clear that feet 
of this sort are the result of necessity, it is true ; but 
they conduce to a good end and are meant to assist 
the birds in their daily life, for these birds live in the 
water, and while their wings are useless to them, 
these feet are useful and help them to swim. They 

" See above, note on 648 a 16. 

o 411 


694 b 

10 at KcoTTaL rots TrXeovai KaV to. Trrepvyia roZs IxOv- 
GLV Sto KOI iav rajv yikv to. Tnepvyia u<f)aXfi, rcjv 
8e TO fiera^v tojv ttoScov, ovKeri viovcnv. 

"EiViOL Se /jLaKpoGKeXels tojv opvidcxjv elaiv. atriov 
8* on 6 ^los rojv tolovtojv e'Aeios" ra 8* opyava 
TTpos TO epyov r) ^vois TToieZ, aXX ov ro epyov npos 

lo ra opyava. 8ia fiev ovv ro fJLrj TrXcora etvat ov 
crreyavoTToSa ian, Slol 8e ro ev VTvetKovrL etvat rov 
^Lov fiaKpouKeXrj kol fiaKpoSaKrvXa, /cat ras" KafjL- 
TTOis exovGi ttXclov? iv roL£ SaKTvXoL? ol TToXXol 
avrcjv. €77et 8' ov TTrrjruKa fiev, ck ttJs" 8' avrrjs 
vX7]s iarl rrdvra, rj et? ro ovponvyiov avroZs rpo<fyr] 

20 els ra GKeXrj KaravaXLOKOfxevr] ravra rfv^iqaev. 8t6 
/cat ev rfj Trr-qoei dvr* ovpoTTvyiov xP^Jv'^oll aurots" 
TTerovrai yap OLTTorcLvovres et? to OTnodev ovro) yap 
avroL? ;^p?]crt/xa ra OKeXr], dXXcj? 8' ep^rrohit^OLev dv. 
Ta 8e ^paxvGKeXrj {ra) UKeXrf rrpos rfj yaorpl 
€XOvra TTerovrai' rois fJLev yap avrcJov ovk epTroSt- 

25 ^ovGLV ol TToSes ovroj , rols he yapipd)vv^L rial npo 
epyov elol npog rrjv dpTrayqv. 

Tojv 8' exovrcov opvlBojv rov au;^eVa paKpov ol 
pev TTaxvrepov exovres TTerovrai eKrerapevco rep 
avx^vi', ol he XeTrrorepov^ ovyKeKappevcp- CTTiTrero- 
pevois yap hid rr]v OKeTTiqv -^rrov evdpvTrrov eariv. 

695 a laxlov 8' exovoi pev ol opvides Trdvres fj ovk dv 

ho^aiev ex^iv, dXXd hvo prjpovg hid ro rov lax^ov 
prJKos' VTTorerarai yap pexpi pear]? rrj? yacrrpos. 
atriov 8' on hirrovv eori rovro ro l,a)ov ovk opOov 

^ KOL \l>. Ogle : oin. vulg. 

^ ra 8e ^paxvoK^Xi) PY6 ; correxi : Ivia hk jSpaxea <Td Lang- 
kavel> oK€\-q vulg. 

^ AeTTTOTepov Peck : Actttov koL fiaKpov vulg. : [kol fiaKpov] 
seel. Rackham. 


are like oars to a sailor or fins to a fish. A fish that 
has lost its fins can no longer swim ; nor can a bird 
whose webs have been destroyed. 

Some birds have long legs, owing to their living in 
marshes ; for Nature makes the organs to suit the 
work they have to do, not the work to suit the organ. 
And these birds have no webs in their feet because 
they are not water birds, but because they live on 
ground that gives under them they have long legs 
and long toes, and most of them have additional joints 
in their toes. Furthermore, though these birds are 
not great fliers, they are composed of the same ma- 
terials as the rest, and thus the nutriment which in the 
others goes to produce the tail feathers, in these is 
used up on the legs and makes them grow longer, and 
when in flight these birds stretch them out behind 
and use them in place of the missing tail feathers : 
placed thus, the legs are useful to them ; otherwise 
they would get in the way. 

Short-legged birds keep their legs up against the 
belly while they are flying, because if the feet are 
there they are out of the way ; the crook-taloned 
birds do it for an additional reason : the feet are 
convenient for seizing prey. 

When a bird has a long neck, this is either thick and 
is held stretched out during flight ; or it is slender 
and is bent up during flight, because being protected 
in this way it is less easily broken if the bird flies into 
anything. All birds have an ischium, but in such 
a way that they would not appear to have one ; it is 
so long that it reaches to the middle of the belly and 
looks more like a second thigh-bone. The reason for 
this is that a bird, although a biped, does not stand 



695 a 

{6V)/ COS et ye ers^e, KadaTrep iv rotg dvOpcoTTots ^ 
5 TOL9 rerpaTTooLv, oltto rrjs eSpas f^po-x^ 'T'o lgx^ov 
Kal TO a/ceAos" €v9vs ixopLevov, rjSvvdreL dv oXcos^ 
iordvai. 6 fiev yap dvOpcoTTog opdov, tol9 Se t€- 
TpdnooL TTpos TO ^dpos CKeXr] efXTrpoadia VTTeprjp^i- 
orai. OL S' opviOes ovk opOol fikv 8id ro vavcjheis 
etvau rrjv cf)vaiv, GKeXrj 8' ifiTrpoodta ovk e^ou- 

10 GLV Std TO TTTepuya? ^X^^^^ ^^'^^ avrcjv. dvrl he 
rovTov [xaKpov rj <f)vuLS ro lax^ov rroLiqaaaa ctV 
fieaov TTpoarjpeLoev evrevSev 8' V7Ti9r]K€ rd OKeXr], 
OTTOJs looppoTTov ovTOS Tov ^dpovs evOcv Kal evOev 
7rop€V€o9aL SvvrjraL Kal pLevetv* hi tjv fiev ovv 
air Lav hiTTovv eorlv ovk opddv 6v, etprjrat' rod S* 
doapKa rd GKeXr) elvau rj avrrj alria Kal inl rdjv 
rerparrohajv, VTrep Tys" Kal irpoodev eLprjTat. 

15 TerpahaKrvXoi 8' etcrt rravreg ol opvideg 6pLoicx)s ol 
oreyavoTTohes tol? GX^'^dTTOGLV [rrcpl ydp rod arpov- 
6ov rod Al^vkov vorepov hiopiovpiev, on htxp^Xos, 
dfjba rot? XoLTTolg ivavrLOjjJiaGLV ols e;^et rrpds rd rdJv 
opvidojv yevos). rovrcov 8' ol fiev rpelg epLTTpo- 
adev, 6 8' els oTTiodev npos dcr^dActav dvrl Trrepvrjs' 

20 /cat rojv puaKpoaKeXajv AetVet rovro /card fxeyedos, 
olov ovfJif3€^7]K€v ivl rTjS KpeKOS' rrXeiovs 8' ovk 
kxovGi haKTvXovs .^ irrl fxev ovv rdJv dXXojv ovrojs 
7) rdJv haKrvXcov ex^i deois, rj 8' 'Ivy^ hvo jxovov 
ex^t, rovs ejXTTpooOev Kal hvo rovs oTnaOev^' a'iriov 

^ <ov> Rackham, cf. 1. 14 infra. 

^ oXws PQU, Og-Ie : ofyQov vulj^. 

^ correxi ; exovaiv Sia rovro rrrepvyas exovoiv vulg. {mipu- 
ya?, 8e altero ix°^^^^ omisso, Y, Ogle, qui post 8ia touto 



upright ; and if it had an ischium which extended 
only a short way from the fundament and was fol- 
lowed immediately by the leg (as in man and the 
quadrupeds), it would be unable to stand up at all. 
Man can stand upright, and quadrupeds have fore- 
legs to support their forward weight ; birds, how- 
ever, neither stand upright (because they are dwarf- 
like), nor have forelegs (because they have wings in- 
stead). ** By way of compensation, Nature has made 
the ischium long, reaching to the middle of the 
body, and has fixed it fast, while beneath it she has 
placed the legs, so that the weight may be equally 
distributed on either side and the bird enabled to 
walk and to stand still. This shows why birds are bi- 
peds although they are unable to stand upright. The 
reason why their legs are lacking in flesh is the same 
as for all quadrupeds and has been stated already.^ 

All birds, web-footed or not, have four toes on each 
foot. (The Libyan ostrich will be dealt with later, ^ 
and its cloven hoof and other inconsistencies with the 
tribe of birds will be discussed.) Of these four toes, 
three are in front, and the fourth is at the back in- 
stead of a heel, for stability. In the long-legged 
birds this toe is deficient in length, as for instance in 
the Crex. Still, the number of toes does not exceed 
four. This arrangement of the toes holds good gener- 
ally, but the A\Tyneck is an exception, for it has only 
two toes in front and two at the back. This is because 

" See above, 693 b 3 ff . 

* See 689 b 10 ff. 
<= At the end of the book. 

* ixevetv Y6 : fievrj vulg. 

' Sia TTjv orevoTT^ra rod (jkcXovs add. PY6. 

' efjLTTpoadev . . . oniadev Karsch : OTnadev . . . efXTrpoodev vulg. 



25 O OTt TjTTOV €GTLV aVTrjS TO OOJfXa 7Tp07T€Te£ €771 TO 

rrpoodev rj to tcov d'AAcov. 

"Opx^'-S" ^' exovGL jjLev Trdvres ol opvides, ivros 
8* e^ovGiv 7] 8' alria iv roXg Trepl ras yeviueis 
Xe-)(B'qG€Tai rcov l,cocjv. 
695 b Td fiev ovv Tcbv opviOojv fjLopia rov rpo-nov exei 


XIII. Td 8e Tcov IxOvojv yevos eVt piaXXov k€koX6- 
jScoTat TCOV e/cTo? popicuv. ovtc yap GKeXrj ovTe 
X^lpas OVT6 TTTepvyas exovGLV {e'lprjTaL 8e Trepl tov- 
bTOJV 7] atVta TTpoTepov), dAA' d'Aov airo ttj? K€(f)aXrj? 
TO KVTog Gvvex^s Igtl P-^xp^ Trjs ovpas- TavTrjv 8' 
ovx opolav exovGL TrdvTes, dXXd tol pcev TTapa-nXrj- 
CTtW/ Tcjv 8e TrXaTeajv eVta aKavdcJoSrj /cat p,aKpdv 
Tj eKeWev yap av^rjGLS yiveTai els to ttAcitos", olov 
€GTL vdpKais Kal rpvyoGL /cat et Tt toiovtov d'AAo 
10 creAa^^^ds" eGTiv. tcov pLev ovv tolovtojv aKavOojhes 
Kal p.aKp6v TO ovpalov eGTLv, eviojv he GapKchhes pev 
^paxv he hid Trjv avTrjv acTLav 8t' jjvTrep Tat? 
vdpKais- hia^epei yap ovhev, iq ^P^'Xp H-^^ GapKOJ- 
heGTepov he, rj pLaKpov p,ev aGapKOTepov 8' etvat. 

'E77t he T(x)v ^aTpdxcov to evavTLOv Gvpi^e^-qKev 
16 8td yap TO pLTj GapKOjhes etvat to TiAaTOS" avTcov 
TO epLTTpoGOiov, oGov d(j)fi py]T ai GapKOjhes, irpos to 
OTTLGdev avTOJV^ edrjKev rj <f)VGLS Kal ttjv ovpav. 

OvK exovGL 8' aTTTjpTripLeva KCJoXa ol Ixdveg hid to 
vevGTLKYjv etvat ttjv <^uCTtv avTwv KaTa tov ttjs 
ovGtas Adyov, evret ol;t£ irepiepyov ovhev ovTe pidTr]v 

^ fjL€v aAAa TT. P : fiev afir) it. Piatt : fiev TTapanX-^oia <.toIs 
irrepvylois) Ogle, similia voluit Thurot. 
* avTwv U : avTo vulg. 

« See Degen. an. 714 b 4 fF., 719 b 11. 

PARTS OF ANIMALS, IV. xii.-xiii. 

the weight of its body tends forward less than that of 
other birds. 

All birds have testicles, but they are inside the 
body. The reason for this will be stated in the 
treatise on the different methods of generation 
among animals.^ 

This concludes our description of the parts of Birds, (iii.) Fishes ; 

XIII. In the tribe of Fishes the external parts 
are still further stunted. Fishes have neither legs, 
hands, nor wings (the reason has been stated earlier), 
but the whole trunk has an uninterrupted line from 
head to tail. Not all fishes' tails are alike ; but the Tail, 
general run of them have similar tails, though some 
of the flat-fish have a long, spiny one, because the 
material for the tail's growth goes into the width 
of the fiat body : this happens in the torpedo-fishes, 
in the Trygons, and any other Selachians of the same 
sort. These have long, spiny tails. Others have 
short, fleshy ones, and for the selfsame reason : it 
comes to the same thing whether the tail is short 
and has a good deal of flesh or long with little flesh. 

In the fishing-frog ^ the opposite has taken place. 
Here, the wide, flat part of the body in front is not 
fleshy ; Nature has taken the fleshy material away 
from the front and added an equivalent amount at 
the back — in the tail. 

Fishes have no separate limbs attached to the body. 
(a) This is because Nature never makes anything that 
is superfluous or needless, and by their essence and 
constitution^ fishes are naturally swimmers and so 

^ Lophius piscatorius, known as the " goosefish " in 
U.S.A., erroneously inchided by Aristotle {De gen. an. 
754 a 25) with the Selachia, though he observed that it 
diflFered in many important points. 

" Logos : see Introduction, pp. 2Q f. 



695 b ^ 

20 Tj (jyvois TTOiet. inel 8* evai/xa eart Kraro, rrjv 

ovoiav, hia iiev to vevoTiKo. elvai m^pvyia ex^L, Sta 
Se TO firj ne^eveiv ovk e;^et TroSa?* t^ ycip rcov ttoScov 

TTpOodeULg 77/30? TT^V €7TL TO) TTehicp KLVqOLV ;)^pT^atjLto? 

ianv. dfia Se Trrepvy la rerrapa kol irohas ovx 
OLOV r e;)(etv, ovh^ aAAo /ccoAov roiovrov ou3ev 
25 evaifia yap. ol 8e KopSuAot Ppdyxio, exovreg TToSa? 
exovGiv TTrepvy la yap ovk e;)(;oi;CTtv, aAAo, tt^v oupav 
[lavcnSr] Kal irXaTelav. 

''E;)(0UCTt Se Tcov IxOvojv ogol jjltj TrXarelg, KaOdnep 
^dro? Kal rpvycov, rerrapa Trrepvyca, Svo ptev ev 

696 a Tot? TTpaveai, Bvo S* iv TOts" VTTTLOLS' ttXelcx) Se 

rovTCov ouSetS", dvaipLoi yap dv rjoav. rovra)v 8e tcx 
jLtev eV to) Trpavel gx^^ov Trdvres exovon, rd 8* eV 
Tot? VTTTLOLS €i'LOi Tcov jjLaKpwv Kal vdxog eXOVTOJV 
I OVK exovGLV, OLOV iyx^Xvg Kal yoyypos Kal Keorpeojv 
Tt yevos TO ev rfj Xipvrj rfj iv Stoats', ocra 8' iarl 
pLaKpo(f)V€aT€pa Kal 6<f)Ld>hri p^aXXov, olov op.vpaiva, 
ovhkv exovGL 7TT€pvyLov aTrAcus', aAAo, rals /ca/XTrat? 
KLVOVvrai, p^pdS/xevat ro) vypqj ajGirep ol 6(jieis rfj 
yfj' Tov avTov^ yap ol 6<^€L£ rpoirov^ viovGiv ovirep 
10 cttI TTJs yrjs epTTovGiv. alria 8e rod [xr] ^x^lv tovs 
6(f)icoSeLs TCOV lxOvcx)v TTTepvyia, TJnep Kal tojv 
6(f)€a>v rod diroSa? elvai. to 8' acTiov ev TOtg irepl 
rropeias Kal Kivrjoeois tojv ^coojv e'iprjTai. t) ydp 
KaKcog dv eKivovvTO, TeTTapot Gr]p,eLOL? KLvovpceva 

^ TOV avTov Peck : tovtov vulg. 

2 Ol o<f)€is TOV rpoTTOv Y6: TOV delevi: tov Tpoirov ol o</)eis 

<» The Cordylus was probably the larval form of some 
triton or ne%vt, such as Triton alpestris or Salamandra atra, 
which retains its gills till it is well grown (D'Arcy Thompson). 

" i.e. pectoral. • i.e. ventral, 



need no such limbs. But also (6) they are essentially- 
blooded creatures, which means that if they have four 
fins they cannot have any legs or any other limbs of 
the sort ; so they have the fins because they are 
swimmers and do not have the feet because they are 
not walkers (when an animal has feet it has them 
because they are useful for moving about on land). 
The Cordylus,^ however, has feet in addition to its 
gills, since it has no fins, but only a scraggy flattened- 
out tail. 

Excluding flat-fish (like the Batos and Trygon), fish Fins, 
have four fins : two on their under and tw^o on their 
upper surface, never more, for then they would be 
bloodless animals. Almost all fishes have the two 
upper ^ fins, but some of the large, thick-bodied fishes 
lack the under ^ two — as for instance the eel and the 
conger, and a sort of Cestreus that is found in the lake 
at Siphae.'^ Fishes that have even longer bodies than 
these, and are really more like serpents (as the 
Smyraena^), have no fins at all, and move along by 
bending themselves about : that is, they use the 
water just as serpents use the ground. And in fact 
serpents swim in exactly the same way as they creep 
on the ground. The reason why these serpent-like 
fishes have no fins and the reason why serpents 
have no feet are the same, and this has been stated 
in the treatises on the Locomotion and Movement of 
Animals. f {a) If they had four motion-points, their 
movement would be poor, because the fins would 

<* In Boeotia, on the south coast near Thespiae ; now 
Tipha. Aristotle refers to this Cestreus of Siphae again, 
De incessu an. 708 a 5. Cf. also Hist. An. 504 b 33. 

* Probably Muraena Helena. 

' See Be incessu an. 709 b 7 ; perhaps the other passage 
which Aristotle has in mind is 690 b 16, in this book. 

0-1 419 


696 a ^^ ^ ^ T 

(etVe yap crvveyyvs etxov ra Tnepvyia, /xoyt? o-v 

15 eKivovvTO, eire TToppco, 8ta ro rroXv pLera^v)' el 
8e TxAeto) TO. KLVTjTLKCi CTT^jLteta erj^oi^, ciVat/xa av t^v. 
7^ S* aiJTT) alria /cat eVt rcov Suo piovov i^ov- 
rojv TTTepvyia l)(^9v(jov ocjyiojh'q yap eon Kal eu- 
pLrjKearepa, Kal )(prjTai rfj Kapupei dvrl rcov hvo 
TTTepvyicov. Sto Kal ev rep ir^po) epTTOvai Kal t^coat 

20 TToXvV XPOVOV, Kal TO, pL€V OVK €1)6 V , TO. S' OLKela 

TTJs Tre^r]? ovra (j)VO€a)s tjttov aorrapit^ei. 

AvTOJV Se Tcov TTrepvyicov ra ev rols Trpaveaiv ex^i 
ra Svo e^ovra TrrepvyLa ptovov, ocra pirj KOjXverai 
Sta TO TiXdros' ra S' e^ovra irpos rfj Ke(f)aXfj ex^t 
Sta ro pLT) ex^^y pLjJKOs ev rep roircp, a> dvrl rovra>v 

25 KLVTjGeraL' errl yap rrjv ovpdv TrpopLrjKes ro rcov 
roiovrcjv eorlv IxOva^v ocbpLa. ol he ^droi Kal ra 
roiavra dvrl rojv Trrepvyiojv rep eoxdrcp irXdrei 
veovoLv. rd 8* rjrrov exovra TrXdros nrepvy ta 
exovGLV, otov 7)^ vdpKTj Kal 6 ^drpaxos, ra (^pi^vY ev 
rep TTpavel Kdrco hid rd nXdros rcov dvoj, rd S* ev 
rots virrioig Trpds rfj Ke^aXfj [ov ydp KOjXveL KiveZ- 

80 cr^at rd TrXdros) ' aAA' dvrl rod dvco eXdrro) ravra 
rdv kv rep npaveX ^x^'" V ^^ vdpKrj irpos rfj ovpa 
ex^t. rd hvo Trrepvyua- dvrl he rcov hvo rep nXdrei 
XP'TJr at ex)? hval nrepvyioLS eKarepep rep rjpLLKVKXiep. 
He pi he rcov ev rfj KeefyaXfj pLopleov Kal alcjdr]r7]- 
piejjv etprfr ai Trporepov. 

^ TO. S' -^TTov . . . olov rj V : tj be tantum vulg. 
2 <[x(v> Langkavel. 



either be very close together, or else a long way apart, 
and in either case would not move easily. (6) On the 
other hand, if they had more than four motion-points 
they would be bloodless creatures. The same reason 
holds good for those fishes that have only two fins. 
These also are serpent-like and fairly long, and they 
use their power of bending instead of the two missing 
fins. And this enables them besides to crawl about 
and to live a good length of time on dry land ; and 
it is some while before they begin to gasp ; indeed, 
those which are akin to the land-animals are affected 
even less than the others. 

Except for those whose width and flatness prevents 
it, all fishes that have only two fins have the upper * 
ones ; and these fins are by the head, because there 
is no length of body just there which they could use 
instead of fins for propulsion — length such as fish 
of this sort have towards their tail-end. The Batoi 
and such fishes swim by means of the edge of their 
flat surface Mhich they use instead of fins. Fish 
which are not so flat, such as the torpedo-fish and the 
fishing-frog, possess fins, but they have their upper 
fins toward their tail-end owing to the flatness of 
the forepart, and their under fins near the head (since 
the flatness of the fish does not prevent its motion) ; 
but the under ones are smaller than the upper ones, 
to make up for being placed forward. The torpedo- 
fish has two of his fins by his tail ; and instead of 
these two he uses the wide piece on each of his semi- 
circles ^ as though it were a fin. 

We have already spoken of the parts in the head 
and of the sense-organs. 

" i.e. pectoral. 
* Cf. De incessu an. 709 b 17, 



696 a ^ 

"IStor 8* ex^i^ TO Tcov IxOvojv ylvog TTpos raAAa ra 
696 b eVat/xa t,o}a ttjv rcov ^payxiojv cf)V(JLV 8t* t^v 8' 
alriav, eipr^rai Iv roXs irepl dvaTTVoi^s . /cat l^et 8e 
TO. e^ovTa ^pdyxi'<^ to, juey e77t/<:aAi;/.tjLtaTa rots' 
^payxiOL?, rd 8e aeXax^] rrdvra} dKdXvnra. airiov 
5 8' ort ot jLtev d/cav^ojSets' etcrt, to 8' eTrt/caAujLt/xa 
d/cav^a>8es", rd 8e aeAd;)^!^ Trdvra x^v^pdKavBa. ert 
8' 9^ KLV7]GLg Tojv fjL€V vcoOpd" 8td TO jLtT^ aKavBajhr] 
elvai pLrjSe vevpajSr], rcov 8' aKavOcoScov rax^tCL' tov 
8* eTTt/caAJ/u/xaros" Ta;)(etav 8et yiveoOai rrjv Kivqaiv 
wGTTep ydp TTpos eKTrvo-qv rj rcov Ppayx^(J^v iorl 

10 (j)VOis. 8td TOVTO ToZs o-eAa;^tu8eo-t /cat avrcDv rcDy 
TTOpojv 7) Gvvaycoyr] yiverai rwv ^payx^ajv, /cat ov 
Set eVt/caAujLtjLtaros', ottojs" yivrjTai rax^la. 

Ot jLtev ouv auTo);^ exovoi ttoAAo, ^pdyx^cL ol 8' 
oAtya, /cat ot /xev 8i77Aa ot 8' ctTrAa* to 8' eoxoLTOv 
drrXovv ol TrAetorot. (t'57v 8' d/cptj8etav €/c tcDv 

15 dvaropLUJV irepl rovrcov /cat eV Tat? loropiais Tats" 
Trept TO, ^a>a Set Oecopelv.) alriov 8e tou ttXtjOovs 
/cat TTys" oAtyoTT^TO? TO Tou ev T7y /capSta depfjLov 
ttXtjOos /cat oAiyoTT^s" Odrroj ydp /cat loxvpoTepav 
Trjv KLVTjoiv 8et etvat TOts" TrXeioj 'ixovoi depiJLorrjra. 
TCt 8e TrAeio) /cat StTrAa ^pdy;^ta roLavrrjv ex^L Tr)v 

20 (f)vaLV pidXXov rcx)v aTrXcov /cat cAaTTOvojv. 8t6 /cat 
eVta auTtoi/ e^o) ^T^y Suyarat ttoAliv ;!^povov, rcDv 
ixdvTOJV iXdrroj /cat '^ttov iyKparrj rd ^pdyxt'O-, 
olov iyx^Xvs /cat ooa ScfiLcoSrj- ov ydp ttoXXtj? 
Seovrai Karaipv^ecns. 
"EiX^t, 8e /cat Trept to oropia hia^opds. rd [xev 

25 yd/) /car' dvTLKpv e;)^et to aTo/xa /cat ets" to irpoadev, 

^ (xoiSpoLKaiOa yap) post Travra vulg., om. P. 
^ 17 KivTjQis . . . vcodpa Y : ai KivT^acts . . . vwOpal Vulg. 


The peculiarity whicli marks oft' fishes from the GiUiu 
other blooded animals is the possession of gills. It 
has been explained in the treatise on Respiration ° why 
they have them. All fishes have coverings over their 
gills, except the Selachia, none of which have them. 
This is because their bones are cartilaginous, whereas 
other fishes' bones are of fish-spine, and this is the 
substance out of which the coverings are made. And 
again, the Selachia move sluggishly owing to their 
lack of fish-spine — and of sinews — while the spinous 
fishes move quickly, and the movement of the cover- 
ing must be a quick one, for gills are a medium for 
expiration of a sort. On this account in the selachian 
group of fishes the passages of the gills can close up 
by themselves, and no covering is needed to make sure 
they close quickly. 

Now some fish have many gills, some have few ; 
some have double ones, some single. The last one 
is nearly always a single one. (For precise details 
consult the Anatomical treatises and the Researches 
upon Animals.^) The number of gills depends upon 
the amount of heat in the heart. The more heat an 
animal has, the quicker and stronger must be the 
movement of its gills ; and if the gills are numerous 
and double they are better adapted for this than if 
they are few^ and single. And on this account, some 
fishes (e.g. the eels and the serpentine fishes) which 
need but little cooling, as is shown by their having 
only a few weakish gills, can live a long time out of 

Fish differ also with regard to the mouth. Some Mouth, 
have their mouth right at the tip, straight in front ; 

• At 476 a 1 ff., 480 b 13 flf. 
^ At 504 b 28 ff. 



696 b ^ ^ ^ ^ ^ ^ 

ra S* ev roZs vtttlols, olov ot re SeXcfylves^ koI tol 

aeXaxcoBr]' Sto /cat virria gt pec/to fxeva Aa/xjSavet rr^v 
rpocjy-qv. (^atVerat 8' rj (jyvais ov (jlovov oojTqpias 


aTp€i/j€L Gw^erai rdAAa ^pahwovrtov Trdvra yap 
80 ra roiavra ^a)ocf)dya eoriv), dWd /cat Trpos ro fir] 
OLKoXovOetv rfj Xaifiapyla rfj nepl Tr]V Tpo(f)TJv' paov 
yap Xajx^dvovra hi€(j>d€ip€T* av Sta rr^v rrX'^paxjiv 
rax€a>s. Trpos Se tovtols Trept^epTj /cat XeTTrrjv 
exovra ttjv rov pvyxovs (j>VGiv ovx olov t €V- 
hiaiperov €X€LV. 

"Ert Se /cat rcov dva> to arojita Ixovtojv ra fiev 

697 a dveppcoyos e;)(et to GTOfia ra Se fivovpov, OGa fiev 

GapKO(f)dya, dv€pp(x)y6s, oiGirep rd KapxapdSovra , 
Sid TO iv Toj GTopiari elvat roXg tolovtols ttjv Igxvv, 
OGa 8e fjLT] GapKO(f)dya, pLvovpov. 

To Se SepfjLa ol fxkv Xemhajrov exovGiv avrojv {r} 
6 Sc AeTTts" Std XafjL7Tp6r7)Ta /cat XeTrronqra rov gcL- 
[laros d^tWarat) , ot 8e rpaxv, olov pivt] /cat jSaro? 
/cat Tct roiavra' iXdxtorra Se rd Aeta. rd 8e oreAd;;^T7 
dAe7rtSa>Ta /xev rpax^a 8' eart 8td ro x^^^pdKavda 
clvac ro ydp yecohes eKeWev rj (f)VGis els ro Sepfia 
KaraviqXojKev . 
10 "Opx^^s 8* ouSet? e;)(et Ix^^^ ovr c/crd? ovr* ivros 

^ SeA<^tve? non probant Frantzius, Ogle; similia Hist. An. 
591 b 26 secludunt Aubert et Wimmer. 

" This statement about dolphins, though repeated at Hist, 
an. 591 b 26, is incorrect, and as Aristotle was familiar with 


others have it underneath {e.g. the dolphin '^ and the 
selachians) and that is why they turn on to their backs 
to get their food. It looks as if Nature made them 
do this partly to preserve other animals from them, 
for they all prey on living things, and while they are 
losing time turning on to their backs the other things 
get away safely ; but she did it also to prevent them 
from giving way too much to their gluttonous craving 
for food, since if they could get it more easily they 
would presently be destroyed through repletion. 
Another reason is that their snout is round and small 
and therefore cannot have much of an opening in it. 

There are differences too among those that have 
their mouth above. With some it is a great wide 
opening (these are the flesh-eaters, as e.g. those mth 
sharp interfitting teeth, whose strength is in their 
mouth) ; with others (the non-flesh-eaters) it is on 
a tapering snout. 

As for the skin : some have a scaly skin (these Skin, 
scales are shiny and thin and therefore easily come 
loose from the body) ; others have a rough skin, e.g. 
the Rhine and the Batos and such. Those with 
smooth skins are the fewest. Selachia have skins 
which are scaleless but rough, owing to their bones 
being cartilaginous ; instead of using the earthy 
matter on the bones Nature has used it for the skin. 

No fish has testicles ^ either without or within. Nor Testicles. 

the creature, some editors consider this reference to be an 

^ By this Aristotle does not mean that fish have no organ 
for the secretion of sperm, but that they have no organ similar 
in shape and consistency to those of mammaha, etc. He calls 
the corresponding organs in fish not testes, but tubes, or roe. 
Aristotle's statement does not, of course, include the Selachia, 
which have compact, oval testes. 



697 a 

(ouS* aXXo Tt Tcov OLTToScxJV ovSev, 8to ot)S' ol 6(j)€is), 

TTopov he rod TrepiTTcofiaTog Kal rcov Trepl rrjv 
yiveoiv rov avTOV, KaOaTvep /cat raAAa cootoko} 
TTOLvra Kai^ rerpoLTroSa, 8ta ro (jltj €)(€lv kvotlv 
firjhe ylveaOat Treptrrco^' aurot? vypov. 

16 To pev ovv rcov 1-)(6vcl>v ylvos Trpos raAAa ^oia 
raura? e;)^et ras" Sta^opa?, ot Se heXcjuves Kal at 
(fioXaivai Kal iravra ra roiavra rcov ktjtcjv ^pdy)(La 
fjL€V ovK exovaiv, avXov he hia to TTvevpiova e-x^eiv 
he-)(opieva yap Kara to oro/xa rrjv ddXarrav d(f)idaL 
Kara rov avXoi^. dvdyKrj puev yap he^aadai to 

20 vypov hid TO Xap^dveiv rrjV rpocfirjv ev ro) vypcp' 
he^dpieva 8' d<^teVat dvayKalov. ra piev ovv ^pdy- 
Xi'd eoTL xPV^f-f^^ '^OLS pLTj dvaTTveovoiv hi tjv S* 
air lav, eiprjrai ev Tots" Trepl dvaTTVorjs' dhvvarov yap 
dpia TO avro dvarrvelv Kal ^pdyxi'OL €;^etv aAAa npos 
rrjv d(f)eaiv rod vharos exovai rov avXov. Keirai 3' 

25 avroZs ovrog rrpo rov eyKe(/)dXov' hieXdp^ave yap 
dv aTTO rrjs pdx^cos avrov. atriov he rod nvevpLova 
ravr e^etv Acat dvairvelv, on ra pieydXa rcjjv t^wcxjv 
rrXeiovos heZrai Oepp^orrjros Iva Kivrjrai- hio 6 
TTvevpiojv eyKeirai avrols Oepp^orr^ros a)V rrXrip'qg 
aifiariKrjg . eon he ravra rponov rivd (^Kai)^ Tre^d 

80 Kal evvhpa- rov pev yap depa hex^rai cos" Tre^a, 
drroha 8' ecTt Kal Xapi^dvei eK rov vypov rr)v 
%^ h Tpo(f)rjv WGTTep ra evvhpa. Kal at ^to/cat he Kal 
at vvKrepihes hid ro e-napKJiorepit.eiv at piev rois 
ivvhpois Kal Tre^ot?, at he rois Trrrjvois Kal Trefots", 
Std Tovro dpi(j)orepcov re pierexovai Kal ovherepojv, 

1 Co^oTO/ca PSUY. 

* KOI (StTToSa Kai) Ogle. 

^ (/cai) Rackham. 



have any other footless animals, and this includes the 
serpents. In fish the passage for the residue and for 
the generative secretion is one and the same ; and 
this is so in all other oviparous animals, four-footed 
ones included. This is because they have no bladder 
and produce no liquid residue. 

Thus we have seen what are the differences to be inter- 
noticed in fish as a group as compared wdth other "Ltures : 
animals. Dolphins and whales and all such Cetacea, ^'•) Cetacea. 
however, have no gills, but they have a blowhole 
because they have a lung. They cannot help letting 
the sea-water enter the mouth because they feed in 
the water, and once it has got in they must get it out 
again, and they do so through the blowhole. Gills, 
of course, are of service herein to those creatures that 
do not breathe. The reason for this has been given 
in my book on Respiration'^ '. no creature can breathe 
and at the same time have gills ; instead, these 
Cetacea have a blowhole for getting rid of the water. 
It is placed in front of the brain, otherwise it would 
separate the brain from the spine. The reason why 
these creatures have a lung and breathe is that large 
animals need more heat than others to enable them to 
move ; consequently they have a lung inside them ^ 
full of heat derived from the blood. They are, in a 
way, land-animals as well as water-animals : they 
inhale the air, hke land-animals, but they have no 
feet and they get their food from the water as water- 
animals do. Similarly, seals and bats are in an inter- (ii.) Seaia 
mediate position. Seals are between land-animals ^""^ ^**** 
and water-animals, bats between land-animals and 
fliers : thus they belong to both classes or to neither. 
" References given above, see on 696 b 2, 



697 b ^ 

5 at re yap (fiajKai cos /xev evvSpoc 7708a? exovcnv, (Ls 

he Trejat nrepvyia^ [rovs yap oiriaQev TTohas l^Bv- 
coSet? exovGL 7ra/x7ray, ert 8e rou? oSovras" Trdvras 
Kapxapohovras Kal o^els)' /cat at vvKrepihes OJS fJiev 
TTTTjva exovcTL TToSag, wg Se rerpoLTToSa ovk exovai, 
Kal ovT€ KepKov exovcriv ovr^ ovpoTTvyiov, 8ta jJLev 

10 TO TTTiqva elvai KepKOV, Sta he ro rret,a ovponvyLOV. 
uvfx^e^rjKe 8' avrals rovr e^ dvdyKrjs' etVt yap 
hepjJLOTTTepoL, ovhev 8' e;\;et ovporrvyiov fxr] o-;)(tJo- 
TTTepov eK TOLOvrov yap irrepov yiverai to ovpo- 
TTvyiov. Tj he KepKos Kal efjiTTohiog dv rjv virdpxovaa 
iv rols TTTepoZg. 

Tov auTov he rpoTTOV Kal 6 arpovdos 6 Al^vkos' 

15 rd ixev yap opviOos ^x^c, rd he ^cpov Terpdnohog. 
<Ls fiev ydp ovk u)v rerpdirovs Trrepd €X€i, d)s 8' 
OVK a)V dpvLS ovre Trirarai fJuerecopL^oixevos , Kal rd 
Trrepd ov XPV^^I^^ irpos TrrrjaLv dXXd rpix^hr]' ere 
8e CO? fJiev rerpdnovs cjv pXecfiaplhag ex^L rds 
dvojOev Kal xjjiXos eon rd irepl rrjv Ke(f)aXr)v Kal rd 

20 dvo) rod avx^voSy wore rpix^oheorepas ^x^i'V rdg 
jSAe^aptSas, cos" 8' opvLs cov rd Kdrcodev eirrepoiraL' 
Kal huTTOVS fiev eoriv d>s dpvis, hixciXos 8* (hs 
rerpdirovs ' ov ydp haKrvXovs e;^et aAAa XV^^^' 
Tovrov 8' atrtov ort to {jueyedos ovk opvidos e;;^et 
dAAa rerpdiTohos' eAa;^toTov ydp dvayKalov elvau ro 

25 jJLeyeOos cos" KadoXov etVetv ro rojv opvidajv ov ydp 
pdhiov TToXvv oyKOV Kivelodai oaj/xaro? jxereajpov, 

^ TTTcpvyia Ogle : TTTcpuyas vulg. 


Seals, if regarded as water-animals, are anomalous in 
having feet ; if regarded as land-animals, in having 
fins (their hind feet are altogether Hke those of 
fishes — i.e. fins ; and all their teeth too are sharp and 
interlocking). Bats, too, if regarded as birds, are 
anomalous in having feet*^ ; if regarded as quadrupeds, 
in not having feet ^ ; furthermore, they have neither a 
quadruped's tail (because they are fliers) nor a bird's 
tail (because they are land-animals). This their lack 
of a tail like a bird's is a necessary consequence, 
since they have membranous wings, and no creature 
has a tail of this sort unless it has barbed feathers : 
such tails are always made out of barbed feathers 
And a tail of the other sort grovving among feathers 
would be a definite impediment. 

After the same style is the Libyan ostrich: in (iiiO.The 
some points it resembles a bird, in others a quadruped. ^ "° * 
As not being a quadruped, it has feathers ; as not 
being a bird, it cannot rise up and fly, and it has 
feathers that are like hairs and useless for flight. 
Again, as being a quadruped, it has upper eye- 
lashes, and it is bald in the head and the upper part 
of the neck, as a result of which its eyelashes are 
hairier than they would otherwise be ; as being a 
bird, it is feathered on its lower parts. Also, as 
a bird, it has two feet ; but, as a quadruped, it has 
cloven hoofs (it has hoofs and not toes). The reason 
is that it has the size not of a bird but of a 
quadruped. Speaking generally, a bird has to be 
very small in size, because it is difficult for a body of 
large bulk to move off the ground. 

« That is, of the sort that birds ought not to have, viz. on 
their winofs. 

* That is, of the sort that quadrupeds ought to have. 



Yiepl jikv ovv Tcbv fiopicDVy Sid riv atrtav eKaarov 
ioTLV iv roZs t,woi<s, elpiqTai Trepl ttolvtojv raJv ^ojcov 
Kad^ eKaarov tovtcjv 8e hiojpi(jp,iv(jJv i(f)e^rjs eori, 
30 ra 7T€pl ras yevioeis avrcjv SieXOelv} 

^ TovTcov . . . SicA^etv om. Yft, et statim incipiunt librum 
ds incessu. 



We have now spoken severally of all the animals : Conclusion. 
we have described their parts, and stated the reason 
why each is present in them. Now that this is 
concluded, the next thing is to describe the various 
ways in which animals are generated. 



Additional Note on 684 b 21-29 

Commentators agree that no satisfactory sense can be 
obtained from the first three Hnes of this passage as it stands 
in Bekker's edition. None has so far produced a remedy ; 
but an examination of the Arabic translation (or of Michael 
Scot's Latin translation made from the Arabic) shows plainly 
what has happened. In neither of these two translations is 
there any reference whatever to a diagram until 685 a 2. 
Thus the ms. from which our present Greek text is derived 
had been corrupted through the efforts of someone who tried 
to improve the text of 684 b 2-2-21 by inserting references to 
a diagram here also ; and the result is that these references 
have caused the complete loss of one important phrase (b 22) 
and serious corruption of another (b 24-25). Some disloca- 
tion has also been caused in the lines following, up to line 29. 

The two diagrams given in the ms. Z are obviously con- 
structed to suit the interpolated text. One of the mss. (Mer- 
ton 278) of Michael Scot's version has an entirely different 
diagram ; the three mss. of Scot at Cambridge have no 
diagram at all, nor has the Arabic ms. B.M. Add. 7511. 

I give below the passage as it appears in Michael Scot's 

Natura ergo istorum dvorum modorum est sicut diximus ; 
et propter hoc ambulant nniformiter'^ sicut accidit animalibus 
quadrupedihus et hominibus etiam. homo vero habet os in 
capite, scilicet in parte superiori corporis ; deinde habet 
stomachtcm, deinde ventrem, et post ventrem intestinum per- 
veniens ad locum exitus superjluitatis. iste ergo res in 
animalibus habentibus sanguinem sunt secundum hanc dis- 
positionem^ et post caput est clibanus, scilicet pectus^ et quod 
vicinatur ei. alia vero membra sunt propter ista, etc. 

I am much indebted to Dr. R. Levy for his kindness in 
reading this passage for me in the Arabic in Brit. Mus. ms. 
Add. 7511. 

* inuniformiter Caius 109 & Camb. U.L. II. 3. 16; fortasse igitur 
Bcribendum uniformiter et non inuniformiter. 



Additional Note on 693 b 3 

Explanation of Aristotle's terminology for describing the 
bending of limbs. 
When Aristotle is speaking about the bending of limbs, 
hackicards and foricards are relative to the direction in 

which the whole animal moves ; 
inwards and outwards are relative to the bulk of the body 
Thus, backwards means that the angle of the bent joint 
points backwards ; inwards means that the extremity of the 
limb is brought inv.-ards towards the body, that is, the angle 
of the bent jomi points away from the main bulk of the body. 
(" Inward " and "outward " bending thus have no connotation 
of " bandy-legs " and " knock-knees.") 

All four legs bend imcards ; 
Example (1) y^ 'K^\ The forelegs hen^ forwards : 
The hindlegs bend backwards. 

r, 1 /r^\ r v/ The leg bends inwards, and 

Example (2) f 3/ 


(See Be incess. an. 711 a 8 ff., Hist. An. 498 a 3 ff.) 



Additional Note on the ms. Z 

The following portions of the text of De partibus are con- 
tained in the Oxford ms. Z (see p. 50) : 

fol. 60^, 60^. I. 639 b 29 to 640 b 24. /xe'xpi to fiaXXov av 

fol. 61', 6 P. I. 644 a 25 to 645 a 17. KadoXov to rot? (^y in- 

Between these two folios it has apparently lost four folios, 
as well as one at the beginning of Book I and another at the 

fol. lf-19'. Book II. 

fol. 19^-36'. Book III, but the words ou ttoXv to cvpvxdipovs 
inclusive (675 a 30-b 27) are omitted, 
with no indication by the original scribe 
that anything has been omitted : this 
passage has been supplied by a later hand 
in the margins of fol. 35'^ and 36' and 
on 36^. 

Book IV is written by yet another (later) hand, and this 
Book occupies fol. 37'"-59v, at the end of which folio it breaks 
off at the words ra KoXovixiva (694 a 13). The rest of Book 
IV is lost. 

In the apparatus I have used the following abbreviations 
in quoting this ms. : 

Z Books I, II and most of III (first hand, c. a.d. 1000). 
Z^ indicates the reading of the first hand where this has 

been altered by another. 
Z^ indicates later correctors of Z^. 
Z indicates the readings of the ms. in Book IV. 

I have collated from photostats the whole of the portion 
written by the first hand, and the readings of Z quoted have 
been confirmed by reference to the photostats. 

I have used the symbol E when quoting the readings of 
E from 680 b 36 onwards, as this part of the ms. is written 
in a later hand. 




That the De incessu animalium is a genuine work of 
Aristotle himself has never been disputed. The De 
motu animalium has been regarded by many critics as 
a spurious work, though recent opinion has favoured 
its genuineness. Brandis, Rose and Zeller all con- 
demn it, but its Aristotelian authorship has been up- 
held by Werner Jaeger {Hermes, xlviii. pp. 31 ff.), who 
makes out a very strong case in its favour, and by the 
Oxford translator, Mr. A. S. L. Farquharson. Those 
who deny its authenticity rely mainly on the supposi- 
tion that there is a reference in 703 a 10-1 1 to the De 
spiritu. This treatise is generally admitted to be un- 
Aristotelian, but the reference, as Mr. Farquharson 
has pointed out, might relate equally well to numerous 
other passages in the Aristotelian corpus ; Michael 
Ephesius refers it to a treatise Tlepl Tpo(f>yj<i, not 
otherwise known. In style, vocabulary and syntax 
the De motu animalium is entirely Aristotelian, and its 
doctrine corresponds with that set forth in Aristotle's 
genuine works. 

Each treatise has its proper place in the scheme of 
Aristotle's biological works. Both are theoretical, 
the De incessu animalium, like the De partihus ani- 
malium, dealing with the material side of living things, 
and the De motu animalium, like the De generatione 
animalium, dealing with their consequential pro- 



The chief mss. of the De motu animalium are E, Y, 
P and S." Of these E, one of the most famous of 
AristoteUan mss., is the oldest ; Y is closely related 
to E. P and S are similarly related and form a second 

Of the De incessu animalium the principal mss. are 
Z, Y, U, S and P.« Of these Z is the oldest, and Y is 
closely related to it, while the other three mss. form 
another group. 

A full account of these mss. and their relations to 
one another will be found in the Introduction (pp. 
iv. ff.) of W. W. Jaeger's text (Teubner, 1913). 

The text used for the present translation is based 
on that of I. Bekker, all divergences from which are 
noted and the authority given for the reading adopted. 
Jaeger's text and apparatus criticus have been con- 
sulted throughout. 

The Commentary of Michael Ephesius (Com- 
mentaria in Aristotelem Graeca, xxii. 2, Hayduck, 1904?) 
has been of some assistance both for the text and for 
the interpretation, and the Latin version of Nicholaus 
Leonicus (died 1599)> printed in the Berlin Aristotle, 
Vol. Ill, has been constantly consulted. 

The two treatises have been translated into French 
by J. Barthelemy-Saint-Hilaire, and into English by 
Mr. A. S. L. Farquharson in the Oxford translation 
(1912). This translation with its ample explanatory 
notes constitutes much the most serious attempt that 
has been made to interpret these two treatises, and 
anyone who follows in Mr. Farquharson 's footsteps 
must necessarily be heavily indebted to him. 

E. S. F. 

*• For the meanings of these symbols see pp. 439 and 483. 



Chap. I. The origin of all movement must itself be un- 
moved. So if there is to be animal movement, something 
in the animal must be at rest. Hence joints are necessary. 

II. There must also be a resisting medium external to the 
moving animal. Illustration from the rowing of a boat. 

III. The nature of the " prime mover." The fable of 

IV. The " prime mover " is of necessity outside the 
universe. The movement of inanimate things must 
originate from animate things. 

V. Alteration, growth, generation and corruption as 
forms of motion. 

VI. How does the soul move the body ? Animal move- 
ment lies in the sphere of action. Its limitation in com- 
parison with eternal movement. 

VII. Animal movement the result of the syllogism of 
action, not of the speculative syllogism. Animal move- 
ment compared with that of automatic toys. 

VIII. ITie psychology of animal movement and the 
organic changes which accompany it. The cause of move- 
ment must be situated in a definite origin. 

IX. The two sides of the body are similar and can move 
simultaneously : both are moved by the soul. 

X. The motive power is " innate spirit." Comparison 
between the animal organism and a well-ordered civic 

XI. Involuntary and non-voluntary movements. Con- 



E= Codex Parisinus Regius 1853. 

Y= Codex Vaticanus 261. 

P= Codex Vaticanus 1339. 

S = Codex Laurentianus 81. 1. 
Leon. = Latin translation of Nicolaus Leonicus. 
Mich. = Greek commentary of Michael Ephesiug. 



3a I. Uepl Se KLVi^creojs rrjg rcov t,(Lcx)v, ocra filv 
avTcov TTepl eKaarov vnapx^L yivos» kol rives 
SiacfiopaL, /cat rtVes" alriai tojv KaO^ eKaarov cru/x- 
^e^-qKOTWv avTOLs, irreuK€TTTai rrepl airavrtov iv 
irepoLS- oAcos" §€ Trepl rrjs Koivrjs alrias rod kl- 
5 velaOai KLvrjaLV oTTOuavovv (ra puev yap Trrrjciei kl- 
veiraL ra 8e vevorei ra Se iropeia rcov ^cpcov, ra 8e 
/car' dXXovs rponovg roLovrovs) imaKeTrreov vvv. 

"On fiev ovv dpx'^ "^^jv dXXcov Kivquecov ro 
avro iavro klvovv, rovrov^ 8e to oLKLvrjrov, 
/cat on ro irpajrov klvovv dvayKolov aKLvqrov 

10 elvai, hicxipiorai nporepoVy orerrep /cat Trepl kl- 
vqcreojs dtStou, TTorepov eanv tj ovk eon, /cat el 
ean, ris eGnv. Set he rovro firj jjlovov ro) Xoycp 
KadoXov Xa^elvy dXXd /cat eirl rcbv /ca^' e/caara 
/cat rcLiV alad-qrcov, 8t* dnep /cat rovs KadoXov 
^rjrovfiev Xoyovs, /cat e^' wv e(l)apjji6rreiv olop^eOa 

15 Seti^ avrovs. cjyavepov yap /cat eVt rovrojv on 
dSvvarov Kivelddai pLTjSevos rjpefxovvros, Trpcorov 
fjiev iv avroLS roZs Jcoot?. 8et yap, dv KLvrjrai n 
rd)V jJLOpLCOV, ripepLelv rr /cat 8td rovro at KajXTral 




I. We have inquired elsewhere ° into the details of 
the movement of the various kinds of animals, the 
differences between these movements, and the causes 
of the characteristics which each exhibit ; we must 
now inquire generally into the common cause of 
animal movement of whatever kind — for some animals 
move by flight, some by swimming, some by walking, 
and others by other such methods. 

Now that the origin of all the other movements is 
that which moves itself, and that the origin of this is 
the immovable, and that the prime mover must neces- 
sarily be immovable, has already been determined 
when we were investigating ^ whether or not eternal 
movement exists, and if it does exist what it is. And 
this we must apprehend not merely in theory as a 
general principle but also in its individual manifesta- 
tions and in the objects of sense-perception, on the 
basis of which we search for general theories and 
with which we hold that these theories ought to 
agree. For it is clear also in the objects of sense- 
perception that movement is impossible if there 
is nothing in a state of rest, and above all in the 
animals themselves. For if any one of their parts 
moves, another part must necessarily be at rest ; and 

* In the De partibus animalium. 
^ Physics viii. 258 b 4-9. 




rot? ^coots' eloiv. wGirep yap Kevrpco ;^/3ajvTat 
rat? KafiTTalg, /cat yiverai to oXov fiipos, iv cL r) 

20 KaiXTTTj, Kal €V Kal SvO, Kal €v6v Kal K€KaiJLjJL€VOV, 

Ixera^dXXoi' hvvdfxei Kal ivepyeia Sid ttjv KapLTT-qv. 
KapLTTTopievov 8e /cat KLVovpiivov to /xev /ctvetrai 
(jr}pL€Lov TO 8e piivei rcbv iv Tat? KapLiraZs, ojairep 
av €L rrjs hiapbirpov rj puev A /cat t^ A pLevoi, rj 8e 
B KLVotro, /cat yivoiro rj AT. aAA' ivravda puev 

25 8o/cet navra rporrov dStatpeTov eti^at to Kevrpov 
(/cat yd/) TO Kiveladai, cog (jyaai, rrXdrrovaiv iir 
avrcov ov yap Kivelodai} rwv pLaOrjpariKcov 
ovSdv), rd 8' iv rats KapiTratg hvvdpiei /cat ivepyeia 

8 b ylverai ore piev ev ore he hiaiperd. dAA' ovv 
del Tj dpxr] r) TTpds o, ff dpx'ij, ripepieZ Kivovpievov 
rod pLopLOV rod Kdrcudev, olov rov piev ^pa^iovos 
Kivovpievov TO wXeKpavov, oXov he tov kwXov 6 
(LpLOSi Kal Trjs p^ev Kv^pLTjs TO yovv, oXov he tov 
8 GKeXovs TO loxtov. OTL pLev ovv Kal ev avTO) 
eKaGTov TL heX €;\;etv 'qpepiovv, o9ev rj dpx^) 
TOV Kivovpievov ecTTai, Kal rrpog o aTrepeiSopievov 

* KivetaOai ESY : /cu'etrat P. 

* T) Trph$ 6, 5 Jaeger : t? irpos 8 rj EY : ij irpd^TT] ^ S: i] irpbaw 
(om. altero apxri) P. 

• e.g. the arm as an arm is one, but is divided into two at 
the elbow. 

" The term apxrj', which occurs frequently in this treatise, 
is difficult to render in English by a single word. It is some- 
times used generally of the " origin " of movement {e.g. 
701 b33), but more often of a localized "origin" of movement, 


it is on this account that animals have joints. For 
they use their joints as a centre, and the whole part 
in which the joint is situated is both one and two," 
both straight and bent, changing potentially and 
actually because of the joint. And when the part 
is being bent and moved, one of the points in the 
joint moves and one remains at rest, just as would 
happen if A and D in the diameter of a circle were 
to remain still while B moved, and the radius AC 
were formed. (In geometrical figures, however, the 
centre is considered to be 
in every respect indivisible — 
for movement, too, in such 
figures is a figment, so they 
say, since in mathematics 
nothing actually moves, — 
whereas the centres in the 
joints are, potentially and 
actually, sometimes one and 
sometimes divided.) Be that as it may, the origin ^ 
to which the movement can be traced, qua origin, 
is always at rest while the part below it is in motion 
— the elbow-joint, for instance, when the forearm 
is in motion, the shoulder when the whole arm is 
moved, the knee when the shin is moved, and the 
hip when the whole leg is moved. It is obvious, then, 
that every animal too must have in itself something 
that is at rest, in order to provide that which is 
moved with the origin of its movement, supported 

whether, as here, in a single member, or at the centre of the 
body, viz. the heart (701 b 25, 29), where a further idea of 
" ruling " seems to be implied {e.g. 703 a 37). It is also used 
sometimes in the literal sense of " beginning," and this and 
the meaning of " origin " of motion may occur in the same 
passage and cause confusion {e.g. 702 a 36-b 2). 

P 443 


698b . .. ,n r n. > ^ . 

Kat oAov aopoov KLvrjorjaerai /<at Kara fjuepog, 

II. 'AAAa ndaa tj iv avrw rjpejjLLa ojjlcos aicvpos, 
av pLTj TL e^coOev fj 0,77X0)9 rjpepiovv /cat oLKLvrjrov. 

10 a^Lov 8' iTTLGrrjCjavTas iTncjKeipaaOai Trepl rod 
Aep^^eVros" €X€i yap ri^v deojpiav ov fxovov ooov 
C77t ra 1,0)0 avvreivovaav , aAAa /cat 77pos" rr]v rod 
iravros KLvrjGLv /cat (f)opdv. cjoirep yap /cat iv 
avrcp 8et n aKiviqrov etvai, el fxeXXec KLveladat, 
ovrcos ert [xdXXov efco Set rt etvat rov t,a)OV 

15 OLKLvrjrov, npos o aTrepeiSofievov KLvelrai ro klvov- 
ixevov. et yap VTroScoGeL del, olov rots [xvol^ rots 
iv rij yfj^ rj rols ev rfj ajxp^o) TTOpevofievois, ov 
TrpoeicjLVy oz58' ecrrat ovre TTopela, el per) tj yrj fxevoL, 
ovre TTrrJGLg 7] vevcng, el pLT) 6 drjp rj rj OdXarra 
dvrepeihoi. dvdyKrj Se rovro erepov elvai rod 
KLvovfJievov, /cat oXov oXov, kol [xopLov fXTjSev elvau 

20 rov KLVovpbevov ro ovrws dKLvrjrov el 8e pLij, ov 
KLvrjdi^GeraL. p^aprvpiov he rovrov ro dnopov- 
fjievov, Sta Tt TTore ro ttXolov e^a>9ev puev, av rt? 
(LOfj ro) Kovrcp rov LGrov jj ri dXXo npoG^dXXojv 
pLoptov, KiveZ pahiojs, edv 8' ev avraj ris cov ro) 
irXoicp rovro Treipdrai irpdrreiv, ovk av KivrjGeiev 

25 ovr^ av 6 Tirvos ov6^ 6 Bopea? rrvecov eGCodev e/c 
Tov ttXolov, el rvypi Txveoiv rov rporrov rovrov 6v- 

^ fivfflv libri : ifivat. coni. Diels. 
' 7^ libri: fet^ coni. Farquharson. 

" It is doubtful whether the ms. reading will bear this 
interpretation, and 4p ttj 777 is probably corrupt. It is more 



upon which it will move both as an integral whole 
and in its several parts. 

II. Any quality of rest, however, in an animal is of 
no effect unless there is something outside it which is 
absolutely at rest and immovable. And it is worth 
while to stop and consider this dictum ; for the re- 
flection which it involves applies not merely to animals, 
but also to the motion and progression of the universe. 
For just as in the animal there must be something 
which is immovable if it is to have any motion, so 
a fortiori there must be something which is immov- 
able outside the animal, supported upon which that 
which is moved moves. For if that which supports 
the animal is to be always giving way (as it does when 
mice walk upon loose soil " and when persons walk on 
sand), there will be no progress, that is, no walking, 
unless the ground were to remain still, and no flying 
or swimming unless the air or sea were to offer resist- 
ance. And that which offers resistance must be other 
than that which is moved, the whole other than the 
whole, and that which is thus immovable must form 
no part of that which is moved ; otherwise the latter 
will not move. This contention is supported by the 
problem : Why can a man easily move a boat from 
outside if he thrusts it along with a pole by pushing 
against the mast or some other part of the boat, 
but if he tries to do this when he is in the boat 
itself, Tityus could not move it nor Boreas by blow- 
ing from inside it, if he really blew as the artists 

than likely that the comparison is with a mouse trying to 
walk upon a heap of corn. Farquharson emends iv ttj yy to 
eV Trj ^€1$, which would bear this meaning:. (The form ^erj, 
cp. Petrie Pap. ii. p. 69 (3rd cent, b.c), would be nearer to the 
MS. reading.) Diels' suggestion of fiu'>aiv for fivatu is in- 
genious, but does not give the required sense. 



698 b 

TT€p ol ypa(j)€.Zs TTOiovoiv e^ avrov yap ro TTvevfxa 

699a d^teVra ypd(f)OVGLV. edv re ydp T]pe/xa piTrrfj ro 

TTvevfid Tis idv r* Icrxvpoj? ovrcus war dvefiou 

TToielv Tov fxiyiarov, Idv re d'AAo rt fj ro piTrrov- 

fjLevov ^ (Ldovfievov, dvdyKT^ npajrov fiev rrpos 

ripepiodv n rCjv avrov jiopiwv drrepeLSoixevov dtOeZv, 

6 etra TrdXiv rovro ro jxopiov, r^ avro tj oS rvy^dvei 

jiopiov ov, rrpos rajv e^coOev n aTTOcrri^pit^oiievov 

jjieveiv. 6 Se ro ttXolov wOajv iv ra> ttXoloj avros 

wv Kal aTTOGriqpil^opiGvos Trpos to ttXoIov evXoyojs 

ov KLvel ro rrXolov hid ro dvayKalov etvai Trpos o 

aTToarrjpL^erac fievGLv avfi^atveL 8* avrw ro avro 

10 o r€ KLveZ Kal Trpos o aTTOGriqpit^^rai. e^codev 8* 
(h9a)v Tj eXkcov KLvei- ovOev ydp [xepos r) yrj rod 

III. ^A.TToprjGeie 8' dv ris, dp* et rt KiveZ rdv 
oXov ovpavov, etvai re Set aKLvqrov rovro KaV" 
fjLTjOev elvai rov ovpavov pLopiov fJ-rjS^ iv ro) 
ovpavaj. e'lre ydp avro KLVovjjievov KLveZ avrov, 

15 dvdyKrj rivos aKLV-qrov diyydvov KtveZv, Kal rovro 
purjhkv elvai piopiov rov klvovvtos' ecr^ evGvs dKLV7]r6v 
iari ro klvovv, 6poia>s ovhev eWat^ rod klvov- 
jjLevov pLopiov. Kal rovro y' opBcos Xeyovcnv ol 
Xiyovres on kvkXo) cfyepofjievr]? rrjs G(f)aLpas ovS' 
ortovv fievei popiov ri ydp dv dXr]V dvayKaZov rjv 

20 fji€V€LV, TJ hiaoTTaodaL ro ovvex^s avrrjs. dAA' 
on rovs ttoXovs oiovrai nva hvvap.iv €;)(6tv, ovOev 

^ TovTo Kal scrips! : Kai tovto libri. 
• (fcrrat Jaeger (cum Leon.): iveadai Whr'i. 

" Just as Odysseus' companions while seated in the ship 
open the bags containing the winds, and the ship is blown 
out of its course (Homer, Od. x. 46 ff.). 


paint him '^ ; for they make him emit the breath 
from his own hps. For whether one emits the 
breath gently or so strongly as to create the greatest 
gale (and the same is true if that which is thrown 
or pushed is something other than breath), it is 
necessary, first, that one should be supported upon 
one of one's own members, which is at rest, when one 
pushes, and secondly, that either this member itself 
or that of which it forms part, should remain still, 
resting upon something which is external to it. Now 
the man who tries to push the boat while he himself 
is in it and leaning upon it, naturally does not move 
the boat, because it is essential that that against 
wliich he is leaning should remain still ; but in 
this case that which he is trying to move and that 
against which he is leaning, is identical. If, on 
the other hand, he pushes or drags the boat from 
outside, he can move it ; for the ground is no part of 
the boat. 

III. The difficulty may be raised, whether, if some- 
thing moves the whole heaven, this motive power 
must be unmoved and be no part of the heaven nor 
in the heaven. For if it is moved itself and moves the 
heaven, it can only move it by being itself in contact 
with something that is immovable, and this can be no 
part of that which causes the movement ; or else, if 
that which causes the movement is from the first im- 
movable, it will be equally no part of that which is 
moved. And on this point at any rate they are quite 
right who say that, when the sphere is moved in a 
circle, no part of it whatsoever remains still ; for 
either the whole of it must remain still, or its continu- 
ity must be rent asunder. They are not right, how- 
ever, in holding that the poles possess a kind of force, 



9a ^ 

exovrag fieyedo? aAA' ovras eaxdra kol arty/xas', 

ov KaXcos. npog yap rco fn^hefxtav ovoiav elvai 
rcov TOLOVTOJV firjSevos, /cat KLvelaOai rrju fxlav 


25 TTOiovGiv. OTL fiev ovv e;)^et re Kal Trpos rrji^ oXr]v 
(j)VOLV ovTOJS cjGTrep rj yrj npo? to. ^a>a /cat ra 
KLVov/xeva 8t' avrcov, e/c rcov roiovrcuv av rt? 
Zia7TopriG€i€v. ol 3e jxvOlkcjs tov "ArXavra 
TTOLOVvres irrl rijg yrjg e^ovra rovs irohas So^auev 
av OLTTO StavoLag elpr^Kevai rov fxvdov, co? rovrov 
warrep hidpLerpov ovra /cat (JTpe(f)ovTa rov ovpavov 

80 rrepl rovs ttoXovs' rovro 8' av avfi^atvoL Kara 
Xoyov Sid ro rrjv yrjv jxeveiv. dXXd rocs ravra 
XeyovGLV dvayKalov (f)dvaL /xr^Sev etvat fiopLov 
avrrjv rov iravros. Trpos Se rovrois Set rr^v laxvv 
lad^eLV rov Kivovvros /cat rrjV rov fievovros. eon 
ydp ri ttXtjSos lo^vos /cat Swdfieajs /ca^' -^v fxevei 

85 rd fX€vov, wGTTep /cat /ca^' rjv klv€l ro klvovv /cat 
ecrrt ris dvaXoyla e^ dvdyK7]s, cjarrep rcov ivavricov 
KLV-qaecov, ovrco /cat rcov rjpefJLLcov. /cat at fiev 
'^'J taat dTTadels vtt* dXX-qXcov, Kparovvrai Se Kara 
rrjv VTrepox'^jV. StoTrep etr' "ArXas €Lre ri rotovrov 
ioriv erepov ro klvovv rcov ivros, ovSev jidXXov 
dvrepeiheiv Set rrjs piovrjs rjv rj yrj rvyxdvet fievovaa' 
'q KivrjO-qaeraL r) yrj 0,770 rov fieoov Kal e/c rov 

5 avrrjs rorrov. cLs ydp rd ihdovv (hdel, ovrco rd 
(hdovfJLevov (hOelraiy Kal dfiOLcos Kar lgxvv, klv€l 

* i.e. their limbs. We should, however, perhaps read 5t' 
avTuJi/ "the things which move of themselves": Leon, 
renders "ea quae per se moventur." 


since they have no magnitude and are only ex- 
tremities and points. For besides the fact that 
nothing of this kind has any substance, it is also im- 
possible for a single movement to be started by a dual 
agency ; and they represent the poles as two. From 
these considerations one may hazard the suggestion 
that there is something which stands in the same 
relation to Nature as a whole as the earth stands to 
the animals and the things which are moved through 

Now those who in the fable represent Atlas as hav- 
ing his feet planted upon the earth would seem to 
have shown sense in the story which they tell, since 
they make him as it were a radius, twisting the 
heaven about the poles ; it would be a logical account, 
since the earth remains still. But those who hold 
this view must declare that the earth is no part of the 
universe ; and, further, the force of that which causes 
the motion and the force of that which remains still 
must be equal. For there must be a certain amount 
of force and strength in virtue of which that which 
remains still remains still, just as there is a force in 
virtue of which that which causes motion causes 
motion ; and there is of necessity a similar proportion 
between absences of motion as there is between 
opposite motions, and equal forces are unaffected by 
one another, but are overmastered by a superiority. 
Therefore Atlas, or whatever else it is of like kind 
within that causes motion, must not exert any pressure 
which is too strong for the equihbrium of the earth ; 
or else the earth will be moved away from the centre 
and her proper place. For as that which pushes 
pushes, so that which is pushed is pushed, and in 
exact proportion to the force exerted ; but it creates 



699 b 

Se TO rjpefiovv rrpajrov, cjore ixdXXov /cat TrXeLCOV 

rj LG^vs rj ofjLOLa /cat tcrr] rrjg rjpejjLLas. (LoravTOJS 
Se /cat TTJs^ rod Ktvovfievov /xeV, {jltj klvovvtos Se. 
rocravT-qp ovv hei'^aei rrjv BvvajJLLV etvat tt^s" yrj? 

iv TO) rjp€fJL€LV 6uT]V 6 T€ TTO-S OVpaVOS ^X^^ '^^^ 

10 ro KLvovv avTOv. el Se rovro dSvparoVy dbvyarov 
/cat TO KLveLGdat rov ovpavov vtto tlvos tolovtov 
ra>v ivTos. 


rod ovpavov pLopLcov, rjv cLs ovaav ot/cetav rot? 
elprjpilvois eTTiGKe^aLT dv rig. idv yap rts" vnep- 
PdXXj) rfj Svvdfxei rrjs KLVijcrecog rrjv rrjs yrjs 

15 Type/xtW, SrjXov on KivrjoeL avrrjv 0,770 rov fieaov. 
/cat rj LGXvs 8' d(/)' rjg avrrj rj Svvapag, on ovk 
dneLpos, (fyavepov ovhk yap r] yrj drreipoSy ojor 
ovhe TO ^dpos avrrj?. irrel Se ro dSvvarov Xlyerai 
TrXeovaxdj? {ov yap (haavrws rrjv re ^ojvrjv d^vvarov 
(jyajxev elvai opadrjvat /cat rovs eirl rrjs aeXrjvrjs 

20 v(f)* rjjiajv ro fiev yap e^ dvdyKrjs, ro Se 7re<^u/c6s 
opdadai OVK ocfyOrjoerai) , rov S' ovpavov d(f)daprov 
etvau /cat dStaAurov olojxeOa jxkv e^ dvdyKrjs etvaL, 
GVfjL^aiveL Se /card rovrov rov Aoyov ovk e^ dvdyKrjS' 
7Te(f)VKe yap /cat evSex^rai etvau Kivrjoriv fiel^oj 
/cat d</>' rjs rjpefiel rj yrj /cat d(^' rjs Kivovvrat ro 

25 TTvp /cat TO dvoj crajjia. el fiev ovv elalv at vrrep- 
exovaai KLvrjoeis, hiaXvdrjoerai ravra vn dXXrjXcov. 

1 T^j PS: 7? Y: aJE. 

* i.e. its central position in the universe. 

^ i.e. the region between the air and the moon (Meteor. 
340 b 6 if.). 


motion in that which is first at rest, so that the force 
exerted is greater than the immobility rather than 
similar and equal to it, and likewise greater than the 
force of that which is moved but does not create 
movement. Therefore the power of the earth in its 
immobility will necessarily be as great as that pos- 
sessed by the whole heaven and that which sets it in 
motion. If, however, this is impossible, the move- 
ment of the heaven by any such force within it is also 

IV. A problem also arises about the movements 
of the parts of the heaven, which might well be dis- 
cussed, since it is closely connected with what has 
been said above. If one were to overmaster the im- 
mobihty of the earth by the power of motion, one will 
obviously move it away from the centre. ° Moreover 
it is clear that the force from which this power is de- 
rived is not infinite ; for the earth is not infinite, and 
so its weight is not infinite either. Now^ the w^ord 
" impossible " is used in several senses (we are using 
it in different senses when we say that it is impossible 
to see a sound, and when we say that it is impossible 
for us to see the men in the moon ; for the former is 
of necessity invisible, the latter are of such a nature 
as to be seen but will never be seen by us), but w^e 
hold that the heaven is of necessity impossible to 
destroy and dissolve, whereas according to our present 
argument it is not necessarily so ; for it is within the 
nature of things and the bounds of possibility that a 
motive force should exist greater both than that 
which causes the earth to be at rest and than that 
which causes the fire and upper body ^ to move. 
If, therefore, the overpowering motive forces exist, 
these will be dissolved by one another; but if they 

p2 451 


699 b 

el 8e fJLTj elal /xeV, ivSex^rai 8' elvai [aTreipov yap 
ovK evSe;^eTat 8ta ro fi-qSev crco/xa eVSe;^ea^at 
a7T€Lpov elvai), eVSe;^otr* av' ScaXvOrjvaL rov ovpavov. 
TL yap KUjXvei tovto avjJL^rjvai, etVep jjlt] dSuvarov ; 
'^*^ OVK dSvvarov 8e, et jLt')7 ravriKeiiievov dvayKalov. 
dXXd 776/36 /xev TTjs diTopias ravrrjs 'irepog eurcu 

*Apa he Set aKLvqrov n etvai /cat rfpefjiovv e^co 
rov KLvovjievov, pLrjSev ov eKeivov pLopioVy t) ov ; 


VTToipx^i'^ dvayKalov; taajs yap dv So^eiev aToirov 

35 elvaiy el rq dpxr] ttjs Kivqaeajs ivTos. 8to So^eiev 

av ToZs ovTCDS VTToXafjL^dvovaLV ev elprjod ai 'Ofi-qpo)' 

dXX* OVK dv epvuaiT ef ovpavoOev TreStovSe 

700a TjTJV^ VTTaTOV TTaVTCOV , OuS' €t /XaAa TToXXd KafJLOLTe' 

iravTes 8' e^aTTTeode deol TTauai re ^eatvat. 

TO ydp oXcos dKiv7]Tov VTT* ovhevos ivSex^Tat 
KLVTjdrjvai. 66 ev Auerat /cat tJ TraAat Ae;^^eto-a 
dTTOpia, TTOTepov evSex^rai rj ovk evhex^rai 8ta- 
5 Xvdrjvai Trjv tov ovpavov GvaTaauv, el ef dKivrjrov 
rjprrjTaL dpX'rjS' 

*E7rt 8e TCtJv l,a)<jjv ov jjlovov to ovtcjos dKcvrjTOV 
Set VTTapx^i^v, dXXd /cat ev avTols toXs KLVovfievois 

* direipoi'] sc. Klvrjcriv. The argument is as follows: these 
overpowering motive forces might exist and be dissolved by 
one another, because if they can be dissolved, they are not 
infinite, and the reason why they are not infinite is that they 
act upon what is finite, and the infinite cannot act on the 
finite (7> caelo, 274 b 23 flF.). 

•' It is discussed in the Physics and De caelo. 


do not really exist, but there is a possibility of 
their existing (for an infinite motive force " is impos- 
sible because an infinite body is also impossible), 
it would be possible for the heaven to be dissolved. 
For what is there to prevent this happening if it 
is not impossible ? And it is not impossible, unless 
the opposite proposition is inevitable. But let us 
leave the discussion of this question for another 

Must there, then, or must there not, be something 
immovable and at rest outside that which is moved 
and forming no part of it ? And must this be true 
also of the universe ? For it would perhaps seem 
strange if the origin of motion were inside. And so 
to those who hold this view Homer's words w^ould 
seem appropriate : 

Nay, ye could never pull down to the earth from the 

summit of heaven, 
Zeus, the highest of all, no, not if ye toiled to the utmost. 
Come, ye gods and ye goddesses all, set your hands to 

the hawsers.* 

For that which is entirely immovable cannot be 
moved by anything. And it is here that we must 
look for the solution of the problem stated some time 
ago, namely, whether it is possible or impossible for 
the composition of the heaven to be dissolved, seeing 
that it depends upon an origin which is immovable. 

Now in the animals there must exist not only that 
which is immovable in this sense,** but there must 
also be something immovable in the actual things 
which move from place to place and which themselves 

<= Iliad viii. 20-22. The lines are quoted in the wrong 
order and the textits receptus reads iJ.-qaTwp' for Travruv. 

^ i.e. something immovable and at rest which is outside 
that which is moved and forms no part of it (c/. 699 b 32). 



Kara tottov oaa klv€l avra avra. Set yap avrov 
TO fjLev rjpejielv ro 8e KLvetaOai, rrpog o (XTrcpetSo- 

-0 puevov TO KLvovpiei'OV KLvrj(j€Tai, olov av tl KLvfj 
ra)v pLOpLOJV aTrepetSerat yap OaTC pov ojg irpos 
pLevov OaTepov. rrepl Se tcov difivxcov oaa KLvetTac 
OiTTO pi] (J€i€v av Tig, TTorepov airavr^ e;)(€t iv iavTols 
/cat TO rjpepLovv Kal to klvovv, Kal rrpos tcov 
e^O) Tt rjpepiovvTOJV dTrepeiSeadaL dvdyKrj Kal 
ravra, 7) dhvvaTOV, otov TTvp tj yrjv t] tojv difivx^iv 

16 Tt, dAA'^ u^' (Lv TavTa KiveiTai TrpcjTCjjv. Trdvra 
yap V7T* dXkov KiveiTai Ta dipyxct-, dpx^j Sc TrdvTcov 
TOJV ovTOJS KLVovpievojv rd aura aura KivovvTa, 


yap ToiavTa Trdvra dvdyKJ) Kal iv avToZs ^X^^^ 
TO TjpepLovv, Kal e^oj rrpog o o-TrepetaeTat. el Se 
20 Tt iarlv dvojTepco Kal tt/jcutw? klvovv, dSrjXov, 
Kal aAAos" Xoyos irepl ttJs" ToiavTJ^s dpx^jS' '^d 
Se ^cpa ocra KLveiTai, Trdvra Trpos rd e^o) dnep- 
etSd/xeva KivelraL, Kal dvaTTveovra Kal eKTTveovra. 
ovSev yap hia^epei piiya pZipai ^dpos tj puKpov, 

OTT€p TTOLOVGIV ol TTTVOVTeS Kal ^rjrrovT€s Kai OL 

V. Tlorepov S' iv rep avro klvovvtl Kara tottov 
fxovcp Set Tt p,€V€Lv, 7] Kal iv Tw dWoiovpiivcp avrcp 
V(f)* avrov Kal av^avopiivcp ; rrepl Se yeviaeojs 
TTJs ii dpxrjs Kal cjydopdg aAAo? Xoyog' el ydp icrriv 

1 dXX' Jaeger : dXXa P : AXX' ESY. 


move themselves. For while one part of the animal 
must be in motion, another part must be at rest, 
supported upon which that will be moved which 
is moved, if, for example, it moves one of its parts ; 
for one part rests on another part in virtue of the 
fact that the latter is at rest. 

But regarding inanimate things which are moved, 
one might raise the question whether they all possess 
in themselves both that wliich is at rest and that which 
creates movement, and whether they too must be 
supported by something external which is at rest. 
Or is this impossible — for example, in the case of 
fire or earth or any inanimate thing — but motion is 
due to the primary causes by which these are moved ? 
For all inanimate things are moved by something else, 
and the origin of all the things that are thus moved is 
the things that move themselves. Among things of 
this class we have already dealt \\'ith animals ; for all 
such things must necessarily have within themselves 
that which is at rest and something outside them on 
which they are to support themselves. But whether 
there is something higher and primary which moves 
them is uncertain, and the question of such an origin 
of movement is a matter for separate discussion. But 
animals which move all do so supported upon things 
outside themselves, as also when they draw their 
breath in and out. For it makes no difference whether 
the}" propel a great or a small weight, as those do who 
spit and cough, and breathe in and out. 

V. But is it only in that which moves itself in 
respect of place that something must remain at rest, 
or is this also true of that in which alteration is 
caused by its own agency and in that which grows ? 
The question of original coming into being and 



7]V7T€p (pafiev TTpcoTT] Kivif]GLs, yeveaeojs /cat (puopas 

30 avTT] air La av eirj, /cat rcbv dXXcov 8e KLVi^aeajv taojs 
TraGOJV. a)G7r€p 8' iv rco oXco, /cat eV rep ^cp(p 
KLvrjois TTpwrrj avrrj, orav reXecodfj- ware /cat 
av^-qaeojs, eu ttote ytVerat, avro avrcp oltlov /cat 
dXXoLojoreojg, el Se fJLij, ovk dvdyKTj. at Sc Trpcurat 
av^T^creLS /cat dAAotcoaets' i57r' aAAou yivovrai /cat 

35 8t* erepojv yeveaecog 8e /cat cf)6opds ovSajuLcos oTov 

700 br€ auTO atrtor eti^at avrcp ovSev. Trpovirdpx^^v 

yap Set ro kivovv rov KLvovfievov /cat ro yevvcjv 

rod yevvajfievov avro 8' avrov rrporepov ovhiv 

ear IV. 

VI. Hept /Ltev ouv ifjvxrj?, etre KiveZrai ri fjut], 
5 /cat el Kivelraiy ttcj? Kivelrai, rrporepov etpiqrai ev 
Tois SicopLGfievoL? rrepl avrr^s. iirel 8e rd dipvxa 
rrdvra KiveZrai vcf)* irepov, rrepl 8e^ rod rrpwrov 
KLVovfievov /cat aet Kivovjxivov, riva rpoirov Kivelraiy 
/cat Traps' KiveZ ro rrpcorov klvovv, hiaypLorai rrporepov 
iv rots rrepl rrjg TrpcLrrj^ (/)LXoGO(f)Las, Xolttov 8* 

10 iarl BeojprjGai nco? rj ip^XV Kivei ro acofia, /cat 
rts dpx^] rrjs rod t,cpov KLvijoecog. rwv yap dXXa>v 
TTapd rrjv rov oXov klvt^glv rd efjiifjvxci atria rrjg 
KLvqGeoJS, oGa fir] Kivelrai ott^ dXXrjXwv 8ta ro 
TTpoGKOTTreiv dXXriXoi£. Sto /cat iripas exovoiv 
avrojv Trdaai at KLvt]G€Ls' /cat yap /cat at rcjv 

15 ipufjvxcDV. rrdvra ydp rd ^wa /cat KLveZ /cat 
KLveZrac evcKd nvos, coore rovr^ eanv avroZs 
TrdGrjs rrjs Kivrjoeajs nepas, ro ov eveKa. opdjjjiev 
1 5^ ES : fJLiv Y. 

* tovt4(Xtiv . . . OVK elvai tl tCjv dWoiovfi^yuv Kal 
av^avofiiviov v(f> avrdv -fipe/iovv (Mich.). 

* i.e. the Metaphysics. 


corruption is a different one ; for if there is, as we 
assert, a primary movement, this would be the cause 
of coming into being and wasting away, and per- 
haps of all the other movements as well. And as in 
the universe, so in the animal, this is primary motion, 
when the animal comes to perfection ; so that it is 
itself the cause of its own growth, if this ever takes 
place, and of any alteration which occurs ; otherwise 
it is not necessary that something should remain at 
rest." But the first growth and alteration occur 
through another's agency and by other means, and 
nothing can in any way be itself the cause of its own 
coming into being and wasting away ; for that \vhich 
moves must be prior to that which is moved, and that 
which begets to that which is begotten, and nothing 
is prior to itself. 

VI. Now whether soul is moved or not, and if 
it is moved, how it is moved, has already been 
discussed in our treatise On Soul. But since all 
inanimate things are moved by something else — and 
how that which is primarily and eternally moved is 
moved, and how the prime mover moves it, has been 
already set forth in our work on First Philosophy ^ — 
it remains to inquire how the soul moves the body 
and what is the origin of movement in an animal. 
For, if we exclude the movement of the universe, 
animate things are the cause of movement in every- 
thing else, except in things which are moved by one 
another through coming into coUision with one 
another. Therefore all their movements have a 
limit ; for the movements of animate things have a 
limit. For all animals move and are moved with 
some object, and so this, namely their object, is the 
limit of all their movement. Now we see that the 



700 b 

Se ra Kivovvra to t,coov hidvoiav /cat <f)avTaalav 

Kal TrpoalpecTLv /cat ^ovXiquiv /cat €7TLdv[iiav. ravra 
Se TTOLvra avdyerai els vovv /cat ope^iv. /cat yap 

20 7) (f)avraaLa /cat rj aladrjcns ttjv avrrjv rep vcp x^P^^ 
€Xov(JLV KpiTLKa ydp Trdvra, hia^ipovGi 8e Kara 
rds elprjfievas ev aAAotj hiacjiopds. ^ovXtjols Se 
/cat dvpLOs /cat eVt^u/xta Trdvra ope^Ls, rj Se vrpo- 
atpeorts" /cotvor Stavotas" /cat ope^eojs' cjare KtveZ 
TrpaJTOv ro opeKrov /cat to Stai'OT^Toi^. ou Trav 

25 Se TO StaroT^Tov, aAAa to tojv TrpaKrcov reXos. 
8to ro roiovrov ian rwv dyaOojv ro klvovv, dAA* 
ov rrav ro KaXov rj ydp eVe/ca rovrov d'AAo, /cat 
^ riXos icrrl tcuv dAAou Ttyos" eve/ca ovrcoVy ravrrj 
KLV€L. Set Se ridevai /cat to (j^aivopievov dyadov 
dyadov )(ojp^^ '^X^^^> ^'^^ '^^ 'J^Su* <j)aiv6p.€vov ydp 

80 eonv dyadov. ojare SrjXov on eon fiev fj opLoicJs 
KLveXrai ro del klvovjjl€vov vtto rod del KLVovvros 
/cat rojv t,a)0)v eKaorov, eon 8' fj dXXojs, 8to /cat 
rd /xei^ det Kivelrai, r) 8e tcov t^cpojv Kiviqais €;\;et 
Tvepas. ro 8e dt8toP' /caAdi^, /cat to dAT^^dis /cat 
rrpajrojs dyadov /cat jLt'37 ttotc fxev TTore Se jlitJ, 

86 deiorepov /cat rijxicorepov r) 6oo"t* etP'at Tvporepov^ n"^. 
To jLtev ow rrpcorov ov Kivovp,evov /ctvet, t^ 8' 

701 a ope^Ls Kal ro opeKriKov Kivovpievov Kivel. ro he 

reXevraZov rcov KLvovjJLevcDV ovk dvdyKTj Kivelv 
ovbev. (f)av€p6v 8' e/c toutoji^ /cat OTt evXoyws 

^ irpbrepop ESY : irphs ^repov P. 
2 Ti add. Jaeger. 

" De anima, iii. 427 b 14 flF. 



tilings which move the animal are intellect, imagina- 
tion, purpose, wish and appetite. Now all these can 
be referred to mind and desire. For imagination 
and sensation cover the same ground as the mind 
(since they all exercise judgement) though they 
differ in certain aspects as has been defined else- 
where.** But will, temper, and appetite are all 
forms of desire, while purpose partakes both of 
intellect and of desire. So the objects of desire and 
intellect first set up movement — not, however, every 
object of intellect, but only the end in the sphere of 
action. So amongst good things it is the good in the 
sphere of action that sets up movement, and not any 
and every good ; for it sets up movement only in so 
far as it is the motive of something else or the end 
of something which has something else as its object. 
And we must lay dow^n the principle that the apparent 
good can take the place of a real good, and so can the 
pleasant, for it is an apparent good. So that it is 
clear that in one respect that which is eternally 
moved by the eternal mover, and the individual 
animal, are moved in a similar manner, but that in 
another respect they are moved differently ; and so, 
while other things move eternally, animal movement 
has a limit. Now the eternally beautiful and that 
which is truly and primarily good, and not at one 
moment good and at another not good, is too divine 
and precious to have anything prior to it. 

The prime mover, then, moves without itself being 
moved, but desire and the desiderative faculty set 
up movement while being themselves moved. But 
it is not necessary that the last of a series of things 
which are moved should move anything ; and from 
this it is clear that it is only reasonable that pro- 



-^ (popa TeAeurata row ytvofievcov ev tols klvov- 
fievoLS^ • KLvelTat yap /cat TropGveraL to t,a)ov ope^et 

5 7) 7rpoaLpe(T€L, dXXoLCoOevros nvos Kara t7]v at- 
oQrjGLV T] Tr]v ^avraaiav . 

VII. ricDs" Se vocjv ore fikv TrpdrreL ore 8' ov 
TTpoLTrei, Kol KLveirai, ore 8' ov KiveZrai; eot/ce 
irapaTrX-qaicos cru/x^atVetv kol Trepl rcov aKLvqrajv 
SiavoovfievoLS Kal <jvX\oyLl,o[Ji€VOLS . aAA' e/cet fxev 

10 Oecoprjfxa to reAo? (orav yap rds Svo TTpordoeis 
vo^GT], TO o-u,(X7repaCT/xa ivorjae Kal avvedrjKev), 
ivTavOa 8* iK rcov Svo TTpoTacrecov to orufjiTTepacFfia 
ylveTai rj irpd^is, olov oTav vo-qarj ort Travrl ^a- 
Stcrreov dvOpcoTTO), avros 8' avSpcmros, ^a8t^et 
€vde(i)s, oiv 8' OTL ovSevl ^aSiGTeov vvv dvdpcona), 

16 avros 8* dvO pcjTTOS , evOvs T^pe/xet* Kal TavTa a/x^a> 
7TpdrT€L, dv iiTj TL KcoXvYj Tj dvayKdl,r]. TTOirfTeov 
fjLoi dyaOov, oiKia 8' dyadov 7tol€l OLKiav evOvs. 
aKendafiaTOs 8eo/xat, Ifidrtov Se GKeTracrfxa' L/xarLov 
8eo/xat. ov 8eo jitat, TTOir^Teov Ifjiariov 8eo/xaf 

20 Ij^idTiov 7TOL7]reov. Kal to crvpLTTepacxjjLa, to IfidTiov 
TTOLTjTeoVy Trpd^is ioTiv. TTpaTTei 8' 0,77' dpxrj?. 
el IfidTLOV ecrrat, dvdyKT] To8e irpchTOV, el he To8e, 
Tohe' Kal Tovro irpdrTei evdv?. otl p,ev ovv r] 
TTpd^LS TO GVfxnepaoiJLa, (jyavepov at 8e TrpordaeLg 
at 7TOL7]TtKal Sid Svo elSwv yivovTai, 8ta re tov 

25 dyadov Kal hid tov hvvaTOV. 

"Q.airep he tojv epcorcovTOJV evioi, ovra> rrfv erepav 

^ Kivovfi^pois Jaeger: 7t7J'OAi^»'ois libri. 

« i.e. the objects of science ; cf. An. Post. 71 b 18 ff. 


gression should be the last thing to happen in things 
that are moved, since the animal is moved and walks 
from desire or purpose, when some alteration has been 
caused as the result of sensation or imagination. 

VII. But why is it that thought sometimes results 
in action and sometimes does not, sometimes in 
movement and sometimes not ? Apparently the 
same kind of thing happens as when one thinks and 
forms an inference about immovable objects. <* But 
in the latter case, the end is speculation (for when you 
have conceived the two premisses, you immediately 
conceive and infer the conclusion) ; but in the former 
case the conclusion drawn from the two premisses 
becomes the action. For example, when you conceive 
that every man ought to walk and you yourself are a 
man, you immediately walk ; or if you conceive that 
on a particular occasion no man ought to walk, and 
you yourself are a man, you immediately remain at 
rest. In both instances action follows unless there is 
some hindrance or compulsion. Again, I ought to 
create a good, and a house is a good, I immediately 
create a house. Again, I need a covering, and a 
cloak is a covering, I need a cloak. \Miat I need I 
ought to make ; I need a cloak, I ought to make 
a cloak. And the conclusion " I ought to make a 
cloak " is an action. The action results from the 
beginning of the train of thought. If there is to be 
a cloak, such and such a thing is necessary, if this 
thing then something else ; and one immediately 
acts accordingly. That the action is the conclusion is 
quite clear ; but the premisses which lead to the doing 
of something are of two kinds, through the good and 
through the possible. 

And as those sometimes do who are eliciting con- 



irporaoiv rrjv hrjXrjv ouS' tj Sidvoia i(f)Lard(ja GKOTreZ 
ovSdv olov €L TO ^aoit^etv dyaOov dvOpojirco, on 
avTos dvdpojTTos, ovK ivhiarpl^eL. ^i6 /cat oaa fxrj 
XoyLodfjuevoL TTpdrro}xeVy raxv TTpdrropLev. orav yap 
ivepyrjGr) t) rfj alodria<Ei npos to ov ere/ca rj rfj 

30 ^avraoia t) rep vo), ov opeyerau, evOvs ttoleX' dvr* 
epcoT'-qaeco? yap rj vo-rjoecos r] rrjs dpe^eojs yiverai iv- 
Ipyeia. TToriov fiot, rj emOvpiia Xeyec- roSl Se ttotov, 
Tj alcrOrjGis elrrev rj rj (fiavraoia rj 6 vovs' evOvs Trivei. 
ovrcxjs P'€v ovi^ eTTL TO Kivelodai /cat 77parrety to, 
t,cx)a opfjLcoGL, Trjs fJi€v iaxdTrjs atrta? tov KiveladaL 

35 ope^ecos ovorjs, TavTrjs Se yivopievrjs rj St* alodrjueajs 

rj Sta <f)avTaGLa? /cat vo-qcrecos. twv S* opeyopblvcov 

TrpdTT€Lv ra fxev St' emdvpLLav r) Ovjjlov to. Se St* 

701 b ope^iv t) ^ovXrjULV Ta fxev ttolovgl, Ta Se rrpdTTOvcriv. 

"Q.G-nep Se ra avTopLaTa /ctvetrat jiiKpds Kivrjoeajg 

yivojxevrjs, Xvofievcov tcov UTpe^Xcov /cat Kpovovcrojv^ 

dAATJAas" [ra? OTpe^Xas],^ /cat to d/xaftov, orrep 

b (roy 6)(ovp.evov avTO Kivei el? evdv, /cat TrdXiv 

kvkXco KLveiTai tco dvlaovs ^X^^^ tovs Tpoxovs 

(d yap iXdTTOJv oioirep KevTpov ytVerat, Kaddnep 

iv TOLs /cuAtVSpots"), ovTOJ /cat TO. ^(pa KivelTai. 

ex^f' ydp opyava rotaOra Tiqv re rcov vevpcov 

(f)VGLV /cat Trjv tCjv ogtc^v, to, fiev ws eKeZ tcl 

^ Kpovova-Qv scrips! (Leon, renders laxatis seque mutuo im- 
pellentihus vertehris) : Kpovbvrwv libri. 

■ rds crrp^/SXas seclusi. ^ rh addidi. 

* For this technical use of ipwrav cf. An. Prior. 24- a 24. 

* By the removal of the pejrs {^u\a), cf. below, 701 b 9, 10. 

* The context seems to show that the toy-carriage was 
on an axle which coupled two wheels of unequal diameter. 
There is, however, no evidence for the existence of such toy- 
carriages in antiquity. 



elusions by questioning," so here the mind does not 
stop and consider at all one of the two premisses, 
namely, the obvious one ; for example, if walking is 
good for a man, one does not waste time over the pre- 
miss " I am myself a man." Hence such things as we 
do without calculation, Ave do quickly. For when a 
man acts for the object which he has in view from 
either perception or imagination or thought, he 
immediately does what he desires ; the carrying out 
of his desire takes the place of inquiry or thought. 
My appetite says, I must drink ; this is drink, says 
sensation or imagination or thought, and one 
immediately drinks. It is in this manner that animals 
are impelled to move and act, the final cause of their 
movement being desire ; and this comes into being 
through either sensation or imagination and thought. 
And things which desire to act, at one time create 
something, and at another act, by reason either of 
appetite or of passion, or else through desire or wish. 
The movement of animals resembles that of 
marionettes which move as the result of a small 
movement, when the strings are released ^ and strike 
one another ; or a toy-carriage which the child that 
is riding upon it himself sets in motion in a straight 
direction, and which afterwards moves in a circle 
because its wheels are unequal, for the smaller wheel 
acts as a centre," as happens also in the cylinders.'* 
Animals have similar parts in their organs, namely, 
the growth of their sinews and bones, the latter cor- 
responding to the pegs in the marionettes and the 

<* The marionettes seem to have been worked by means of 
cylinders round which weighted strings were wound, the 
cylinders being set in motion by the removal of pegs. 



fuAa Kal 6 uihiipos, ra 8e vevpa a>s" at orpi^Xai' 

10 c5v XvofievcDv Kal avi€jiivojv Kivovvrai. iv fxev 
ovv rots' avTOfxarois Kal rot? djjLa^LOLs ovk eariv 
dXXoicooLs, incl el iyivovTO iXdrrovs ol ivrog 
rpoxol Kal rrdXiv pieLt,ovs, Kav kvkXco to avro 
iKiveiTO' iv Se rep ^coco Swarat to avro Kal 
fjieX^ov Kal eXarrov yiveoOai Kal ra G)(rjp,aTa pcera- 

15 ^dXXeiv, av^avopevojv rcov pLopiojv hid deppLorrjTa 
Kal TTaXiv (jvGreXXopiivojv hid ifjv^iv Kal dXXoiov- 
pievajv. diXXoiovcn 8' at ^avraoiai /cat at alodrjueis 
Kal at evvoiai. at /xe^' ydp aludiqueis evOvs vtt- 
dpxovGiv dXXoiojGeig riveg ovcrai, rj he ^avraoia /cat 
7] voTjOis TTjv rcov TTpaypidrojv exovcri hvvapiiv rpo- 

20 TTov ydp TLva TO ethos to voovfievov ro rod OeppLov 
7] ipvxpov ^ 'qheos ^ (fyo^epov roiovrov rvyxdvei 
ov oiov nep Kal rwv rrpaypidrajv eKaarov, hio Kal 
(f>piTTovcn Kal (f)o^ovi'Tai voTjoravres p.6vov. ravra 
he Trdvra TrdOrj Kal dXXoicoaeis eluiv. dXXoiov- 
fxevcov 8' iv rep GojpLari rd pev piei^co rd 8* iXdrrcj 

25 yiverai. on he puKpd piera^oXr] yivoptevr] iv dpxfj 
pieydXas Kal TToXXdg TToiel hia<j)opds diroOev, ovk 
dhrjXov oiov rod o'iaKos aKapiaZov ri piediGrapLevov 
ttoXXt] Tj rrjg TTpcopas yiverai pierdaraGis. en he 
Kard Oeppiorrjra -^ i/jv^iv t) /car* aAAo n roiovrov 
TTados orav yevrjrai aXXoiwuig Trepl rr]v Kaphiav, 

80 /cat iv ravrrj Kard pieyedos iv dvaiaO-qrcp piopicp, 
TToXXrjv TTOiei rod acopiaros hia(f)opdv ipvdr^piaori 
Kal (hxpdrrjGi Kal (f)piKais Kal rpopiois Kal rot? 
rovrojv ivavrioig. 

VIII. *Apxr) piev ovv, axJTTep elp-qrai, rrjs 

" The reference is probably to some part of the toy- 


iron,** while the sinews correspond to the strings, the 
setting free and loosening of which causes the move- 
ment. In the marionettes and the toy-carriages no 
alteration takes place, though, if the inner wheels 
were to become smaller and then again larger, the 
same circular movement would take place. In the 
animal, however, the same part can become both 
greater and smaller and change its form, the mem- 
bers increasing through heat and contracting again 
through cold and thus altering. Alteration is 
caused by imagination and sensations and thoughts. 
For sensations are from the first a kind of altera- 
tion, and imagination and thought have the effect 
of the objects which they present ; for in a way the 
idea conceived — of hot or cold or pleasant or terrible — 
is really of the same kind as an object possessing one 
of these qualities, and so we shudder and feel fear 
simply by conceiving an idea ; and all these affec- 
tions are alterations, and when an alteration takes 
place in the body some parts become larger, others 
smaller. Now it is clear that a small change taking 
place in an origin of movement ^ causes great and 
numerous changes at a distance ; just as, if the rudder 
of a boat is moved to an infinitesimal extent, the 
change resulting in the position of the bows is con- 
siderable. Furthermore, when, owing to heat or 
cold or a similar affection, an alteration is caused 
in the region of the heart — and even in an imper- 
ceptibly small part of it — it gives rise to a consider- 
able change in the body, causing blushing or pallor 
or shuddering or trembling or the opposites of these. 
VIII. The origin, then, of movement, as has already 

" i.e. here, the heart, cf. below, 701 b 30 ; see also note on 
698 bl. 



701b , , , . . <. , . , 


i^ OLvdyKT]? 8' oLKoXovdeX rfj voTJcrec /cat rfj (f)avra<jla 

35 avTOJV OepfJLOT'qg Kal ipv^ig. ro fxev yap Xvirrfpov 

(fyevKTOv, TO 8' rjSu Slojktov (aAAa Xavddvei nepl 

TO, piLKpd TOVTO GVpL^OLVOv) , eCTTL 8e TO. Xv7Tr]pd 

702 a Kal Tjhea Trdvra cr;^e8ov jLtera ifjv^eco? Ttvog /cat 
depjioT'qTOS. TOVTO 8e hr\Xov eK rajv TraOrj jiaT cov. 
ddpprj yap /cat cf)6^oL /cat dcfypoSiGtacriiol /cat rdXXa 
TO, CTo^/xart/ca XvTTiqpd /cat 9^8ea ra pikv /caret fxopiov 
{jLeTOL OeppiOTTfTos ri i/jv^ecjg Igti, to, Se /ca^* oXov 
^ TO Gcbfxa' fJLvrjp^ai Se /cat iXTrlSes, olov elSwXoL? 

Xp(JOpL€VaL Tols TOiOVTOLS, 6t€ fieV TjTTOV 6t€ 8e 

pidXXov atrtat TCJov avTOJV elalv. ooot euAoya>s" 
r\hy] 87^/xtoupyetTat ra Ivtos /cat ra rcepX Tas dpyas 
Tojv opyavLKcov pLopiajv /xera^aAAoyra e/c TreTrrjyoTOJv 
10 z5y/oa /cat c^ vypojv TreTrr^yora /cat /xaAa/cd /cat 
(jKXrjpd i^ dXXTJXojv. tovtojv 8e crvfxpaLvovTOJV 


rroirfTLKOv TOLavTTjv e^ovTcuv ttjv (jivaiv olav ttoX- 
Xa^ov elpiJKafxev, orroTav Gvp,^fi coot^ elvai to 


15 avTCJv eKdTepov tcov ev rw Xoycp, ev9vs to fiev 
TTOtet TO 8e Trdax^i" Sta tovto 8' dfia ojs etTretv 
i^oet OTL TTopevTeov Kal Tropeuerat, av fJL'^ tl ipL- 
ttoSl^tj €Tepov. TO, fiev yap opyaviKa p-^pr] irapa- 
GK€vd^€i iTTLTT^SeLcog TO, TrdOrj , rj 8' ope^Lg to. 
Trddrjy rrjv 8' ope^Lv tj (f^avrauia' avTTj Se ytVerat 
iq Sta vorjoeojs ■q St' alad-qaeojs . dp,a Se /cat raxv 


dXXrjXa elvat ttjv (jiVGiv. 

^ rh add. Bonitz. 


been said, is the object of pursuit or avoidance in the 
sphere of action, and heat and cold necessarily follow 
the thought and imagination of these objects. For 
what is painful is avoided, and what is pleasant is 
pursued. We do not, it is true, notice the effect of 
this in the minute parts of the body ; but practically 
anything painful or pleasant is accompanied by some 
degree of chilling or heating. This is clear from the 
effects produced. Reckless daring, terrors, sexual 
emotions and the other bodily affections, both pain- 
ful and pleasant, are accompanied by heating or 
chilling, either local or throughout the body. Re- 
collections too and anticipations, employing, as it 
were, the images of such feelings, are to a greater or 
less degree the cause of the same effects. So it is 
w^th good reason that the inner portions of the body 
and those which are situated near the origins of the 
motion of the organic parts are created as they are, 
changing as they do from solid to liquid and from 
liquid to solid and from soft to hard and vice versa. 
Since, then, these processes occur in this way, and since, 
moreover, the passive and the active principles have 
the nature which we have frequently ascribed to them, 
whenever it so happens that the one is active and the 
other passive and neither fails to fulfil its definition, 
immediately the one acts and the other is acted upon. 
So a man thinks he ought to go, and goes, practically 
at the same time, unless something else hinders him. 
For the affections fittingly prepare the organic parts, 
the desire prepares the affections, and the imagina- 
tion prepares the desire, while the imagination is due 
to thought or sensation. The process is simultaneous 
and quick, because the active and the passive are by 
nature closely interrelated. 



702a ^ ^ , .. , , -, V 

1 o oe KLVovv -npajTov to L,ojov avayKJ) euvat ev rivi 
o-PXfi- V ^^ KafjLTTrj on fxev icrrt rov fiev dpxr) rov 
he reAeuT-)], eiprjrai. 8to kol ecrrt /xev co? eVt, eart 
8* o)? Sucre ;^p7^Tat 7^ (f)vuis avrfj. orav yap Kivrjrai 

25 ivrevdev, avdyKiq ro fiev rjpefjieLV rcbv arjfieLCJV ra>v 
iaxoLTCov, TO Se KLveTadai' otl yap jrpos -qpe/xovu 8et 
dTTepeiheudai to klvovv, eipiqTai rrpoTepov. KLveZTai 
fxev ovv /cat ov Ktvel to eaxoLTOV tov ^pax^ovog, ttjs S' 
ev Tip (hXeKpdvo) Kajjufjecus to fxev KLveiTai to eV auroj 
T(p oXcp Kivovfievcp, dvdyKrj 8' elvai tl Kal dKivrjTOv, 

30 o hrj (jyafxev hvvdpiei fxev ev elvai G7)pielov, evepyeia 
he ylveudai hvo' ojgt el to t^wov rjv ^paxiO)v, iv- 
Tavd^ dv 7TOV rjv rj dpx'rj ttjs i/jvxt]? y) KLVovora. 
67761 8' evSex^Tai Kal Trpo? rrjv x^^P^ ^X^^^ '^^ 


ev Tjj x^^P^y (jyavepov otl ovk dv etr) ev ovSeTepco 

35 7) ^vx^] Twv eoxdTOiv, ovT^ ev Tw iaxdTCp tov 

KivovfJLevov ovT^ ev ttj eTepa dpxfj- kolI ydp to 

702 b ^vXov ex^L Kal dpxr]v Kal TeXog npog ttjv x^^P^- 

oidTe Sta ye tovto, el fii] ev ttj ^aKTiqpia rj Kivovoa 

diTO TTJs ^^XV^ ^PXV iv^fynv, ouS' ev ttj X^^P^' 

opLolojg ydp ex^^ Kal to aKpov ttjs x^^P^^ rrpos tov 

Kaprrov, Kal tovto to jJiepog Trpog to (LXeKpavov. 

5 ovSev ydp hiacj^epei ra TrpodTrecfiVKOTa tcov fxiq 

" i.e. the same relation as the forearm has to the elbow, 

* i.e. the end of the stick where it meets the hand. 

* i.e. the origin of the movement of the hand which is 
situated in the wrist. 

** It is impossible to find a word in English which covers 
the double meaning given to apxn here and in the previous line 
(see note on 698 b 1). The sentence /cat 70,^x6^1^X01' . . . x"/"^ 
explains why the apxh Kivrjaecos of the hand is called rj Mpa 
oiPXVi viz. that there is another dpxv (in the sense of " be- 
ginning") in the stick, namely, the point nearest the hand. 


Now that which first causes movement in the 
animal must be situated in a definite beginning. 
Now it has already been stated that the joint is the 
beginning of one thing and the end of another ; where- 
fore nature employs it sometimes as one and some- 
times as two. For when movement is being origin- 
ated from it, one of its extreme points must be at 
rest, while the other must move ; for we have already 
said that what causes movement must be supported 
on something which is at rest. The extremity, there- 
fore, of the forearm is moved and does not cause 
movement, but in the elbow-joint one part, namely 
that which is situated in the actual whole which is in 
motion, is moved, but there must also be something 
which is unmoved ; and this is what we mean when 
we say that a point is potentially one but becomes 
actually two. So if the forearm were a living creature, 
it is somewhere near this point that the origin of move- 
ment set in motion by the soul would be situated. 
Since, however, it is possible for an inanimate object 
to bear this same relation to the hand,° for instance 
if one moves a stick in one's hand, it is clear that the 
soul could not be situated in either of the extremities, 
neither in the extremity of that which is moved ^ nor 
in the other origin of movement (apX'D ^ '» ^^^ ^^^ stick 
has an end and a beginning (opxv) ^ hi relation to the 
hand. So, for this reason, if the origin of movement 
set up by the soul is not situated in the stick, it is not 
situated in the hand either ; for the extremity of the 
hand * bears the same relation to the wrist as the 
latter does to the elbow. For there is no difference 
between what is attached by growth and what is not 

• i.e. the point where the hand joins the stick. 



yiverai yap ojoirep d(f)aip€T6v [xepos rj PaKrrjpla. 
avdyKT) dpa ev /xT^Se/xta etvat dpxfj, t] icrnv aAAou 
reXevrij, /xr^Se et rt iarlv erepov eKelvov i^wrepo), 
OLOV rod fiev rrjg ^aKrrjpLag iaxd-rov eV rfj X^'-P'^ 
7) oLpxTj, TovTov S' €v KapTTCp . €L Se /XT]S' iv rfj 

10 x^i-Ph on dvcoTepco 'in, rj dpx^ oi;S' ivravda' ert 
yap rod ojXeKpdvov fievovros KLveiraL drrav ro 
Kdroj Gwex^S' 

IX. 'Ettci S* oixoiojs ex^i aTTO tu)V dpiarepajv 
Kal 0,770 rdJv Se^Lcov, Kal a/xa rdvavria /ctvetrat, 
cl)ot€ fjLT) elvai ro) rjpepLelv to Se^iov KLveZudai to 
dpiOTepov fiTjh^ ai) tw tovto eKelvo, del 8' iv to) 

J 5 dvojTipw dii(j)OTipa>v tj dpx'ij, dv'dyKrj iv to) fiiao) 
etvai TTjv dpx^i^ Trjs ijjvxrjS ttj? KLVovar)S' dix(f)OTipujv 
yap Tihv aKpcov to fxicrov 'ioxo^Tov. opLoioJS 8' €;)^ei 
TTpos Tas KLVTjCjeLs TOVTO Kal rd? aTTO Tov dvco Kal 
KdTO), OLOV Tas drro ttjs K€(^aXrjg KaV' Tag dno rrj? 

20 pdx^(JL>£ ToZs ixovGL pdxt-v. Kal evX6ya>s Se tovto 
avfx^i^r^Kev Kal yap to aladr^TLKov ivTavda etval 
(JiapLCV, cocrr' dXXoiovjjiivov Std ttjv auerd-qcnv tov 

TOTTOV tov TTepl TTjV dpX'TjV Kal jXeTa^dXXoVTOS TOL 

ixdfJLeva GVfJLfieTa^dXXei iKTeivopievd re Kal avvayo- 

fxeva rd /jLopia, cocrr' i^ dvdyK-qs 8td raura yiveaOai 

25 TT^v KLvqoLv Tols l,cx)ois. TO he fiiaov TOV crco/xaros" 

* Kal scrips! : irpos libri. 

*• This is simply a restatement of the doctrine of 702 b 1-4. 
The true dpxv is not situated in the extremitj^ of the stick 
nearest to the hand (which is an dpxv as being the place 
where the stick begins in relation to the hand), nor yet in any 
other member, such as the wrist, which is still farther away 
from the stick and is an apxv as being the origin of motion 
in the hand. The wrist, elbow, and shoulder are all of them 


so attached ; for the stick becomes a kind of detached 
member. The origin of movement, therefore, cannot 
be situated in any origin which is the termination of 
something else, nor in any other part which is farther 
from it ; for example, the origin of movement of the 
extremity of the stick is in the hand, but the origin 
of the movement of the hand is in the wrist." And 
so if the origin of movement is not in the hand, be- 
cause it is still higher up,* neither is it in this higher 
position ; for, again, if the elbow is at rest, the con- 
tinuous part below it can be set in motion as a whole. 
IX. Now since there is similarity in the left and the 
right sides of the body, and the opposite parts can be 
moved simultaneously, so that it is impossible for the 
right side to move just because the left is at rest or vice 
versa, and the origin of movement must be in that 
which lies above both sides, it necessarily follows that 
the origin of movement in the moving soul must be 
between them ; for the middle is the Hmit of both 
extremes. And it stands in the same relation to the 
movements above as to those below, to those, for 
example, which proceed from the head and to those 
which proceed from the spine in animals which have 
a spine. And there is good reason for this ; for we 
say that the organ of sensation is also situated in 
the centre of the body ; and so if the region round 
about the origin of movement is altered by sense- 
perception and undergoes change, the parts which 
are attached to it change with it by extension or con- 
traction, so that in this way movement necessarily 
takes place in animals. And the central part of the 

dpxai in relation to the parts below them, but the true apx-n 
is situated in the soul, which lies in the centre of the body. 
* i.e. the wrist. 



702 b ^ 

[lepos Svi'dfiei [xev eV, evepyeia 8* dvayKj] ytveadaL 
TrXeico' Kol yap dfxa KLvelrai rd KcbXa diro rrjs 
dp)(rjs, Kol darepov TjpepiOVVTOS Odrepov KiveiTai. 
Xiycxj 8' olov eTTL rrjs ABF to B Kivelrai, Kivel 
Se TO A. aAAa piriv Set ye tl 'qpe/JLelv, el /xeAAet 

80 TO ixev KLveiGOai rd 8e KiveZv. ev dpa Swdfia oV 
TO A evepyeia Suo eurai, toar dvdyKT] jjltj OTiyiJLrjv 
dXXd pLeyeOos tl etvai. dXXd pLrjv ivSex^Tat to T 
dpLa TO) B KLveloOai, oj<jt dvdyKrj dpL(f)0T€pas Tds 
dpxds Tds iv TO) A KLvovfjLeuas Kivelv. 8et tl dpa 
€LvaL TTapd raura? eTepov to klvovv Kal pbrj klvov- 

85 pL€POV. aTTepelSoLVTo pL€v ydp dv TO, a/cpa Kal at 

dpXOil OLL iv TO) A TTpOS aAArJAtt? KLVOVpiivCOV, a)G7T€p 

703 a dv et TLveg ra vwTa dvTepelhovTes klvoI^v Td OKeXrj. 

dXXd TO KLVOVV dpL(f)Oj dvayKalov elvaL. tovto 8' 
ioTLV Tj i/jvx'q, eTepov fxev ovaa tov pieyedovs tov 
TOLovTov, ev TovTcp 8' ovoa. 

X. Kara piev ovv tov Xoyov tov XeyovTa ttjv 

6 aLTLav TTJs KLvqoeojs eoTLV Tj dpe^LS TO pLecrov, o 

KLvel KLvovpievov ev he tols ipupvxoLs aco/xaat Set 


pLev pLTj rrecfyvKos Se KLveZv SuVarat 77aa;^ety /car' 

dXXoTpiav hvvapLLV to Se klvovv dvayKalov e;3^ety 

TLvd SvvapLLV Kal LGXvv. irdvTa 8e ^atVerat ra 

10 t,a)a Kal exovTa irvevpLa GvpL(f)VTOV Kal LOXvovTa 

TOVTOJ, {tLS pev ovv Tj OCJOTTlpia TOV GVp(f)VTOV 

TTvevpLaTOS, eLpr]TaL iv aAAotS".) tovto Se Trpog 
TTjv dpx^v Trjv i/jvx^'KTjv eoLKev opLOLOJS ^X^^^ cooTrep 

""See Introd. p. 436. 


body is potentially one, but actually must necessarily 
become more than one ; for the limbs are set in 
motion simultaneously from the origin of movement, 
and when one is at rest the other is in motion. For 
example, in ABC, B is moved and A moves it ; there 
must, however, be something at rest . 

if one thing is to be moved and 
another is to move it. So A, though 
potentially one, will be actually two, 
so that it must be not a point but a 
magnitude. Again, C may be moved 
simultaneously with B, so that both 
the origins in A must cause movement by being 
moved ; there must, therefore, be something other 
than these origins which causes movement without 
being itself moved. Otherwise, when movement took 
place, the extremities, or origins, in A would rest 
upon one another, like men standing back to back and 
mo\dng their limbs. There must be something which 
moves them both, namely the soul, other than such 
a magnitude as we have described but situated in it. 
X. In accordance with the definition which defines 
the cause of motion, desire is the central origin, which 
moves by being itself moved ; but in animate bodies 
there must be some bodily substance which has these 
characteristics. That, then, which is moved but does 
not possess the natural quality of setting up move- 
ment may be affected by a power external to it, and 
that which causes movement must possess some 
power and strength. Now all animals clearly both 
possess an innate spirit and exercise their strength 
in virtue of it. (WTiat it is that conserves the innate 
spirit has been explained elsewhere. <*) This spirit 
seems to bear the same relation to the origin in the 



TO ev rats /ca/xTrat? (jr]iJL€LOv, to kwovv Kai kwov 

fJLGVOVy TrpOS TO OLKLVrjTOV. €7761 8' T] apX^ ''^Ot? 

/xei' ep' rfj KapSia TOt? 8' ei^ tco dvdXoyov, 8td rovro 
Kal TO TTvevfia to <JVjj.ff)VTOv ivTavOa (j)aiveTai 6v. 

15 TTOTepov jxev ovv TavTOv Igtl to TTvevfia del -r) 
yiveTai del eTepov, eoTCo d'AAos" Adyo? (d avTOS 
yap idTL Kal rrepl tcov dXXcov iiopicov)' (jyaiveTai 8' 
ev^vojs ^X^^ TTpog to kivtjtikov elvai Kal rrapey^eiv 
Igxvv. Ta 8* epya ttjs KivrjGeios (Lais Kal eX^cg, 

20 ojCTTe Set TO opyavov av^dvecrOai t€ 8waa^at Kal 
avGTeXXeoOai. TOiavTi] 8' eo-Ttv rj tov irvevpiaTos 
(j)VGLS' Kal yap d^iauTos avoTeXXofjievr], Kal 
^LaaTLKT] Kal waTLKT] 8td TT^v ai)Tr]v atTtar, /cat 
ex^^ Kal ^dpos TTpog Ta TTvpwSr] Kal Kov^oTiqTa 
TTpos TOL evavTia. hel 8e to fieXXov Kivelv (jltj 

25 dAAotcoo-et TOiovTOV elvai' KpaTei yap KaTa ttjv 
vnepox'^v TO, (fiVcriKa GcofxaTa dAATJAojv, to ^xev 
Kovcj)ov KaTOj VTTO TOV ^apVTepov diToviKcoixevoVy 
to he ^apv dva> vtto tov Kov^OTepov. 

"^0.1 jjiev ovv Kivel KLVovy^evco {JLOpio) rj j/fup^rJ^etpi^Tat, 
Kal 8t* "rjv aiTiav VTToXrjTTTeov 8e GweoTavaL to 

80 t,ipov ojGTtep ttoXlv evvoiiovfjievrjv. ev t€ yap ttj TToXei 
OTav dVaf gvgttj^ -q Ta^is, ovSev Bel Kex^p^crp-^^ov 
fjiovdpxov, ov Set Trapelvai Trap* eKaGTOV twv 
yivofjievojv, dAA' auTO? eKaGTOS TTOiel to, avTov 
(vs TeTaKTai, Kal yiveTai ToBe pueTCL ToSe 8td 
1 (rvarfi P : arfj ESY. 

" For this meaning of d^iiaaTos cf. Plato, Tim. 61 a. The 
action of the wev/jLa is represented as resembling that of the 
breath in the lungs ; when the breath contracts it lacks force 
and the lungs collapse, when it expands it thrusts outwards 
and exercises force. 

'' Namely, expansion. 


soul as the point in the joints, which moves and is 
moved, bears to that which is unmoved. Now since 
the origin is in some animals situated in the heart, in 
others in what corresponds to the heart, it is therefore 
clear that the innate spirit also is situated there. 
Whether the spirit is always the same or is always 
changing must be discussed elsewhere (for the same 
question arises about the other parts of the body) ; 
at any rate it is clearly well adapted by nature to be 
a motive power and to exercise strength. Now the 
functions of movement are thrusting and pulling, so 
that the organ of movement must be able to increase 
and contract. And the nature of spirit has these 
quahties ; for when it contracts it is without force," 
and one and the same cause ^ gives it force and en- 
ables it to thrust, and it possesses weight as compared 
with the fiery element, and lightness as compared 
with the contrary elements,'' Now that which is to 
create movement without causing alteration must be 
of this kind ; for the natural bodies ^ overcome one 
another according as one of them prevails, the light 
being conquered and borne down by the heavier and 
the heavy borne up by the lighter. 

We have now stated what is the part by the move- 
ment of w^hich the soul creates movement and for 
what reason. The constitution of an animal must be 
regarded as resembling that of a well-governed city- 
state. For when order is once established in a city 
there is no need of a special ruler with arbitrary 
powers to be present at every activity, but each indi- 
vidual performs his own task as he is ordered, and one 
act succeeds another because of custom. And in the 

" The contrary of fire is water, c/. Be gen. et corrupt. 331 a 1. 
^ i.e. the elements. 

Q 475 


TO evos' €v re rots' icoois to avTO tovto Ota ttjv 
35 <f)V(nv yiv€Tai /cat to) 7re^u/<eVat eKaoTOV ovtco 
avGTOLVTOJv rroielv to avTov epyov, oj(jt€ firjSev 
8etv iv eKOLGTW etpat ijjvx'^v, aAA' eV rtvt dpxfj '''ov 
703 b CTctj/xaros" ovgtjs rdAAa l^rjv fiev toj 7Tpocr7T€(f)VKevaL, 
TToieiv he TO epyov to avTcov 8td ttjv (J)volv. 

XI. Hios /xev ovv KLveiTai tcls eKovdias /ctvTJoet? 
TO, t,ipa, /cat 8td rtVa? atrtas", etpT^rat* /ct^etrat 8e 
5 Ttvas" /cat OLKOVGLOvs eVta rcDi^ [Jiepojv, tols 8e 
TrAetora? ou;^ eKovalovg. Xeyco 8* (xkovglov? fiev 
OLOV TT]v TTJs KapStas T€ /Cat TT^v Tou alSoLOV {noXXaKLs 
yap (f)av€VTOs rtvos", ou /xeVrot /ceAeucrai^ros' tol> 


iyp-qyopaiv /cat dyaTTVOTjy, /cat oorat d'AAat rotaurai 
10 elcTLV. ovOevos yap tovtcov Kvpia airXix)? icrTLV 
ov6* 7) (f)avTaala ovO^ rj ope^is, dAA* evethr] dvdyKr] 
dXXoLovodai TOL l,ci)a (jiVGLKrjv olXXolcoglv, dAAotou- 
/xeVcov 8e TcDv fioptcov to. fiev auf eo^at rd 8e c/idiveLV, 
coctt' '^'817 KiveloOai /cat fxeTa^aXXetv rds" Tre^u/cutas" 
ex^oOaL fieTa^oXas dAAT^Aoji^ (atrtat 8e rcDv 
1^ KLvqaeojv OepfjLOTrjTes re /cat ipv^eis, at t€ dvpadev 
/cat at ei^rds" VTrdpxovaai (fyvcnKai), /cat at irapd 
Tov Adyov 817 yivofxevai KLvrjoeis tcjv prjdevTCOv 
fjiopLOJv dAAottuoeco? GvpLTreoovorjs yivovTai. r] yap 
voriGLS /cat 17 </)avTaota, oyartep elpryrai npoTepoVy to 
TTOnqTiKa ToyvnadrifxdTCJV 7TpoG(f)epovGLV rd ydp et87] 

20 TCUV TTOLTJTLKcbv 7TpOU(j)epOVGLV . jJidXlGTa 8e TcDv 

fjLopLOJV TavTa TToiet eTTih-qXcDS 8td rd cooTrep ^(Sop' 
Kex^JoptGfjLevov eKdTepov elvai rcDv pLopiajv [• tovtov 

" See note on 698 b 1. 
* Viz. the heart and the privy member. 
" 701 b 18 ff. 


animals the same process goes on because of nature, 
and because each part of them, since they are so 
constituted, is naturally suited to perform its own 
function ; so that there is no need of soul in each 
part, but since it is situated in a central origin of 
authority over the body," the other parts live by 
their structural attachment to it and perform their 
own functions in the course of nature. 

XL We have now discussed the manner of the 
voluntary movements of animals, and the cause of 
them. Some of their parts, however, undergo certain 
involuntary movements, though most of these are 
really non-voluntary. By involuntary I mean such 
movements as those of the heart and of the privy 
member, which are often moved by the presentation 
of some image and not at the bidding of reason. By 
non- voluntary I mean sleeping and waking and respira- 
tion and the like. For neither imagination nor desire 
is strictly speaking responsible for any of these move- 
ments ; but, since animals must necessarily undergo 
physical alteration, and, when their parts undergo 
alteration, some increase and others decrease, and so 
their bodies immediately move and undergo the 
natural sequence of changes (the causes of their 
movements being the natural heatings and chillings, 
both external and internal), the movements too of 
the above-mentioned parts ^ which occur contrary to 
reason are due to the occurrence of a change. For 
thought and imagination, as has already been said,* 
induce the states which cause the affections ; for 
they present the images of the things which cause 
them. Now these parts act in this way much more 
conspicuously than any others, because each is as it 
were a separate vital organism[, the reason being that 



703 b 

8' aiTLOV OTL exovGLV vyporrjTa t^curiK-qv]} rj fxkv ovv 

Kaphia (f>av€p6v St' rjv alriav ras y^p^ apxa^ e;^et 
rojv alodiquecov to 8e piopiov to yevvqTiKov otl 

25tolovt6v ioTiy GTjiielov Kal yap i^ep^eTai i^ 
avTOV axjTTep t^toov tl tj tov GirepixaTO? Sura/xt?. 
at Se KLvqaecg ttj re apXT? ^'^^ '^^^ fJLoplcov Kal 
rots' fiopioig OLTTO rr^s" o.pxrJ9 evXoyojs ovpi^aivovGi, 
Kal TTpos dAArjAa? ovtcxjs acjuKvovvTai. Set yap 
vorjaaL to A dpx^^. at ouu KLvrjaeLS Kad* e/caaroy 

30 GTOLX^iov Tcov imyeypajjifievcov irrl ttjv dpx^^ d(j)iK- 
vovvTai, Kal (xtto ttjs dpxrj? Kivovfievrjs Kal //era- 
^aXXovG-qg, eTreiSr] 77oAAa hvvdfx€i ecrrtV, -q fiev tov 
B dpx'^ ^'^l '^o B, Tj Se TOV r errl to T, rj S' dfX(f)OLV 
€77* dfjicjia). diTo he tov B eVt to V to)^ dno [xev tov 

35 B iirl TO A iXdelv wg err* dpx^jvy diro he tov A eVt 

TO r CO? avr' dpxyj?- otl Be OTe fxkv raura* vorjodv- 

Tojv ytVerat o^ KLvrjGig r) Trapd tov Xoyov ev rot? 

lO^A pLopioLs, 6t€ S' ol>, atrtop' to ore /xev vrrapx^LV ttjv 

TTaO-qTLKrjv vXtjv 6t6 8e /xi) ToaavTr^v rj ToiavTiqv. 

Ylepl pLev ovv tcov pLoplcov eKdoTov tcov [,cpcov, 

704 b Kal irepl ipvxTJS, €tl Se nepl alGdrjG€oos Kal vttvov 

Kai pLV-qpi-qs Kal Trjg kolvtjs KLvrjuecos, elpiqKapiev 
ret? atrta?* Aot77oy Se irepl yeveoecos elireZv. 

* TovTov , , . i^cjTLKrjv ut interpolamentum del. Jaeger. 

2 yap cm. EY. 

3 Tw EP : ry 0^ Y : t6 5^ S. 

* ravTo. Jaeger : to, avTO. P : raOra ESY. 

• These words are probably an interpolated gloss ; they 



each contains vital moisture]. ° The reason for this as 
regards the heart is plain, for it contains the origins 
of the senses. That the generative organ is of the 
same nature is shown by the fact that the seminal 
force comes forth from it, being as it were a living 
thing. Now it is only in accordance with reason that 
movements are set up both in the central origin by 
the parts and in the parts by the central origin, 
and thus reach one another. Let A be the central 
origin ; the movements at each letter in the diagram 
drawn above ^ reach the central origin, and from the 
central origin, w^hen it is moved or undergoes change 
(for it is potentially many), the origin of movement 
in B goes to B, and the origin of movement is C to C, 
and of both to both ; but from B to C it travels by 
going from B to A as to a central origin, and from 
A to C as from a central origin. Movement, however, 
contrary to reason, sometimes takes place and some- 
times does not take place in the organs as the result 
of the same thoughts, the reason being that the 
matter which is liable to be affected is sometimes 
present and sometimes not present in the proper 
quantity and quality. 

We have now dealt Nvith the reasons for the parts 
of each animal, the soul, and also sense-perception, 
sleep, memory, and general movement. It remains 
to deal with the generation of animals. 

are unnecessary in view of the following sentences and con- 
tradictory in doctrine to them. 
'' See figure on p. 473. 




Chap. I. Introduction. Problems which arise about 
animal locomotion. Different number of limbs and 
different modes of bending them found in different animals. 

II. Assumption of generally-accepted principles and 

III. Animal movement requires (1) a resisting surface 
against which the limbs can press, (2) a distinction of 
active and passive parts in the animal. 

IV. ITie dimensions of living bodies. Superior and 
inferior determined by function and not by position. 
Plants and animals compared. Distinction of front and 
back, right and left. The right, as the source of move- 
ment, superior to the left. Man the most highly differen- 
tiated of the animals. 

V. Bipeds, quadrupeds, polypods and footless ammals 
distinguished. Quadrupeds inferior to bipeds. Man the 
highest form of biped, being the most " natural." 

VI. All movement in the animal must originate in a 
common centre, equidistant from the centres of movement 
in the limbs. 

VII. Red-blooded animals move at four points : such 
animals are a continuous whole, while bloodless animals 
and polypods are composed of a number of separate 
entities. Even limbless red-blooded animals move at 
four points. 

VIII. Reason for the absence of limbs in snakes. Limbs 
necessarily even in number. 

IX. Flexion necessary to movement, even in limbless 
animals. Its mechanism explained. Illustrations from 
leaping, flying, and swinuning animals. 

X. Movement of birds. Use of the tail to guide flight, 


XI. Man, the only erect animal, compared with the 
birds. Winged human beings an impossible invention of 
the artists. 

XII. Differences of flexion in the limbs of man and of 
the quadrupeds explained. 

XIII. The different modes of flexion enumerated and 
illustrated by diagrams. 

XIV. " Diagonal " movement of the legs of quadrupeds. 
Movement of crabs. 

XV. Birds and quadrupeds compared. The structure 
of the legs of birds. Oblique attachment of wings and 
fins. The structure of oviparous quadrupeds. 

XVI. Movement of bloodless animals. The peculiar 
movement of the crab. 

XVII. Crabs, lobsters, flat-fish, and web-footed birds. 

XVIII. ^^lly birds have feet, while fishes have not. 
Fins and wings compared. 

XIX. The movement of testaceans. Conclusion, 


Z = Codex Oxoniensis Collegii Corporis Christi W.A. 


U = Codex Vaticanus 260. 

S = Codex Laurentianus 81. 1. 

P = Codex Vaticanus 1339. 

Y = Codex Vaticanus 261. 
Leon. = Latin translation of Nicholas Leonicus. 
Mich. = Greek commentary of Michael Ephesiug. 

q2 483 


704 a 

I. Ilepl Se T<JL)V XPV'^^H'^^ fiopLCov rots ^ojols 

5 TTpos TTjV KLvrjULv TTjv Kara TOTTOV €TnaK€TTriov Sta 

TtV alriav tolovtov iariv eKaarov avrtjjv /cat rivos 

€V€K€V VTTOLpX^l' aVTOlS , €TL Se 7T€pl TCJbv Siat^OpOJV 

TOiV re TTpos dXXr]Xa roXs rod avrov /cat ivos (^a)ov 
ixopiois, Koi TTpos TO. T(x)v aXkojv rcjv Tip yivei 8ta- 

(f)6p(X)V. TTpcJOTOV Se Xd^a>fJL€V TTepl OGCOV eTTt- 


10 "Ecrrt Se TTpchrov /xev ttogols iXax^crroLs rd foJa 
KLveZrai ariii€iois, eVetra Sta rt rd fiev eVat/xa 
rerrapcn rd 8* dvatfxa TxAetoCTt, /cat /ca^oAou 8e Sta 
TtV alriav rd fiev dnoSa rd 8e StVoSa rd 8e 
rerpaTToSa rd 8e 77oAu7ro8a rcov ^cocov icrrl, /cat 
8ta Tt TTavr dprlovs e%€t rous' TroSas", ooarrep e;^et 

15 TToSa? auToiv oAo;? 8' ot? KLveZrai oiqixeiois, dpria 
ravr iariv, 

"Ert hk 8ta rtV* alriav dvdpojTTOs [xev /cat opi'ts- 
SIttovs, ol 8' IxOves aTToSes eluiv /cat ra? Kapufjeis 
o re dvdpcDTTOs /cat o opvis SiTToSes ovres ivavrias 
exovGL rwv gkcXcov. 6 ptev ydp dv9p<x)TTos CTit 

20 rrjv TT€pL(f)€p€Lav KafiTTreL ro a/ceAo?, o 8' opi^ts" 
eVt TO kolXov. /cat o dvdpojTTOS avros avrca 



I. We must next discuss the parts which are useful 
to animals for their movement from place to place, 
and consider why each part is of the nature which 
it is, and why they possess them, and further the 
differences in the various parts of one and the same 
animal and in those of animals of different species 
compared with one another. We must first decide 
what questions we have to discuss. 

One question is, what is the smallest number of 
points at which animals move ; the next is, why red- 
blooded animals move at four points, while bloodless 
animals move at more than four ; and, in general, 
why some animals are without feet, others biped, 
others quadrupeds, and others polypods, and why all 
that have feet at all have an even number of feet ; 
and, in general, why the points at which movement 
is made are even in number. 

We must further consider why a man and a bird are 
bipeds, while fishes are without feet ; and why a man 
and a bird, being both bipeds, have opposite bend- 
ings of the legs. For a man bends his legs in a convex 
direction, a bird in a concave direction ; and a man 



ivavrlcos ra OKeXiq /cat tovs ^paxiovag- rovs /xev 
yap iirl to koIXov, ra 8e yovara cttl rriv irepi- 
(jiepeiav Kdjirrrei. /cat ra rerpoLTToSa ra Jojoro/ca 
rots' t' av6pcx)rrois evavriojs KapnTrci /cat aura 
auTots"* ra fX€v yap rrpoaO la GKeXrj em ro Kvprov 
704 b rrj<s 7T€pi(f)€p€Las /ca/XTrret, ra S' orriuOia irrl ro 
6 KoZXov. en Se ra)v rerpaTTohojv ocra fjurj l,cporoKel 
aXX ojoroKeZ, tStoj? /cat els ro TrXdytov /ca/XTrret. 
Trpo? 8e rovroLs 8ta rtV alriav rd rerpdrroha 
Kivelrai Kara Sidpierpov. Trepl Srj irdi^rajv rovrojv, 
/cat oo-a d'AAa Gvyyevrj rovrois, ra? air las Oecop-q- 
reov. on fxev yap ovrco ravra GvpL^alvei, SrjXov ei< 

10 rrjs Lcrroplas rrjs (f)VGLKrjSy Stort Se, vui' GKenreov. 

II. 'Ap)(r) Se rrjs GKeijjeojs vnoOepLevoLS ols 

elojQapLev XPV^^^^ TroAAa/cts" irpos rrjv jxedohov 

rrjv (f)vaLKTJv, Xa^ovres rd rovrov exovra rov 

rpoTTOV ev ttolgl roZs rrjs cfyvaews epyois. rovrcov 

15 8' ev jLteV eanv on rj (f)VGLs ovOev TTOiet fidrrjv, 
aAA' del e/c rcov ev'^exopievcov rfj ovala rrepl eKaarov 
yevos t,(pov ro dpiurov hioirep el ^eXnov coSl, 
ovrcos /cat ex^c Kara (f)vcnv. en rds SiaardaeLs 
rod fjueyeOovs, TToaai /cat iTolai ttolols VTrdpxovau, 
Set Xa^elv. elal yap StaGrdaeis liev ef , Gvl,vyiai 

20 he rpels, [xia fiev ro dvoj /cat ro Kdrco, Sevrepa Se 
rd efjLTTpoGOev /cat ro oTTLGOev, rplrrj Se ro Se^Lov 
/cat ro dpiGrepov . rrpds Se rovrois on rwv KLvrjGewv 
rcJov Kara ronov dpxoil cLgls /cat eX^ts. Kad 
avrds fiev ow avrai, Kara GviJi^e^rjKos Se Kivel- 

* i.e. the front rijsrht foot with the left back foot, and the left 
front with the right back. ^ The Iflstoria Aniynalium. 

" Leon, renders eodeni . . . modo which seems to im- 
ply that he was translating rbf avrbv IxoJ'T'a Tpbirov. 


himself bends his legs and his arms in opposite 
directions, the arms concavely and the knees con- 
vexly. And viviparous quadrupeds bend their limbs 
in the opposite way to a man's and in opposite 
ways to one another ; for they bend their front legs 
convexly and their back legs concavely. Further, 
quadrupeds which are not viviparous but oviparous 
have the peculiarity of bending their legs sideways. 
A further question is why do quadrupeds move their 
legs diagonally. ** 

We must examine the reasons of all these and 
similar facts ; that they are facts is clear from our 
Natural History,^ and we have now to examine their 

II. We must begin our inquu-y by assuming the 
principles which we are frequently accustomed to 
employ in natural investigation, namely, by accept- 
ing as true what occurs in accordance with these 
principles *^ in all the works of nature. One of these 
principles is that nature never creates anything 
without a purpose, but always what is best in view 
of the possibilities allowed by the essence of each 
kind of animal ; therefore, if it is better to do a thing 
in a particular manner, it is also in accordance with 
nature. Further, we must accept the dimensions of 
magnitude in the size and quahty in which they are 
present in various objects. For there are six dimen- 
sions grouped in three pairs, the first being the 
superior and the inferior, the second the front and 
the back, and the third the right and the left. We 
must further postulate that the origins of movement 
from place to place are thrusting and pulling. These 
are movements per se ; that which is carried by 



rat TO cpepofxevov vtt aAAov ov yap avro ooKei 
705 a KLvelv avro dAA* utt* aXXov KLveloOai ro vtto rivog 


III. TovTCOv 8e hicjpi(jp,ivcov Xeyajfiev ra rovrcov 
i(j)e^rj?. Tcov Sr] l,a)Ojv ocra /xera^aAAet Kara 
roTTOv, ra fxev adpoco Travrl rep crcu/xart /xera^aAAet, 
6 KaOdirep ra aX\6p.€va, ra 8e /caret p,epos^ Kaddrrep 
ru)v TTopevofxevojv €Kaorov. iv dfjL,(f)or€paLS 8e rals 
Ixera^oXals ravrats del fxera^aXXei ro KLVovpLevov 
d7Toarripit,6pi€vov npos ro VTroKeifievov avrw. 
BiOTTep idv re V7TO(f)epr)raL rovro ddrrov rj cocrr 

10 €^€LV dTTepeLdaadaL ro TTOLOvfievov ctt' avrov rrjv 
KLvr](jLU, edv 6* oXa)S ixrjSepLiav exjj rots KivovfidvoLs 
dvrepeioiv , ovdev ctt' avrov hvvarai Kiveiv eavro. 
/cat yap ro aXXofievov /cat Trpo? avro^ dnepecSopLe- 
vov ro dvoj /cat Trpos" to vtto rovs vroSas" TTOieZrai 
rrjv dXoLV e)(€L ydp riva dvrepeLcriv vpos dX\r]\a 

15 TO, jLtopta iv rals KapLTrals, /cat oAoj? ro iTiet^ov 
TTpos ro TTue^o/JLevov. 8to /cat ot TrivradXoi dXXovrai 
TrXeXov €.)(ovres rovs dXrrjpas t) fJirj exovres, /cat 
ot diovres Odrrov diovoi rrapaaeLovreg rds ;\;etpa9* 
y Lver ai ydp ris dTripeiois ev rfj Staracret Trpos ras 
Xelpas /cat rovs Kapnovs. del Se ro KLvovfievov 

'-'0 hvalv iXaxicrroLS XP^P'^^^^ opyavLKoZs jxepecrL 
TTOielrai rrjv fiera^oXijv, rep p,ev (hoirepavel OXi^ovrLy 
ra> he dXi^ofxevu). ro puev ydp fjuevov dXi^erai hid 

^ Kara ixipo$ Z : n.ipei S : rot j fioplois cet. 
a avTb PUY: avrb S: iavrb Z. 

" Special weights {aXrTjpes) or sometimes stones were held 
in the hands and thrown backwards by jumpers while in the 
air to add to their impetus ; cf. Norman Gardiner, Greek 



something else is only moved accidentally, for what 
is carried by something else is regarded not as mov- 
ing itself but as being moved by something else. 

III. These points having been decided, let us 
proceed to the considerations which follow from 
them. Of the animals, then, which change their local 
position, some do so with their whole body at the 
same time, for instance those which jump ; others 
move part by part, for example those that walk. 
In both these changes the animal that moves makes 
its change of position by pressing against that which 
is beneath it ; and so, if the latter slips away too 
quickly to allow that which is setting itself in motion 
upon it to press against it, or if it offers no resistance 
at all to that which is moving, the animal cannot move 
itself at all upon it. For that which jumps performs 
that movement by pressing both on its own upper 
part and on that which is beneath its feet ; for the 
parts in a way lean upon one another at their joints, 
and, in general, that which presses leans on that 
which is pressed. Hence athletes jump farther if 
they have the weights in their hands than if they 
have not," and runners run faster if they swing their 
arms ^ ; for in the extension of the arms there is a 
kind of leaning upon the hands and wrists. Now that 
which moves always makes its change of place by the 
employment of at least two organic parts, one as it 
were compressing and the other being compressed. 
For the part which remains still is compressed by 

Athletic Sports and Festivals, pp. 298 if., who proves by- 
experiment the truth of the statement made in the present 

'' On the importance attached by the Greeks to arm- 
action in running, especially in short races, cf. N. Gardiner, 
op. cit. p. 282. 



705 a , , 

TO <f>€p€Lv, TO 8' alpofxevov reLverau rep (jyipovri 
TO <j)opTLOv. hioirep a/xepe? ovhkv ovtcjo KLvrjOrjvai 
SvvaTOV ov yap e;\;et rrjv tov TTeicropievov koI tov 

25 TTOLrjaovTog iv avrw^ SidXTjipLV. 

IV. 'ETret 8' eldlv at hiaordueis tov dpidpiov 
€^, at? 6pii,€a6ai TT€(f)VK€ TOL ^a>a/ to re aVco /cat 
KOLTOJ Kal TO ejjLTTpoadev /cat OTTLodev, ert 8€ 86^101^ 
/cat dpiGTepov, to pikv avco /cat /caro; fiopLov iravT 
ex^i TOL t^oyvTa. ov jjlovov yap iv tols 1,(x)ols €OtI 
TO dvoj /cat Kara), dAAa /cat eV rots' (f)VTOLs. 8t- 

80 elXrjTTTaL 8' epyco, /cat ou Oecrei piovov ttj Trpos re 

Ti7t' yTyv /cat TOV ovpavov. odev /xev yap 1^ tt]? Tpo(f)7Js 

SidSoGLs /cat 7^ av^TjGis iKaoTois, dvoj tovt cgtIv' 

705 b TTpos o 8* eaxoLTOV avTTj Trepalvei, tovto Kdrco. 

TO pi€V yap dpx'ij Tts", to 8e Tripas' dpx^ 8e ro avco. 

KaiTOi S6^€L€V dv TOL? (j)VTol? OLKeloV elvai TO Kdroj 

pidXXov ovx dpLOLOis yap ex^i Tjj decret to avco /cat 
Kdrco TOVTOLs Kal Tot? t,a)OLS. ^X^'' ^^ Trpos p.ev 
6 TO dXov ovx op-OLCos, Kara 8e to epyov opLolcos. 
at yap pt^at etat to avco toIs ^vtoZs' eKeWev yap 
Tj Tpo(f>r) 8ta8tSoTat Tots <j)Vopiivois, /cat Xapi^dveu 
ravTais avTriv, Kaddnep Ta t,a)a T0X9 GTopaavv. 

''Oo'a 8e p,r] pLovov l,fj dXXd /cat t^cod ecTt, TOt? 

TOtouTOts" VTrdpx^i' TO T€ epLTTpoodev Kal TO oTTLodev. 

10 aiddrjCTLV yap e;\;et TauTa TrdvTa, 6pil,eTai 8e /caTO. 

ravTTjv TO T€ epLTTpooOev Kal to oTnoOev icj)* o 

p,ev yap rj a'tudrjais 7Te<^VKe Kal dOev IgtIv eKdoTOiSt 

1 avT(^ Jaeger : avrt^ libri. ^ ^<^a Y : ^Cbvra ceteri, 

• Cf, above, 704 b 19 ff. ^ Cf. De caelo, 294 b 17. 

* More literally "personal." 
' Cf. De vit. long, et brev. 467 b 2 ; Phys. 199 a 28. 


having to carry the weight, and the part which is 
raised is extended by that wliich carries the weight. 
And so nothing that is without parts can move in 
this manner ; for it does not contain in itself the 
distinction between what is to be passive and what 
is to be active. 

IV. Now the dimensions by which animals are 
naturally bounded are six in number, namely, 
superior and inferior, front and back, and also right 
and left." Now all living things have a superior and 
an inferior part ; for the superior and the inferior is 
found not only in the animals but also in plants.^ 
The distinction is one of function and not merely of 
position in relation to the earth and heavens. For 
the part from which is derived the distribution of 
nutriment and the growth in any particular thing is 
the superior ; the part to which the growth extends 
and in which it finally ends is the inferior. The one 
is a kind of origin, the other a termination ; and it is 
the superior which is an origin. It might, however, 
seem that in plants the inferior is the more essential ® 
part ; for the superior and the inferior are not in the 
same position in them as in the animals. Though in 
relation to the universe they have not the same posi- 
tion, they are similarly situated as regards function. 
For in plants the roots are the superior part ^ ; for it 
is from them that the nutriment is distributed to the 
parts that grow, and it is from their roots that plants 
receive it, as do animals from their mouths. 

Things which not only live but are also animals have 
both a front and a back. For all animals have sense- 
perception, and it is on account of sense-perception 
that the front and the back are distinguished ; for 
the parts in which the sense-perception is implanted 



efjLTTpoGuev ravT eon, ra o avriKeifxeva tovtols 


"Ocra 8e rcJov ^djcor /jltj jjiovov alaS-qGecos KOivcovel, 
16 dAAa Svvarai rroieiGOai ttjv Kara tottov fiera- 
^oX-qv avra St* avTwv, iv tovtols St)^ hicopiGTai 
TTpos Tots" Ae;^^etcrt to t' dptGrepov /cat to Se^LoVy 
ofJLOLCOs rot? TTporepov elprjyilvois €pya) nvl /cat ov 
6eG€L SLCjupLGfievov eKOLTepov aijTajv' odev jxev yap 
€GTL rod Gcofxaros rj rrjs /caret tottov jJueTa^oXi^s OLPXV 
20 (j)VG€Ly TOVTO fxev Se^Lov iKaGTO), TO 8' avTiKeipievov 

/cat TOVTiO 7T€(f)VK6s OLKoXovdelv dpLGT€p6v. TOVTO 

Se hnqpOpajTai fxaXXov eTepois eTepcov. oGa fieu 
yap opyaviKols /xepeat ;)(paj/xep'a [Xeycx) 8* olov 
ttogIv rj TTTepv^iv rj tlvi aAAoj toiovtco) ttjv elpr]- 
[xevTjV fji€Ta^oXr]V Trotetrat, Trepl jxev tol TOiavTa 

25 ixdXXov hiiqpdpojTaL to Xe-)(div' ocra 8e pirj tolovtois 
jjLopLOLg, avTcp 8e to) GcoixaTL ScaX-qifjeis noLovfieva 
TTpoepx^Tai, KaOdrrep evia tojv dTroSojv, otov ot 
T€ 6(j)€ts Kal TO TOJV KajjLTTCov ylvos y /Cat rrpos tovtols 
d KaXovGi yrjg eVrepa, vrrapx^^ p-^^ f<al iv tovtols 
TO XexOeVy ov pL7]v Stao-ecra^i^rat y' opioicos. 

80 "Ort 8' e/c Ta)V Se^Lcov r) dpx^j ttjs klvt^gccvs eGTL, 
GTjpLelov /cat TO (j)€peLV Ta (jiopTLa rrdvTas eVt Tots" 
dpLGTepoLS' ovTCxJs ydp evSex^TaL KLveZodaL to (fyepov, 
XeXvpuevov tov klv/jgovtos- (8to /cat do'/ccoAta^ouo't 
paov iiTL TOt? dpiGTepols' KLvelv ydp 7T€.(j)VKe to 
706a Se^toVj KLveLGOaL he to dpLGTepov.) a)GT€ /cat to 


^ 8t] Jaeger : 5^ libri. 

" Viz. superior and inferior. 
* i.e. from place to place. 



and whence every kind of creature derives it are at 
the front, and the opposite parts to these are at the 

Those animals which not only partake of sense- 
perception but can also of themselves make the 
change from place to place, in addition to the dis- 
tinctions already mentioned," have a further distinc- 
tion of left and right, these being each, like the above, 
distinctions of function and not of position. For the 
part of the body where the origin of change from 
place to place naturally arises is the right in each 
kind of animal, while the part which is opposed to 
this and naturally follows its lead is the left. 

There is a greater differentiation between right 
and left in some animals than in others. All animals 
which make the above-mentioned change ^ by the use 
of instrumental parts — for example, feet or wings 
or the like — show a greater differentiation between 
right and left in such parts ; those, on the other hand, 
that progress not by means of such parts but by 
moving the body itself in sections — like some of the 
footless animals, such as snakes and the caterpillars, 
and also earthworms — possess, it is true, this differ- 
entiation, but it is not nearly so clearly defined. 

That the origin of movement is from the right side 
is shown by the fact that men always carry burdens 
on the left shoulder ; for then it is possible for that 
which bears the weight to be set in motion, that 
which is to initiate the movement being free. (For 
this reason, too, it is easier to hop on the left leg ; for 
it is natural to the right leg to initiate movement, 
and to the left to be set in motion.) The burden, 
therefore, must rest not on the part which is to 
initiate movement, but on that which is to be set in 



fievo) dec eTriKeiouaf ear o ern rco klvovvti /cat rr] 
dpxfj TTJs KLvy]G€iDS imTeOfj, i^roi oXojs ov Kivqaerai 
6 r) -x^aXeTTCoTepov. ary/xetov 8' on arro rcov Se^Lcbv 
Tj apx^] Trjs Kiv-qoecxis Kal at Trpo^oXar Trdvres 
yap rd dpLcrrepd Trpo^dXXovrai, Kal ecrr cures' Trpo- 
^e^XijKaai'' rd dpiarepd fiaXXov, dv fXTj dno rvx^S 
crvfji^f]. ov ydp rep Trpo^ep-qKon Kivovvrai, dXXd 
rep dTTo^e^rjKOTL- /cat dpLvvovrat rols Seftotj. 

10 Sta ravTTjv 8e rrjv alriav Kal rd Se^ta raura ecrrt 
TTdvTCOv. 66 €v pikv ydp r) apx^) rrj? Ktvijcrecos, rd 
avTO rrdoi Kal iv rep avroj ttjv QeoLV ex^t, /cara cf)vo-LV 
Se^LOV S' eorlv dOev r) dpx'r] ttjs KLV^oecos ianv, 
Kal Sid TOVTO rd OTpopL^coSTj Tix)V oGrpaKoSepficov 
Se^id iravT* iariv. ov ydp inl rrjv iXiKiqv /ctvetrat, 

15 dXX iirl TO KaravTLKpv ndvra Trpoepx^Tat, otov 


diTO rajv Se^Lcov, KaKeivojv inl ravrd KLvovpievojv 
iavTols, dvdyKrj iravra Sefta eti^at opLolcos. dno- 
AeAu/xeVa S' exovcrt rd dpiarepd rcov t^cpcov p.d- 
Atcrra dvdpcxjTTOi Sta rd /cara (pvacv ex^^v /xaAtcrra 

20 ra)v t,a)OJV' (f)vaeL Se ^eXriov re rd he^idv rod 
dpiorepov Kal Kex(^p^crp.evov. 8to /cat rd Se^td 
iv rois dvdpcoTTOi? /xaAtcrra 8e^ia icrnv. Stcupta/xe- 
vojv Se rcov Se^ttDv evXoycos rd dpiarepd aKivrj- 
rorepd eari, Kal aTToXeXvjjieva pidXiara iv rovrois. 
Kal at aAAat 8' dpxol pidXiara /cara (f)vaiv St- 

25 copia^ievai iv ro) dvdpajTTCp VTrdpxovai, ro t' dvo) 
Kal rd ejjLTTpoadev. 

^ TTpo^e^X-qKacri. PSU : Trpo^e^rjKacn YZ. 

" i.e. in the sense that man is right-handed. 


motion ; and if it be placed on that which causes 
and is the origin of movement, it will either not be 
moved at all or with greater difficulty. The manner 
in which we step out also shows that the origin of 
movement is in the right side ; for all men put the 
left foot foremost, and, when standing, preferably 
place the left foot in front, unless they do otherwise 
accidentally. For they are moved, not by the foot 
which they put in front, but by that with which they 
step off; also they defend themselves with their 
right limb>. Therefore the right is the same in all ; 
for that from which the oria;in of movement is derived 
is the same in all and has its position by nature in the 
same place, and it is from the right that the origin 
of movement is derived. For this reason, too, the 
stromboid testaceans all have their shells on the 
right ; for they all move not in the direction of the 
spiral but in the opposite direction, the purple-fish, 
for example, and the trumpet-shell. Since, then, 
movement in all animals starts from the right, and 
the right moves in the same direction as the animal 
itself, they must all alike be right-sided." Now man 
more than any other animal has his left limbs de- 
tached, because of all animals he is most in accord- 
ance with nature, and the right is naturally better 
than the left and separated from it. Therefore the 
right is most right-sided in man. And since the right 
is differentiated, it is only reasonable that the left is 
less easily set in motion and most detached in man. 
Moreover the other principles,^ the superior and the 
front, are in man most in accord with nature and most 

* The dpxai here are the dLaardaeis of 701 b 19, 705 a 26, 
from the point of view of function rather than position. 



706 a 

V. OtS" /xei^ ovv TO di'oj Kal ro efjLTTpoadev 8t- 

(hpiaraiy Kaddnep rots dvdpojTTOis Kal roXg opvLcn, 

ravra jxev SliToSa [rcov he rerrdpajv rd Svo orjfxeia 

TOLS fi€V TTTepvyes ToZs 8e X^^P^^ '^^^ ^paxioves 

80 elcriv) . oaa 8' eVt ro avro ro TrpoaOev e;!^et Kal 
ro dvoj, rerpdrroha Kal TToXviroha Kal diroSa. 
KaXd) yap TToha jxepos inl Gruxeico Tre^co KivqrLKcp 
Kara roirov Kal yap ro 6Vo/xa eoiKauiv elXrj(f)€vai, 
aTTO rod irdSov ol noSes. eVta S' eVt ro avro 
ex^L TO rrpoadiov Kal ro ottlgOlov, olov rd re 
706 b /xaAciKrta Kal rd arpoi^L^wSr] rtov oarpaKoBepfiajv 
etp-qrai 8e Trepl avrdyv nporepov iv erepous. 

TpLwv 8* ovrcov roTTOJV, rod dvoj Kal jxeaov 
Kal Kdrco, rd jxev 8t7rc8a ro dvoj irpos ro rod 
oXov dvco ^x^i', Td Se rroXviroha tj dnoSa rrpos 
6 ro fxeoov, rd he (f)vrd npos ro Kdroj. a'inov 8' 
on rd fiev aKivqra, Tipos rrjv rpo(f>r)v Se ro dvoj, 
Tj Se rpo(f)rj eK rrjg y^?. to. Se rerpdrroha enl 
ro [Meaov, Kal rd TToXviroha Kal djToha, hid ro 
pLTj opOd elvai. rd he hiTToha Trpo? ro dvo) hid 

10 ro opSd elvai, fidXiora 8' o dv9pa>7TOS' /xaAtcrra 
ydp Kard ^volv earl hiTTOV?. evXoycos he Kal at 
dpxdi eloiv aTTO rovrwv rcov jxopicjjv rj jxev ydp 
dpx'^ TLiJLLOV, ro 8' dvo) rod Kara) Kal ro npoadev 
rod omoOev Kal ro he^iov rod dpiGrepod rijJLicorepov. 
KaXojs 8' ex€L Kal ro avdnaXiv Xeyeiv Trepl avrojv, 

<» The whole of man is " front," and his " front " is divided 
into superior and inferior ; in a quadruped only that part 
is " front " which is superior in man. 

" P.J. 681b U ff. ; H.A. 523 b 21 ff. 

" *Apxv has here the double meaning of "starting-point" 
and "centre of authority"; see note on De mot, anim, 
698b 1. 



V. Animals in which the superior and the front are 
differentiated, man, for example, and the birds, are 
bipeds (two of the four points being wings in birds, 
and hands and arms in man). But the animals in 
which the superior and the front are in the same 
position " are four-footed (quadrupeds), many-footed 
(polypods), and footless. By " foot " I mean the part 
that is at a point which has connexion with the ground 
and gives movement from place to place ; for the 
feet (TToSes) seem to have derived their name from 
the ground (-eSov). Some animals have their front 
and their back in the same position, for example the 
molluscs and the stromboid testaceans ; with these 
we have already dealt elsewhere.^ 

Now since there are three regions, the superior, 
the middle, and the inferior, bipeds have their 
superior part in a position corresponding to the 
superior region of the universe, polypods and footless 
animals in a position corresponding to the middle 
region, and plants in a position corresponding to the 
inferior region. The reason is that plants lack 
movement, and the superior part is situated with a 
view to nutriment, and their nutriment comes from 
the earth. Quadrupeds, polypods, and footless 
animals have their superior part in a position corre- 
sponding to the middle region because they are not 
erect ; bipeds have it in a position corresponding to 
the superior region because they are erect, especially 
man, the biped most in accordance with nature. And 
it is only reasonable that the origins <' should come 
from these parts ; for the origin is honourable, and 
the superior is more honourable than the inferior, and 
the front than the back, and the right than the left. 
It is also true if we reverse the proposition and assert 



15 COS Ota TO rag apxa? ev rovrois etvat Tavra 


VI. "On fxev ovu eK rcjv he^icov rj rrj? KLvqaecLs 
icTTLv apx'rjy (jiavepov eK rwv elpr^pidvajv. eVet 8* 
avdyKT] TTavTOS avvexovs, ov to [xev KivelTai 
TO 8' r]p€fji€Lj oXov hvvapiivov KiveZoOai iaTCOTOs 

20 daTepov, fj dpicfja) KiveiTai ivavTias Kiv^creigy etval 
TL Koivov Kad^ o Gvvex'Tj raur' eVrtv aWrjXoiSy 
KavTavO^ VTrdpx^LV ti]v apx^v rrjs eKarepov tcov 
ixepchv KLvriG€cx)s {ofjLOLOjg Se /cat Trjg ardaeajg), 
SrjXov QTiy^ KaO" OGas tcov XexOeiacov dvTiOeaecov 
tSta KLv-qGLS VTTapx^i tcjv dvTiKeipievcov jxepajv 

25 eKaTepo), rrdvTa Tavra kolvtjv dpx'rjv e;^et Kara? 
TTjv rcjjv elprjjjLevcjov jxepcov uvix^vgiv, Xdyco 8e rajv 
T€ Se^Lcbv Kal dpiarepojv /cat rcov dvoj /cat /carco 
/cat TOJV epLTTpoodev /cat rcbv omadev. Kara jxkv ovv 
to efXTTpoaOev /cat to OTTiuOev StdXrjifjLS ovk ean 
TOiavrrj rrepl to kivovv eavro, Sta to purjOevl 

30 (f>VGiKrjv VTrdpx^LV Kiviqoiv elg to OTTLcrdev, jLti^Se 
hiopiGpLOV e;^€tv to Kivovjievov Ka9* ov rrjv i(f>^ 
eKdrepa rovrcov fjiera^oXrjv TTOielraL' Kara he ro 
Se^LOV ye /cat dpiorrepov /cat to dvo) /cat ro Kdro) 
ecTTLV. 8to TOJV t^cpcxjv oua jiepeaiv dpyaviKols 
707 a XP^P-^^^ Trpoepx^raiy rfj fiev rod efnrpocrOev /cat 
OTTiadev Sta(f)opa ovk e;\;et SiajpLGfieva ravra, ralg 
8e AotTTat?, dpLcfjorepais p-^v, Tjporepa 8e rfj Kara 
TO Se^Lov Kal dpiGrepov SLopL(l,ovarj, 8ta to ttjv 

* drjXov 6ti (Leon, manifestum est quod, etc.) : drfKovbri libri. 
2 Kara P Leon. : cm. ceteri. 

" i.e. the three pairs of " dimensions " (704 b 19). 


that, because the origins are situated in these parts, 
they are therefore more honourable than the opposite 

VI. It is clear, then, from what has been said that 
the origin of movement is on the right. Now in 
anything continuous of which part is in motion and 
part at rest (the whole being able to move while one 
part stands still), there must be, at the point where 
both parts move in opposite movements, something 
common to both which makes these parts continuous 
with one another (and at this point must be situated 
the origin of the movement of each of these parts, 
and likewise also of their immobility) : it is evident, 
therefore, that in respect of whichever of the above- 
mentioned contraries" the individual movement of 
each of the opposite parts takes place, there is in 
all these cases a common origin of movement by 
reason of the interconnexion of the said parts, namely, 
of the right and the left, the superior and the inferior, 
the front and the back. The differentiation accord- 
ing to front and back is not one which applies to 
that which moves itself, because nothing possesses a 
natural movement backwards nor has the moving 
animal any distinction in accordance with which it 
can make a change from place to place in each of 
these two directions ^ ; but there is a differentiation 
of right and left, superior and inferior. All animals, 
therefore, which progress by the employment of in- 
strumental parts have these parts differentiated, not 
by the distinction between front and back, but by the 
other two pairs, first, by the distinction of right and 
left (for this must immediately exist where there are 

^ In other words an animal cannot divide itself into two 
parts, one of which goes forwards and the other backwards. 



/xev €v TOLs ovoLu €V0€aj£ avayKaiov elvai vtt- 
5 dpx^iVy rrjv S' iv rots TerrapciL Trpojrois. 

'E77-et OVV TO T€ CLVOJ Kal /CCtTCO Kal TO he^Lov Kal 

dpLGTepov rfj avrfj dpxfj Kal KOLvfj (jvv^prrjrai TTpos 
avrd [Xiyoj Se ravriqv rr]v rrjs KLvrjaeajs Kvptav), Set 
8' iv aTTavTi ro) piiWovTi Kara rpoirov TTOLelcrOaL 
TTjv d(j)^ eKdarov KiviqGiv ojpta^at ttojs Kal rerd- 
10 xdoLL rals dTTOGrdaeoL rals irpos rds p-qOetoas 
dpxds, rds re avrioroixovs Kal rag (TUGtolxovs 
Tcov iv rot? fiepeGL tovtols, to tcov Ae;^^etcrajv 
KLv-qaecov diracrajv atriov (avrr] 8' iorlv dcji" rjs 


dpLGT€pov KLvrjcrlg ioriv, opioiiDS 8e Kal r) rod dvoj 
15 Kal Kdrcx)), ravT-qv 8'^ ^X^'-^ eKdoro) fj irapaTrXiqGLOJS 

€X^l'^ TTpos €KduTr]V TCOV iv Tols pTjOeiGL jji€p€GiV 

dpxcJf^v, VII. SrjXov OVV (hg 7] piovois ri pLdXicrra 
TOVTOLs VTrdpx^f' Tchv t,a)cov T] Kara tottov KLvrjons, 
d hvulv t) rerrapGi rroielrai Grjfielois ttjv Kara 
TOTTOV pb€TafioXriv . OJGT eTTel Gx^Sov TOLS ivaip^oLs 
20 TOVTO pidXiGTa GV/ji^e^-qKe , (jyavepov otl TrXeioGi 


ivalfiajv t,a)cov, Kal et tl TeTTapGi Gr]iJL€iOLS KLvelGdai 
Tii^vKe jjLovov, dvayKalov tovt elvai evaip,ov. 

'OpLoXoyel 8e toIs Aex^etcrt /cat to. Gvp^^alvovTa 

rrepl Ta ^wa. tcov jikv yap ivaipLcuv ovhev els 

25 TrXeio) hiaipovfJLevov hvvaTai i,rjv ovOeva ;)(/3ovov 

1 5' PUZ : om. SY. a ^^ft z : om. cet. 

<» i.e. the distinction of superior and inferior. 

^ Namely, the soul situated in the heart (Mich.). 

* The lef^s move in pairs, either the front and back legs 
on the same side together, or the front leg on one side with 
the back leg on the other (c/. 704 b 7). 


two things), and, secondly, by the distinction which 
must arise as soon as there are four things. ° 

Since, then, the superior and the inferior, and the 
right and the left are connected with one another by 
the same common origin (and by this I mean that 
which controls their movement ^), and since in any- 
thing which is to carry out the movement of each 
part properly the cause of all the said movements 
must be somehow defined and arranged at the right 
distance in relation to the said origins, namely,* 
those in the limbs, which are in pairs opposite or 
diagonal to one another,*' (and the cause of their 
movement is the common origin from which the 
movement of left and right and likewise of superior 
and inferior in the animal's limbs is derived), and 
since this origin must in each animal be at a point 
where it is in more or less the same relation to each 
of the origins in the said parts,*^ O'^-''^-'--) it is, therefore, 
clear that movement from place to place belongs 
either solely or chiefly to those animals which make 
their change of place by means of two or four points. 
And so, since this condition occurs almost exclusively 
in red-blooded animals, it is clear that no red-blooded 
animal can move by means of more than four points, 
and if an animal is so constituted by nature as to 
move by means of four points only, it must neces- 
sarily be red-blooded. 

What actually occurs in animals is also in agree- 
ment with the above statement. For no red-blooded 
animal can live for any time worth mentioning if it be 

** There are two kinds of dpxai in, e.g., a quadruped, (a) 
those in each of the four legs and (6) the central dpxv in the 
heart ; the former must each be approximately equidistant 
from the latter. 



707a , , . _ , , 

p rt 

COS" €L7T€iV, rr]g re Kara rorrov Kivqueois , Kau rjv 
eKLvelro cruvep^e? oV /cat /xi^ dujpiqjxivov, ov hvvarai 
KOLVCoveiv rojv 8* dvaLfiajv re Kal ttoXvttoScdv evia 
Siaipovfieva Svvarai t,rjv ttoXvv xP^'^^^ eKaarcp 
rwv pLepojv, Kal KtveZadai rrjv avrr)V TJvnep Kal 
80 TTplv SiaipeOrjvai Kcvrjcnv, olov at re KaXovfievat 
GKoXoTTevhpai Kal d'AAa rwv evrojicov Kal TrpofjirjKOJv' 
TTOLvrajv yap rovrcov Kal ro oTnadev fiepos inl 
107 b ravro rroieZrai rrjV rropeiav rep epLTrpoodev. atriov 
he rod SLaipovfieva l,rjv on, KaOdirep dv el ri 
avvexes eK noXXcnv etrj t,ojojv GvyKeiiJievov, ovrcog 
eKaarov avrcov ovvecrri^Kev . <^avep6v he rovro eK 
rcov TTporepov elprjpievcov, Stort rovrov ex^c rov 

5 rpOTTOV. 

Aval yap t) rerrapui (j-qp^eiois 7Te(f)VKe KtveiGdaL 
rd fJidXicrra crvveariqKora Kard cfyvGiv, o/xotws" he 
Kal oaa rojv evaipiojv dnohd ecrnv. Kal ydp ravra 
Kivelrai rerrapGi GrjjiieLOi?, 8t' wv rrjv klvtjglv 
TTOielr ai. hvul ydp ;\;pc(j/xera Trpoepxerat Kajx- 

10 TTals' ro ydp he^Lov Kal dpiarepov Kal ro TTpoaBiov 
Kal ottlgOlov ev ro) TrXdrei eGrlv ev eKarepa rfj 
KafjLTrfj avrols, ev p.ev rep rrpos rrjv Ke<f)aXr]v 
fjLepei ro Trpoodiov Giqp.elov he^iov re Kal dpi- 
Grepov, ev he rep Trpos rrjv ovpdv rd OTTLGdca 
Giqp.eZa. hoKeZ he hvoZv G-q/jLeloLV KLveZGOai, rfj r' 
epLTTpoGOev d(f)fj Kal rfj • varepov. acrtov 8' on 

15 Grevov Kard TrXdros eGrlv, eirel Kal ev rovroig ro 
he^Lov rjyeZraL, Kal dvra7Tohiha)GL Kard ro OTTiGdev, 
ojGTtep ev roZs rerpdnoGiv. rdJv he Kai^ixjjeojv 
alnov ro (irJKOs- wGrrep ydp ol fxaKpol rwv dv- 
dpcoTTOJv Xophol ^ahi^ovGi, Kal rod he^iov Wfiov 

" Centipedes. 


divided into several parts, and can no longer partake 
of the motion from place to place whereby it moved 
while it was still continuous and undivided. On the 
other hand, some of the bloodless animals and poly- 
pods can, when they are divided, live in each of 
these parts for a considerable time and move with 
the same motion as before they were divided, the so- 
called scolopendrae,"for example, and other elongated 
insects ; for the hinder part of all these continues to 
progress in the same direction as the fore-part. The 
reason why they live when they are divided is that 
each of them consists as it were of a continuous body 
made up of many animals. And the reason why they 
are of this kind is clear from what has been said above. 
Animals which are constituted most in accordance 
with nature naturally move by means of two or four 
points, and likewise also those among the red-blooded 
animals which are footless ; for they too move at four 
points and so effect locomotion. For they progress 
by means of two bends ; for in each of their bends 
there is a right and a left, a front and a back in 
their breadth — a front point on the right and another 
on the left in the part towards the head, and the two 
hinder points in the part towards the tail. They 
appear to move at two points only, namely, the points 
of contact with the ground in front and behind. The 
reason for this is that they are narrow in breadth ; 
for in these animals too, as in the quadrupeds, the 
right leads the way and sets up a corresponding move- 
ment behind. The reason of their bendings is their 
length; for just as tall men walk with their backs 
hollowed ^ and, while their right shoulder leads the 

* Xopoos is the opposite of kv(I>6s^ hunchbacked (Hippocr. 
Fract. 763). 



707b , , ' n ( / V ' X -, , » 

€L5 TO TTpoaUev riyoviievov to apiOTepov La)(Lov et? 

20 TOVTTLodeV fxdXXoV OLTTOKXlveLy /Cttt TO flCGOV KOiXoV 

yiveTai koI XopSov, ovtoj SeX voetv Kal tovs 6(f)€Ls 
KLVovfievovs errt ttj yfj AopSou?. o-qfielov 8' otl 
oiJLOLWS KivovvTai Tols TeTpoLTTOGLv ' €v fMcpet yap 
fX€Ta^dXXovai to koIXov Kal to KvpTov. oTav 
yap TToXiv TO apiOTepov tcjjv rrpooOiajv rjyi^oyjTai, 

25 e^ evavTias ttoXlv to koZXov ytVerat- to yap he^iov 
evTOS TToXiv yiveTai. arj/jLeXov Se^iov Trpoodiov 
€(/)' ov A, apiGTepov icf)^ ov B, ottloOlov Se^Lov icj)* 
ov r, apiGTepov i(f)^ ov A. 

OvTCo 8e KLvovvTai TcJou fi€v ;)(ep(7accov ol o^eis, 
Tchv S' ivvSpcov at iyx^Xeis Kal ol yoyypoi Kal at 

30 fJivpaivaL, Kal tcjv d'AAcuv ooa e;^et Tr]v iJLop(f)rjP 
6(f)LajS€(JT€pav. ttXtjv evia fxev tojv ivvSpa>v tcjv 
TOLOVTWV ovSev €X^f' TTTepvyiov , olov at pLvpaivai, 
708 a aAAa XPV'^^^ '^fi Go-XaTTTj axjTrep ol o^eLs ttj yfj 
Kal TTJ daXaTTT) [veovui yap ol oc^eig o/xotcus" 
Kal OTav KLvcjVTai inl ttjs y^s)' to, 8e 8u' ex^t 
TTTepvyia pLovov, olov ol t€ yoyypoi Kal at iy- 
XeXeig Kal ylvos tl KeGTpeo)v, 6i yivovTai iv 
6 TTJ XifJivrj TTJ iv Stoats'. Kal Sta tovto Tals 

KapiTTals iXoLTTOOL KiVOVVTai iv Tip VypO) 7) iv TTJ 

yfj TO, t,rjv elojOoTa iv Tfj yfj, KadaTrep to tojv 
iyxiXecov yevos. ol 8e Svo TTTcpvy la exovTes tcov 

K^GTpioJV Tfj KapLvfj OLVLad^OVOLV iv TO) VypO) TO, 

rerrapa orjpieZa. VI 11. rot? 8' 6cf)€GLV aiTLov ttjs 

10 0,7708 ta? TO T€ TTjV (f)VGLV piTjOiv TTOielv /XClTT^l', 

" On the Boeotian coast of the Corinthian Gulf, the Tipha 
of Pans. ix. 8i>. 3. 

'' i.e. two of its "points" are fins and the other two are 
made by bends. 


way forward, their left hip indines towards the rear 
and the middle of the body becomes concave and 
hollow, so we must suppose that snakes too move 
upon the ground with their backs hollowed. And 
that they move in the same manner as quadrupeds 
is shown by the fact that they change the concave 
into the convex and the convex into the concave. 
For when the left forward point is again leading 
the way, the concavity comes in turn on the other 
side, for the right again becomes the inner. Let 
the front point on the right be A, and that on the 

left B, and the rear point on the right C, and that on 
the left D. 

This is the way that snakes move as land-animals, 
and eels, conger-eels and lampreys and all the 
other snake-like creatures as water-animals. Some 
water-animals, however, of this class, lampreys for 
example, have no fin and use the sea as snakes 
use both the sea and the land ; for snakes swim in 
just the same manner as when they move on land. 
Others have two fins only, conger-eels for example, 
and ordinary eels and a species of mullet which occurs 
in the lake at Siphae." For this reason too those 
which are accustomed to live on land, the eels for 
example, move with fewer bends in the water than 
on dry land. The kind of mullet which has only two 
fins makes up the number of four points in the water 
by its bends. ^ VIII. The reason why snakes are 
footless is, first, that nature creates nothing without 



708a ,>,. ^ , , ^ V ' nw 

aAAa rraura Trpos ro apiorov aTTopAeTrovGav eKaorcp 
rcbv ivScxofiei'ojv, hiaaaj^ovuav iKaarov rrjv ISiav 
cvuiav Kal ro ri rjv avrco ctvaf en Se kol to irpo- 
repov rjpLiv elpripLevov , to tcov ivaipicov pLrfOkv olov 
r' elvai mXeiooi KiveZuBaL OTjixeioig t] Terrapcrtv. 
eK TOVTCDV yap (f>av€p6v otl tojv evaipicov ooa Kara 

15 to fjirJKOs aavixpLerpd eVrt TTpos ttjv dXXrjv rod 
a(x)}jiaros (f)V(JLV, Kaddnep ol 6<j)€is, ovOev avrcov 
OLOV 6^ VTTOTTovv etvai. irXeiovs fikv yap rerrdpcov 
ovx olov re avrd TroSa? ^x^tv (dvaL[jLa yap dv '^v), 
exovra §€ Suo TTohas rj rerrapas ox^^ov rjv dv 
aKLvrjTa TrdpLTrav ovro) ^pahelav dvayKalov etvai 

20 Kal dvcix^eXrj rrfv Kiviqcjiv. 

^Arrav he ro VTronovv e^ dvdyK7]s dpriovs e;\;ei 
Tov? TToSas" ocra piev yap dXoet ;YPc6/xeva jjlovov 
TToielrai ttjv Kara tottov jjiera^oXrjv , ovOev ttoScov 
TTpos y€ rrjV roiavT'qv heZrai KLvrjOLV doa he 
Xpy]Tai piev dXaei, prnj eon 8' avroZs avrdpKrjs 

25 avTT] rj KLvrjGis dXXd Kal Trope lag Trpocrheovrai, hij- 
Xov d)S roXg piev ^eXrtov roZs S' (dXXojs^ oAcos" 
dhdvarov^ TTopeveoOai. [Stort irdv t,a)OV dvayKaZov 
dpriovs ^X^^^ rovs TroSa?.]* ovarjg yap rrjg 
roLavr7]£ piera^oXrjs Kara piepos, oAA' ovk ddpocp 
rravrl rep (JcopLart KaOdrrep rrjs aXoreajg, dvayKaZov 

80 ian roZs piev pieveiv piera^aXXovrcov rcov TTohwv 
roZs he KLveZodaiy Kal roZg dvriKeipievoLs rovrcov 
TToieZv eKdrepov, piera^dXXov 0,77-0 rcbv KcvovpLevcuv 
6771 rd pLevovra ro ^dpos. hiOTrep ovre rpial ptev 

* <(!i\Xws> SXcjs dovparov] oXws ddouaTou <(!i\Xws> Farquharson. 
■ di6Tt . . . TTudas om. PwSU: tanquam glossema del. Jaeger. 

" Mich.'s explanation of this passage is that certain poly- 
pods, which can walk with an uneven number of legs (c/. 


a purpose but always with a view to what is best for 
each thing within the bounds of possibiHty, preserv- 
ing the particular essence and purpose of each ; and, 
secondly, as we have already said, because no red- 
blooded animal can move by means of more than four 
points. It is clear from this that all red-blooded 
animals whose length is out of proportion to the rest 
of their bodily constitution, like the snakes, can none 
of them have feet ; for they cannot have more than 
four feet (for if they had, they would be bloodless), 
whereas, if they had two or four feet, they would be 
practically incapable of any movement at all, so slow 
and useless would their movement necessarily be. 

Every animal which has feet must necessarily have 
an even number of feet ; for those which move from 
place to place by jumping only do not require feet 
(at least not for this movement), while those which 
jump but do not find this mode of locomotion suffi- 
cient by itself and need to walk also, must clearly 
either progress better with an even number of legs 
or else cannot otherwise progress at all.^ For since 
this kind of change from place to place is carried out 
by a part and not, like jumping, with the whole of 
the body at once, some of the feet during the change 
of position must remain at rest while others are in 
motion, and the animal must rest and move ^^'ith 
opposite legs, transferring the weight from the legs 
in motion to those at rest. Hence no animal can 

708b 5 ff.), would walk better with an even number; quad- 
rupeds and bipeds, on the other hand, cannot walk at all with 
an uneven number of legs. Farquharson's insertion of dXXws 
seems therefore a certain emendation : the omission of ctWws, 
however, in our mss. would be better accounted for if it is 
inserted before 6'Xws rather than before iropeveadai. 

R 507 


708 h ovOev oud^ eVt^ xpcofieuov ^ahit^eiv olov re* to fxev 
yap ovOev oXcos VTToarrjpia e;^et e^* a> ro rod 
awfxarog e^et ^dpos, ro Se Kara tyjv irlpav 
avrlOeaiv fxovrjv, cxidr dvayKolov avro ovrojs 
eTTLX^ipovv KLveioOai niTTreiv. oaa 8e ttoAuttoSci 
6 eoTLv, OLOV at cr/<:oAo77ei'Spat, tovtols Svvarov fxev 
Kai arro TTepcrrajv ttoScqv TTopelav yivecrdai, Kaddirep 
(f)aLV€TaL TTOLovfieva Kal vvv, dv ns avrajv eva 

TT'qpCOOrj T(JL)V TTohcbv, hid TO TTyP' TCJJV dvTlOToi')(WV 

TToScuv KoXo^axJLV Idodai rat Xoltto) ttXtJOcl tojv 
i(j)^ e/carepa ttoScov ytVerat yap rovroi? olov 

10 e(f>eX^Ls rod TreTT-qpojiJievov piopLov rolg dXXoLs, 
dXX ov ^dhiGLs. OX) pLTjv dXXd (f^avepov otl ^IXtlov 
dv Kal ravra ttololto ttjv pLera^oXrjV dprtov? 
exovra rovs TToSag, /cat pLrjdevos iXXeiTTovTOS} aAA' 
avTiGToixovs e^ovra rovs nohas' ovtoj yap (dv^^ 
avrcJov dvLord^etv re SvvaLTO^ ro ^dpo? Kal pLTj 

15 raXavreveiv iirl Odrepa pidXXoVy el dvriorotxo. 
epeicr/xar' €';^ot Kal pirj Kevrjv rrjv irepav x^P^^ 
rojv* dvTLK€Lp,€va)v. 7Tpo^aLV€L 8* d^' eKarepov 
TOJV piepcbv ivaXXd^ ro TTopevopbevov ovrco yap 
ets" ravro rep i^ oiPXV^ o)(ripiarL y ever at rj Kard- 

20 "On puev ovv dprcovs e^et rovs vroSa? Trdvra, 
Kal Std TtV air lav, e'lprjrai' IX. ort 8' el pLr]6ev 
'qv rjpepLOVV, ovk dv rjv Kdpujjis oi3S' evOuvcns, eK 
rcbvSe SijXov. eon ydp Kdpufji? ptev rj e^ evdeos t] 
els TTeptcfjepe? t) els ycovlav piera^oXrj, evdwcrts 
8' Tj eK darepov rovrojv els ev6u. ev aTrdoais 8e 

25 rat? elp-qpLevats piera^oXaZs avdyKt] irpos €v oiqpielov 

^ oUre Tpicrl fi^u ovdev ovd' ivl Jaeger: ovo^ (ovd^ om. PYZ) 
rpicrl fi^v ovdkv ovdevl libri. ^ hv add. Jaeger. 



walk using either three legs or one leg ; for if it uses 
one leg it has absolutely no support on which it is to 
rest the weight of the body, and if it uses three it will 
rest it on a pair of opposite legs, so that, if it attempts 
to move thus, it necessarily falls. Polypods, however, 
for instance the scolopendrae, can achieve progression 
with an odd number of legs, as they can be immediately 
seen to do if you mutilate one of their feet, because 
the maiming of some of the feet in the opposing rows 
is compensated by the greater number of feet still 
remaining on either side ; the result is that the 
maimed leg is as it were dragged along by the others, 
and the animal does not walk properly. How^ever, 
it is clear that these maimed animals would achieve 
the change of position better if they had an even 
number of feet, that is, if none were lacking and they 
had all the feet in the corresponding rows ; for then 
they would be able to distribute their weight evenly 
and would not sway to one side, if they had corre- 
sponding supports on each side and had not one space 
in the opposite rows devoid of a leg. An animal, 
then, when it walks progresses by means of each of 
its limbs alternately ; for thus its state is restored so 
as to be identical with its original form. 

It has now been established that all animals have 
an even number of feet, and the reason for this has 
been stated. IX. That, if nothing were at rest, there 
could be no bending or straightening is clear from the 
following considerations. Bending is the change from 
what is straight to what is curved or angular; straighten- 
ing is the change of either of these to what is straight. 
In all the above changes the bending or straightening 

8vuaLTo scripsi : 5iVarat Z : dvi/aLUTo ceteri. 
* Tr]v ante runf add. Z. 



Kaynjjeajs ye jLti^ ovar}? ovr av iropela ovre vevais 

ovT€ TTTTJGLg tJv . TO, [xev yoLp VTTOTToSa eTTeihr] eV 

eKarepcp rcbv dvrLK€LfjL€vojv crKeXcbv iv fxepei tararat 

Kal TO ^dpos Igx^l, dvayKolov daripov npo- 

30 ^alvovTOS Oarepov TTOieladaL KaiJLifjLV. tea re yap 

7re(f)VKev e^^iv toj fjnqKei to. dvTLGroL)(a Ka)Xa, Kal 

opdov Set elvai to v^€Gt6s rep ^dp€L, olov Kdderov 

77/30? rr]v yrjv. orav he rrpo^aivr], yiverai r) 

709 a vTroreivovGa Kal hwafievr] ro pievov pieyedos Kal 

TTjv pLera^v. i-TTel 8' Lcra rd /ccoAa, dvdyKY] Kdpbipai 

TO piivov, t) €V TO) yovari t) iv rfj Kdpupei, olov 

et TL dyovarov etrj rcov ^ahit^ovrcov. GrjpieZov 8' 

5 ort ovr cog '^X^^' ^^ 7^9 '^^^ ^^ yfi^ /SaSi^ot irapd 

TOLXpv, r) ypa(f)opL6vrj eorai ovk evdela dXXd GKoAta, 

Sid ro iXdrroj puev KdpnTrovros yiveoOai rrjv 

ypa^oix€vr]v, pLel^co 8' lorapievov Kal l^aipovros. 

'Ei'8e;^eTat piivroi KLveladaL Kal pLrj exovros /ca/x- 

TTrjv rod OKeXovg, coCTTrep rd Traihia eprrovuLV. Kal 

10 TTepl rojv iXecfidi'raji' 6 TraAatos" 17^' Aoyo? roiovros, 

OVK dXr]Orjg div. Kiveirai 8e Kal rd roiavra 

Kdpupeojg yivopLevrjs iv ralg (hpLOTrXdrais 7) rols 

lax^oig. aAA' opdov ovhev hvvair* dv TTopevdyjvaL 

GVV€xd)9 Kal dG(f)aXa)s, Kiviqdeiy] 8' dv olov iv 

rals TTaXaiorpais ol 8ta rr^? Kovea^s rrpo'Covres irrl 

rcbv yovdrcov. ttoXv ydp rd dvco piipog, ojore 

1 ej/ 777 libri : locus corruptus et lacuna mutilatus, 

«» It does not actually do so because it is not long enough 
to reach the ground : and so, as is explained below, the other 
leg must be bent to enable it to do so. 

*" Ai'i'afXLs in mathematics is used of a "power," generally 
the second power, i.e. the square of a number : similarly in 
geometry duvafiis and bvvaimi are used of the figure which 



must necessarily be relative to a single point. Further, 
if there were no bending, there would be no walking 
or swimming or flying. For since animals with feet 
stand and rest their weight alternately on each of 
their two opposite legs, as one leg advances the other 
must necessarily be bent. For the corresponding 
legs on either side are naturally equal in length, and 
the leg which supports the weight must be straight, 
at right angles, as it were, to the ground. But when 
a leg advances, it is assuming the position of the side 
subtending a right angle, ° the square upon which 
equals the squares ^ on the side which is at rest and 
the hne between the two legs ; but since the legs 
are equal, the leg which is at rest must bend either 
at the knee or, in any kneeless animal that walks, at 
the joint. That this is so is shown by the fact that 
if a man were to walk on the ground alongside a wall 
[with a reed dipped in ink attached to his head],^ 
the Hne traced [by the reed] would not be straight 
but zigzag, because it goes lower when he bends and 
higher when he stands upright and raises himself. 

It is possible, however, to move even if the leg has 
no bend in it, as happens when children crawl. (The 
old account attributed such motion to elephants, but 
it is untrue.) Movement of this kind takes place 
through a bending in the shoulders or hips. But no 
creature could walk erect in this way continuously 
and safely, but could only move like those who drag 
themselves forward through the dust in the wrestling- 
school on their knees. For the upper portion of the 

can be formed by constructing squares on the side of, e.g. a 

* The text here is corrupt and something has fallen out in 
all our Mss. : the words here bracketed are supplied from the 
explanation given by Mich. 



709 a 

16 Set fiaKpov elvai to KihXov el he rovro, KoifiipLV 

dvayKOLOV elvau. eirel yap earrjKe rrpos opO'qv, 

16 b et aKapLTTTOV eorai ro Ktvovpievov et? to irpoadev^ 

Tj KaTaTTeoelTai eXaTTOVog Trjg opdrjs yivopieviqs , rj 

ov TTpo^rjGeTai. el yap opOov ovtos OaTepov UKeXovs 

OoLTepov ecrrat 7Tpo^e^r]K6s, p^ell^ov ecrrat, lgov 6v 

hvvrjCjeTai yap tovto to t rfpepiovv Kac ttjv vtto- 

20 Teivovoav . dvdyKrj dpa Kap^vTeadai to Trpo'Cov, Kal 
Kapupav a/xa eKTeiveiv OaTepov, eKKXiveiv re /cat 8ta- 
^ep7]KevaL Kal cVt ttjs KaOeTOV pieveiv IcroaKeXes 
yap yiveTai Tpiycxjvov ra /ccoAa, Kal r) Kecf)aXrj yive- 
rat KaTWTepov, oTav KaOeTos fj e^' rjs ^e^riKev. 

25 To, 8' drroha Ta piev KvpiaivovTa TTpoepxeTau 
{tovto 8e Slttw^ GvpL^aivei' to. p^ev yap eirl 
TTJg yTJs", Kaddirep ol 6<j>eis, rds KapLirdg TToieZ- 
rat, TO. 8' els to avco, u)GTTep at KapLTrat), rj 8e 
KVpiaVGlS KapLTT-q eGTlV TO, 8' IXvGTTaGeL xp^H-^^OL, 

80 KaOdirep Ta KaXovpieva yrjs evTepa Kal ^ScAAat. 
TavTa yap to) piev rjyoupieva) TrpoepxeTac, to 8e 
XoLTTOv crdjpia Trdv rrpos tovto Gvvdyovai, Kal tov- 


(f>avep6v 8' OTt et pirj at Svo ttjs pads pLel^ovs rjGav, 

^ el dKa/xTTTOu iarai t6 Kivov/xefov els t6 irpbcrdev om. PSU 
Bekker : e^ et irpbadev om. Z. 

<• Let AB be the stationary leg and 
AC the advanced \tg^ which are by 
hypothesis of equal length. If the right- 
angled triangle ABD is constructed its 
hypotenuse AD must be longer than 


body is large, and therefore the leg must be long ; and 
if this is so, there must necessarily be a bending. For 
since a standing position is perpendicular, the leg which 
is moved forward, if it is to be unbent, will either fall 
as the ritcht ano-le becomes less, or else it will not ad- 
vance at all ; for if, while one leg is at right angles, the 
other is advanced, the advanced leg will be greater and 
at the same time equal ; for it will be equal to the leg 
which is at rest and also to the side subtending the 
riffht ang-le.^ The advancinfj leff must therefore be 
bent, and the animal, as it bends it, must at the same 
time stretch the other leg and lean forward and make 
a stride and remain in the perpendicular ; for the legs 
form an isosceles triangle and the head becomes 
lower when it is perpendicular to the base of the 

Of animals which are footless, some advance with 
an undulating motion — this can be of two kinds, for 
some animals, for example snakes, make their bends 
on the ground, while others, for instance caterpillars, 
make them upwards — and undulation is bending. 
Others move by crawling, like the earthworms and 
leeches ; for these advance ^\^th one part leading the 
way, and then draw up all the rest of their body to it, 
and in this manner make the change from place to 
place. It is plain that, if the two lines which they 

^ When the stride has been completed the result is an 
isosceles triangle formed by the two legs and the ground ; the 
head, which is necessarily lower than when the legs were 
together, is perpendicularly above the base. 



709 b oi)K av iSvvavro KiveLodai ra Kvyiaivovra tojv 
L,a)Cx)v. iKradeiorj? yap rij^ KafiTrrj?, el L<jr]v 
KareXx^v, ovdev av Trpoj^eo-av vvv 8' virep^aXXei 
iKTaOelaay Kal rjpefjLTJGavros tovtov CTrayet to 


'Ev TTaoais he rat? XexOeicrais pLera^oXalsro klvov- 
6 fjuevov ore jxev eKTewojjLevov els evdv TTpoepx^rai, 
ore 8e avyKajJLTrrofievov, rot? jjiev 'qyovpievois 
[xepecrw evdv yivofievoVy roZs 8* erropLevoLS orvy 
KapLTTrov. TTOielraL 8e /cat ra aWopieva Trdvra 
Kapufjiv ev raj vrroKeipieva) pLepei rod crwpiaros, 
Kal rovrov rov rporrov e^ovra aXXerai. Kal ra 
TTeropLeva 8e Kal ra veovra, ra pikv ras Trrepvyas 

10 evOvvovra Kal KapLTrrovra Trerarat, ra Se rot? 
TTrepvyiois, Kal rovrcov ra piev rerrapat ra he 
hvaiv, ocra rrpopnqKeorepa rrjv pLop^-qv, axnrep ro 
rcov eyx^Xeojv yevos' rrjv 8e Xoltttjv Kivqoiv avrl 
rcjv hvo TTrepvyicov ra> Xoittw rod Gojpiaros KapLTrro- 
pieva vet, KadaTrep eipr^rai nporepov. ol he rrXareZs 

15 TcDv IxOvcov rfj puev ro) TrXdrei xpoJ^TOLi rod crco/xaro? 
avrl TTrepvylajv, rfj he Trrepvyiois hvuiv. ra he 
TTapiTTav TrXarea, KadaTrep 6 ^dros, avroZs rots 
Trrepvyiois Kal rats euxdrais rod acopiaros irepi- 
(f)epeLaLs evOvvovra Kal Kdpiirrovra TTOieZrai rrjv 

^ X. *A7Top7Jcrete 8' av ns locos ttcos Kivodvrac 
rerrapGL (jTjpLeloLs ol opvideSyTj neropLevoL ^ rropevo- 
pLevoLy cos elpripLevov on Trdvra ra evaip-a KiveZrai 
rerrapatv. ovk elp-qr ai he, aAA' on ov TrXeiooLV. 
ov piTjv dAA' ovr^ av TrereaOat hvvaivro d<f)aLpe- 

" The bend is represented as two lines forming an angle ; 


form were not greater than the one," movement would 
be impossible for animals which advance by undula- 
tions. For, when the bend is extended, they would 
not have made any advance, if it subtended an equal 
Hne ; whereas, in fact, it is longer when it is extended, 
and then, when this part has come to a standstill, 
the animal draws up the rest. 

In all the above-mentioned changes that which 
moves advances by first extending itself straight out 
and then curving itself — straightening itself out with 
its leading parts and curving itself in the parts which 
follow. All animals, too, which jump make a bend 
in the lower part of their body and jump in this 
manner. Animals also which fly and those which 
swim, fly by straightening and bending their wings 
and swim with their fins, some fish having four 
fins and others, namely those which are of a more 
elongated form (eels for example), having two fins. 
The latter accomplish the rest of their movement 
by bending themselves in the rest of their body, as a 
substitute for the second pair of fins, as has already 
been said. Flat-fish use their two fins, and the flat 
part of their body instead of the second pair. Fish 
that are entirely flat, like the ray, manage to swim by 
using their actual fins and the outer periphery of their 
body, which they alternately straighten and bend. 

X. A question might perhaps be asked as to how 
birds, whether flying or walking, can move at four 
points, in view of the statement that " all red-blooded 
animals move at four points." But this is not exactly 
what we stated ; what we said was " at not more than 
four points." However, they could not fly if their 

tb.ese two lines together must be longer than the line which 
subtends their angle. 

r2 515 


709 b ^ „ , ^ , 

uevrcov tojv kcoAcjjv ovre Tropeveouai rcov Trrepvyajv 

25 a<j)aLpeBei<7(i)v, eirei ouS' avdpojTTOs ^ahit^ei fjurj 
Kivcjv Tovg MfjLov?. dXXoL Trdvra ye, KaOdnep 
e'lprjraL, Kapi^ei Koi iKraaet TTOielrai ttjv fiera- 
^oXiqv' (iTjavra ydp €ls to vTroKeifxevov fi^xpt' tlvos 
olovel avvvTTeXKov^ Trpoepx^rai, cocrr' dvayKolov, 
el fjLTj Kal KOT* dXXo fiopiov ytVerat rj Kdjjupcs, dXX* 

80 odev ye rq ^PXV ''"ots" jLtev oXoirripois rod Trrepov, 
TOt? 8' opvLGi rrjs nripvyos, rot? 8* ctAAots" rod 
dvdXoyov fxoplov, Kaddrrep rols lxOvglv. rots' S', 
a)G7T€p ol 6cf}€L9, iv roZs /ca/XTrats" rod (jcvfiaros 

710 a iorriv rj dpx'T] rrjg Kdpupeois. ro S' odpoTTvyiov icrn 

rots TTrrjvoLS Trpos ro Karevdvveiv rrjv Trrrjocv, 
Kaddnep rd TrrjhdXia roZs ttXolois. dvayKoiov 8e 
KOI ravra eV rfj Trpoa^vGei KdfXTrreiv. hiorrep rd 
5 re oXonrepa Kal rojv GX^^OTrripojv ols ro ovponvyiov 
d(j)va)£ e%et 77^6? rrjv elp-qiievrjv XP'^^^^> otov rolg re 
racpg Kal roXg dXeKrpvooc Kal oAcos" rot? jjltj Trrrjn- 
Kots, ovK evdvTTopovGiv rwv fxev ydp oXorrrepajv 
dnXcog ovdev e^et ovpoTTvyiov, (Lare KaOdirep d- 
rnqhaXov nXolov (j)eperai, Kal ottov dv rvxj] eKaarov 
10 avrojv TrpoGTTCTTrei, ofioLOJS rd re KoXeonrepa, 
otov KdvQapoi Kal pL-qXoXovO ai, Kal rd dveXvrpa, 
otov jxeXirraL Kal G(f)7]Kes. Kal rols fir] TrnqriKoZs 
dxpeZov rd ovpoTTvyiov eGriv, otov rols re rropcjiv- 
pLa>Gi Kal epcahiols Kal TraGi rols rrXatrols' aAA' 
dvrl rod ovporrvyiov neravrac rovs TToSas diro- 

^ olovel avvvireiKOv Z : olov ei's virelKOV ceteri. 

* Lit. " creatures with undivided wings." (The Greek 
here has different words for the wings of insects and those 
of birds.) 

* Lit. creatures with cloven wings {i.e. made up of feathers) 
as opposed to insects which have undivided wings. 



legs were taken from them, or walk if their wings 
were taken from them, just as a man cannot walk 
without moving his shoulders to some extent. All 
things, as has been said, make their change of position 
by bending and stretching ; for they all progress 
upon that which, being beneath them, also as it were 
gives way to them up to a certain point ; so that, 
even if the bending does not take place in any other 
part, it must at any rate do so at the point where the 
wing begins in flying insects ^ and in birds, and where 
the analogous part begins in other animals, such as 
fishes. In other animals, snakes for example, the 
beginning of their bending is in the joints of the body. 
In winged creatures the tail is used, like the rudder 
in a ship, to direct the flight ; and this too must bend 
at the point where it joins the body. Flying insects 
also, therefore, and those birds ^ whose tails are ill- 
adapted for the purpose just mentioned, peacocks, 
for example, and domestic fowls and, generally, those 
birds which are not adapted for flight, cannot keep 
a straight course. Of the flying insects not a single 
one possesses a tail, so that they are carried along 
like rudderless ships and collide with anything that 
they happen to meet. The same is true of sheath- 
winged insects,'' such as beetles and cockchafers, 
and the sheathless insects, such as bees and wasps. 
The tail is useless in such birds as are not adapted 
to flight, the porphyrio,*^ for example, and the heron 
and water-fowls in general ; these fly stretching out 

" Coleoptera. 

<* The identity of this bird is disputed. W. W. Merry (on 
Aristoph. Aves, 707) suggests some kind of coot ; D'A. W. 
Thompson (on H.A. 509 a 11, 595 a 13) suggests the purple 
coot or the flamingo. 



710a , V . , , , , . 

reivovra, Kai ;\;pa)VTat arr ovpoTtvyiov tols 

15 aKeXeai Trpog to KarcvOvveiv rrjv Trrrjcnv, j3pa- 
Seta 8* 17 TTTrJGis tujv oXoTTrepcov iorl koI dadevfjs 
Sto. TO jJiTj Kara Xoyov €X^t,v r-qv rcov Trrepcov cf)V(jLV 
TTpog TO rod Gcofiaros ^apos, aAAct to fikv ttoXv, 
TO, Se fjLLKpa Kal dadevrj. cjOTiep dv ovv el oA- 
KaSiKOP ttXoIov emx^ipoiri KcoTrais TroielaOai rov 

20 ttXovv, ovtoj ravra rfj TTTiqcjei XPV'^^^' '^^^ V 
dcrdeveia Se avrchv re rcov nrepajv Kal rj rrjs 
eKcjivcreajg avfi^aXXeral n Trpo? ro XexOev. tojv 
8' opvidojv to) piev racp ro ovpoTTvyiov ore [xev 
Sid ro pieyedos dxp'qcrrov, ore Se Sid ro ano- 
fidXXeiv ovdev (hcjyeXel. virevavriajs 8' exovoiv el 

25 opvides rots oXoirrepois rrjv rcjv Trrepojv (fyvoiv, 
pudXiCTra 8* ol rdx^'Orra avrcov veropuevoL. roiovroi 
8* ot yapn/ja)vvx^s' rovrois ydp rj raxvTrjs rrjs 
Trnqoecxis XPI^^I^^^ Trpds rov ^lov. dKoXovOa 8' 
avra)v eoiKev elvai /cat rd Xoirrd pLopia rov ao)- 
puaros TT/oos" rrjv olKeiav Kivqaiv, Kecf)aXr] pLev 

30 aTTavrajv puKpd /cat avx'^^ ov Trax^s, orrjdog 8' 
loxvpdv /cat d^v, o^v piev Trpos ro evrovov elvai, 
Kaddnep dv el ttXolov rrpcopa XepL^coSovs, loxvpov 
Se rrj 7Tepi(j)VGei rrjg oapKos, tv' drrojSelv Svvrjrai 
7iOb rov TTpoGTTLTTrovra depa, Kal rovro paSlcog Kal pLT] 
puerd TTOvov. rd 8' oinudev Kovcjya Kal ovvqKOvra 
ndXiv els orevoVy tr' eTraKoXovOfj rolg epLnpoadev, 
pLT] ovpovra rov depa hid rd rrXdros. 
5 XI. Kat TTepl piev rovrojv hicjpiodoj rov rpoirov 
rovrov, rd he pLeXXov ^cpov 6p66v jSa8teta^at 8toTt 
Slttovv re dvayKalov eoriv elvai, Kal rd fxev avoj 
rod (jcjpLaros p^^py] Kov(f)6repa e'xetP' rd 8' v^eorwra 
rovrois ^apvrepa, bfjXov pbovojs ydp dv ovrojs 


their feet in place of a tail and use their legs instead 
of a tail to direct their flight. The flight of flying 
insects is slow and weak, because the growth of their 
wings is not in proportion to the weight of their body ; 
for their weight is considerable, while their wings 
are small and weak ; so they use their power of flight 
like a merchant-ship attempting to travel by means 
of oars. The weakness also of the wings themselves 
and of their manner of growth contributes to some 
extent to the result which we have described. Among 
birds, the peacock's tail is at one season of no service 
because of its size, at another useless because the 
bird moults. But birds are the exact opposite of 
winged insects in the nature of their ^^ings, especially 
the swiftest flyers among them, namely, those with 
curved talons ; for their swiftness of flight is useful 
in enabling them to gain their livelihood. The other 
parts of their body, too, seem to be similarly adapted 
for their particular movement, the head being always 
small and the neck not thick and the breast strong and 
sharp — sharp so as to be compact like the prow of a 
light-built ship, and strong owing to the way the flesh 
grows — so as to thrust aside the air which meets it, 
and that easily and without effort ; but the hinder 
parts are light and contract again to a narrow point, 
in order that they may follow the forward parts with- 
out sweeping the air by their breadth. 

XL So much for the discussion of these topics. 
The reason why an animal which is to walk erect 
must both be a biped and also have the upper part 
of its body lighter and the parts situated beneath 
these heavier is obvious ; for only if it were so 



710b , ^, , V , , . , , s, S , 

exov OLOV T eirj cpepeiv eauro paoLOJs. oioirep 

10 dvdpCOTTOS fJLOVOV OpOoV TCOV t,Cx)a>V (X)V TO, OKeXrj 

Kara Xoyov e;\;e6 Trpos ra dva> rod ocofxaros pLeyLora 
rwv VTTOTToSojv Kal laxvporara. SrjXov Se iroieZ 
TOVTO Kal TO Gvp,^aXvov Tols TTaihioLS' ov yap 
hvvavrai ^ahit^eiv opSd Sta to rravra vavajht] ^Ivai 
Kal /xet^oj Kal laxvporepa ex^iv 7) Kara Xoyov^ rd 

15 dvoj pLeprj rod crdj/xaros' rcov Karojdev. Trpo'Covarjs 
8e ttJ? rjXiKLas av^7]GLV Xapi^dvei rd Kara) /xaAAov, 
jJL€Xpt' TTep dv Xd^coui ro TTpoarJKov pbiyedos, Kal 
TTOiovvrai rore rots GcopLaai ttjv ^dhiaiv opO-qv. 
ol S' opvides Kov(f)OL ovres StVoSes" elui hid ro 
OTTLaOev avrols ro ^dpos elvai, KaOdrrep ipydt^ovrai 

20 rovs L7T7T0VS rovs x^^f^ovs rovs rd rrpoadia fjpKoras 
rojv GKeXcov. alriov 8e /xaAtcrra rod StVoSa? 
dvras SvvacrOaL iurdvai ro ex^iv ro Icrx^ov opLOiou 
pirjpcp Kal nqXiKovrov ware SokeXv Svo pL7]povs 
€X^t,v, rov r iv rep GKcXei rrpo rrj? Kap,7Trjs Kal rov 
TTpos rovro ro pilpos (Xtto rrj? eSpag' eon 8' ov 
pLiqpos dXX IcrxLOV. €t ydp ptrj rrfXiKOvrov rjV, 

25 ovK dv rfv opvis hiTTovs. uxjTTep ydp rots dvdpcxj- 
TTOis Kal roig rerpdiTOGi t,a)ois, evOvs dv rjv drro 
^paxios dvros rod lux^-ov 6 pLrjpos Kal ro dXXo 
OKeXos' Xiav ovv -qv dv ro crco/xa Trdv nporreres 
avr(ji)v. vvv Se p,aKp6v ov piixP^ ^'^^ pLearjv Trapa- 
retVet rrjv yaorepa, war ivrevOev rd OKeXt) vtt- 

30 epr]p€L(Tp,€va cfyepei ro acofia Trdv. (jiavepov 8' 
cfc roTjrajv Kal on opdov ovk ivSex^Tai rov 
opviBa etvac wanep rov dvOpojirov. rj ydp rcov 
TTrepcov if)vais (hs exovai ro ucopia vvv ovrojs 
711 a avrols XPV^^H-^^ ianv, opdols 8* ovaiv dxp^cTTOs 
1 ^ Kara \6yov om. PY. 


constituted would it be able to carry itself easily. 
Therefore man, the only erect animal, has legs larger 
and stronger in proportion to the upper part of his 
body than any of the other animals which have legs. 
What happens with children illustrates this : they 
cannot walk erect because they are always dwarfish 
and have the upper parts of their body too big and 
too strong in proportion to the lower parts. As they 
grow older, the lower parts increase more quickly, 
until they attain their proper size ; and it is only then 
that they can walk ^vith their bodies erect. Birds 
are lightly built but can stand on two feet because 
their weight is at the back, just like bronze horses 
which are made by sculptors with their fore-legs 
raised in the air. The chief reason why birds can 
stand although they are bipeds is that their hip-joint 
resembles a thigh and is of such a size that they seem 
to have two thighs, one on the leg above the joint and 
the other between this and the fundament ; but it is 
not really a thigh but a hip. If it were not so large, 
a bird could not be a biped ; for then, just as in man 
and the quadrupeds, the thigh and the rest of the 
leg would be directly attached to a short hip, and so 
the whole body would tend to fall forward too much. 
But, as it is, the hip, being long, extends up to the 
middle of the belly, and so the legs form supports at 
that point and carry the whole body. It is clear too 
from this that it is impossible for a bird to stand erect 
in the way that a man stands ; for the way that birds* 
^vings grow is useful to them in the position in which 
they now hold themselves, but if they stood erect, 



av Tjv, coGTTep ypacpovGL rovs epcoras exovras 

"AjLta yap rot? elprjixevois hrjXov on ou8' dvdpcoTTOV 
ovS^ el d'AAo Tt TOiovTov eon Tr]v jjiopcf)rjv Svvarov 
eli^aL TrrepcoTov, ov jjlovov on TrXeioai o-qfieLOis Kivq- 

5 oerai 7) rerrapoLv evaipiov 6v, dAA' ort dxP'^'^'^os 
avTols T) T(x)v TTTepvycov e^Ls Kara (f)voiv klvov- 
fievoLS' 7) Se (f)voi? ovSev TTOieZ Trapd (f)VOLV. 

XII. "Ort fJLev ovv el fxr) Kapuijjis rjv ev rots 
GKeXeoLv 7) ev raZs co/xoTrAdrats" koI laxloi?, ovdev 
olov 7' Tjv av T(x)v evalfxajv Kal vttottoSojv rrpo- 

10 ^aiveiv, elp-qrai Trporepov, /cat on Kafjupis ovk dv 
rjv fjLTjOevos rjpejjiovvTos, on re evavriojs ol re 
dvdpcoTTOL SiTToSes ovres Kal ol opvides rrjv tcjv 
(jKeXdjv TTOLovvrat KafMipLv, en 8e rd rerpdiToha 
VTTevavTLcos Kal avrols Kal rots' dvOpajnoLg. ol 
fjiev yap dvOpojiroi rovg piev ^pa^i'Ovas KapnTTOVOiv 

15 cTTt TO. ACotAa, rd he OKeXrj eVt to Kvprov, rd 8e 
rerpaTToSa rd fiev TTpoodia OKeX-q inl to Kvprov, 
rd 8' oTTLGOta errl to koZXov opLoloJS 8e Kal ol 
opviBes. aiTiov 8* ort r] (f>vGis ovhev hiqpLiovpyel 
fjLaTrjv, a)G7Tep e'cprjTai rrporepov, dXXd iravTa rrpos 
TO ^eXTLGTOv eK Tcbv ivSexop^evwv . uior irrel 

20 ttoLglv ogols VTTapx^i Kard (J)vglv tj /caret tottov 
fxeTa^oXrj tolv GKeXotv, eGTwrog p.ev eKaoTOV to 
^dpos ev TovTcp eGTi, Kivovpievoi? 8' et? to Trpoodev 
Set roi^ 77d8a tov rjyov/jLevov ttj deoeu Kovcpov etvaL, 
Gvvexovs 8e ttjs rropeias yivopieviqs avdis ev tovto) 
TO pdpog aTToXapL^dveiv, SrjXov cos" dvayKalov eK 

25 TOV KeKdp.(f)dai to GKeXos avdis re evdv yiveodai, 
pLevovTos TOV re Kard tov npoojodevTa noSa 
Gr]p,€iov Kal TTJs KV-qpLTjs. TOVTO 8e GvpLpalveiv d/ia 


as winged ciipids are represented in pictures, the 
wings would serve no purpose. 

At the same time it is clear from what has been 
said that man, or any other creature of like form, 
cannot be winged, not only because, being red- 
blooded, he w^ould then move at more points than 
four, but also because the possession of wings would 
be useless to him when moving in a natural manner. 
Now nature creates nothing unnatural. 

XII. It has already been stated that, if there were 
no bending in the legs or shoulders and hips, none 
of the animals which are red-blooded and have feet 
could progress ; and that bending would be impos- 
sible if something were not at rest ; and that men 
and birds, being both bipeds, bend their legs in 
opposite directions ; and, furthermore, that quadru- 
peds bend their pairs of legs in opposite directions 
to one another and in an opposite manner to men. 
For men bend their arms concavely and their legs 
convexly, but quadrupeds bend their front legs con- 
vexly and their back legs concavely ; birds too do 
the latter. The reason is that nature never does 
anything without a purpose, as has been said before, 
but creates all things with a view to the best that 
circumstances allow. And so since in all creatures 
which possess by nature the power of locomotion by 
means of their two legs, when each leg is stationary 
the weight must be upon it, but when they move 
forward, the leading leg must have no weight upon 
it, and as progression continues it is necessary to 
transfer the weight on to this leg ; it is clearly essential 
that the leg after being bent should become straight 
again, the point at which the leg is thrust forward 
and the shin remaining at rest. And it is possible 



/cat TTpo'Cevai ro l^wov eis" rovixTrpoadeu fxev exovros 

TTjv KafJLTTrjV rod rjyouiievov (iKeXovg Svvarov, els 

Tovmodev 8' ahvvarov. ovro) jxev yap npoevexGev- 

so ros rod crco/xaTo? tj eKraais rod gkIXovs ecrrai, 

€K€LVCOs 8' dvevexOevTog. ert 8' et? ro omoOev 

[lev rrjs Kap,7T7Js ovorjs Sta Svo KLvqorecov eyiyver 

av 7) rod ttoSos Oeais vnevavriajv re avrais,^ Kal 

711 b rrjs fJLev els ro OTnaOev rrjs 8e els ro epLTrpoadev 

avayKOLOV yap ev rfj GvyKajJu/jei rod OKeXovs rod 

jjiev jxr^pod ro ecrxcurov els rovTnodev Trpodyeiv, 

rrjv 8e Kv^fxrjv oltto rrjs KafJLTrrjs els ro efiTrpoaOev 

Tov TToSa KLvetv. els ro epLTrpooOev 8e rrjs Kafxrrrjs 

5 ovarjs, ovd^ vrtevavriais Kivijorecn pna re rfj els 

TO efjLTrpoddev rj Xexdetaa TTopeia Gvpi^rjaerai. 

*0 [lev ovv dvdpcxJTTos hinovs cjv Kal rrjv Kara 
TOTTOV [jLera^oXrjv Kara (f)V(Jiv roXs GKeXeorL ttolov- 
fjLevos 8ta rr]v elprjjjievr^v alriav KajXTrrei els ro ejJL- 
rrpoodev rd GKeXr], rovs 8e ^paxlovas eirl ro kolXov 
10 evXoyoJS' dxp^jcrroi ydp du rjaav KaixTTropievoL rov- 
vavriov Trpos re rrjv rojv x^'^pd)^ XPV^^^ '^^^ Trpos 
TTjv rrjs rpo(f)'rjs XrjipLV. rd 8e rerpdnoSa Kal 
^cnoroKa rd jJLev ejJLTrpoodev GKeXr], eTTeiSr] rjyelrai 
re rrjs TTOpeias avr(x)v Kal eon radr ev rep puepeL 
TO) epLTTpoaOev rod acopiaros, dvdyKr] KdpuTTrecv 
15 cTTt rrjv 7Tepi(f)epeiav Sid rr]v avrrjv alriav rjvnep 
Kal ol dvdpojTTOi' Kard ydp rodro opLOLOJS exovcnv. 
SiOTTep Kal rd rerpdiroSa KdpLrrrovGLV els ro 
TTpoaQev TOV elprjpLevov rpoirov. Kal ydp ovrojs 
piev rrjs Kdpujjecos avrojv yivopievrjs eirl ttoXv 
SvvijGOvrai rovs rroSas pLerewpL^etv ivavrlcos 8e 

* virepafTLuv T€ avrals Jaeger: vwevapTicos re (5e UZ) aiiTai 


for this to happen and for the animal at the same 
time to progress if the leading leg can bend forward, 
but impossible if it bends backwards. For in the 
first case the extension of the leg will take place with 
the forward movement of the body, in the second 
case with its backward movement. Further, if the 
bending were backwards, the planting of the foot 
would be carried out by two movements contrary to 
one another, one backwards and the other forwards. 
For in bending the leg it is necessary to draw the 
extremity of the thigh backwards, and the sliin 
would move the foot forwards from the point of 
bending ; but if the bending be forward, the 
progression described above will take place not by 
two contrary movements but by a single forward 

Man then, being a biped and carrying out the 
change from place to place in a natural manner by 
means of his legs, bends his legs forwards for the 
reason already stated, but bends his arms concavely. 
This is only in accordance with reason ; for if they 
were bent in the opposite direction, they would be 
useless for the purpose of the hands and for taking 
food. But viviparous quadrupeds of necessity bend 
their front legs in an outward curve, because these 
legs lead the way Avhen they walk, and are also 
situated in the front part of their bodies ; and the 
reason is the same as in man, for in this they resemble 
man. Thus the quadrupeds too bend their legs 
forward in the manner already described ; for indeed, 
since they bend their legs in this way, they will be 
able to raise their feet high in the air, whereas, if 
they bent them in the opposite direction, they -would 



20 KaiJLTTTOVTCs fJLLKpov aiTO T7y? yTj? av avTOVS efie- 
T€<x>pil,ov Sta TO Tov T€ fiT^pov oXov Kal Trjv 
KafJLTT-^i', a^' rjs r) Kv-qixiq 7Te(f)VKev, vtto rfj yaarpl 
yiyveoQ ai Trpoiovros aurov. twv 8* oTnadev (jkeXcov 
el jxev rjv els to efXTrpocrdev r) Kapn/jL?, rcov Trohcov 
6 fieTecopLGpLOs ofioicos O.V avTols et)(e rols Trpo- 

25 aOiOLs {enl Ppo-X^ 7^9 ^^ eyiyvero /cat rovrois 
Kara rrjv dpaiv rcov crKeXcbv, tov re ixrjpov /cat 
rrjs KajJLTTTJg djX(f)OT€pcov vtto top rrjs yaarpos tottov 
VTroTmrrovTOjv) , el S' els to oTTiadev, Kaddirep /cat 
vvv KdfjLTTTOVGLv, ovOev ipLTTohiov avTols yiyverai 
TTpos TTjv TTopeiav iv rfj roLavrrj KLVijaeL rcov ttoSwv, 
en rots ye dr]Xal,ofievoLS avrcov /cat vpos rrjv 

80 roLavrrjv Xeirovpyiav dvayKoiov rj ^eXriov y ovtoj 
K€Kdii(f)6aL rd OKeXrj- ov yap pdStov rrjV Kdfjujjiv 
TTOiovjjLevojv evros vcf)^ avrd e;(etv Ta reKva koX 
GKeTrdt^eLv . 
712 a XIII. "Ovrcov he rerrdpcov rpOTTCJV rrjs Kdfu/jeajs 
Kara rovs ovvhvaujxovs^ (dvdyKiq yap KdpLTrreiv 
rj eVt ro koZXov /cat Ta TTpoodta /cat rd OTrlaOLa, 
Kaddrrep ecf) ^ots A, rj evl rovvavriov em ro Kvprov, 
KaddrTep e<^' ols B, r) avrecrrpapLfxevajs /cat jir] errl 
5 rd avrd, dXXd rd jxev rrpoadia eirl ro Kvprov, rd 
8' OTTLodia eVt ro koZXov, Kaddnep €(f)* ols ro F, 
■^ rovvavriov rovrois rd jxev Kvprd npos aAAr^Aa, 

* avudvacrfiovs Z : (Twd^afxovs ceteri. 


lift them only a little way from the ground, because 
the whole of the thigh and the joint from which the 
shin grows would come up against the belly as the 
animal advanced. On the other hand, if the bend- 
ing of the back legs were forward, the raising of the 
feet would be similar to that of the front feet (for 
they could only be raised a short distance by lifting 
the legs, since the thigh and the joint of both legs 
would come up under the region of the belly), but 
the bending being, as it is, backwards, there is no- 
thing to hinder their progression as they move the 
feet in this manner. Again, for those animals which 
are suckling their young, it is necessary, or at any 
rate better, that their legs should bend in this way 
with a view to this function ; for if they bent their 
legs inwards, it would not be easy for them to keep 
their young underneath them and to protect them. 

XIII. Now there are four ways of bending the legs 
taking them in pairs. Both the fore and the hind 
legs must bend either concavely, as in figure A ; or 
in the opposite manner, that is convexly, as in B : 

(Mich, supplies the figures which are lacking in the mss. In each group 
the front legs are the left pair, the hind legs the right.) 

or inversely, that is to say, not in the same direction, 
but the forelegs bend convexly and the back legs 
concavely, as in C ; or (the converse of C) with the 
convexities towards one another and the concavities 



ra Se KolXa Iktos, KaOdirep ex^t e(/>' oh to A), 
CO? [jiev €X^L e^' olg to A t) to B, ovdev Kdinrrer ai 
ovre Tix)v hmohojv ovre rcov reTpaTToScov, (Ls Se 

10 TO r, rd TCTpaTToSa, cos Se to A, rcov fxev rerpa- 
TToScov ovOev TrXrjv iXecfias, 6 8' dvOpcoTTOS rovs ^pa- 
X^ovas Kal rd GKeX-q- rovs fi^v ydp cttl to kolXov 
KdfjLTrrei, rd Se (iKeXr) Ittl rd Kvprov. 

'Aet 8' ivaXXd^ Ivavriojs ^X^'' ''"^ KcoXa rds 
KdfJLijjeLs rols dvOpcoTTOLS, OLOV rd wXeKpavov eirl rd 

15 KolXov, 6 he Kaprrds rrjs x^^P^S ^ttI rd Kvprov, Kal 
irdXiv 6 ajfios eVt to Kvprov ojoavrcos 8e Kal irrl 
rcov o-KeXcdv d p,rjpog eVt to koTXov, rd 8e ydvv irrl 
rd Kvprdv, d 8e ttovs rovvavriov inl rd koiXov. Kal 
rd Kara) Brj rrpds rd dvco (f)avepdv on ivavriojs' 
T) ydp dpx^] VTrevavricos, d fiev cofjios inl rd Kvprov, 

20 o 8e fxrjpds inl rd kolXov Sid Kal d fxev ttovs 
irrl rd kolXov, d Se Kapirds rrjg ^etpos" eVt rd 

XIV. At piev ovv Kafju/jeis rcov gkcXcov rovrdv 
re rdv rpdrrov exovui Kal 8td rd? air Las rds 
elp-qpiivas , KLvetrai he rd OTTLadia rrpds rd e/x- 

25 rrpoodev Kard hidpLerpov pierd ydp rd he^idv rcov 
epurpoudev rd dpiorepdv rcov oTTiudev klvovglv, 
elra rd dpiorepdv rcov epLTrpoadev, pierd he rovro rd 
he^idv rcov oTTiGdev. airiov 8' OTt el piev rd 
epLTTpoaOev dpua Kal npcoroVy hteGTrdro dv tj Kal 
TrpoTTerrjs dv eyivero tj ^dhiGLS otov e(f)eXKopevoLS 

30 TOts" OTTLadev. en 8' ov TTopeia dXXd dXuis rd 
rocovrov ;\;aA€7rov he avvex"^ TToieladaL rrjv /xeTa- 
^oXrjv dXXofxeva. a-qpelov he' rax^ ydp aTrayopev- 
ovoL Kal vvv rcov lttttcov ogol rdv rpdnov rovrov 
rroiovvrai rr)v KLvr]GLv, otov ol rropiTTevovres. X'^P^^ 


outwards, as in D. No biped or quadruped bends its 
limbs as in figure A or B, but quadrupeds bend them 
as in C. The bendings illustrated by figure D occur 
in none of the quadrupeds except the elephant, and 
in the movement of the arms and legs by man, for 
he bends his arms concavely and his legs convexly. 

In man the bendings of the limbs always take 
place alternately in opposite directions ; for example, 
the elbow bends concavely but the wrist convexly, 
and the shoulder again convexly. Similarly in the 
legs, the thigh bends concavely, the knee convexly, 
and the foot, on the other hand, concavely. And 
obviously the lower limbs bend in opposite directions 
to the upper ; for the origin of movement bends in 
opposite directions, the shoulder convexly and the 
thigh concavely ; therefore also the foot bends con- 
cavely and the \\Tist convexly. 

XIV. The bendings, then, of the legs take place 
in this manner and for the reasons stated. But the 
back legs move diagonally in relation to the front 
legs ; for after the right fore leg animals move the 
left hind leg, then the left fore leg, and after it the 
right hind leg. The reason is that, if they moved the 
fore legs at the same time and first, their progression 
would be interrupted or they would even stumble 
forward, with their hind legs as it were trailing behind. 
Further, such movement would not be walking but 
jumping ; and it is difficult to keep up a continuous 
movement from place to place by jumping. An illus- 
tration of this is that, in actual fact, horses that move 
in this manner,^ for example in religious processions, 
soon become tired. For this reason, then, animals do 

" i.e. prancing instead of walking. 



712 a ^ ^ ^ ,, 

fX€V ovv rots kfXTTpoGOev /cat oTTioOev Sta ravra 

712 bou^ TTOiovvrai rrjv Kivrjcnv' el Be rot? Scftot? a/x- 
^orepoLs npcoTOLg, e^co dv eyiyvovro rcov ipei- 
afidrcDV Koi eTmrrov dv. el Srj avdyK-q fxev 7) 
TOVTOJV Tctjv rporrojv OTTorepovovv TTOielaBaL ttjv 
Kivqaiv Tj Kara SidfxeTpov, {jltj evSexerai 8' eKeivoiV 
6 pi-qherepov, dvayKr) Kivelodai Kara Scdpierpov 
ovroj yap Kivovfieva axurep elp-qrai ovSerepa rovrcov 
olov re 7racr)(eLV. /cat Sta rovro ol lttttol /cat oo"a 
roiavra, lararat 7Tpo^e^7]K6ra Kara SidpLerpov, 
/cat ov rots Se^toXs 'r) rolg dpiurepoZs dpL^orepois 
a/xa. rov avrov he rpoTTOv /cat ocra TrXeiovs '^X^^ 
10 TToSa? rerrdpojv TTOtetrat rrjv klvt^glv del yap ev 
rots rerrapcri roZs ecfie^rjs rd oTriadia Trpos rd 
efjLTTpocrOev Kivelrai Kara hidpierpov. hriXov 8' 

CTTt TOtS" ^paSeOJS KLVOVpieVOLS. Kal ol KapKivoi 

yap rov avrov rporrov Kivovvrai' rcov ttoXvttoScov 
yap etCTtv. del yap /cat ovrot Kara Siafxerpov 

15 Kivovvraiy e<^' orrep dv TTOLcovrau rr)V rropeiav. 
Ihiojs yap rovro rd l^cpov rroieZrai rrjv KLvrjaLV 
jjLovov ydp ov KLvelraL errl rd Trpoadev rcbv t,a)a}v, 
dAA* eirl rd rrXdyLOV. dXX ejrel roZs o/x/xacrt 
Stajptcrrat to TrpoaOiov, rj (j)VGi£ Tre7TOL7]Kev dKO- 
XovdeZv Svvafievovs rov? 6(f)daXf.iovs roZs kcoXols' 

20 Kivovvrai ydp els rd TrXdyiov avroZs, ware rpoirov 
rivd /cat rovs KapKivovs KiveZadai Sta rovr* enl 
rd epLTTpoaOev. 

XV. Ot 8' dpvides rd orKeXrj KaOdrrep rd rerpd- 
TToba KdfJLTTrovaLV. rporrov ydp riva TTapaTrX-qaiajs 

1 0.5 P : om. SYUZ. 


not move separately with their front and back legs'*; 
and, if they moved with both their right legs first, 
they would not be above their supporting hmbs and 
would fall. If, then, they must necessarily move in 
one or other of these two ways or else diagonally, 
and neither of the first two ways is possible, they 
must necessarily move diagonally ; for if they move 
thus they cannot, as has been explained, suffer 
either of the above ill results. For this reason horses 
and similar animals stand at rest with their legs 
advanced diagonally and not ^^-ith both right or both 
left legs advanced at the same time. And those 
animals which have more than four legs move in 
the same manner ; for in any four adjoining legs the 
back legs move diagonally with the fore legs, as can 
be plainly seen in those which move slowly. 

Crabs too move in the same fashion, for they are 
among the polypods. They, too, always move on 
the diagonal principle in whatever direction they are 
proceeding. For this animal moves in a pecuUar 
manner, being the only animal to move obliquely 
and not forward. But since " forward " is determined 
in relation to the vision, nature has made the crab's 
eyes able to conform with its limbs ; for its eyes 
move obliquely, and so, for this reason, crabs too can, 
in a sense, be said to move ** forward." 

XV. Birds bend their legs in the same manner as 
quadrupeds ; for in a way their nature is closely 

" i.e. do not move first the front legs together and then 
their back legs together. The ms. authority is strongly in 
favour of the omission of the negative: but 712 b 4 " one or 
other of these two ways " implies the alternative of movement 
with the front legs together and then the back legs together, 
or else with the right legs together and then the left legs 



712b , . „ . ^ V , , 

T) (pvais avTCjov e;^ef rot? yap opvLOiv at Trrepvyes 
avrl rojv TrpoaOiajv OKeXwv eloiv. hio /cat K€Kap,- 

25 /xeVat TOi^ auToi^ etcrt rporrov uiOTiep e/cetVot? to, 
TTpoaOca GKeXr], inel ttjs eV tt^ Tropela KLVi^aeajg 
rovTOis OLTTO rchv Trrepvyojv rj Kara ^vacv apxTj 
rrjs fJierapoXrjg eGriv TrrrJGLS yap €Gtlv tj tovtcdv 
OLKEia KLVYjGLs. StoTTcp a^aipe6ei(j(x)v Tovrcov ovd^ 

30 eGrdvai ovre Trpo'Civai h-uvair* av ovdels opvis. 

"Ert SlttoSos ovto? /cat ovk opdov, /cat ra €/x- 
TTpooOev pieprj rod acofiaros Kovcfiorepa exovrog, 7} 
dvayKalov 7) ^iXnov Trpos ro iordvai h-uvaaOai rov 
jJLTjpov ovTOJS vrroKeijJLevov e;\;ety cos" vvv e;!^et, Xlyoj 
8' ort etV TO oTTLadev TrecjiVKora. dXXd (jltjv el eSct 
TOVTOV ex^i-v rov rponov, dvdyKT] rrjv Kdpufjiv irrl 
713 a ro KoiXov yiveodai rod OKeXovs, KaOdrrep roZs 
rerpdiTOGiv eTrl rcov OTTiaOiojVy hid rr)v avrrjv alriav 
rjVTTep etrrofjiev IttI rwv rerpairoSajv /cat ^cooro/ccov. 
"OAoJS" Se OL re opnOes /cat ra oXoirrepa raJv rre- 
rofievajv /cat ra ev rw vypco yeucrrt/ca, doa avrcov 
5 8t* opydvojv rrjv eVt rod vypov TTOielrai rropeiaVy ov 
XaXeTTOV Ihelv on ^eXnov e/c TrXaylov rrjv rcov el- 
prjfjievojv jjiepdjv 7Tp6a(j)VGiv ex^cv, Kaddnep /cat 
(j)aLverai vvv vrrdpx^iv avrols erri re rcov opvidcov 
/cat rdov oXoTrrepwv. ravrd Se rovro /cat eTrl rcov 
IxOvcov roLS ixev yap opvioiv at irrepvyes, rots S' 

10 ivvSpoLS ra Trrepvyia, ra he TrrlXa rots oXonrepOLS 
e/c rod TrXayiov rrpoGTrecfiVKev. ovrco ydp dv rd- 
Xi'Crra /cat laxvporara hiaareXXovra rd puev rov 
depa rd he ro vypov iroiolro rrjv KLurjaLV els ydp 
ro efJLTTpoodev /cat rd oTnadev fiopia^ rod Gco/xaros 
erraKoXovOoiiq dv vireiKovri cf)ep6fieva ra fxev ev 

i& ro) vypo) rd h* ev ro) depi. ra Se rpcoyXohvriKd 


similar. For in birds the wings serve instead of front 
legs, and so they are bent in the same manner as the 
front legs of quadrupeds, since in the movement 
involved in progression the natural beginning of 
the change is from the wings, for their particular 
form of movement is flight. Hence, if the wings 
were taken away, no bird could stand or progress 

Further, since the bird is a biped and not erect, and 
the front parts of its body are lighter, it is either 
necessary (or at any rate more desirable), in order to 
enable it to stand, that the thigh should be placed, as 
it actually is, underneath, by which I mean growing 
towards the hinder part. But if the thigh is neces- 
sarily in this position, the bending of the leg must be 
in a concave direction, as in the back legs of quad- 
rupeds, and for the same reason as we gave in dealing 
wdth viviparous quadrupeds. 

Generally in birds and winged insects and creatures 
that s^^'im in the water (all, that is to say, that progress 
in the water by means of their instrumental parts), it 
is not difficult to see that it is better that the attach- 
ment of such parts should be oblique, as in fact 
it seems actually to be in the birds and the flying 
insects. The same is also true of the fishes ; for the 
wings in birds, the fins in fishes, and the wings in 
flying insects all grow obliquely. This enables them 
to cleave the air or water with the greatest speed 
and force, and so effect their movement ; for the 
hinder parts, too, can thus follow in a forward direc- 
tion, being carried along in the yielding water or air. 

The oviparous quadrupeds which live in holes, 

* Kal TO. d-madev fj.6pia Jaeger : Kal rb oirLo-d^u to. (rd om. YZ) 
fidpia libri. 




koSclXol /cat aavpoL Kal do-zcaAa^tDrat /cat cfivSes 
T€ /cat ;(eAa)vat, Trdvra e/c rou TrXayiov TTpooire- 
<f)VK6ra TO, GKeXi) e;\;et /cat cTrt tt} yfj /cararera/xeVa, 

20 /cat /cd/x77Tet ets" to 77-Adytov, Std to ovtoj ;^/3')]CTtju,a 
eti/at TT-pos" TT^i^ rrfs V7toSvg€co£ paarcovrjv /cat Trpos" 
TTjv CTTt TOts" ojot? i(j)ehpeiav /cat (JivXaK-qv. e^oj 
S* ovTcov avrujv, dvayKOiov rovs fjirjpous rrpoa- 
areXXovra^ /cat vttot tOe/xeva v<f>^ avrd rov jxereoj- 
piGjiov rod oXov uixifxaros TTOtetaOaL. tovtov 8e 

25 yivojjLevov /cd/xTiTetv auTO, ovx olov re aAAcus" t] 

XVI. To, 8* dVat/xa tcop' UTroTrdSaji^ OTt fxev 
TToXvTToSd ion /cat ovOev avrcov rerpaTTovv, 
TTpoTepov rjfjuv eLprjrai' StoTt 8' auTcDv dvayKoiov 
rjv rd GKeXrj ttXtjv raJv ioy^drcxjv e/c re rod TrXayiov 

7rpOG7T€(f)VK€VaL /Cat €1? TO dvCxJ TCI? KaflTTa? ^X^^^i 

30 /cat auTO, viro^XatGa elvai els to onLGdev, (jyavepov. 
aTTdvTOJV yap raJv roiovraiv dvayKaZov eo-Tt Ta 
fjL€Ga Tcov GKeXojv /cat YjyovjJLeva etvat /cat eVd/xera. 
el ovv vtt" avTols rjv, eSet auTO, /cat els to e/x- 
713 b TrpoGOev /cat ets" to oiriGdev ttjv Ka/JLTrrjv ^x^i'V, Std 
/xei^ TO riyelGdai els to efinpoGdev, 8td 8c to 
d/coAou^eti^ ets" to omGdev. eirel 8* dfK^OTepa 
GVfjL^alveLv dvayKalov avrols, Std tovto ^e^XaiGa)- 
5 Tat T€ /cat et's" to TrXdycov e;^et Td? KapLTrds, ttXt^v 
tcov eGxdTOJV TavTa 8' wGTrep irecfiVKe pdXXov, 
Ta piev (hs eTTOpLeva Td 8' ojs riyovpLeva. eTi Se 
KeKapiTTai tov Tpoirov tovtov /cat 8td to ttXtjOos 
TCOV GKeXcov rJTTov yap dv ovtcos €v ttj TTopela 
ipTTohid Te avTa avTols eirj /cat TrpoGKOTTTOi. tJ 

10 Te ^XacGOTTjs avTcov eGTi 8td to Ty3a)yAo8uTt/cd 


such as the crocodile, the common and the spotted 
hzard, and land and water tortoises, all have their 
legs attached obliquely and stretched out upon the 
ground ; and they bend them obliquely, since they 
are thus useful in enabling them to crawl easily into 
their holes and to sit upon and protect their eggs. 
Since their legs project, they are obliged to raise 
their whole body by drawing in their thighs and 
placing them underneath them ; and in this process 
they cannot bend them otherwise than outwards. 

XVI. It has already been said that bloodless 
animals which have legs are polypods, and none of 
them quadrupeds. Their legs, except the two 
extreme pairs, are necessarily attached obliquely 
and bend upwards and are themselves bowed some- 
what backwards ; and the reason for this is plain. 
For in all such animals the middle legs must both 
lead and follow. If, therefore, they were under- 
neath them, they would have to bend both for- 
wards and backwards — forwards because they lead, 
and backwards because they follow. But since they 
must do both these things, their legs are bowed 
and make their bends obliquely, except the extreme 
pairs, which are more in accordance with nature, 
since the first pair leads and the last pair follows. 
The number of legs is a further reason for their being 
bent in this way ; for they would thus be less likely 
to get in each other's way during movement and 
collide with one another. The reason that these 
animals are bow-legged is that they all, or most of 

1 TrpocrcrreWoi/ra (cum Mich.) Jaeger: 7rpocrrA\oj/ra libri. 



efvat TTOLvra t) tol TrXelara' ov yap olov re vi/irjXa 
elvai TO. I^ojvra^ rov rpoirov tovtov, 

01 8e KapKivoi TCxiv ttoXvttoScov TTepiTTorara 7r€(f)v- 
KauLV ovT€ yap eis" to TrpoaOev noLovprai ttjv rropelav 
TrXrjV oiCJTTep etprfraL Trporepov, ttoXXovs re rovg 
rjyovixevovs cxovgl (jlovol tujv t^cnoiv. tovtov 8* 

15 aLTiov Tj (TKXrjpoTTjg rwv TroSojv, Kal on ;\;pcDvTat 
ov vevaews X^P^^ avroZs dAAa iropeias' 7Tet,evovTa 
yap SiareXovatv. TTavrcjv fxev ovv tG)V ttoXuttoScov 
els TO TrXdyiov at KapLTrai, woTrep Kal tojv rerpa- 
TToScuv oaa rpcoyXohvriKd' TOiavTa 8' eWtv olov 
oavpai Kal KpoKoheiXoi Kal tol ttoXXol tcov cLo- 

20 TOKovvTOJV. auTLOv S' OTL TpojyXohvTeZ rd jxev 

TOL9 TOKOLS, Ta he Kal TO) ^LOJ TTaVTl. 

XVII. 'AAAa Tcbv fjiev dXXojv ^XaiaovTai ra KcoXa 
hid TO fiaXaKd etvai, tcov he Kapd^ojv ovtojv gkXtj- 
poheppLOJV ol TToSe? elolv IttI rw veZv Kal ov tov 
^ahit^eiv p^aptv Tchv he KapKivojv rj /ca/xi/ft? el? to 

25 TrXdyiov, Kal ov ^e/SAatcrcorat coGrrep rols cootokols 
Tcjv TeTpaiTohcov Kal toIs avat/xots" Kal TToXviroaiy 
hid TO GKXrjpohepjjia elvai ra KCjXa Kal ouTpaKcnhrj 
ovTL ov vevoTLKO) Kal TpajyXohvTTj- TT/Jos" TTJ yfj ydp 
6 ^Los. Kal GTpoyyvXos he ttjv p^op^riv, Kal ovk 
e;\;cov ovporrvyiov ojGTrep 6 Kdpa^os' Trpos ttjv 

80 vevGLV ydp ToZg Kapd^ois xprjcjtyLtov, o 8' ov vev- 
GTLKos. Kal dpLOLOv he to) OTnodev to TrXdyiov 
ex^i' piovosy hid TO rroXXovg ex^iv tovs rjyeixovas 
^ TO. ^u}i>Ta om. SU. 

« 712 b 20 f. 

*> Viz. two pairs of front legs. 

i.e. they walk both on dry land and in the sea. 

** The whole of the section is obscure, and the text doubtful. 



them, live in holes ; for creatures that live thus 
cannot be tall. 

Crabs are the most strangely constituted of all the 
polypods ; for they do not progress forward (except 
in the sense already mentioned ^), and they alone 
among animals have several leading legs.^ The 
reason is the hardness of their feet and the fact that 
they use them not for swimming but for walking ; 
for they always go along the ground.*' All the 
polypods bend their legs obliquely like the quad- 
rupeds that live in holes ; lizards, for instance, and 
crocodiles and most oviparous quadrupeds are of 
this nature. The reason is that they live in holes, 
some only during the breeding season, others through- 
out their lives. 

XVII. Now the other polypods ^ are bow-legged 
because they are soft-skinned, but the legs of the 
spiny lobster,^ which is hard-skinned, are used for 
swimming and not for walking.-'' The bendings of 
crabs' legs are oblique but their legs are not bowed, 
as are those of viviparous quadrupeds and bloodless 
polypods, because their legs are hard-skinned and 
testaceous, the crab not being a swimming animal 
and li\ang in holes, for it lives on the ground. More- 
over, the crab is round in shape and does not possess 
a tail like the spiny lobster ; for the latter's tail is 
useful for s^^'imming, but the crab does not swim. 
And it is the only animal in which the side is like a 
hinder part, because its leading feet are numerous.^ 

* There is no single word in English for this animal, the 
Latin locusta and the French langouste. 

' And therefore are not bowed, as Mich, explains. 

" Since the crab moves sidewise, one of its sides becomes 
as it were the back, but why it should be so for the reason 
given is obscure. 



713 b , c., . « , , , , 

TTooas. rovTov o airiov on ov KafjLTrrei €ls to 

714 a TTpoadev ovSe ^e^Aatcrcorat. rod 8e fxr] jSe^Aat- 

aaxjOai to airiov irpoTepov etpT^rat, -q GKXrjpoTrjs 
KOL TO ouTpaKcoSes Tov hepixaTos. avdyKrj hr] 
Std raura irdGL re Trpo-qyelad ai Koi ets" ro TrXdyiov, 
els fiev TO TrXdyLOV otl els to TrXdyiov rj Kdjiipts, 
6 TTCtcrt 8' OTi iv€7r6SL'C,ov dv ol rjpejJLOvvTes TToSes 
Tols KLVovjJLevoLS. ol 8e i/j-qTToeihels rwv IxOvojv, 
wcrrrep ol iTepocjiOaXpioi ^ahil,ovGLv, ovtco veovoiv 
SUcTTpaTTTaL yap avTcov rj ^vgis. ol 8e GT€yav6- 
TToSes Tcjv SpvWojv veovGL TOtg rroGLV, /cat Sia fxev 
10 TO TOV depa Se;^ea^at /cat dvaTTvelv hiTrohis €lgl, 
8ta 8e TO iv vypco tov ^lov ex^LV GTeyavonoSes' 
dvTL TTTepvyicov yap ;j^/07^crt/xot ol noSeg avTolg 


ol dXXoi /caret fxeGov, dAA' oiTLGdev pidXXov ^pa- 
XVGKeXojv yap avTwv ovtcov OTriGdev ovTa rrpos 
TTjV vevGLV ;!^p7^o-t/xa. ^paxvGKeXelg 8' clglv ol 


d(f)€XovGav TTjv (f)VGLv TTpooOelvaL et? Tovs TToSas, 
Kal dvTi TOV fJLTjKovs Trd^os dnoSovvaL tols GKeXeGi 
/cat TT-Adros" rots' ttoglv ;)(/3i^o-t/xot yap TrXaTels^ 

6vT€S jJidXXoV Tj /Xa/Cpot TTpOS TO d7TO^Ldl,€G6aL TO 

vypov, OTav vccoglv. 
20 XVIII. ^vXoycos 8e /cat Ta fiev TTTrjvd TToSas 
€;^et, ot 8' IxOves dVoSes" rot? fJLev yap 6 ^los iv 
ra> ^-qpo), fieTecDpov 8' det fxeveiv dSvvaTov, wgt 
dvdyKTj TToSas ex^Lv tols 8' lxQvglv iv ro) vypcb 
6 ^LoSy Kal TO vhojp SexovTaL, ov tov dipa. Ta 
Tl4b jJLev ovv TTTcpvyLa XPV^^H'^ Trpos to velvy ol 8e 
77086? dxpr]GTOL. et 8' d/x</)a) etxov, dvaL/xoL dv 
rJGav. ofiOLOJS 8' exovGLV ol opvcdes Tpoirov TLva 


The reason is that it does not bend its legs forwards 
and is not bow-legged. Why it is not bow-legged 
has been already explained before, namely, because 
its skin is hard and testaceous. For this reason it 
must lead off with all its legs and obliquely — obliquely 
because its bendings are oblique, and with all its legs, 
because otherwise those which were at rest would 
impede those which were moving. 

Flat-fish swim as one-eyed men walk ; for their 
nature is distorted. Web-footed birds swim with 
their feet. They are bipeds, because they take in 
l)reath and respire ; they are web-footed, because 
they live in the water, for their feet being of this 
kind are of service to them in place of fins. They do 
not have their legs, as the other birds do, in the 
centre of the body, but placed rather towards the 
back : for since they are short-legged, their legs 
being set back are useful for shimming. This class 
of bird is short-legged because nature has taken 
away from the length of their legs and added to their 
feet, and has given thickness instead of length to 
the legs and breadth to the feet ; for, being broad, 
they are more useful than if they were long, in order 
to force away the water when they are swimming. 

X^TII. It is for a good reason, too, that winged 
anim.als have feet, while fishes have none. The 
foiiner live on dry land and cannot always remain up 
in the air, and so necessarily have feet ; but fishes 
live in the water, and take in water and not air. 
Their fins, then, are useful for swimming, whereas 
feet would be useless. Also, if they had both feet 
and fins, they would be bloodless. Birds in a way 

^ TrXarers Z: Traxe's PSUY. 

s 539 


714b . , ^, . V ^ V V r , , 

TOLS LXOVGLV. Tot? /xei^ yap opvioiv avco at Trrepvyes 
5 eloi, Tols he TTrepvyLa Svo iv raJ Trpavel' koi rot? 
/xev iv ToTg vTrrioi^ ol iroheSy rols Se eV re tols 
VTTTLOLs Koi iyyus T(jL)v rrpavcov Trrepvyia tols 
ttXelgtols' kol ol i-iev ovpoiTvyiov exovGLv, ol S 

XIX. Hepl Se TOJV oGTpaKohepixcDV airop-qGeLev 

aV TLS TLS r] KLVTjGLS, Kal el {JLTj exovGL Se^LOV Kal 

apiGTepov, TTodev KLvovvTai' (fjalvovTat 8e klvov- 
io/x€va. 7) a)G7T€p dvoLTTrjpov Set rt^eVat ndv to 
TOLovTov yevos, Kal /ctveta^at ojjlolcos olov et rt? 
aTTOKoijjeie tcov vnoTroSajv tol GKeX-q, {tJX coGTrep 
7] (f)coK-q Kal rj vvKTepis' Kal yap raura TeTpaTToSa, 
KaKcos 8' eVrtV. to, 8' OGTpaKoSepfia Actvetrat /xeV, 
KLveLTaL 8e Trapa (fiVGLV ov yap eart KLvrjTLKa, dAA' 

15 CO? /Xey flOVLpLa Kal TTpOG7T€(f)VK6Ta KLUrjTLKa, CO? Se 

TTopevTLKa jJLovLjia. exovGL 8e (f)avXcx}s Kal ol KapKLvoi 
TO. Se^La, i-TTel exovGL ye. StjXol 8' 77 X^^'^T /^^t'^<^'^ 
yap /cat LGXVpoTepa rj Sefta, a>? BovXopJvcov St- 
ojpLGOaL Tcov he^LOjv Kal tojv apLGTepojv. 
20 To, jLtep' ouv Trept Tchv pLopiajv, tcov t' a'AAcov Acat 
raJv Trepl tt^v TTopeiav tcjv l,a)OJV Kal Trepl naGav 
rrjv /caret tottov [xeTa^oXrjv, tovtov e^ct tov TpoTTov 
TOVTWV Se SLCjopLGjj^evojv exofjLevov Igtl OecoprjoaL 

TTepl ipvxrjs. 

^ 7/ addidi. 

• i.e. a second pair of fins. 

* See I J. A. 527 b 35 If., where land-snails, sea-snails, oysters 
and sea-urchins are given as examples. 

« See ILA. 498 a 31, P. A. 697 b 1 flf. 

^ These Mords can only refer to the De anitna, which from 
its citation in the I)e generatione animalivm, De parflbiis 
animalium, etc., must be regarded as an earlier work. This 



resemble fishes. For birds have their wings in the 
upper part of their bodies, fishes have two fins in 
their fore-part ; birds have feet on their under-part, 
most fishes have fins ** in their under-part and near 
their front fins ; also, birds have a tail, fishes a tail-fin. 

XIX. A question may be raised as to what is the 
movement of testaceans,^ and where their movement 
begins if they have no right and left ; for they 
obviously do move. Must all this class be regarded 
as maimed and as moving in the same way as an 
animal with feet if one were to cut off its legs, or as 
analogous to the seal and bat, which are quadrupeds 
but malformed ? '^ Now the testaceans move, but 
move in a way contrary to nature. They are not 
really mobile ; but if you regard them as sedentary 
and attached by growth, you find that they are 
capable of movement ; if you regard them as pro- 
gressing, you find that they are sedentary. 

Crabs show only a feeble differentiation of right 
and left, but they do show it. It can be seen in the 
claw ; for the right claw is bigger and stronger, as 
though the left and right wished to be differentiated. 

So much for our discussion of the parts of animals 
and particularly those which have to do with progres- 
sion and all change from place to place. Now that 
these points have been settled, our next task is to 
consider soul.** 

has led some critics {e.g. Brandis) to reject the whole of this 
paragraph as a later addition. Such a paragraph, however, 
is a characteristic conclusion in Aristotle, and should not be 
rejected as a whole. It is quite possible that the words 
77-ept 4'^xi^ ^re corrupt, and indeed the word i/rfx^^ h^s been 
supplied by a later hand in Z, whereas the first hand had 
left a blank and had written loj-qa {sic) in tlie margin, which 
would be a reference to the latter part of the group of treatises 
known as the Parva Naturalia. 

.S2 541 


The Index is to be regarded as supplementary to the Sum- 
mary on pages 12-18. Further references will sometimes be 
found in the notes on Terminology, pages 24-39. 

The numbers 3 to 50 refer to the pages of the Introduction. 
The numbers 39a to 97b (standing for 639a to 697b) refer 
to the pages and columns of the Berlin edition which are 
printed at the top of each page of the Greek text. The lines 
are referred to in units of five lines ; thus 
40a 1= 640a l-640a4 
40b5 = 640b5-640b9. 
Such references include footnotes to the translation, 
f, ff = following section or sections. 
Under any heading, each entry is separated from the pre- 
ceding by a dash ( / ), unless it has the same page number. 

abdomen (abdominal cavi- 
ties) 50al0 

abomasum 74bl5 / 76alO 

abscess 67b5 

" abscession " 39 / 90a5 

Acalephae 81a35 

Aesop 63a35 

allantois 93b25 

Amia 76b20 

analogy, difference by 44b 10 
/ 45b5 

Anaxagoras 40b5 / 45a35 / 
77a5 / 87ao 

animal 53b20 / 66a35 

antelope 63a 10 

ants oOb^o / 78b 15 / 83a5 

Aorta 52b25/66b25/67bl5ff 
/71bl5 / 77a5/ 78al 

ape 89b30 
appendage 70a30 
Aquinas, St Thomas 42 
Arcadia 73a 15 
Aristotle, " lantern " of 

art 39b 15 / 40a25 
Ascidian 80a5 / 81al0, 25 f 
ass 67a20 / 88b20 

" Indian " ass 63al5 
Astaci 83b25 flf 
attributes, "essential" (or 

" inseparable") 43a25 / 

45b 1 
auditory passages 57a 15 

backbone 51b30 / 52al0 / 
54b 10 



backward-grazing oxen 

59a 15 
Bacon, Francis 58b 15 
barn-door fowls 57b25 
bat 97bl ff 

Batos 95b25 / 96a25 / 97a5 
beak 59bl ff / 

62a30ff/92bl5 /93al0f 
bear 58b 1 

beautiful, the 45a25 
bee 48a5 / 501 v25 / 61a20 / 

78blOf / S2bl0 / 83a5, 

beetle, see dung-heetle 
belly 55al 
bending 54b5 / 83b], 30 / 

87b25f / 89alO / 93bl 
Bergson 3 

bile 49b30. See also gall 
birds 42bl0 / 57b5, 15 / 

59blff /60a25 / 74bl5ff / 

76a30 / 91a20 / 92b 1 ff / 

bison 63a 10 
bivalves 79bl5ff 
Black Sea 82a25 
bladder 70b25ff / 71bl5, 25 / 

"blend" 31 / 37 / 38 / 39 / 

50b25 / 52b25, 35 / 69a 10 / 

73b30 / 86a 10 
blinking 57a35, bl5f / 91a20 
blood 4 / 45b5 / 47b 1 (current 

of), 30 ff / 49a 15, b20 / 

50a30ff / 51al0 / 56bl / 

66b25f /67bl5ff / 78a5 
blood-vessels 47b5 / 50a25 f / 

52b30 /54bl /65bl0f,25 / 

661)25 / 67bl5ff 
Great Blood-vessel 52b25 / 

66b25 / 67bl5ff / 71bl / 

blooded animals 22 / 42bl0 / 

50b25 / 65a25 / 76bl0f / 

78a5 / 85b35 ff 
bloodless animals 22 / 23 / 

42b 10 / 50b25 / 73a30 / 

blowhole 59bl5 / 97al5 ff 
boar 51al 
Bonasus 63a 10 
bone52alff / 53b30ff / 

54a30ff / 66b 15 
Bovle, R. 45a6 
brain 52a20ff / 56alOff / 

58bl / 73bl0 / 86a5 
breast 88alOff 
breathing-machine 59a5 
bregma 53a 35 
bronchial tubes 64a25 
bull 5lal / 63a35 
buttocks 89b5 ff 

caecal appendages 75al0 
caecal dilatation 75b5 
Calamary 54a20 / 78b30 / 

79al5 / 85al0ff, bl5 
camel 63al / 74a30 / 76b25 / 

77a35 / 88b20 / 89a30 
Canthari 82b25 
Carabi, caraboids 79a30f / 

83b25 ff 
Carcini 83b25ff 
Caria 73a 15 
Carides 83b25 ff 
carnivorous animals 55al0 / 

61b5 / 62bl / 93a 1 / 97al 
Cartesian co-ordinates 20 
cartilage 54b25 / 55a30 
catamenia 48a30 / 89a 10 
cattle-flics 61a20 
Causes 3 / 8 / 11 /21 /24ff/ 

39bl0ff / 40b5 / 41a25 / 

46a 10 
cavities 66b20 ff 
centipede 82a5, bl 


Cephalopods 23 / 54a 10 / 

78a25 if, h25 ff / 84b5 tf 
Cercidas 73a 15 
Cestreus 75al0 / 96a5 
Cetacea 69a5 / 97al5ff 
Chalcis in Euboea 77a 1 
chamaeleon 92a20 
chance 40a30 / 41b20 / 45a20 
ciliarv motion 84b20 
classification 18 / 20 / 42b5 if / 

43b 10 if 
claws 62b 1 / 83b30 f / 84a 15, 

cloven hoof 74a25 / and 

cockchafer 82b 15 
"coUiquescence" 38 / 77alO 
colon 75b5, 15 
connnon functions to body 

and soul 9 / 48a35 
components in isolation 45a35 
" composition " 4 / 46alO S 
composition of Aristotle's 

works 10 
" concoction " 31 / 34 / 50a5 / 

51a20, b25 / 52a5 / 68b5/ 

70a20, 25/72al /75alOf/ 

77b25 f 
connate pneuma 59bl5 / 69a 1 
controllinc: part 73b 10 / 

81bl5 if/ 82bl,25 / 86al5 
Cook, A. B. 73al5 
cooling 56a20 / 62al5 / 

68b35 ff / 92a20 / 96b20 
copulation 89a5, 25 
Cordylus 95b25 
couvre-feu 54a5 
crab 79a30 / 91bl5 
Crex 95a20 
crocodile 60b25 f / 90b30 / 

91al5, b5 flF 
crop 74b20 if / 78b30 f 
crow 62b5 

Crustacea 23 / 54al / 57b30 / 

78a25 if / 83b25 fiF 
cuttlefish 54a20. See also 

Cuvier 44 / 84b 15 
Cyprinoi 60b35 

Darwin 4/7 

/ 67a20 / 77a30 / 88b25 
deformed animals 57a20 / 

60b25 / 84bl / 95b 1 
Democritus 40b30 f / 42a25 / 

derivation of words 62b20 / 

diaphragm 70a5 / 72bl0 if 
dichotomy 18 / 42b5 ff 
differentiae 42b20 if 
disadvantageous parts 48al5/ 

59al5 / 63a5 / 64a5 / 94al5 
Dissections 50a30 / 66a5 / 

divers 59 a 5 

divine things 44b25 ff / 56a5 
" division of labour " 83a20 / 

dog74al / 75a25 / 88a5, bl 

Indian dog 43b5 
dog-teeth 61blO 
dolphin 55a 15 / 69a5 / 77a35 / 

96b25 / 97al5 
dualitv of the bodv 56b30 / 

63a20 / 67b30 / 69bl0ff 
dung 75b30 
dung-beetle 82b25 
dwarf-like 86bl ff / 89b25/ 

dynamis 29 / 30-32 / 40a20 / 

46al0, bl5 if / 47b5 / 55bl0 


ears 57a 10 ff 
earth 51a25 



earthy matter 6.Sb25 fT etc. 
editions of Aristotle's De 

part thus 44-45 
Edwards, Milne 83a20 
eel 96al, b20 

eggs 65a35 / 84a20 / 92al5 
" Elements " 30 / 42a20 / 

46al0, b5 / 47al0 / 48bl0 
elephant o8b30if / 61a25 / 

63a 1 / 83b30 / 88b5, 15 / 

embrvo 51b20 / 55al / 65bl / 

66a20 / 71b5 / 76al5 
Empedocles 40a20, b5 / 

42al5 / 48a30 
Emys 71a30 
epiglottis 64b20 ff 
epipetron 81a20 
equivalents, law of organic 

" excess and defect " (" the 

more and less ") 19 / 44a20, 

bl5 / 49a30 / 55a30 / 

61b30ff / 84a30 / 92b5 
excrement 63a 15. See 

excretory organs 89a5 ff 
eye and eyelid 57a25 ff/ 

eyebrows 58blOff 
eyelashes 58al0ff 

Fabricius 43 

fat51a20ff / 72al 

fear 50b25 / 67al5 f / 79a25 / 

82b25 / 92a20 
feathers 92b 10 
fibres 50b 10, 30 
fin 85bl5 /95b35ff 
Final Cause 21 /39bl5ff/ 

fire 49a20 / 50a5 ff / 52b5 
fishes 42bl0 / 58al / 60bl0 ff, 


76a25, b20 / 95bl ff 
fishing-frog 95b 10 / 96a25 
fishing-rod 93a20 
flea 83a30 
flesh 47a20 / 51b5 / 53bl5 ff / 

60a5 f / 68a25 ff 
fly 61a20 / 78bl5 / 82bl0 / 

fluid and solid 32 / 46a 15 
flax 52b30 

fontanel, anterior 53a35 
foot 82a35ff / 85al0ff/ 

90a25 ff 
foreskin 57b 1 
form (and matter) 9/11 / 25 / 

40al5, b20 / 41al5 
formation (process of) 27 / 

40al0ff / 46a25 
funnel 79al 

gadflies 61a20 

gall and gall-bladder 5 / 

gazelle 50bl5 / 63a 10, b25 
gills 59bl5 / 96bl ff / 97al5f 
qladius 54a20 

goat 73b30 / 74b5 / 76b35 f / 
' 88b25 
Goethe 84b 15 
good, the 39b20 / 59b30 / 

" good life " 56a5 
" goodness " {arete) 42a30 
goosefish 95b 10 / 96a25 
grasshopper 82al5f 
grease 51a25 
Great Blood-vessel, see under 

Grosseteste, Richard 41 
gut 74al0 / 75a30f 

haematoporphyria 68b5 


haemorrhage 68bl5 

hair o8alo flf 

hand 87a5ff, bl flf / 90a30 

hare 67a20 / 69b30 / 76al5 

Harun-al-Rashid 40 

Harvev, WilUam 43 / 44 

hawk 70b 1 

head 5(jal0 ff / 58bl / 86a5 ff 

hearing 56b 10 

heart 47a25 / 53b5 / 54b 10 / 

56a25 / 65al0, blOff / 

7T)a20f / 73b 10 ' 77bl / 

78bl / 8Gal5 / 96bl5 
heat 53b5 / 96bl5 / and 

hepatopancreas, see mecon 
Heraoleitus 45al5 
Heracieotic crabs 84a 10 
Herodotus 59al5 
Hippocrates 30 / 31 / 37 / 

40b 15 / 4Sal / 50b20 / 

85b5 / 86b25 
Historia Animalium 46a5 / 

oOaSO / 60bl / 74b 15 / 

SOal / 84b5 / 89a 15 / 

Holothuria 8 la 15 
Homer 73al5 
hoof 90a5 ff 
horned animals 73b30 
horns 62b20 ff 
horse 63al / 66bl5 / 88b20, 

hot, the 50a5 flf 
hot and cold 4 lb 15 / 46a 15 / 

hucklebone 51a30 / 54b20 / 

hyaena 67a20 

" idly " (" Nature does no- 
thing idlv") 61b20 / 91bl / 
94al5 / 95bl5 

immortality 37 

" Indian ass " C3Hl5f 

ink 79a 1 ff/ 81b25 

Insects 23 / 54a25 / 57b35 / 

59bl5 / 78bl0 / 82al flf 
instruments, instrumental 

parts 30 / 45b 15, 25 / 46b25 

/ 47al ff, b20 / 87a5 ff 
intelligence 48al / 50b20 / 

72a30 / 86a25 f / 87a5 
intermediate creatures 23 / 

69alO / 81alO, blO / 

89b30 / 97al5 ff 
" internal finahtv " 3 
intestines 50al5 / 74al0 ff / 

75bl flf/ 76bl0 
irrigation 68al0 f 
j ischium 95al ff 

I jaws 91a25 ff 
jejunum 75b25 ff 
joints 54b 15. See also 

Kerkidas 73al5 
Kestreus 75al0 / 96a5 
kidney 70al5, b20 / 71a25 ff 
kite 70b 1 
Knides 81a35 
Ktesias 63a 15 

" lantern of Aristotle " 80a5 
lard 51a20 ff, b25 / 72a5 
laymx 64al5 ff 
laughter 73a 1 ff 
Lee, H. D. P. 10 
Leonardo da Vinci 65b5 
leopard 67a20 / S8a5 
Lesbos 80b 1 
life 55b35 / 78bl 
limpet 79b25 / 80a20 
lion 51b35 / 55al0 / 58a30 / 
86a20 / 88a5, bl/89a30 



lips 50b20 

liver 66a25f^ I 69bi?5ff/ 

73bl5ff/77alo, :?5f, b35 
lizard 76a25 /91a5ff 
** lizards " (aavpai, plaited 

tubes) 85b5 
lobster 84a30 
locust 83a30 
logos 26f /39bl5 /40a30 / 

42a20 / 46b 1 / 49b25/ 

78a35 / 95bl5 
Lophiva piscatorhts 95blO 
lumen 71bl 

lung 64a20 f / 65a 15 / 68b30 ff 
lynx 89a30 

Maia 84al0 

mammae 88al5ff 

Man 44a 1 / 45b25 / 53a25 ff / 
56a5 / 58al5, bl / 59b80 / 
eOalOif / 61b5 / 62bl5 / 
66b5 / 69a20, b5 / 71bl / 
73a5, 25/76b30/86a25ff/ 
88b30 / 89b5ff / 90a25 / 

marrow 51b20fF 

marten 67a20 

matter and form 9/35/36 

mecon 79b 10 / 80a20 

melanin 34 

Melolontha 82b 15 

membrane 73b Iff /77b 15, 35/ 
82b 15 /83b20 / 9la20 

mesentery 50a25 / 76blO / 
77b35 ff 

Methydrion 73a 15 

metre 60a5 

mice 67a20 / 76b30 

Michael Scot 40 ff / 46-47 

migrants 94a5 

milk76al0f /88bl 

moderation 52b 15 

Moerbeke, William of 42 


moon, full 80a30 

mouth 50al0ff / 62al5ff 

96b20 ff 
Murex 61a20 
mussel 79b25 / 83b 15 
mytis 79a5 / 81b20ff 

nails 87b20 / 90b5 

Natural science 39a 10 / 40a 

" Natural Selection " 4 

Nature 39bl5/ 41 a25, blOff^ 
42a 15 / and passim 

Naxos 77al 

Necessity 21 / 39b20ff / 
42a Iff, 30 ff / 45b30 / 
46b25 / 51al5 / 63b20 / 
70a30, b20 / 72b30 / 77a 1 5 , 
85bl5 / 92a 1 / 94b5 

neck 64al0/86a5ff/92b20ff 

Nerites 79b20 

nictitating membrane 57a30 

" non-uniform " parts 28-30 / 
46a20, b5, 30 / 47a25 / 
55b25 ff 

nostrils 58b25 ff 

nutriment (" ultimate ") 
50a30 / 51al5 / 7Sa5, 15 

nutrition 47a25 / 50a35 

octopus 52b25 / 54a20 / 
78b25 / 79a5ff / 85a5,15 ff 

oesophagus 50al5 / 64a 15 ff / 
74al0, b20 / 86a20 / 

omasum 74b 15 / 76ai0f 

omentum 76bl0 / 77b 15 

opercvlxnn 79b 15 

opposites, division by 43a30 

orifice 81a25 

Oryx 63a20 

OS sepiae 54a20 

Ostreae 80b20 


ostrich 58a 10 / 95al5 / 

"ova" SOalOff, biff 
ox 66bl5 / 71b5 / 88b25 

oyster 80b5, 20 / SlblO 

Parmenides 48a25 
Parnassus 81a20 
parrot-fish 62ao / 75al 
"part" 28-30 / 51b25 / 64a5 / 

passages 50alo / 56bl5 / 

71bl, lOff / 78alO 
" pen " of Calamary 54a20 
penis 89a20 f 
" perfect " animals 55b30/ 

66a25 / 82a30 
philosophers, early 40b5 / 

" philosophical treatises " 

phlegm 53al / 77b5 
pigeon 70bl 
plants 50a20 / 55b30 / 78 alO / 

81al5 fF / 82b30 / 83bl5 / 

Plato 30 / 42bo / 45a35 / 

51b20 / 69al5 / 76b25 
pneumaf connate 59b 15 / 

"potentiality" 43al / 47a5 / 

49b Iff/ 67b20 / 68a30 
" pounce " (of cuttlefish) 

privative terms, privation 

42b20ff / 49a 15 
proboscis 78b 10 / 79a5 / 

85a30, blO 
Protagoras 42a25 
purpose 45a20 / 51al5 / 

63b20 / 70b20 / 77al5 / 

78al5 / 92al 

Purpura 61a20 / 79bl5f 
Pyrrha, strait of 80b 1 
Pythagoreans 70b20 

rain 53a 1 

razor-fishes 83b 15 

" realization " 35 ff 

relative size of parts 65b5 

rennet 76a5 ff 

residue 29 / 32-34 / 47b25 / 

50a20 / 70b25 / 71a5 / 

74al5 / 75bl0ff / 76a30 / 

77alOf, 25 / 81a30 
respiration 5 / 42a30 / 62al5 / 

64b 1 / 65a 15 
reticulum 74b 15 / 76a5 
Rhine 97a5 
rhinoceros 63a 15 
ribs 55al 

Ris-us Sardonicus 73alO 
rot 72a30 ff 
rumen 74bl5 
rumination, ruminants 74b5 / 

75al f 

St-Hilaire, J.Barthelemv- 44/ 

St-Hilaire, G. 84bl5 
saw-teeth 6 lb 15 / 62a5 
scales 91al5 
scallops 79b25 / 80b20 / 

Scarus 62a5 / 75al 
scorpion 83a 10 
sea-anemone 81a35 
sea-cucumber 81al5 
sea-lung 81al5 
sea-nettle 81a35 
sea-sickness 64b 10 
sea-snail 78b20 / 79b5 
sea-squirt 81alO 
sea-urchin 79b25f/ 80a Iff, 30, 

bl ff / 83bl0 



seal57a20/71b5/76b:23 / 

seed 41b25 / 89a5f 
Selachia 4 / 55a20, 25, 3o / 

76bl /95b5/96blflF/97a.-> 
self-defence 55b5 / 62b25 etc. 
semen 51bl0, 20 / 89a5f 
sensation 47a 1 If / 48a 1 / 

50b25/51alO, bl I 5Sb~2() I 

5Gal, 15/ 66a35 / 72b30 / 

sense, " general " 86a30 
sense-organs 47a5 / 56b35 
senses 56a25 if / 86alO 
Sepia 54a20 / 78b25 / 79a5 ff / 

septum 81a30 
serpents 60b5 / 76a25, b^20 / 

90bl5ff / 91b25ff /96a5 / 

serum 51al5 / 53a 1 
Shakespeare 33 / 34 
sheep 7 1 b5 / 72a25 if / 73b30 / 

76b35 f 
sheep-rot 72a30 if 
sinews 66b 10 / 96b5 
Siphae 96a5 
sleep 53a 10 
smell 59b 15 
Smyraena 96a5 
snake 91al5 
Socrates 42a25 
solid and fluid 47a30, blO / 

48bl /49bl0if 
solidification 49a30 / 51alO 
Soul 9/ 34-37/ 38 /41a 15 if/ 

50b25 / 52b5f / 67b20 / 

72b 15 / 76b25 / 78b 1 / 

86b25 / 92a20 
sounds 60al f 
speech 59b30 if / 60a20/ 

61bl5 / 64bl / 73a20 
spider-crab 84al0 

spiral shells 79b 10 
spit-and-lampstand 83a25 
spleen 66a25 / 69b25 if / 

70a30 if, bSO 
sponge 81alOf 
spontaneous production 

spurs 94a 10 
starfish 81b5f 
sterility 51b 10 

sting 61 al5, 25 / 82al0, b30 flf 
stomach 74a5 if / 80b25 if / 

stone 67b 1 
substratum 49al5f 
suckers 85b 10 
suet 51a20if, b25 / 72a5 
sutures 53a35 / 58b 1 / 67a5 
sweat 68b 1 

swine 63a5 / 88bl, 10 etc. 
symmftria 52b35 / 8Gal0 
systoichia, 70b20 

tail 58a30 / 84al / 89bl if / 

talons 94al5 
taste 56b35 / 60a20 / 61a5 / 

90b25 if 
Taylor, Prof. A. E. 20 
teeth 55b5 / 61a30 flf / 78bl5 / 

teleology 3 / 48al5 / 59al5 / 

63a 10 / 94a20 
tentacles 85b 1 f 
Testacea 23 / 54a 1 / 78b 10, 20 

/ 79bl if / 83bl if 
testicles 95a25 / 97alO 
text and manuscripts of De 

partibus 45 if 
theoretical sciences 40a 
Thompson, Prof. D'Arcy 10 / 

19 / 20 / 44a20 
Tipha 96a5 


tissues 4 

toad 73b30 

Toledo 40/41 

tongue o9b35 if / 78b5 ff / 

901);20 if 
torpedo-fish 95b5 / 96a25 f 
tortoise 54a5 / 71al5f / 

73b30 / 76a30 / 91al5 
touch 47 / 53b20 / 56a35 
Transformations, theory of 

19 / 20 
translations of Aristotle's 

works 39-43 / 44-45 
transmigration 36 
troglodytes 69b5 / 84a5 
Trvgon 9obo, 25 
tube-feet 81a5 
turtle 54a5 
tusks 55b 10 

umbilical cord 93b25 

umbilicus 93b20 

" uniform " parts 28-30 / 

40b20 / 46a20, b5, 30 / 

47a25, blO 
upright posture 53a30 / 56a 10 

/ 58a20 / 62b20 / 69b5 / 

86a25if / 87a5 / 89blOif / 

90a25 / 95al if 
ureters 7 lb 15 

vaporization 52b35 / 72b 15 

variations in " parts " 47b25 ff 
/ 73bl0if 

ventilation 53b 1 

vermiform appendix 75a 15 

vertebrae 51b30 / 54b 15 / 

Vertebrates and Inverte- 
brates 45b 10 

viper 76bl f 

viscera 47a30 / 65a25 ff / 

Vivipara 55a5, blO / 62lv20 / 
73bl5/ 74a25 / 85b35ff 

wasp 83a5 

whale 69a5 / 97al5ff 
whelk 79bl5f/ 831)10 
windpipe 64a35 if ' 86a 15 
wing (of birds) 93b 1 if 
wing (of insects) 82b5 ff 
wolf 86a20 / 88a5 
woodpecker 62b5 
wryneck 95a20 

xanthopterine 34 

Zeus hoplosmios 73a 15 
zoological works of Aris- 
totle 8 



Note: 98a-99b = 698a-699b 
00a-14b = 700a-7Ub. 

The matter contained in lines 1-5, 5-10 etc. is treated as a 
section, and each section is referred to by the number of its 
first line : e.g. 98a 1 refers to anything contained in page 
698a lines 1-4, and 13bl0 to anything contained in page 
713b lines 10-14. 

action, the result of the prac- 
tical syllogism 01a22 If 

active )( passive 02b 10 / 

alteration, causes of Olblo 

animals passim 

appetite 00b 10 

arms, movement of, in run- 
ning 05al5 

athletes, use of weights in 
jumping by 05al5 

Atlas, the fable of 99a25, bl 

back )( front, of animals 
05a25, blO 

bat 14bl0 

bees 10a 10 

beetles lOalO 

bending, as a means of 
motion 07b5 / 08b20 ff / 
09b 1 ; concave and convex 
ib. 10 ; of legs in walking 


by man lla25 ff, by quad- 
rupeds ib. blO, by birds 

bipeds 04al0, 15 / 06a25, 
bl ff / 10b5 / 12b30 

birds 09b20 ; are bipeds 
06a25 ; standing position 
of 10bl5 ff ; compared with 
fishes 14a20 ff ; birds with 
talons the swiftest flyers 
10a25 ; web-footed birds, 

bloodless animals, progres- 
sion of 12b20 ff; struc- 
ture of ib. 30 ; can have 
more than four feet 08al5 ; 
can live though divided in 
parts 07a30 

boat, illustration from a 

bones 01b5 

Boreas 98b25 


bronze, horses in 10b20 

caterpillars, 05b25 / 09a30 
children, their difficulty in 

walking 10b 10 
cockchafer 10a 10 
conger-eels 08al 
crabs 12bl0/ 14bl5; curious 

structure of ISblO flf 
crawling 09a5, 25 
crocodile 13a 15, bl5 
cupids, pictures of winged 


De anima, referred to 00b5 / 

Be parfibus animalium, re- 
ferred to 98al 

desire, as a cause of motion 
00bl5/01al/03a5; absent 
in involuntary movements 
03b 10 

diagonal movement of the 
legs 04bl / 12a20, b5 

dimensions of animals 04bl5 / 

earth, immobility of the 

99a30, b5 ff 
earthworms 05b25 
eels 08al ff / 09blO 
elbow 12al0 ; elbow-joint 

98b 1 / 02a25 
elephant 09al0 / 12al0 

feet, even number of, in all 
animals 04al5 / 08a20 ff 

fiery element 03a20 

fire, movement of 99b25 / 
00a 10 

fishes 09b30 / 13b5 ; com- 
pared with birds 14a20 ff 

flat-fish 09bl0 / 14a5 

flying 98a5, b]5 / 09b5 
" foot," defined 06a30 
footless animals 04al0 / 

05b20 / 06b 1 ; movement 

of 07b5 / 09a25 
fore-arm 98bl / 02a25 
fowls, domestic 10a5 

geometrical illustrations 
98al0 / 02b25 / 03b25 

good, the, as a cause of move- 
ment 00b25 ; real )( appar- 
ent good, ib. 

hand 02a30 ff 

heart 03al0 / 03b5, 20 

heavens, movement of the 

heron 10a 10 
hips 98b5 / 09al0 / lla5; of 

birds 10b20, of man ib. 
Historia animalium, referred 

to 04b 10 
Homer, quoted {Od. viii. 20- 

22) 99b35 
hopping 0ob30 
horses, of bronze 10b20, in 

religious processions 12a30 

" impossible," meaning of 

imagination OOblO / Olblo / 

02al5 / 03bl0 ff 
inferior )( superior parts 

04b20 / 05a25 / 06bl ff / 

insects 09b30 / 10a5 ff/ 13al 
intellect 00b 10 

joints 98al5 / 02a20 / 03al0 / 
05al5; of elbow 98bl 

jumping 05a5, 15 / 08a20 / 
09 b5 



knee 98bl 

lampreys 08al 

leeches OOaSO 

left )( right 05a25, bl5 ff ; 
left and right sides of 
the body, similar 02bl0 ; 
weights carried on left 
shoulder OobSO ; why men 
step off with the left foot 

legs, the 98b5 / lOblO ; posi- 
tion of, in movement 
OOblo if; of man, bent if. 
convex direction O-lalS, of 
birds, in a concave direc- 
tion ib. 20 ; four ways of 
bending the legs 12a I : 
transference of weight from 
one leg to another llalO : 
of polypods 13b25 ff: 
necessary to birds 09b20 : 
used to direct flight 

lizards 13b 15 

lobster lSb20 ff 

man, the only erect animal 
10b 10; right-handed 06a20: 
why a biped 04a 15 ; why 
not winged llal ; his 
action in walking 07bl5 ; 
bends his legs in a convex 
direction 04-al5 

marionettes, illustration from 

Metaphysics^ referred to 

mice 98b 15 

molluscs 06a30 

moon 99b 15 

motion, movement, of tlie 


universe 98b 10, of the 
heavens 99a 10, blO, of 
animate things OOblO, of 
inanimate things OOblO, 
of the soul 00b 1, of red- 
blooded footless animals 
07b5 ; various kinds of 
movement 98a5 / Ooal ff; 
cause of movement 00b 15 ff; 
where situated 02a20, bo ff ; 
ori^:in of movement 98al5, 
bl^ ff / OlbSO / 06bl5; 
points at which movem.ent 
takes place 04-alO /0ral5 ff, 
b5 ff / 09b20 ; movement 
begins on the right side 
05b30 / 06b 15 ; movement 
implies something at rest 
outside 99b30 / 02a25 : 
movement of one part 
necessitates rest of another 
part 98al5, bl ff / 00a5 : 
movement by bending 
08b20 ff / 09bl / lla5 : 
voluntary )( involuntary 
movement 03b5 ; diagonal 
movement of the legs 
04bl / I2a20, b5: move- 
ment in jumping, running, 
and walking 05a5 ff 

mover, the prime OObo, 
moves without being itself 
moved 98a5 / 00b35, is 
eternal OObSO 

mullet OSal 

nature, creates nothing with- 
out a purpose 04b 15 / 
08a 10, creates nothing un- 
natural lla5 

nutrition, of plants 06b5, of 
plants and animals com- 
pared 05b5 


opposite parts of the body 
move simultaneously 02b 1 ( ) 

oviparous quadrupeds 04b 1 / 

passive )( active 02a 10 / 

peacock lOao, 20 
Physics, reference to (258b49 ) 

98a 10 
plants, nutrition of 06b5, lack 

movement ib., compared 

with animalsOobo, superior 

and inferior parts of 05a25, 

points at which movement 

takes place 04-alO /07a 15 if, 

b5 if / 09b20 
poles, the 99a20 ff 
polvpods 04a 10 / 06a30, bo / 

OSbl / 12bl0 / 13a25, bio 
porphjTio (a bird) 10a 10 
procession, religious 12a30 
purple-fish 06a 15 
purpose 00b 10 / 01a5, in 

nature 04b 15 / 08a 10 

quadrupeds OlalO ff /06a30 / 
07bl5; bending of the legs 
of quadrupeds in walking 
llblO; oviparous quad- 
rupeds 04b 1 

ray (fish) 09b 15 

red-blooded animals llao, 
move at four points 04a 10 / 
07al5, b5/09b20, cannot 
live if divided into parls 

resistance of earth, air or sea 
necessary to movement 

rest )( motion 98b5 

right )( left 05a25, bl / 
06b25 / 07a5 ; movement 
originates on the right side 
0ob30/06bl5; right side 
superior to left 06a20, 
blO ; right limbs used in 
defence 06a5 

roots of plants 05b5 

rudder, slight movement of, 
changes direction of boat 

scolopendrae 07a30 / 08b5 

seal 14b 10 

sensation 01a35, cause of 
alteration 01b 15 ; origin 
of sensation situated in tiie 
centre of the body 02b20 

sense-perception, in animals 
05b 10: objects of 98a 10 

sexual organs 03b5, 20 

shin 98b 1 

shoulder 98 bl / 09a 10 / 1 la.3 / 

sinews 01b5 

Siphae 08a5 

snakes 05b25 / 09a25, move- 
ment of 07b20 ff, why 
footless 08ao ff 

soul, movement of the 90bl, 
central position of 03a3o, 
as origin of movement 
02bl ff / 03al 

spine 02b20 

spirit, innate, in animals 
03al0 ff 

stromboid testaceans 06al0, 

superior )( inferior parts 

swimming 98a5, bl5 / 091)5 

syllogism, the practical 
OlalO ff 



tail, used as a rudder lOal 
talons, birds with, the swiftest 

tlyers 10a25 
testaceans 06alO, bl / 14b5 
thighs 12a 15, of birds 12b30 
Tityos 98b25 
tortoise 13a 15 
toy-carriage, illustration from 

trumpet-shell 06a 15 

universe, movement of the 

viviparous quadrupeds 04a20 
voluntary )( involuntary 
movement 03b5 

walking 05a5 

wasps 10a 10 

water-fowl 10a 10 

web-footed birds 14a5 

weights, used by athletes 
when jumping 05al5, 
carried on left shoulder 

w ings 05b20 / 06a25 / 09b5, 
30 ; of birds, necessary for 
walking 09b20, and for 
standing 10b30, serve as 
front legs 12b20; ofcupids, 
useless Hal ; of insects 
10al5 ; grow obliquely 

wrestling-school 09blO 

wrist 02b 1 

Printed in Great Britain by R, 

R. CiARK, LiMiTtD, Edinburgh 





Ammianus Marcellinus. J. C. Rolfe. 3 Vols. 

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St. Augustine, Confessions of. W. Watts (1631). 2 Vols. 
St. Augustine : Select Letters. J. H. Baxter. 
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BoETHius : Tracts and De Consolatione Philosophiae. 

Rev. H. F. Stewart and E. K. Rand. 
Caesar : Alexandrian, African and Spanish Wars. A. G. 

Caesar : Civil Wars. A. G. Peskett. 
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Cato and Varro : De Re Rustica. H. B. Ash and W. D. 

Catullus. F. W. Cornish ; Tibullus. J. B. Postgate ; and 

Pervigilium Veneris. J. W. Mackail. 
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Cicero : Brutus and Orator. G. L. Hendrickson and 

H. M. Hubbell. 
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Cicero : De Natuha Deohum and Academica. H. Rack- 
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De Oratore, Book III : De Fato ; Pahadoxa Stoi- 

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Clinton W. Keyes. 
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W. A. Falconer. 
CiCKRo : In Catilinam, Pro Mubena, Pro Sulla, Pro 

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Pro Rabirio. H. Grose Hodge. 
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Balbo. R. Gardner. 
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Comoedo, Contra Rullum. J. H. Freese. 
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Claudian. M. Platnauer. 2 Vols. 
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E. S. Forster, E. Heffner. 3 Vols. 
CuRTius, Q. : History of Alexander. J. C. Rolfe. 2 Vols. 
Florus. E. S. Forster ; and Cornelius Nepos. J. C. Rolfe. 
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and M. B. McElwain. 
Fronto : Correspondence. C. R. Haines. 2 Vols. 
Gellius. J. C. Rolfe. 3 Vols. 
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LucAN. J. D. Duflf. 

Lucretius. W. H. U. Rouse. 

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Minor Latin Poets : from Publtlius Strcs to Rutilius 
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other poems. J. Wight Duff and Arnold M. Duff. 

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Petronius. IVl. Heseltine ; Seneca : Apocolocyntosis. 
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Plautus. Paul Nixon. 5 Vols. 

Pliny : Letters. Melmoth's translation revised by 
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Phopertius. H. E. Butler. 

Prudentius. H. J. Thomson. 2 Vols. 

Quintilian. H. E. Butler. 4 Vols. 

Remains of Old Latin. E. H. Warmington. 4 Vols. 
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Sallust. J. C. Rolfe. 


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SiDONius : Poems and Letters. W\ B. Anderson. 2 Vols. 

SiLius Italicus. J. D. Duff. 2 Vols. 

Statius. J. H. Mozlev. 2 Vols. 

Suetonius. J. C. Rolfe. 2 Vols. 

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F. W. Shipley. 
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Aeneas Tacticus, Asclepiodotus and Onasandeb. The 
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Apollodorus. Sir James G. Frazer. 2 Vols. 

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Appian s Roman History. Horace White. 4 Vols. 

Ahatus. Cf. Callimachus. 

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Iliffe Robson. 2 Vols. 

Athenaeus : Deipnosophistae. C. B. Gulick. 7 Vols. 

St. Basil : Letters. R. J. Deferrari. 4 Vols. 

Callimachus : Fragments. C. A. Trypanis. 

Callimachus : Hymns and Epigrams, and Lycophron. 
A. W. Mair ; Aratus. G. R. Main 

Clement of Alexandria, Rev. G. W. Butterworth. 



Demosthenes I : Olynthiacs, Philippics and Minor 

Orations : I-XVII and XX. J. H. Vince. 
Demosthenes II : De Corona and De Falsa Legatione. 

C. A. Vince and J. H. Vince. 
Demosthenes III : Meidias, Androtion, Aristocrates, 

Timocrates, Aristogeiton. J. H. \'inGe. 
Demosthenes IV-VI : Private Orations and In Neaeram. 

A. T. Murray. 
Demosthenes VII : Funeral Speech, Erotic Essay, 

Exordia and Letters. N. W. and X. J. DeWitt 


Dio Cassius : Roman History. E. Gary. 9 Vols. 

Dio CiiRYsosTOM. 5 Vols. Vols. I and II. J. W. Cohoon. 

Vol. III. J. \V. Cohoon and H. Lamar Crosby. Vols. IV 

and V. H. Lamar Crosby. 
DioDORUs SicuLus. 12 Vols. Vols. I-VI. C. H. Oldfather. 

\^ol. VII. C. L. Sherman. Vols. IX and X. Kussel M. 

Geer. Vol. XT. F. R. Walton. 
Diogenes Laertius. R. D. Hicks. 2 Vols. 


man's translation revised by E. Cary. 7 Vols. 
Epictetus. W. A. Oldfather." 2 Vols^ 
Euripides. A. S. Way. 4 Vols. \'^erse trans. 
EusEBius : Ecclesiastical History. Kirsopp Lake and 

J. E. L. Oulton. 2 Vols. 
Galen : On the Natural Faculties. A. J. Brock. 
The Greek Anthology. W. R. Paton. 5 Vols. 
The Greek Bucolic Pokts (Theocritus, Bion, Moschus). 

J. M. Edmonds. 
Greek Elegy and Iambus with the Anacreontea. J. M. 

Edmonds. 2 Vols. 
Greek Mathematical Works. Ivor Thomas. 2 Vols. 
Herodes. Cf. Theophrastus : Characters. 
Herodotus. A. D. Godley. 4 Vols. 
Hesiod and the Homeric Hymns. H. G. Evelyn White. 
Hippocrates and the Fragments of Heracleitus. W. H. S. 

Jones and E. T. Withington. 4 Vols. 
Homer : Iliad. A. T. Murray. 2 Vols. 
Homer : Odyssey. A. T. Murray. 2 Vols. 
IsAEUS. E. S. Forster. 

Isocrates. George Norlin and LaRue Van Hook. 3 Vols. 
St. John Damascene : Barlaam and Ioasaph. Rev. G. R. 

^^'oodward and Harold Mattingly. 
JosEPHUS. H. St. J. Thackeray and Ralph Marcus. 9 Vols. 

Vols. I-VII. 
Julian. Wilmer Cave Wright. 3 V^ols. 
LoNGUs : Daphnis and Chloe. Thornley's translation 

revised by J. M. Edmonds; and Pahthenius. S. Gase- 

LuciAN. A. M. Harmon. 8 Vols. Vols. I-V. 
Lycophron. Cf. Callimachus. 
Lyra Graeca J. M. Edmonds. 3 Vols. 
LrsiAs. W. R. M. Lamb. 


Manetiio. W. G. Waddell; Ptolemy: Teteabiblos. F. E. 

Marcus Aurelius. C. R. Haines. 
Mexander. F. G. Allinson. 
Minor Attic Orators. 2 Vols. K. J. Maidment and 

J. O. Burtt. 
NoNNos : DioNYsiACA. W. H. D. Rouse. 3 Vols. 
Oppian, Colluthus, Trytiiiodorus. a. W. Mair. 
Papyri. Nox-Literary Selections. A. S. Hunt and C. C. 

Edgar. 2 Vols. Literary Selections (Poetry). D. L. 



Pausanias : Description of Greece. W. H. S. Jones. 5 

Vols, and Companion Vol. arranged by R. E. Wycherley. 
Philo. 10 Vols. Vok. I-V. F. H. Colson and Rev. G. H. 

Whitaker ; Vols. VI-IX. F. H. Colson. 

Two Supplementary \'ols. Translation only from an 
Armenian Text. Ralph Marcus. 
Philosteatus : The Life of Apollonius of Tyana. F. C. 

Conybeare. 2 Vols. 
Philostratus : Imagines ; Callistratus : Descriptions. 

A. Fairbanks. 
Philostratus and Eunapius : Lives of the Sophists. 

\\'ilmer Cave Wright. 
Pindar. Sir J. E. Sandys. 
Plato I : Euthyphho, Apology, Crito, Phaedo, Phaedrus. 

H. N. Fowler. 
Plato H : Theaetetus and Sophist. H. N. Fowler. 
Plato III: Statesman, Philebus. H. N. Fowler: Ion. 

W. R. M. Lamb. 
Plato IV : Laches, Protagoras, Meno, Euthydemus. 

W. R. M. Lamb. 
Plato V : Lysis, Syjiposium, Gorgias. W. R. M. Lamb. 
Plato VI : Chatylus, Parmenides, Greater Hippias, 

Lesser Hippias. H. N, Fowler. 
Plato VH : Tl^iaeus, Critias, Clitopho, Mejtexenus, Epi- 

stulae. Rev. R. G. Bury. 
Plato VHI : Charmides, Alcibiades, Hippahchus, Thk 

Lovers, Theages, Minos and Epinomis. W. R. M. Lamb. 
Plato : Laws. Rev. R. G. Bury. 2 Vols. 
Plato : Republic. Paul Shorey. 2 Vols. 
Plutarch : Mohalia. 15 Vols. Vols. I-V. F. C. Babbitt; 


Vol. VI. W. C. Helmbold ; Vol. MI. P. II. De Lacy and 

B. Einarson: Vol. X. H. N. Fowler; Vol. XII. II. 

Cherniss and W. C. Helmbold. 
Plutarch : The Parallel Lives. B. Perrln. II Vols. 
PoLYBius. W. R. Paton. 6 Vols. 

Procopius : History of the Wars. H. B. Dewinj^. 7 Vols. 
Ptolemy : Tetrabiblos. Cf. MANErrno. 
QuiNTUs Smyukaeus, a. S. \Va5\ Verse trans. 
Sextus Empihicus. Rev. R. G. Bury. 4 Vols. 
Sophocles. F. Storr. 2 Vols. Verse trans. 
Strabo : Geography. Horace L. Jones. 8 Vols. 
Iheophrastus : Characters. J.M.Edmonds; Herodes, 

etc. A. D. Knox. 
Theophrastus : Enquiry into Plants. Sir Arthur Hort. 

2 Vols. 
Thucydides. C. F. Smith. 4 Vols. 


Xenophon : Cyropaedia. Walter Miller. 2 Vols. 

Xenophon : Hellenica, Anabasis, Apology, and Sympo- 
sium. C. L. Brownson and O. J. Todd. 3 Vols. 

Xenophon : Memorabilia and Oeconomicus. E. C. Mar- 

Xenophon : Scripta Minora. E. C. Marchant. 



Aristotle : History of Animals. A. L. Peck. 
Plotinus. a. H. Armstrong. 


Babrius and Phaedrus. B. E. Perry. 




Aristoteles ^^^2 

• A? 
Parts of animals, with an *p, ^ 

^glish translation