MAN THE ANIMAL

MAN THE ANIMAL

BY

RAYMOND PEARL

L,ate Processor of Biology

School of Hygiene
Johns Hofkins University

3 Sb c

PRINCIPIA TRESS, INC.

Bloomington Indiana

1946

Copyright 1946, by Indiana University
All rights reserved^ mcluding the refrodiccUon of any fart.

FOREWORD

Dr. Raymond Pearl, Professor of Biology, School of Hygiene
and Public Health, Johns Hopkins University, delivered the-
Patten Foundation Lectures at Indiana University in October,
1938. It was his intention to expand these five lectures before
final publication. Other duties interfered and the work was left
incomplete at the time of his death, November 17, 1940.
Mrs. Pearl, with the help of some of Dr. Pearl's friends, re-
edited the manuscript and gave it to the University in its
present form. In presenting the manuscript, Mrs. Pearl recog-
nized its incompleteness and even its imperfections, for no one
could do the task as Dr. Pearl, himself, would have done it.

F. Payne

ACKNOWLEDGMENT

We are indebted to the following publishers for permission to
use in this book some of the material which has previously ap-
peared either in books or magazine articles written by the late
Raymond Pearl: W. B. Saunders Company, "Medical Biometry
and Statistics/' 1923, 1930 and 1940 editions j Williams and
Wilkins Company, "Studies in Human Biology," 1924; Alfred
A. Knopf, "Alcohol and Longevity," 1926; Paul B. Hoeber,
Inc., "Some Aspects of the Biology of Human Populations,"
in "Human Biology and Racial Welfare," edited by E. V.
Cowdry, 1930; Harper and Brothers, "Patterns for Living
Together," in Harper's Magazine, May, 1938; Science Press,
"The Search for Longevity," in Scientific Monthly, May, 1 939;
Science Press, "Tobacco Smoking and Longevity," in Science,
March 4, 1939; Oxford University Press, "The Natural His-
tory of Population," 1939; and D. Appleton-Century Com-
pany, a reprint of "The Search for Longevity" in "Landmarks
in Medicine" (Laity Lectures of the New York Academy of
Medicine), 1939.

Indiana University
THE PATTEN FOUNDATION

Mr. Will Patten of Indianapolis (A.B., Indiana University,
1893) made in 1931 a gift for the establishment of the Patten
Foundation at his Alma Mater. Under the terms of his gift,
which became available upon the death of Mr. Patten (May 3,
1936), there is to be chosen each year a Visiting Professor who
is to be in residence several weeks during the year. The purpose
of this prescription is to provide an opportunity for members
and friends of the University to enjoy the privilege and ad-
vantage of personal acquaintance with the Visiting Professor.
The Visiting Professor for the Patten Foundation in 1938-1939
was

PROFESSOR RAYMOND PEARL

The present book consists of the Patten Foundation Lectures for
1938-1939.

CONTENTS

Foreword

Acknowledgment vii

The Patten Foundation ix

I. The Unique Mammal

II. The Unique Mammal (continued) .... 22

III. Human Longevity 47

IV. The Numbers of Men 81

V. Patterns for Living Together 108

61148

Lecture I ^

THE UNIQUE MAMMAL

There are living today on the earth well over 5000 different
recognizable kinds of animals that have the habit in common of
getting their young started on their individual life journeys in
a strange way. The mothers elaborate in their own bodies a
fluid that is one of the most perfect all round foods known to
bio-chemistry and physiology. Furthermore these mothers have
their bodies so built as to provide a simple but extremely neat,
handy, and beautiful piece of machinery from which their off-
spring from the moment they begin their free life in the world
can get this almost perfect food with a minimum of effort j and
without the necessity for the exercise on their part of either
intelligence or cunning. It is in fact as easy for them to get this
nourishment as it is for them to beat their hearts or to breathe j
and, alas, sometimes much easier than it is for them to digest
the food after they have got their little paunches full of it.

Because the mothers treat their young in this generous fashion
all these thousands of kinds of animals are called mammals.
Nearly all of them are distinguished from all other animals in
two further ways — one really important biologically and the
other merely odd. The first and important distinction is where
the mother again shines. She provides for the embryonic de-
velopment of her young within the superb physiological pro-
tection of her own body during the long period from the fer-
tilization of her eggs up to the time the offspring are ready to
be born. The machinery of this most perfectly regulated of
incubators is highly complicated — too much so to be gone into

1

2 MAN THE ANIMAL

here — but in essence it amounts to the formation of a new and
important organ every time a baby gets under way. This organ,
the placenta, has for its physiological purpose to make an
elaborate ultra-modern plumbing connection between mother
and baby, of such a sort that after its function of transferring
back and forth the stuffs that life must have and the wastes that
living entails it can be sloughed off by both parties to the pro-
tracted transaction, without any residual harm to the bodily
integrity of either.

The other odd peculiarity of mammals is that, with a few
exceptions, they have hair. In nearly all of them it pretty well
covers the whole body. That this is an oddity rather than a deep
biological necessity is indicated by the fact that it is difficult to
think of any useful purpose that is served by hair that is not
equally or better accomplished by feathers. And if we may judge
by the birds it appears certain that mammals would seem more
beautiful if the evolution of skin appendages had been let rest
with the achievement of plumage.

II

Among the thousands of species of mammals man constitutes
one kind, flatteringly called Homo sapiens. Clarence Darrow
maneuvered William Jennings Bryan into denying this plain
fact some years ago, but the denial was an error that Bryan
shortly regretted. For man definitely is a mammal j and, as
will presently appear, a great part of what he is, and of what
he does, is ineluctably consequent upon that fact.

When Linnaeus laid down the classification of animals that
in its broad essentials has not required alteration since, he put
the mammals at the top of the long ladder that life had climbed
in its evolutionary progression j and at the top of the mammals
and the very topmost tip of the ladder, man. It is a pleasant
thought that this gave him a sort of transcendental allegorical
background for his much later acquired and quaint habit of
flagpole sitting. No man in his more rational moments has ever
seriously questioned the rightness of placing Homo sapens

THE UNIQUE MAMMAL 3

where Linnaeus did in his classification. Nor has anyone doubted
that his closest biological affinities were with the other infra-
human Primates. Nor, considering the important part that
vanity plays in human nature, is it likely that man's pinnacled
position ever will be questioned by himself, even if it were not
the fact that the scientific reasons for classifying him as Linnaeus
did are inherently sound and convincing.

While everyone agrees that man's closest living relatives are
found in the four men-like apes, gorilla, chimpanzee, orang, and
gibbon, there is no such agreement about the precise structure
of his ancestral pedigree. The evidence that he had a perfectly
natural and normal one, and was not specially created to meet
a felt need for university professors and bartenders, is over-
whelming in magnitude and cogency. But exactly what the
individual steps were, or how they came about, is still to be
learned. There are nearly as many theories on the point as
there are serious students of the problem. All of them at
present, however, lack that kind of clear and simple proof which
brings the sort of universal acceptance that is accorded the Law
of Gravitation, for example. Only on one point, and that one a
little vague, can there be said to be general agreement. It is that,
on the weight of the evidence, it is probable that at some remote
period in the past for which no clear paleontological record
has yet been uncovered, man and the other Primates branched
off from what had theretofore been a common ancestral stem.
The doubt is about when, where, and how this branching took
place. Personally I am of the opinion that the conclusions
reached by Dr. Adolph H. Schultz, one of the most distin-
guished and widely experienced students of the problem, are
on the whole most closely in accord with all the known evidence.
These conclusions, in brief, are that the earliest branch to come
off from the common anthropoid stem was the one represented
by the existing Hylobatidae (gibbons and siamangs) j that
shortly after this branch had separated another independent
branch came off the common stem and ultimately developed
man as we now know him j that at a considerable time after this

4 MAN THE ANIMAL

human branch had started on its independent way what was
left of the main stem split in two, one limb eventually producing
the orang-utan as we know it, and the other limb being the com-
bined gorilla-chimpanzee branch, which not long after split
in two, to lead finally to the gorillas and the chimpanzee as they
now exist.

Linnaeus recognized that man was the unique mammal, and
listed six respects in which he could be so regarded. These were
respectively theological, moral, natural, physiological, dietetic,
and pathologic. For the most part these differentials alleged by
Linnaeus to separate man from other mammals are not regarded
now as seriously as they were in a more naively credulous age.
To put forward as generic diagnostic attributes that man is cre-
ated in the image of God and has an immortal soul, or that he
has a rational mind so that he may praise his Creator, strikes us
today as verging upon the metempirical. And to say that man
is physiologically a most perfect and stupendous mechanism is
perhaps all right if one feels moved to that kind of language,
but after all much the same thing might be said of a gorilla, or
a tiger, or an elephant, and hence does not mean a great deal
as a differential characteristic. But if Linnaeus's grandiloquently
pious characterizations of man are now a bit outmoded, his
ringing nosce te if sum is the perfect slogan for a growing science
of Human Biology. For it states as completely as it does con-
cisely the objective of that science.

Nowadays the disposition is to focus attention upon less
grandiose points in respect of which man is different from other
mammals. There are a good many of these, but four are of
very great significance, especially in their implications and con-
sequences. These are:

1. Man's habitually upright posture.

2. His big brain, which is larger both in absolute dimensions
and relative to his body weight than that of any other
animal.

3. His capacity for articulate speech.

4. His longer life span.

THE UNIQUE MAMMAL 5

It will pay us to spend a little time over the first three of
these points. The fourth will be left for special treatment in a
later lecture to be devoted to that topic alone.

While a number of other mammals for a part of the time
either sit, or stand, or even walk upright for short distances,
man alone habitually carries on the business of living in that
posture. All other higher mammals make locomotion the pri-
mary demand upon their fore-limbs. Even the gibbon, which
comes nearest to man in the proportion of the whole life span
spent in the upright position, still depends heavily upon his
fore-limbs as locomotor organs. And the degree or extent of
his assumption of the upright posture but fractionally approaches
man's, though it comes nearer to it than any other mammal's.
The effect of adopting habitually the upright posture and de-
pending solely upon hind legs for getting about was obviously
to free the arms for other activities and uses. With this freedom
came the development of the human hand; in which "we have
the consummation of all perfection as an instrument. This, we
perceive, consists in its power, which is a combination of strength
with variety and extent of motion; we see it in the forms, rela-
tions, and sensibility of the fingers and thumb; in the provisions
for holding, pulling, spinning, weaving, and constructing;
properties which may be found in other animals, but which are
combined to form this more perfect instrument." (Sir Charles
Bell's Fourth Bridgewater Treatise ^ 3d edit. p. 23 1, 1 834.)

Anaxagoras, the intimate friend of Pericles, inspirer of
Euripides, and perhaps teacher of Socrates, was of the opinion
that the intellectual superiority of man over other animals
rested fundamentally on his possession of hands. This view had
a certain recrudescence in Benjamin Franklin's designation of
man as "the toolmaking animal", and finds today a certain de-
gree of real and substantial support in the underlying philosophy
of the behaviorist school of psychology. It was categorically
opposed by Aristotle, who almost uniformly spoke disparagingly
of Anaxagoras, perhaps because he did not understand him too
well. Aristotle turned the case end for end, saying that man had

6 MAN THE ANIMAL

hands given to him because he was the wisest creature j thus
substituting a bit of teleological natural theology for a perfectly
good, if unproven, biological working hypothesis capable of
being tested. In this matter Galen trailed along with Aristotle,
as was his wont.

Whatever may turn out to be the ultimate views on this
somewhat recondite philosophical point, there can be no doubt
that the development of the hand enormously aided man in his
struggle for survival and progress. A remote, but extremely im-
portant, consequence usually overlooked is that the possession
of developed hands, as we know them with all their manifold
capabilities, opened out to man a much greater range of new
and enormously useful methods and techniques of getting a
living than those available to other animals. This is a matter
about which more will be said later.

Physiologically the habitually upright posture is not yet an
unmixed blessing. It is so relatively recent an acquisition in
the evolutionary time scale that all of the necessary structural
and functional adaptations of the basic mammalian type of body
have not yet been completed. An obvious example of this is the
frequency of visceroptosis ("sagging innards" in a homely way
of speaking) and the distressing complications that often follow
in its train. Furthermore the upright posture increases greatly
the demands made upon the circulatory system, as compared
with the situation under the quadrupedal mode of life. Stout
as the circulatory system is there is evidence that the adoption
of the upright posture was followed by an associated increase
in the proportion of the total mortality assignable to that organ
system. But there would seem to be no doubt that the large credit
balance in the general biological bank accruing from the freeing
of the fore-limbs from locomotory duties, and thus making pos-
sible the development of highly specialized hands, a great deal
more than offset the general physiological and pathological
debits.

The greater size and complexity of the human brain in com-
parison with that of any other animal has attracted the atten-

THE UNIQUE MAMMAL 7

tion of all students of evolution. It has generally been regarded
as the most important feature, in a practical point of view,
differentiating man from the other mammals. This is, of course,
because of the association of greater mental capacities and abili-
ties with the larger and more highly organized brain. The dis-
tinguished Dutch anatomist and anthropologist Eugene Dubois,
who was the discoverer and principal student of that extraor-
dinary "missing link" between man and his humbler forebears
called Pithecanthropus erectuSy has for many years laid stress
upon the value of brain size in proportion to body size as a
quantitative index of evolutionary progress. In 1897 he put
forward a formula for what he called the "coefficient of cephali-
zation." This formula stated that for any species of mammal
the coefficient of cephalization K was equal to the brain weight
in grams divided by the body weight in grams raised to the
5/9^^ power. Numerically evaluating this coefficient on the basis
of actual weighings, he first found that the cephalizations of
the gorilla, the chimpanzee, the orang, and the gibbons are all
approximately equivalent and equal to about one-fourth of the
value of the cephalization coefficient for man. The cephalization
coefficients for the tiger, the cat, the buffalo, and the goat proved
again, according to Dubois, to be approximately the same in
each of these forms, and equal to about one-eighth of the value
for man. For rodents like the rat and the mouse the cephaliza-
tion coefficient was much smaller, amounting to only about one-
quarter of that for the carnivores and herbivores just mentioned.
The well-known French student of the brain-weight problem,
Louis Lapicque, and his collaborators came forward in 1905
with evidence from birds confirmatory of the same rule, and in
1913 Dubois claimed to have established it for reptiles and
fishes. So that now he regards it as a law of evolution for
vertebrates in general.

Dubois made an interesting generalization from his numerical
results, to the effect that as one goes up the evolutionary series
it appears that the coefficient of cephalization tends approxi-
mately to increase in a geometrical progression of the term 2 j

8 MAN THE ANIMAL

by doubling or repeated redoubling, in short. He then concluded
that the reason for this progression by doubling of the brain
volume was to be found in "the natural property of (most)
living beings or tissues to grow by bipartition of cells. It is thus
that the number of nerve cells increases and brings about the
progression of brain organization." The most interesting thing
about this progression is its discontinuity — its doubling jumps —
if the results and deductions of Dubois be accepted at their face
value. Brain volume, and inferentially mental capacity, have
not progressed evolutionally to their present pinnacle in man
by gradual travel up a smooth ramp, but rather by climbing a
flight of stairs in which each riser is twice as high as the one
next below it. When we come near to the top of the stairs
Dubois finds, as already mentioned, that there are two degrees
of difference instead of one between the existing anthro-
pomorphous great apes and man in respect of encephalization.
One step in the old staircase is left out. That missing step Dubois
triumphantly assigns to Pithecanthropus ^ whose coefficient of
encephalization he figures out to be "exactly double that of the
anthropomorphous apes, and exactly half the human coefficient."
Insofar then, but only insofar, the Trinil ape-man may be
regarded as the "missing link."

All this makes a fascinatingly interesting story, and whether
or not it be fully accepted at the valuation attached to it by
Dubois, it is based upon long, patient, and, in the best scientific
sense of the word, imaginative research. It almost compels
speculation about a theoretically possible, even though long
distant future. Suppose it to be the case that the evolutionary
process has not yet ended for all eternity with man. And suppose
further that man is able to survive as a species for a sufficiently
long further period so that a gene mutation or alteration occurs
of such sort as to lead the nerve cells of the brain each to make
one more division than is now the case before ceasing to divide
at all. Then, provided this hypothetical mutation did not alter
the dividing behavior of any other cells of the body except
those of the brain, the world would find itself possessed of a

THE UNIQUE MAMMAL 9

species of veritable super-men, with six-pint brains instead of
the present three-pinters that would then seem by comparison
so pitifully small and inadequate.

But we must not pursue this speculation, though nothing
now known of genetics or brain embryology and anatomy can
definitively rule it out as impossible. There is, however, one
solid fact about which there can be no disagreement. It is that
the greater size of brain, with its associated enhanced mental
capacity, has been of enormous practical advantage to man in
his struggle for survival, and in bringing him forward from
the level on which he emerged as a new genus of mammals, in
respect of all those arts, crafts, and techniques of living gen-
erally that are peculiarly and indeed uniquely human. Just as
in the case of upright posture, however, a biological debit was
incurred by this encephalic specialization. The more highly
organized human brain breaks down under the stresses of living
more easily, and leads more often to the death of the whole
organism than is the case with the simpler central nervous
system of the lower vertebrates. While comprehensive and pre-
cisely accurate statistics on the point are not available a rough
approximation suggests that if we take as unity the proportionate
mortality in the reptiles and the birds that can be assigned to
breakdown of the central nervous system from whatever cause,
the corresponding figure for infra-human mammals is about 2.5.
That is to say proportionately two and a half times more
mammals than birds and reptiles die from causes affecting the
nervous system. The corresponding figure for more primitive
human groups is about 18.0. That for the most highly civilized
and culturally most advanced human groups is about 27.5. In
other words it appears that in the evolutionary progress from
reptiles and birds to the most advanced sorts of men the relative
mortality assignable to breakdown of the central nervous system
has been multiplied more than twenty-seven fold. These figures
are not to be regarded as absolutely precise appraisals, but
roughly they do indicate something of the biological price that
man has to pay for his high-toned brain. Also of interest in this

10 MAN THE ANIMAL

same connection is the finding of the recent National Health
Survey carried out by the U. S. Public Health Service. This
survey indicated that of all chronic diseases afflicting the popu-
lation of the United States the category "Nervous and mental
diseases" took first rank In respect of both number of invalids
and number of working days lost because of chronic illness.
These diseases of the central nervous system were found to be
responsible for nearly twice ( 1 .9 times) as many chronic invalids
as heart diseases j three and a half times as many as all forms of
tuberculosis together, 4.4 times as many as hardening of the
arteries and high blood pressure j 7.8 times as many as diabetes j
and almost ten (9.6) times as many as cancer. It would be hard
to find a better illustration of the biological rule that a price Is
always exacted for the benefits that go with evolutionary
specialization. In this same connection it Is also worth noting
that Malzberg, a careful and critical statistical student of the
insane, has recently come to the conclusion that in New York
State at the present time there is occurring a relative increase In
the incidence of mental disease, not very great In amount nor In
his opinion warranting at present too serious eugenic concern,
but still real.

The capacity for articulate sfeechy which Is unique to man, has
plainly been valuable to him biologically. It seems a fair ap-
praisal to say that it may well have been more responsible than
any other single factor in the development of his particular type
of social organization. Indeed the eminent Sanskrit scholar
William Dwight Whitney was quite positive on this point, say-
ing In the first series of his Oriental and Linguistic Studies
(1873, p. 296) that: "The specific moving power to the working
out of speech was not the monkeyish tendency to Imitation, but
the human tendency to sociality." The available evidence seems
to Indicate that In the early stages of his evolution as a distinct
species man was probably not naturally much, if any, more
gregarious and cooperative than are the great cats like the lion
and the tiger at the present time, where such stable sociality as
exists is pretty well confined to the biological family group. The

THE UNIQUE MAMMAL 11

ability to talk things over and by so doing to bring the then very
rugged individualists into a frame of mind for group effort must
have greatly aided in the beginning steps of the emergence of
human social behavior. In the early stages of man's racial acquisi-
tion of the faculty of articulate speech social approval was prob-
ably an important element in speeding up improvement in the
new art. Pillsbury and Meader, in their very useful Psychology
of Language^ regard as an important element in the transfer
of a baby's "gurgles and poppings of the lips" to words, "the
incentive that comes from social approval as the early words are
spoken, the smiles they draw from the admiring members of
the family, and the pleasing way in which they are taken up
and repeated."

It is impossible here, as well as unnecessary for present pur-
poses, to go into further detail regarding the part played by
articulate speech in human evolution. It will suffice to let the
case be summarized in the words of Edward Sapir, a master in
the field: "The truth of the matter is that language is an
essentially perfect means of expression and communication be-
tween every known people. Of all aspects of culture it is a
fair guess that language was the first to receive a highly de-
veloped form and that its essential perfection is a prerequisite
to the development of culture as a whole." And, as the same
author says in another place, society, in the more intimate sense,
is "a highly intricate network of partial or complete under-
standings between the members of organizational units of every
degree of size and complexity, ranging from a pair of lovers
or a family to a league of nations or that ever increasing portion
of humanity which can be reached by the press through all its
transnational ramifications."

There have now been discussed in some detail three of the
most important respects in which man may justly be called the
"unique mammal," namely his habitually upright posture, his
out-size brain, and his faculty of articulate speech. Before leav-
ing this phase of the development of our subject, it should be
emphasized that in all three of these respects the difference

12 MAN THE ANIMAL

between man and the other mammals is at bottom quantitative
in character rather than qualitative. In each respect man is dif-
ferent from his other milk-giving congeners by virtue of being
only "more so," rather than by being completely alien in kind.
Thus most mammals other than man stand up on their hind
legs occasionally and for short periods for one reason or another.
And, conversely, as one of America's most distinguished anthro-
pologists Dr. Ales Hrdlicka has shown in great detail and
wealth of example, human infants not infrequently show a
strong predilection for walking on all fours, indicating that it
was only a little while ago and not yet protoplasmically for-
gotten that this was the regular way of locomotion. All that
man has done evolutionally in this regard is to acquire the
habit of spending more and more of his time upright, with
the important consequences already discussed. Again all mam-
mals have a brain similar in kind to man's, only just not so big
or so rich in nerve cells. Finally all mammals, as well as many
animals lower in the evolutionary scale, have ways of com-
municating with one another and with the group to which they
belong. Our cat Minnie is capable of telling us, in a regrettably
raucous and unmusical voice, that she is hungry and that we
must do something about it at once; and of vocally making it
known to her kittens that they are ranging dangerously far
from base and must rush to cover at once. Man's powers of
communication have merely been perfected beyond those of
his closest zoological relatives to the stage of articulate speech.
So, in sum, it is seen that even in the highest of his biological
achievements man still remains a mammal au fond. However
snobbish about the matter he may, and in fact does, tend to be
there is no escaping from the insistent reality of his family con-
nections. His vain efforts to do so, more particularly under the
subtle stimulation of religion and theology, have resulted only
in inspiring the great and true humanists like Lucian, Rabelais,
Swift, and Voltaire to their highest flights of wit and humor.
It lies beyond the range of my biological competence to say
whether man is formed "in the image of God," but there is

THE UNIQUE MAMMAL 13

no smallest doubt about his being a mammal. And so far from
this being a handicap or detriment, the exact opposite is much
more nearly true. Man's firm biological anchorage to his solid
mammalian mooring is the greatest source of his strength in
the cosmic scheme of things.

Ill

The three peculiarities of man discussed in the preceding
section, though they represent only quantitative differentiations
from the mammalian stem, have had four far-reaching conse-
quences in human behavior, that in turn have led to the
separating of man very far indeed from all other animals.
These we shall now discuss. They are, stated as propositions:

1. Man is a time-binder.

2. Man is an organ-adder.

3. Man is the foremost environment-maker and controller.

4. Man is most diversely adept at getting a living.

Time-bindingy to borrow the happy phraseology of Count
Korzybski, is biologically one of man's most important achieve-
ments, if for no other reason because of the large and always
increasing amount of time that it saves him. For time-binding
is the permanent accumulation of experience and knowledge by
means of the printed record. With the development of written
language, and later the correlative art of printing, man started
the accumulation in perpetuity of his past racial experience.
Furthermore these techniques of preserving and accumulating
experience are in the highest degree precise and exact. Euclid's
exposition of the basic propositions of plane geometry needs no
improvement and has not been bettered. The printed record
preserves it for our use forever. The inherent perfection of
the time-binding techniques leads to the broad biological result
that there is a steady progression, with no backward steps, in
man's power to control and adapt to his needs and uses the
forces and resources of the world in which he lives. Each
generation does not have to discover all over again the ways to
do this.

14 MAN THE ANIMAL

All other animals except man are able to accumulate only
the experience of their own individual life times, so far as
concerns everything except the basic physiological processes that
have become embedded in their protoplasm as instincts and
habits, so-called. This embedding has probably been imple-
mented by a process that m_ay be called "protoplasmic memory,"
as, on the whole, the best choice from the various terms that
have been used to designate it. This process has been particularly
discussed by three important persons, the physiologist Hering,
who was the first professional biologist to develop the concept
in modern times, in a short but valuable essay j the zoologist
Semon who wrote a somewhat too verbose book about it (Die
Mneme ah er halt end es Prinzif im Weeks el des organlschen
Geschehens. Leipzig, 1904) j and Samuel Butler, the author of
Erewhon and of various biological treatises that still probably
deserve more attention from professional biologists than they
have ever received, except from a few. The concept of proto-
plasmic memory is basic in Butler's philosophy of biology. He
brings pretty much everything under its wide explicatory em-
brace, with great skill and imagination. Butler's book Life and
Habit develops the matter in extenso^ but in 1876 he sum-
marized his views in a letter that may be quoted here, both
because of its piquant Butlerian charm and because it offers as
inherently probable an explanation for certain biological phe-
nomena as any that has ever been proposed by anybody. The
extract is quoted from Festing Jones's Samuel Butler ^ Vol. II,
pp. 445-5 (1919):

"1. Actions which we have acquired with difliculty we now
perform almost unconsciously, e.g.^ playing the piano, reading,
writing, walking. As soon as we know how to do a thing ex-
ceedingly well, consciousness in respect of it vanishes. As long
as we know that we know a thing we do not know itj we only
know it when we do not know of our knowledge.

"2. Whatever we do in this way is all one in kind, the dif-
ference is in degree. We play the piano almost unconsciously,
we write more unconsciously, we read very unconsciously, we

THE UNIQUE MAMMAL 15

walk and talk still more unconsciously j our breathing is, to a
certain extent, under our control, our heart's beating is per-
ceivable but not under control, our digestion is unperceivable
and beyond control.

"3. A baby cannot grow itself in the womb unless it knows
how to do it, and to know how to do it, it must have done it
before or it will be contradicting all human experience. Its
unconsciousness is the result of over-knowledge.

"4. It learnt to do it when it did it before j that is, on the
previous occasion when it was an impregnate ovum.

"5. It has attained to unconscious knowledge of how to do it
by doing it a very great number of times in the persons of its
ancestors.

"6. But how about identity? There is no identity of matter
between me as I am now and me as I was when I was an
impregnate ovum, but there may be continuity of existence.
And there may be a modified identity between me as an impreg-
nate ovum and my father and mother as impregnate ova. Let us
consider my ovum as the means adopted by my parents' ova not
for reproducing themselves but for continuing themselves, and
let us see the intermediate lives as a long potato shoot from one
eye to the place where it will grow its next tuber.

"7. Given a single creature capable of reproducing itself
and it must reproduce a creature capable of reproducing itself
and so on ad infmitum,

"Then comes Descent with Modification. Similarity tem-
pered with dissimilarity and dissimilarity tempered with simi-
larity— a contradiction in terms like almost everything else that
is true or useful or indeed intelligible at all. A begets A' which
is A with the additional experience of the prime. A^ begets A^%
which is A with the additional experience of A^ and A^' and so
on to A^'y but you can never eliminate the A.

"8. Let y4" stand for a man. He begins as the primordial cell
splitting himself up for ever, and for ever gaining experience,
always doing as he did before when last he was in the same
position but always with the additional experience gained by

16 MAN THE ANIMAL

his having done it once oftener than when he did it last. First
he will do his tadpoles by rote, so to speak, on his head, from
long practice J then he does his fish trick j then he grows arms
and legs, all unconsciously from the inveteracy of habit till
he comes to doing his man, and this lesson he has not yet
learnt so thoroughly. Some part of it, as the breathing and
oxidization business he is well up to, inasmuch as they form part
of previous roles, but the teeth and hair, the upright position,
the power of speech, though all tolerably familiar, give him
trouble — for he is very stupid, a regular dunce in fact. Then
comes his newer and more complex environment and this
puzzles him — arrests his attention — whereas consciousness
springs into existence, as a spark from a horse's hoof.

"Thus we are all one animal, and reproduction and death are
phases of the ordinary waste and repair which go on in our
bodies daily."

Considered as a theory of inheritance, which was Butler's
main interest in the whole business, all this is not only out of
date, but in fact never was in date. This is not merely because
it got no serious consideration from competent biologists, ex-
cept in a few instances. More generally it is because all theories
of heredity that have ever gained general acceptance, aside from
local national loyalty as in the case of Lamarck's, have been
atomistic doctrines, in which "little balls" or tiny "chemical
packets," in the germ cells are held to be the essential mecha-
nism by which inheritance is caused and controlled. But if we
confine attention to the biology of accumulating racial experi-
ence about physiological matters, such as heart beating and
breathing, the modern gene theory is inherently even funnier
as a rationalized explanation than old Butler's protoplasmic
memory based on unbroken protoplasmic continuity.

But even supposing that Butler's theory of accumulating
racial experience were to be accepted at full face value it is
evident that it would be enormously inferior in precision and
comprehensiveness to written language and the printing press
as devices to achieve the same end. However one views the

THE UNIQUE MAMMAL 17

matter, man's talents as a time-binder not only make him unique
among all other animals, but in itself alone assures that his cul-
ture— his techniques of living — must in the nature of the case
always move forward if they move at all. Only a universal
cataclysm that destroyed all his written records could set him
back on the road he has travelled.

We turn next to the consideration of man as an organ-adder.
It has been the accepted teaching of evolution that man gained
his ascendancy in the organic world because of the superior
development of his brain. Weaker than many other animals,
less swift of foot, a comparatively poor swimmer, and limited
by his meager physical endowments practically to life on the
surface of the earth alone, man is generally thought to have
become the dominant species among living things solely because
of his superior cunning and wisdom. However adequate this
picture may have been in the very earliest stages of his emer-
gence as a new and distinct form of life, the case is different
now. Man is not merely smarter than other forms of life. Today
he is physically the strongest of all known animals, by a vast
amount. He can move from place to place at speeds enormously
greater than those of any other known animal, and do this
either on the surface of the earth, in the air, or in or on the
water. He can see through opaque objects and for great dis-
tances, and can hear a fly's gentle footfall. He can talk to a
friend on the other side of the world without raising his voice.
He can project lethal agents vastly farther than any other
known animal, and kill distant prey, or a predator seeking to
annihilate him.

In short, man has taken an evolutionary step during a rela-
tively short period wholly unparalleled in his prior history.
He has added to the power and strength of his muscles and
bones, and to the delicacy and range of his sense perceptions in
a degree beyond anything that even the wildest imaginations
were ever able to conceive before the event. It is customary to
regard the methods by which all these results are accomplished
as purely mechanical, having nothing to do with biology or life.

18 MAN THE ANIMAL

But consider the matter more carefully. If a man wields an axe
for eight hours a day, week in and week out, he presently adds
certain definite, new, useful structures to the physical equipment
with which he started. These are the calluses which develop at
the main bearing points on his hands. When they are well de-
veloped these calluses are as dead as the axe handle itself. But
they are highly useful to the man. They are useless and mean-
ingless in any other relation. Biologically they are adaptive
structures added to man's previous manual equipment. But so
precisely is a steam shovel. A modern steam shovel is an adap-
tive structure which can be attached to a man's hands. With his
hands strengthened by the addition of this equipment his power
is so increased as to make the Behemoth a "wee, sleekit, cowrin,
tim'rous beastie" by comparison. The man and the steam shovel
together constitute one single organism, partly made of flesh,
partly made of steel, but operating, if it operates at all, as one
single integrated unit.

All useful machines are additions to the adaptive biological
equipment of man as an animal. Some are additions to his motor
powers; others to his sensory. But their fundamental meaning
is always biological. Except as a part of man's biological equip-
ment they have no significance.

To what does this lead us? The thought has been advanced
by not a few persons that the development of machinery is
fer se a menace to mankind; that machines will dominate men.
But why? Machines are only parts of men. They are merely
extensions of, or additions to, his arms, or his legs, or his eyes,
or his ears, or to some other organ system. They are added
organs. And man is the only animal that is an organ-adder, in
any significant degree. This attribute or capacity has been of
great, indeed incalculable, value to him in his struggle for
survival and in his evolutionary progress.

In order that the significance of man^s achievements as an
environment-maker may be adequately appreciated it will be
necessary to digress for a moment to speak briefly of the rela-

THE UNIQUE MAMMAL 19

tionship between organism and environment generally. For the
sake of brevity this discussion may start with the bald and con-
densed proposition that the relationship between any organism
and its environment is particular, continuous, indissoluble, and
reciprocal. It is particular because each individual organism has
its own environment peculiar to itself and not fully shared
with any other organism. Adam Short, six feet three inches tall,
has a definitely different environment at all times and places
than does Hiram Long, who is five feet tall and nearly as broad.
All conceivable differences between individual organisms, and
there is an indefinitely large number of such differences, neces-
sarily entail associated differences in the environment that is
particular to the individual. The relationship is continuous be-
cause at no time while life exists can organism and environment
be separated. It is indissoluble because organisms are dependent
for their very existence upon energy and matter derived from
the environment. Finally the reciprocal characteristic of the
organism-environment relationship arises because each individ-
ual organism is continually altering its environment in some
degree even if only very slightly, and in turn is itself being
altered by the environment. For example in running across a
snow-covered field a rabbit alters the field at least to the extent
of the tracks it leaves; and, conversely, after this simple event
the rabbit itself is a different rabbit from what it was before
or would have been if the field had been, let us say, grass-
instead of snow-covered. This is designedly a very simple, and
in that sense "far-fetched" example of an extremely complex and
important part of biology. What it leads to is the broad principle
that, in varying degrees from species to species, all animals
both choose and make their environments. In other words the
organism-environment relationship is never a completely hap-
hazard or random connection, such as that between pennies and
their environment when say 50 perfect and physically identical
pennies are tossed together. In the latter case the behavior of
the pennies is wholly determined by the action of the environ-

20 MAN THE ANIMAL

ment (gravity, air pressure, etc.) upon them. In the case of the
living organism the environment only partly determines what
it will be under any particular set of circumstances.

Man has carried these characteristics of environment-choosing
and environment-making to vastly greater extents and degrees
than any other animal. So much is this so that although the
difference is in principle only quantitative, as we have seen, it
nevertheless by its magnitude alone puts man in a class by
himself. His prowess in environment-making is primarily the
result of his superior intelligence, which in turn has led to the
development of his arts and sciences. It is sometimes alleged,
and a good deal of evidence is advanced from such sources as
geographical distribution, survival of extreme hardships in
exploration, and the like, that man exhibits the highest degree
of biological adaptability of all animals. In a superficial view
this seems probably true. But in reality the point has never
been adequately tested. For what happens when people habitu-
ally live in the dreadfully harsh environment of the polar
regions, for example, is that by the arrangement of their hous-
ing and clothing and in other ways they make for themselves
an effective environment that in the most essential respects
approximates the environments of temperate or even torrid
zones. The distinguished Arctic explorer Vilhjalmur Stefansson
has given much information on this point from his long ex-
perience with the Eskimos. During the long winter night these
people spend nearly all their time virtually naked in igloos at
temperatures of the order of 80° F. and above. Furthermore
their clothing is so constructed as to be most effectively pro-
tective when they are out of doors. Stefansson has even sug-
gested that the relatively early age at menarche observed among
Eskimo girls is probably connected with the high temperature
of their effective environment. Again the environmental hard-
ships of explorers are now generally recognized to be expressions
only of failure to push out around them as they advance an
adequate quasi-pseudopodial cloak of mellow temperate en-
vironment. How can the comparative grade of man's organic

THE UNIQUE MAMMAL 21

adaptability be justly appraised when he persists in making
himself an environment demanding only a minimum of true
biological adaptation?

In the case of "civilized" man achievements in environment-
making need no emphasis. Manifold examples are everywhere.
He modifies the earth, air, and water of his world to his use.
He alters to his wishes and needs, in greater or less degree, the
plants, animals, and men with whom he makes contact im-
mediately or remotely. The activities comprised within the term
"public health" furnish perhaps the most impressive example.
By his alterations of the environment to this end man has added
something of the order of a quarter to a third of a century to
his average duration of life in a relatively short period of his
history as a species.

I shall stop at this point and continue the discussion of man
as the unique mammal in the next lecture.

hecture II

THE UNIQUE MAMMAL

(Continued)

I

The three unique characteristics of man discussed in the pre-
ceding lecture — upright posture, big brain, and articulate speech
— and their three derivatives — time-binding, organ-adding, and
environment-making — have all combined to make available
to man vastly more diverse ways of getting a living than are
enjoyed by any other organism. In essence any living organism
is a pattern through which must pass continually a stream of
matter and energy if it is to continue to live. If and when this
flow of matter and energy stops for more than a very short
time, life stops too and the pattern that was the individual or-
ganism ceases to exist. So long as this flow continues the fattern
has all the importance that we are accustomed to attach to indi-
viduality. It has also the added importance that derives from
its being the sole repository and guardian of whatever there is
of personal identity. When an individual is born he is given
a name as a symbol of personal identity. As long as he lives he
is thought of as the same identical individual, even though for
some reason or other his name may get changed. But the matter
of which he is composed, his physical and chemical substance, is
constantly changing throughout his life. It is only the pattern
that remains permanently his.

Samuel Butler discusses this matter entertainingly and pene-
tratingly in hije and Hahit^ though in his zeal to bolster his
theory of heredity he gets off in places into a very miry bog of

22

THE UNIQUE MAMMAL 23

quite unsound biology. But up to a point he paints a true pic-
ture of the difficulties that inhere in the concept of personal
identity of a living organism. As he says (pp. 84-5): "Surely
all reasonable people will feel that an infant an hour before
birth, when in the eye of the law he has no existence, and could
not be called a peer for another sixty minutes, though his father
were a peer, and already dead, — surely such an embryo is more
personally identical with the baby into which he develops with-
in an hour's time than the born baby is so with itself (if the
expression may be pardoned), one, twenty, or it may be eighty
years after birth. There is more sameness of matter; there are
fewer differences of any kind perceptible by a third person;
there is more sense of continuity on the part of the person him-
self, and far more of all that goes to make up our sense of same-
ness of personality between an embryo an hour before birth
and the child on being born, than there is between the child
just born and the man of twenty. Yet there is no hesitation
about admitting sameness of personality between these two last.

"On the other hand, if that hazy contradiction in terms, 'per-
sonal identity,' be once allowed to retreat behind the threshold
of the womb, it has eluded us once for all. What is true of one
hour before birth is true of two, and so on till we get back to
the impregnate ovum, which may fairly claim to have been
personally identical with the man of eighty into which it ulti-
mately developed, in spite of the fact that there is no particle
of same matter nor sense of continuity between them, nor recog-
nised community of instinct, nor indeed of anything which goes
to the making up of that which we call identity."

Now keeping up the flow of matter and energy through the
organism means getting a living, in the literal and complete
sense of the words. Nearly all living things other than man get
their livings in one or the other of two ways, or by some com-
bination of them. These two methods are:

A. By preying upon other organisms, plant or animal in na-
ture as the case may be. In general this is the animal way of
getting a living.

24 MAN THE ANIMAL

B. By directly transforming inorganic material into their
own living substance, with or without the aid of energy derived
from sunlight, or from complex chemical processes. This is, in
general the plant way of getting a living. Most animals, in-
cluding man, have no natural talents or facilities for getting
a living this second way.

Now man has added to these two basic methods a great variety
of other ways of getting a living, which however may all be
brought together under a single broad category:

C. By doing things, or making things, that can be traded
with other men for things necessary for living.

It was a momentous day in evolutionary history when this
mode of getting a living was hit upon. Commerce and industry
were then and there engendered. The "economic man" was
born, and also the slave; not to speak of policemen and
politicians.

Biologically the two most important consequences of so
widely expanding the effective ways of getting a living were:
first, that great numbers of persons were individually able to
survive who would not have been capable of doing so by the
old method Aj and, second, that a much greater total popula-
tion could support itself on the earth than had before been the
case. To see how these results came about it will be necessary
to look a little more in detail into the specific techniques by
which mankind has gone about getting its living. The primary
and dominant business of life is getting a living and its modes
have determined the type patterns of culture back through the
whole history of human kind. There have been four such broad
culture types or stages : the hunting type, the pastoral type, the
agricultural type, and the industrial-commercial-service type.

In the pure hunting type of culture mankind lives by direct
and never-ending predacity upon other animals and to a lesser
and more seasonally limited extent upon plants. This mode of
life achieves only a very low degree of what we call economic
security in present day language, and that little at the expense
of a maximum of physical labor. It requires large areas of terri-

THE UNIQUE MAMMAL 25

tory per unit of population. Or conversely expressed this type
of culture will support only very low densities of human popu-
tion. Further it demands a high degree of nomadism, or in
other words a small arnount of domesticity in the sense of fixed
permanent abode. When the supply of game animals of a
region has been depleted by persistent hunting the hunter and
his family are compelled by necessity to move on to new regions.
Finally hunting is a mode of life not conducive to the de-
velopment of social organization beyond the level of the biologi-
cal family. In essence it is a system of individual exploitation of
natural biological resources, with little or no element of con-
servation or economic safeguarding of the future through the
exercise of thrift and the consequent building up of capital re-
serves against a potentially difficult future time.

The fastoral tyfe of culture represents in nearly all respects
an advance beyond the hunting stage. Its philosophy rests funda-
mentally on the idea of domesticating in some degree particular
sorts of animals on which it is the intention to prey, so that the
supply may to that extent be controlled and conserved. Further-
more it separates the plant predation one step away from man
himself by having the domesticated, or partly domesticated,
animals that the humans in this culture stage propose to live off
gather in the plant resources and process them for human use.
The pastoral mode of life achieves a definitely higher degree of
economic security than the hunting, and demands in doing this
a distinctly smaller output of human energy in the form of
physical labor. Like the hunting way of living it requires large
territorial areas and can support only low densities of human
population, though in this respect it again operates, on the
average, at a somewhat higher level than the hunting type. It
requires a considerable degree of nomadism, but not to the
same extent as the hunting stage. Under the pastoral culture
plan the migrations tend to be seasonal and within rather definite
and fixed geographical limits — back and forth between good
grazing territories in short. But there can be nothing like real
permanence of abode. As Gibbon said: "The camp and not the

26 MAN THE ANIMAL

soil is the native country of the genuine Tartar." Little in the
way of sociality is developed, though it goes somewhat farther
in this way than the hunting type. Beginning elements of thrift
and deliberate conservation of resources are a definite and im-
portant part of its plan.

The agricultural way of living represents in all respects an
enormous advance over the two preceding types. Its philosophy
is much more profound. In the first place it fundamentally ex-
ploits directly the chemical resources of the earth as well as the
strictly biological resources. The soil is the farmer's '^country."
The underlying reasoning is as though the primitive farmer
said to himself something like this: "Why not always have
plenty of plant food, and other desirable things that come from
plants, for myself and my animals, by the simple device of sav-
ing seed each year and planting it the next. Then I shall not
have to work so hard to get a living. I can fix myself up a nice
comfortable place to live in and not have to be always packing
up and moving." In putting the case in this way it is not intended
to imply that any great number of actual farmers ever con-
sciously thought thus cogently and consecutively, either in the
dim evolutionary past or now. But however vaguely sensed this
is the philosophy of agriculture. It still remains at bottom, like
its cultural predecessors, biologically a predaceous way of living,
but the predacity is now ordered and controlled. The only hap-
hazard element theoretically left in it is what rests on vagaries
of climate and weather — what man has long been accustomed,
in one form of language or another, to call "acts of God," though
now to some extent improperly so. As the great legal authority
Wharton once {Law of Negligence 557, p. 435, 1878) said:
"Why is a hurricane an act of God, when by our weather-signals
we are able to anticipate hurricanes?"

The advantages of the agricultural way of life over its prede-
cessors are manifold. It achieves much greater economic security
with less physical labor. The total expenditure of human labor
is reduced partly because of the nature of the agricultural proc-
ess itself, and partly because fixation to a definite territorial

THE UNIQUE MAMMAL 27

location makes it possible to use extrahuman sources of power
much more effectively to do necessary work. Its areal require-
ments are smaller, and consequently population and population
density per unit area can increase. It encourages domesticity and
takes away the necessity for nomadism, and in so doing satisfies
the human trait of "stay-at-homeness" that is deeply rooted in
man's mammalian ancestry. The very vast majority of all human
beings live and die near to the spot where they were born. The
1931 census of India showed that of more than 350 million
people enumerated by birth place fewer than one million were
living elsewhere (Wattal, The Population Problem of Indiay
p. 123, 1935). The same thing in principle is undoubtedly also
true of mammals generally. Among them there appears to be
a strong sense of home territory. Eraser Darling {A Herd of
Red Deery 1937) while emphasizing the meagerness of present
knowledge of the subject, and the crying need for Intensive
research, ventures the following Interesting and pertinent gen-
eralizations from his field studies of the red deer in Scotland
(pp. 30, 3 1 ) : "Range, then, is determined physiologically more
than psychologically; territory psychologically as much as, or
more than, physiologically. There are two great classes of terri-
torial animals — hunters and grazers — and this division is of
greater significance to the observer of animal behaviour than in
zoological classification. The hunting pack is comparable with
a capitalist organization having a fair measure of state control.
Territory is guarded jealously and fighting follows intrusion.
Size of territory is governed largely by the density of numbers
of the animals hunted. The limited degree of gregariousness and
co-operation is for the purpose of hunting rather than being
familial In origin. In fact, many hunting animals show no
sociality beyond the single family. The hunting animal which
Invades another's territory goes in fear of his own kind and is
ready to run or fight. The grazing herd, on the other hand,
shows a state comparable with the City of the Laws of Plato:
Communallty and disciplined orderliness which need but little
discipline. Environmental conditions being equal, territories are

28 MAN THE ANIMAL

bounded by choice and not by jealousy. If circumstances call
for it, another group's territory may be occupied j but this occu-
pation is tolerated, and the groups may combine in face of the
common need. The herd is in itself a bulwark against the hunter
and predator."

Finally it is to be noted that agriculture promotes the de-
velopment of sociality to a far greater extent than the more
primitive culture types. Its territorial fixation in itself tends to
hold together by community of interest larger groups than the
immediate biological family, first through progressively more
and more remote collateral relatives. At a later stage exogamy
brings the necessity for social relations with similar "foreign"
groups.

As has already been pointed out the most momentous cul-
tural epoch in man's history began when he became aware that
he was able to get a living by a wide variety of techniques
different in kind from the three that have been discussed, and
embarked in a big way upon the industrial-commercial-servke
mode of life. It automatically and at once appeared to, and in
a comparative sense in fact did, achieve a degree of economic
security never before dreamed of. If a living could be got by
making or doing things for people, a job was plainly going to
be at hand so long as there were people about. The physical labor
necessary to get this security was again plainly on the whole
a mere fraction of that required under the old techniques.
Organ-adding helped to guarantee this. Territorial require-
ments became minimal. In fact the nature of the technique itself
demanded higher and ever higher densities of population per
unit of area, leading rapidly to the development of ever larger
and larger cities until the average density of population over the
whole land surface of the globe, including all the bad and un-
inhabitable land in the computation, has now come to be about
41 persons per square mile. The necessity for nomadism dis-
appeared, to be replaced by almost obligatory domesticity and
fixed habitation. Not merely was it conducive to social organi-
zation but it absolutely required and led to a most extraordinarily

THE UNIQUE MAMMAL 29

complicated and intricate form of sociality j such, in fact, that no
individual or group could possibly avoid social relations. Pre-
dacity gave way to service j and altruism, not much heard of be-
fore, burgeoned to replace the protoplasmically grounded
selfishness of the biological struggle for existence. At least these
were the plain theoretical implications of this way of living. It
needs no pedantic elaboration of the matter to convey the sug-
gestion that in some respects the actual course of events has not
always closely followed the theoretical path. But these di-
vergences may best be left at this point for more ample discussion
later. The main point now is that the industrial-commercial-
service way of life has been, up to the present time, the culmina-
tion of the long process of setting man apart from all other ani-
mals as the unique mammal that we have so cursorily reviewed.
It is hoped that in this review one leading fact has been made
plain. It is that in the evolution of ways of getting a living the
trend of the progression has all along the route been from harder
to easier methods, insofar as concerns the expenditure of physical
(muscular) energy. Reflection suggests that it would perhaps
not be an unfair statement to say that biologically the develop-
ment of easier ways to get a living is on the whole the greatest
achievement of the human intellect. Looked at from an evolu-
tionary point of view the result appears to be congruent with
the general rule of organic nature that all living things tend to
get their livings with the minimum of effort possible under their
circumstances of life. Remembering that plants are just as much
and as truly living organisms as animals, it is an obvious and
somewhat overwhelming statistical fact that the vast majority of
living individuals on the earth are sessile — rooted to one par-
ticular geographical spot and spending none of their energies on
getting about. Incidentally it is worthy of note that it is among
these fixed and rooted plants that by far the longest individual
life spans are found. Various species of trees outlive many times
over any known multicellular animal. Evaluated by the im-
personal biological yardstick of survival the unbustling fixed
way of life would seem to be a good one. Later on in these

30 MAN THE ANIMAL

lectures occasion will be taken to follow further the implications
of this point.

IV

So far the discussion has been of those characteristics that set
man apart as unique among the mammals. The treatment of
the case has been positive and affirmative in character. Now
it will be well to emphasize the conclusions reached by looking
briefly at the negative side — that is by showing in outline that a
great many of man's characteristics and behavior are essentially
identical with the characteristics and behavior of the other
mammals — the lower classes of animals from which he stemmed.
It will then be completely clear that while man is the unique
mammal, he is so in only a comparatively few respects, but
those extremely important ones.

In the first place the general plan and pattern of man's
anatomical structure is mammalian. The correspondence is un-
cannily close and manifold, as every budding biologist learns
the first time he dissects a cat and compares his findings with the
pictures in Gray's Human Anatomy. As J. S. Prichard, one of
the founders of modern anthropology, said in his Natural
History oj Man ( 1 843) more than a quarter of a century before
Charles Darwin's Descent of Man appeared: "In all the prin-
ciples of his internal structure, in the composition and function of
its parts, man is but an animal. . . . The points of resemblance
are innumerable j they extend to the most recondite arrange-
ments of that mechanism which maintains instrumentally the
physical life of the body, which brings forward its early de-
velopment and admits, after a given period, its decay, and by
means of which is prepared a succession of similar beings des-
tined to perpetuate the race."

What is true of man's anatomy in this respect is also true of
his physiology. His heart, his lungs, his kidneys, and his
endocrine organs function in the same way as the corresponding
organs in his mammalian relatives. In a broad view and that is
the only one that limitations of time allow to be taken here, the

THE UNIQUE MAMMAL 31

convincing evidence that this is so is found in the history of the
science of physiology itself. For what that history shows is that
the overwhelmingly greatest part of our knowledge of human
physiology has been initiated from experiments made on infra-
human mammals. In every medical school today the funda-
mentals of physiology are demonstrated to the students from
the bodies of dogs. And the information so gained is found to be
completely reliable and trustworthy in the practice of the art and
science of medicine when applied in the relief of human
suffering.

If the essentials of man's physiology are identical with those
of mammalian physiology in general, it is reasonably to be ex-
pected that much of his behavior will be found upon analysis
to be like that of other mammals in similar or equivalent situa-
tions. This is in fact so. A host of examples might be given in
proof. Books could be, and have been, written to this end. But
again taking a broad view, the prime significance of the fact that
a large part of human behavior is just animal behavior is per-
haps best seen in the way this fact has come to be the very
foundation stone of the most advanced modern psychiatric
thinking and action in the treatment and prevention of mental
disease, under the influence of Freud and with the rise of psy-
chobiology. The adequate recognition of the community between
man and the lower animals over great ranges of their psychology
and behavior, and the practical implementation of this recogni-
tion to therapeutic uses, are relatively recent developments. But
the idea itself is at least as old as Aristotle. For it is implicit in the
central thesis of his Psychology ^ which was that life and
mentality were to be regarded as identical terms.

G. Stanley Hall in 1920 (Preface to Freud^s General Intro-
duction to Psychanalysis^ drew an interesting comparison be-
tween Wundt and Freud. Until the appearance of the latter
upon the scientific scene Wundt had been for a long time the
dominant world figure in psychology. There is perhaps no better
way to get a realization, that strikes home with almost shocking
force, of the profound change that has come over all thinking

32 MAN THE ANIMAL

about psychology and behavior, than to examine the contrast
between Wundt's outlooks and attitudes towards his subject and
those that prevail generally now. To be sure this change is
not wholly attributable to Freud's influence, but a large part of
it directly or indirectly is. As Hall said, Wundt had "little use
for the unconscious or the abnormal, and for the most part he
. . . lived and wrought in a pre-evolutionary age and always and
everywhere underestimated the genetic standpoint. ... It is
rather precisely just the topics that Wundt neglected that Freud
makes his chief corner stones, viz., the unconscious, the ab-
normal, sex, and affectivity generally, with many genetic, espe-
cially ontogenetic, but also phylogenetic factors. The Wundtian
influence has been great in the past, while Freud has a great
present and a yet greater future." As events turned out this last
statement was an extraordinarily good brand of professional
prophecy.

Modern psychobiology rests firmly upon an evolutionary,
phylogenetic base. Indeed it would become largely devoid of
philosophical meaning or sense if that base were shorn away
from under it. This is apparent from the formulation of the
attitudes and objectives of psychobiology in relation to psy-
chiatry set forth by the distinguished leader in the field. Dr.
Adolf Meyer {Contributions Dedicated to Dr. Adolf Meyery
etc., edited by S. Katzenelbogen, 1938): "We [have] come
to find ourselves in harmony with the concept of the individual
as obtained by individuation and organization, as a biological
entity with vegetative osmotic functions; next also with motor
functions and, further, with segregation of motor and sensory
functions, which, however, were found to have culminated in
the total-action of the individual presenting symbolization proc-
esses and thereby 'more or less consciousness'; that is to say,
performance studied as a unitary problem first (such as the
fertilized egg-cell), and then secondary subdivisions and differ-
entiations in the process of growth and assimilation and metabo-
lism; these secondary subdivisions might not be only the
subdivisions of what we cultivate in anatomy and physiology, but
subdivisions that have their own working principles, those de-

. THE UNIQUE MAMMAL 33

rived from the new and specific unity the living person. These
working principles in the personality function must no doubt be
brought into harmony with what we know of the principles of
the sciences of physics and chemistry but also with the sciences
of growth and the sciences of organisms. We have to realize that
the study of the organismal total-function, the function that
hangs together by means of symbolization and consciousness,
will have to follow its specific path, according to the relations and
facts found, and that is the path which we found in the biogra-
phy, which we found in the study of the various directions of
functions, the activities, the intellectual functions, the motor
functions proper, the action functions and the affective functions,
and altogether the Sense,' that which we find only and always
as organismal functions. There we find ourselves with what
human wisdom and sagacity has long worked with, as we say, by
intuition, i.e., by using the immediately available facts and
emergents, which ultimately we have to bring into harmony
also with facts and relations arrived at through other channels
and directions and relations."

Human "organismal total-function" spoken of in this quota-
tion just read is an evolutionary emergent, genetically directly
descended from, and in large part still identical with, infra-
human animal "organismal total-function." Unless this fact is
constantly in mind human behavior cannot be sensibly inter-
preted. A great part of what you and I do every day we do
in the way we do because it is a part of the entail of the mam-
malian pattern and substance of which we are made.

It would be difficult to find a more unpedantic (and insofar
praiseworthy) way of making clear something of the range and
nature of the deeply embedded ^mammalian bases of human
behavior than is afforded by Alice Crowell Hoffman's little
disquisition which may now be quoted, by permission, from the
September 1938 issue of Your Life.

What You Can Learn From Your Dog

To keep clean.
To love children.

34 MAN THE ANIMAL

To keep your place.
To chase away flies.
To size up an enemy.
To drink plenty of water.
To be faithful unto death.
To be a dependable friend.
To take plenty of exercise.
To express pleasure when favored.
To speak up when you want anything.
To stay where it's warm in winter and cool in summer.
To guard faithfully the interests of those who care
for you.

This list could obviously be almost indefinitely extended to
include not only items common to human and animal behavior
in relation to alimentary and excretory functions, sex and re-
production, but also a great deal of what is often naively re-
garded as "higher" sorts of behavior. Every young man and
woman is pleased to think that they have made novel dis-
coveries peculiar and perhaps even "sacred" to themselves in
the technique of the art of making love. This is, alas, only a
delusion, albeit a nearly universal one. If a sort of super-tele-
vision-dictaphone apparatus were available for an objective sta-
tistical investigation of the matter it would be found that in
their amatory behavior the Whitechapel costermonger and
his lady say and do pretty much about the same things as the
dainty denizens of Mayfair. This is because human courtship
behavior stems from deep mammalian roots. The proof of this
cannot be undertaken in a public lecture, but must be left for
the seminar and laboratory. But no one of an observant and
philosophic trend of mind, who was brought up on a farm, will
require pedantic documentation on the point.

Dogs, like humans, do "express pleasure when favored," as
every dog lover knows. Dogs, however, have very feeble powers
for the discrimination of motives behind the "favors" vouchsafed
them J or for understanding clearly the consequences foreseen

THE UNIQUE MAMMAL 35

by the grantor of the "favors" as likely to follow. It is interesting
to note that men are sometimes not very diflFerent from dogs in
their behavior in these respects. This was made evident to the
observant human biologist when five billion dollars of the
public money was quite legally distributed where it would do
the most good in a recent election campaign. Neither unctuous
asseverations of nobility of motive, nor indignant denials by the
persons responsible that they were buying votes, nor the serene
unawareness of the recipients of the favors that their votes were
being bought, made any smallest alteration of the realistic fact
that the distribution of the funds was so managed that it did do
a stupendous amount of political "good."

In his vanity man prides himself on being a rational animal.
But really only a small fraction of his behavior is rational. The
rest is just mammalian, or of still lower evolutionary order.

As everyone knows there are a great many kinds or varieties
of men. There are white, black, yellow, and red kinds, to con-
sider only the very superficial matter of skin pigmentation.
There are also many other readily distinguishable kinds where
the features that make it easy to tell them apart have to do with
more fundamental matters. Yet strangely enough the genus
homo includes but one species, though it has many varieties.
Among other forms of life than man it is the rule, to which there
are but relatively few exceptions, that if two individuals really
belong to different species they are infertile inter se. That is, if
they mate together no offspring will result, though in all other
respects they may be extremely, even minutely, alike. The
decisive evidence that man, even with his wide and striking
varietal differences in structure, is properly placed in a single
species is found in the fact that all known kinds of human beings
are not only fertile inter se but produce fertile offspring, when
they breed together. The political philosophy temporarily in
vogue in Germany takes the view that Jews are different in kind
from Aryans (a blessed word of very dubious biological mean-

26 MAN THE ANIMAL

ing, if any). That philosophy also contends that the Jews really,
on a just view, ought properly to be classified with infra-human
primates rather than as men. Not a few professional Southerners
of the ancien regime have held similar views about Negroes. But
the indubitable if sometimes uncomfortable fact remains that
Aryans and Jews, or whites and Negroes, he or she as the case
may be, are exuberantly capable of producing racially mixed
babies by the quite normal and usual technique appropriate to
such matters.

This universal fertility amongst mankind is a phenomenon
of extreme importance in human biology. In the beginning of
man's evolutionary emergence as a new form of life it was pre-
sumably of some help in the struggle for survival. But with the
very limited powers of getting about that he then had the sta-
tistical and social consequences could not have been very great.
By the time man had subdued the horse and the camel to his
uses, however, and had learned that rafts and boats made it
possible for him to "walk on the water," what must have con-
siderably astonished him was the discovery that pretty much
wherever he went desirable girls were to be found, and that
nature could be depended on to take its course there just as at
home.

One of the greatest consequences of the process of organ-
adding that came with the development of the arts and sciences,
and the consequent control and use of natural forces, was an
enormously increased facility and speed of transportation and
communication, a trend that we have not seen the end of yet.
As the shrewdest writer on politics since Machiavelli says:
"During the lifetime of many of us the world has shrivelled
and puckered like a child's balloon slowly deflating, so that now
we find ourselves cheek-by-jowl with peoples and regions that
fifty years ago were regarded as half mythical. And not only
do we see strange faces at close quarters, but we are beginning
to have confidence that some day we may be able to read the
hearts that belong to them."

In a world "shrivelled" by the ease and rapidity of transporta-
tion there inevitably and automatically are created more op-

THE UNIQUE MAMMAL 37

portunities for people to mate together who under earlier condi-
tions never had any such chance. Such opportunities are always
taken advantage of. No degree of strangeness of people to each
other, dissimilarity or supposed ugliness of form or features, or
habit or custom represses completely, or even significantly, the
gratification of the sex appetite. Contact of races or peoples
whenever and wherever it happens means sexual congress across
whatever varietal differences there may be between them. With
charming naivete an unsophisticated young lad who kept a diary
of his experiences when on the gold rush to the Klondike in
1898 (W. R. Curtin, Yukon Voyage, 1938, p. 154) made a
profound biological observation when he wrote: "I see and
hear of so many men who will marry any kind of woman when
women are scarce j not bums either. So-called refined, educated
gentlemen, even college professors, the best we have will do
the same. If a man can live with a smelly Indian squaw, any
kind of white woman is too good for him." Presumably only
inexperience led this young man to fail to recognize that some-
thing other than mere statistics of "scarcity" was involved in the
picture that so shocked him.

If all races and varieties of mankind are fertile among them-,
selves, as is the fact, it follows that increased facility of transport
and travel will result, and is resulting, in the steady breeding
out of the differences that have hitherto marked the varieties of
men. This process is going on at the present time at an ever
accelerating rate. The "swamping effects of inter-crossing," in
the phrase of the old Darwinists, is being exemplified by man
on a world-wide scale. Men get about easily and freely nowa-
days. Because they do, humanity is being slowly but surely bred
to a dead level of mediocrity, using, this term in a strictly techni-
cal statistical sense rather than one of disparagement. In genetic
terminology there is being brought about, at an ever accelerating
pace, a more and more uniform, horizontal, or random distri-
bution among mankind of the genes that hitherto have main-
tained racial or varietal differentiations, because of their original
segregation in separate groups of people.

For lack of the right kind of data it is impossible to measure

38 MAN THE ANIMAL

precisely the rate at which this process is occurring. But an in-
teresting local indication about the matter is seen in the fact that
in 1933, of the 1,763,351 white babies born alive in the United
States to parents of known birthplace, 160,665 or over 9 per
cent, were produced by mothers who were born in different
countries from those in which the fathers had been born. Now
difference in country of birth does not necessarily or universally
connote difference in race or variety, but in the great majority
of cases it does mean that the two parents represented considera-
ble differences in genetic as well as social backgrounds. If in the
computation we consider only specifically named parental coun-
tries of birth, the percentage rises to 10.1. So that, even in 1933
in this country where immigration has for some years been
greatly restricted by law, something of the order of a tenth of
the white births each year, as a minimum, are contributions to the
levelling process of random redistribution of genes. The figures
are for the whole of continental United States and therefore
include those parts of the deep South where "foreigners" have
even yet penetrated but little as compared with the heavily
urbanized and industrialized northern and eastern sections of
the country. But, in any case, the precise figure is of no great
moment. The important thing is that in one of the larger coun-
tries of the world the process of amalgamation of human group
differences by breeding goes on steadily year by year to a sig-
nificant degree.

The social consequences of this process are highly important,
and bound to be increasingly so the longer it is continued. Con-
sider war as a single example. As has been elsewhere pointed
out (Pearl, Studies in Humi.an Biology y 1924, pp. 542-3): "In
general, why men deliberately plan wars is because they are
different biologically, in structure, habits, mental outlook,
thought, or other ways, and wish to preserve intact their differ-
entiations. The more truly conscious they become of these group
differences, the more likely they are to fight as groups. As soon
as they attain the first glimmerings of such consciousness they are
apt to see, or to think they see, something in the behavior of their

THE UNIQUE MAMMAL 39

neighbors which threatens the maintenance of that which begins
to mark them as a nationality. It is the business of their national
leaders to be on the lookout for such things. They may merely
fancy that they detect some danger to the maintenance of even
their present status in something that a neighboring nation does.
It may be a very intangible thing, and the interpretation of its
significance may be entirely wrong, but that does not matter. The
explanation of why men fight is very simple. It is, first, because
their kind of people is different from other kinds j second, be-
cause they want to make sure that their kind shall either main-
tain or improve its status in the world j and that which is thought
to ensure most certainly the maintenance and extension of group
differences in the widest sense is relative politico-social domina-
tion by the group j and third, because of a general physiological
law that certain emotions tend to lead to action.'*'^

Quite plainly the more the differences between peoples are
bred out by universal intercrossing the more difficult it will be
to stir up wars. Biological internationalism supplements and aids
political and social internationalism. In the far-off end all man-
kind will presumably be a rather uniform lot; all looking,
thinking, and acting pretty much the same way, like sheep. Just
in proportion as biological differences between peoples diminish
so will the frequency of wars diminish. But the diminution
seems likely to be at a fearfully slow rate; it will be a long
time yet before the last war is fought. And a low cynic might
suggest that even war, horrid and stupid as it is, would perhaps
be preferable to that deadly uniformity among men towards
which we are slowly but surely breeding our way.

VI.

In considering the consequences of the universal fertility
between the varieties of the human species emphasis has been put
upon the initial group differences between these varieties, and
their gradual diminution and probable eventual complete ob-
literation as the result of ever more widespread interbreeding.
Let us now give some consideration to the differences between

40 MAN THE ANIMAL

individual human beings. It is one of the most obvious truisms
of biology that no two living individuals are exactly alike in
any respect, whether of form, or function, or chemical constitu-
tion. We know a great deal about these differences between
individual men. An enormous amount of effort in the aggregate
has gone into the measuring of them. The whole science of
physical anthropology is made up of such efforts and their
results. A great part of present-day psychology is turned in the
same direction. What broad generalizations have resulted from
these efforts?

There are three such generalizations that it seems important to
discuss. The first is that many more men differ from each other
by small amounts in respect of any characteristic whatsoever
than differ by large amounts. This is a universal law of variation
in the organic world and an expression of its inherent stability.
The distribution of individual differences tends to cluster about
a center of variation, which is regarded as the typical condition
or norm for that character. Average, run-of-mine individuals
are much more frequent than outsize freaks in whatever respect
they may be observed. This first generalization about individual
variation is really no more than a simple description of how
the world of living things is organized. It has inherently no
occult meaning, and in fact baffles any inquiry as to why it
happens to be so, quite as completely as does the fact that bodies
attract each other in proportion to their respective masses. It
also illustrates the fact that such concepts about natural phe-
nomena as "normal," "typical" or "truth" itself are merely the
expressions of majority opinions so widely concurrent and
congruous as to be practically universal. To illustrate: in a
world so organized that the differences between men in stature
were so distributed as to yield a U-shaped curve instead of in
a cocked-hat curve, as they are in fact, "norrnal" or "typical"
men would be either very short men or very tall men. In such
a world the freak would be the man of average height. The only
reason why in our world men of about average height are "typi-
cal" and "normal" is that there are so many more of them that

THE UNIQUE MAMMAL 41

they constitute an overwhelming majority of the vote when
the "normality" or "type" issue is up for consideration. There is
no absolute or transcendental normality or type. This is a point
well to remember when we get into the more complicated realms
of human biology such as sociality, political behavior, and the
like. The second generalization about human variation is that
the differences in respect of various separate characteristics of
the individual are statistically correlated in greater or smaller
degree, so that, for example, if a man has extra long arms he is
also likely to have extra long legs. This phenomenon of corre-
lation is an expression of the integration that is so important a
feature of the organism in contrast to the inorganic, and that
makes the living organism something more than and different
from the simple sum of its component parts.

The third generalization is that the total range of variation
that exists relative to any characteristic and species stakes out
the limits of viability, or survival, relative to that characteristic in
the whole frame of reference that constitutes the pattern of that
particular form of life. Here we enter upon somewhat new
territory, and illustration and example will be required. Every-
one knows that while the pulse rate per minute varies from
individual to individual, and from time to time in the same indi-
vidual, it does so within quite narrow limits. Furthermore every-
one knows that if the individual's life is to continue the rate of
heart beat cannot transcend these limits. In the state of normal
health and well-being these limits are roughly from some-
where around 50 beats per minute to 90 odd beats per minute. If
under the influence of disease or injury the heart rate goes out
much or long beyond these limits, the individual goes out too,
for good and all. So then a rule can be stated about variation in
human pulse rate that no living human being ever has a pulse
rate more than m times greater than the pulse rate of any other
human being. When a numerical value has been assigned to m
we shall have a limit of viability of the human organism in
respect of individual variation in this characteristic, rate of
heart beat. By taking into account a sufficient number of obser-

42 MAN THE ANIMAL

vations of pulse rates on different people an approximate
numerical value can be assigned to m close enough to satisfy
all practical purposes. And so similarly for other characters, until
in the end one could plot out the whole pattern of the extent of
biologically permissible individual variation consistent with
viability and continued survival, for a great range of character-
istics, structural, physiological, mental, behavioral, and so on.
When this has been done we shall have a sort of map of the
organization territory within which man does his living, and,
by and large, must do it.

Now because of the vast amount of scattered but carefully
collected information regarding the variation of man that exists
in the literature of anthropology, anatomy, physiology, psy-
chology, etc. it is possible to construct such a map. For a number
of years I have been engaged in so doing, as opportunity offered.
Though far from finished the results obtained are of some sug-
gestive interest. In order to present briefly here some idea of
their nature six broad categories of human characteristics have
been chosen, and a relative mean value of m for each category
computed. The categories are as follows:

I. Size and shafe dimensions. These include linear measure-
ments of bodily characters, such as stature, arm length, etc., and
indices measuring shape, such as the cephalic index, and the
like. In this first category there are included over 200 separate
series of measurements, involving all told many thousands of
individual measurements. In general this category shows the
narrowest limits of variation of any so far studied. The absolute
weighted mean value of m for the whole category is 1.153.
The physical interpretation of this figure is that, as an average
of the whole category, the linear and shape dimensions of the
largest and queerest formed adult human beings are only about
1.2 times as great as the corresponding dimensions of the small-
est observed human beings. It must be again emphasized that
this is an average for many different dimensions of the sort
named, and for various races and kinds of people.

II. Physiological dimensions. This category includes such

THE UNIQUE MAMMAL 43

characteristics as pulse rate, body temperature, various bio-
chemical characteristics of the blood, etc. In a broad way this
category corresponds roughly to Claude Bernard's concept of
the "internal environment."

III. Weights. This category includes such characteristics as
the weight of the body as a whole, of its separate organs, etc.
In a general way this category, as compared with the first one
discussed, includes the factor of individual variation in alimenta-
tion— eating habits and their bodily consequences.

Table 1

Relative Variability of Normal Adult Human Beings

Relative Weighted
. Character Categ-ory Mean Value of m

I. Size and shape dimensions 1.00

II. Physiological dimensions 1.78

III. Weights (alimentation factor) 3.37

IV. Motor and sensory performance 9.27
v. Judgment 47.42

VI. Behavior 135.52

IV. Motor and sensory performance. This category includes
such characteristics as speed of running, visual and auditory
acuity, marksmanship, etc.

V. Judgment. Psychological performance in relatively simple
tests involving primarily the faculty of judgment.

VI. Behavior. This category includes measurements of indi-
vidual variation in habits and behavior relative to such things
as smoking, use of alcoholic beverages, frequency of coitus, etc.

In Table 1 are set down the relative weighted mean values of
m for each of the six broad categories of characters that have
been described, the value of w for category I being taken as
1.00. It is to be understood that these values are at present only
tentative, and subject to revision as the investigation here re-
ported for the first time proceeds further.

The figures of this little table are shown graphically in Fig. 1 .

The first three categories include only what may be regarded
as the lower attributes and faculties of man — just anatomical
and physiological things that he has in common with the beasts.

44

MAN THE ANIMAL

The last two categories deal only with what are regarded as
higher faculties, peculiar to man and not shared with lower
forms of life. The fourth category (motor and sensory per-
formance) falls in between the other two sets, in common

In

Behavioa
= 135.52

/^£LAT/\/£ txT£/vr Or//(/Af/l/^ l^/^/AT/O/^

Fig. 1. Relative mean weighted values of m for six broad categories of human
characteristics. (For explanation of what yn means see text.)

every-day interpretation and in biological fact, but in variability
lies much nearer the lower than the higher group.

It is evident that the extent of variation or differences between
human beings is much greater in respect of the attributes and
faculties of the sort included in categories V and VI, than in re-
spect of those in categories I, II, and III. Insofar as these figures
may be trusted as approximations, it appears that men and
women differ from each other in their behavior more than a

THE UNIQUE MAMMAL 45

hundred times more than they do in their bodily build and
general physical make up. In simple judgments they appear to
be nearly 50 times more variable from individual to individual
than in size and shape.

This wide variation among men in behavior, judgment and
such-like things furnishes the primary reason why human living
in this world today is so interesting, so exciting and at one and
the same time both so pleasant and so irritating. If we were all
as alike in our behavior as we are in our bodily build this would
be a dull world indeed. Boredom would not only be justified
but inescapable. As things are now the differences between
individuals stimulate them all to fuller and richer living, day
by day. Just because differences are irritating they are also stimu-
lating. Right now Mr. John L. Lewis and his C.I.O. irritate
profoundly a great many people. But can any sensible person
doubt that out of his activities is coming a searching reconsidera-
tion of the whole question of the relations of labor and capital?
Or that the very ones who hate him most heartily are being
driven to give their best thought to this matter?

The wide-ranging variation among human beings in their
behavior and mental faculties is not, however, universally ac-
claimed as a benison. On the contrary there is abroad in the
world today, and rather rapidly spreading, a viewpoint that
has for its primary objective to reduce this variability as much
as possible. It aims to accomplish this result speedily, without
waiting for the slow results of interbreeding. It proposes so to
regulate and regiment human beings that they will all come to
think and act as nearly alike as possible. We are told by those
of this view that discipline is inherently a good thing — good for
soul and body. We are further told that if all men only will
act and think alike, and as ordered to think and act by some-
body who alleges, like papa, that ^^he knows best what is good
for little boys and girls," they will collectively be able to accom-
plish much more for the common welfare than if each goes his
own way, guided only by his own entirely inadequate capacities.
We are further told that all who do not subscribe heartily to this

46 MAN THE ANIMAL

doctrine are merely dumb fools, who confuse abstractions,
myths, and symbols with reality, an^ are therefore incapable of
managing their own affairs, but really should, for purposes of
government and the common welfare, be regarded as inmates
of a great insane asylum and treated accordingly by "wise" and
"humane" persons who know what is best for them. Oddly
enough this kind of doctrine is separately rationalized by dif-
ferent groups of folk by the application of one or another of
utterly and fundamentally opposite political theories, such as
communism, fascism, and New Deal humanitarianism, so-called.
Each protagonist argues that only by sternly reducing the range
of human variation in behavior and thought can the ultimate
blessings of his curative eye-wash be achieved.

In a later lecture in this series we shall try to see whether a
better way of life cannot be found than any such scheme of
turning man, the unique mammal, into man, the contented cow!

Leciure III

HUMAN LONGEVITY

In the first of these lectures it was pointed out that one of the
important characteristics that set man apart as the unique mam-
mal was his great individual longevity — greater than that of
any other mammal. It was promised that this characteristic
would be given special discussion in due course. The present
lecture aims to redeem that promise. To do this we must first
justify the categorical statement that man has in fact the longest
life span of any mammal. This is quite easy to do, because there
is but one contender against him for the position of supremacy
in longevity. That is the elephant. There has long prevailed a
popular belief that the elephant is fabulously long-lived. This
is only a myth, however, quite unsupported by quantitative rec-
ords. On the contrary all the available evidence agrees on two
points: first, that elephants under domestication, about which
India furnishes long and extensive experience, live on the av-
erage longer than in the wild state j and second, that few individ-
uals tame or wild ever live more than 50 years, and for those
few reliable evidence is lacking that any ever achieves more
than about eighty years of life as an outside maximum. The
case is different with man, as we shall now see.

The available evidence indicates that during the last twenty-
four hours something upwards of a sixth of a million fresh new
human beings have appeared for the first time upon this earth as
a whole. Each of these babies that starts today on the journey
through time called the life span will endeavor, with all its
might and main, to make that journey last just as long as pos-

47

48 MAN THE ANIMAL

sible. For the will to live is the most deeply rooted and per-
sistent of the biological characteristics of protoplasm organized
into individuals. At the beginning of each persons's life this
urge to survival is wholly unconscious, just a part of living
like digestion or respiration j later on this underlying proto-
plasmic will to live, the vital momentum, will be supplemented
in the individual by a conscious effort for longevity. The great
part of today's babies who manage to survive until they are
somewhere in the twenties, will then begin to think a little about
what they should do to preserve their health so that they may
keep on living longer. Virtually all of them who live until they
are seventy years of age or upwards, will think about little else
from that time on. For it is an odd but profoundly true generali-
zation of human biology that the longer a human being has
lived, the more anxious and personally concerned he is, by and
large, to keep on living still longer.

II

The duration of the journey through life that so many
young hopefuls have started upon today will vary greatly
amongst them. Some of the lot will end it tomorrow, so incom-
plete is their vital resource and so fragile their design for living.
Others, a very few others, of the lot will be living a hundred
years from now.

The pattern of these varying life journeys, and the changes
in that pattern in quite recent years, are matters of considerable
interest and worth looking into on their own account as well
as to give us a solider ground for the further discussion of human
longevity. The "order of dying" of a cohort of individuals all
born at the same time is given with great accuracy by a device
known as the life table, that combines mathematics and biology
in a happy and useful mating. For purposes of the present dis-
cussion a certain function called the "survivorship" for two life
tables has been put in a graphic form, on the supposition that
the life journey of which we have been speaking consists in
climbing a long and huge ladder. The first of the two life tables

HUMAN LONGEVITY

49

chosen for this treatment is based on the mortality experience of
1 929-3 1 inclusive, and is one of the latest comprehensive Ameri-
can life tables. The second table to be depicted is based upon
the mortality experience of the state of Massachusetts in the
year 1890. In both cases we shall deal with the order of dying
of white males only. What will be shown in Figure 2 is the

_^runt/ o/c/ya/'fer *f'//o n^/// Aai/e
reacAee/ Aif ycjy V iop of i/ie ladder

2P cente/tan'om

>*'/// Av# ioo/c
tyonc/er/i/^ j/ears

0/7fi/£,37/ny/ii\\de /»/? at SO

ad do

f?a ii*v /i/Ms o/'Mejda^/rrl

, S2. /70h^/// 6e />erfi °^ ^^ \

\ /fSoud /la/f-M^oy foJAe fgr^ ftp -top of/Ae
iodaferAerf at SO dui 7-iSJZarestitt

yft -^O tAere <»-/// de S/. 63 S.
a ^/tt/e. u^eay/e/', ^ut /?ot /77u.cA .

//ere at JO years o^ ase SS.S44
Mt^/t^ st^/t t>e c//f?7t>/rif.

/Utmost as mo/ii/C3S,0S9) M^/// 6e present o/id
^«ti/np rvac/y to yote7?ere

SO, 973 oi^ t/te/?? H^/tt ffet to tt>e

/'/rst /O-year /-u/Tff Aere.

Suppose 700,000 >yAte iabi/ 6oj/s to
start Aere at tAe Sottom toc7ay.

//ere one tt^t /e/K-
at y /OZ

drtacAedJOO

/1/rte<yercreit>

Only /SZ-fJ\i</ere/e/totSO

/fere at t/fe dottorn.

THE LADDER OF LIFE

IG. 2. The ladder of life as it is shaped now (on the evidence of 1929-31) and as it was in 1890,
forty-eight years ago, (For further explanation see text.)

50 MAN THE ANIMAL

shape and dimensions of the Ladders of Life which the respec-
tive cohorts of white boy babies — that of 1930 and that of 1890
— may be imagined as climbing.

The construction of the Ladders is as follows: the total length
(or height) of each ladder is the total sfan of life, which is
about the same in each case — a little over 100 years. The rungs
of the ladder are in each case set ten years of age apart, so that
the bottom rung of each is at 10 years of age, the second rung
at 20 years, and so on. The length of the rungs — the width or
spread of the ladder — is, at each rung, proportional to the
numbers of persons in the cohort who live long enough to get
a foothold on that rung. Naturally both ladders are drawn to
the same scale in the picture. In both cases 100,000 just-born
white male babies are supposed to start together climbing the
ladder. In the case of the 1929-31 Ladder there has been placed
opposite each rung a calendar year date. This is meant to suggest
that it will be a Ladder of Life much like the one here depicted
that the white American boy babies born today will climb. This
is not an entirely wild bit of prophecy, because past experience
indicates that the ladder they will ascend will almost certainly
actually be as good as or better than this one, because it is not
likely that medical and public health progress will abruptly stop
tonight. It is progress in these two fields in the recent past —
within the lives of most of us here tonight — that in large part
has wrought the 1929-31 Ladder of Life into the shape we
have seen.

It is at once evident that the two Ladders, less than half a
century apart in time, are quite different in shape. The one for
1930 has an air of broad substantiality — a solid structure that
holds a lot of people. The 1890 one stands on the same base,
but after the lowest rung is passed it becomes a rather narrow,
gangling thing, with much less of an air of solid stability j re-
sembling strikingly the sort of ladder built for fruit picking,
rather than the broad and heavy firemen's ladders on which
human lives depend. At the fifty-year rung the 1890 Ladder of
Life accommodated fewer than half the persons who started

HUMAN LONGEVITY 51

the climb, while the 1930 Ladder at the same point will hold
almost three-quarters of the starters.

Ill

In these pictures we see graphically how the prospects for
the duration of the journey of life have been altered in the last
fifty years or so, and for the better. The improvement has been
great, and much credit is due to the medical and public health
professions for the part they have played in bringing it about.
But the pictures of the Ladders do not make it entirely clear
just how and wherein the improvement has been made. They
give rather a broad general impression of the whole effect. In
order to apprehend more clearly a very important, and often
overlooked, point about this average improvement in the dura-
tion of the individual's life resort must be had to some other pic-
tures, shown in Figure 3.

These are pictures of Life Ladders too, but of only their upper
parts. Suppose we consider what happened subsequently to
10,000 white males who got to the forty-year rung of the
1890 Ladder in comparison with 10,000 who will get to the
same rung of the 1930 Ladder j and then suppose we make the
same comparison between 10,000 who got to the 70-year rung
of the 1890 Ladder and an equal number at the same position
on the 1930 Ladder.

It is at once evident from the figure that the duration of the
life journey after age 40 for those who have attained that age is,
on the average, only slightly longer now than it was in 1890.
According to the 1929-31 mortality experience 2.9 per cent
of all those (males) reaching forty lived to reach ninety years
of age. But the 1890 experience shows that 2.7 percent, or
almost as many relatively, did the same then. The gain in the
half century for the forty-year old boys is wholly insignificant
in any practical point of view.

The figure further shows that those who attain the age of
70 now actually do not do so well relatively, on the average,
in the way of further survival to still higher ages as did the

52

MAN THE ANIMAL

stalwarts of 1890. At that time six hundred out of every 10,000
white males alive at age seventy lived on to ninety or more.
Now, on the basis of the 1929-31 experience, only 563 manage

this feat.

So it becomes plain that the important achievements in alter-

i90atf-u«ye90

SS3 ai/—^9e90

SO0aii-^g»90

/?^^-jr/

§UI^VIVAL AT THE HIGHER ADULT AGE^

/S90

I

Fig 3 The number of survivors at the later ages from an equal number startmg at age 40 and
at age 70, as shown by the U. S. Life Table (exclusive of Texas and South Dakota) of 1929-31,

and the Massachusetts Life Table of 1890 White males.

ing the shape of the Ladder of Life in the last fifty years, have
been mainly in regard to the lower rungs. And it is chiefly
the lowest, or ten-year rung that has been improved. In 1890
only 72 per cent of the boy babies starting got a foothold on
that 10-year rungj now 91 per cent do. This is splendid and
must certainly be warmly approved of by every small boy. But
there is extremely little in it to bring cheer to the man at forty
who would like to buy an annuity and look forward to gloating
over the issuing insurance company as a nonagenarian. ^ i

In the common way of thinking longevity really means liv-

HUMAN LONGEVITY 53

ing past eighty years, and great human longevity means being
a nonagenarian or centenarian. Progress in medicine and im-
provement in the public health have done little or nothing
about enabling the individual to achieve such a goal, as the cold
statistical facts about the order of human dying make abundantly
clear. The s-pan of human life has not been lengthened, and there
is no present prospect that it soon will be. The average duration
of life is all that has been altered, and that has been accomplished
chiefly by giving more babies a fairer start in life's journey than
they used to have. Because more of them get by the early and
very diflicult hurdles, absolutely more of them survive at later
ages. But the terms of the bet that any individual man aged
seventy today can safely say that he will be alive at ninety ap-
pear to be not quite so good as they were fifty years ago.

IV

Why is it that some individuals alive at any given age will
live thereafter longer than others? In principle the duration of
life of any individual is the net resultant of the interplay between
his own innate biological make-up and the forces acting upon it,
favorable or unfavorable, external and internal. This is a com-
plete and sufficiently logical statement of the case, but not so im-
mediately useful as might be wished for the purpose of dis-
appointing eager morticians.

One of the most often quoted things that Oliver Wendell
Holmes ever said was that if one is setting out to achieve "three
score years and twenty," the first thing to be done, "some years
before birth, is to advertise for a couple of parents both belong-
ing to long-lived families." "Especially," said he, "let the
mother come of a race in which octogenarians and nonagenarians
are very common phenomena." When this statement was made
its only foundation was the general impression of a wise physi-
cian who had spent his own life in a region where octogenarians
and nonagenarians were common phenomena. To what extent or
degree has this impression been supported by exact, quantita-
tive investigation?

As the first and simplest approach to the question let us

54

MAN THE ANIMAL

consider briefly the analysis of the pedigrees of persons who have
actually achieved great longevity. For many years we have
been collecting data about persons actually living at ages of
ninety years and above. The collection now includes more than

I ® —

I

^

<^

n

©0© 0

1 2

IZ

®9(^

12 3

Fig. 4. Pedigree of individual having- highest observed TIAL

2000 such persons, for whom the personal and family records
may be accepted as reliable and trustworthy, after having been
thoroughly and critically checked. Many more cases than this
have gone through our hands, but have been rejected for scien-
tific study because they did not meet the standards of proof
that were set up.

HUMAN LONGEVITY 55

In 1934 my daughter and I published a rather extensive and
detailed analysis of 365 of these cases of proven extreme lon-
gevity. For each of these cases the ages at death of the six im-
mediate ancestors (two parents and four grandparents) were
known and recorded, as well as a great many other things about
the person and the ancestors. As an example, the pedigree of
one of these highly longevous persons is shown in Figure 4.

In this pedigree the person under discussion (the propositus)
is indicated by a solid sex sign. Figures within the circles of the
sex signs indicate the ages at death in years, except where there
is an L above the age figure, which means that the person was
living at the time of record, and at the indicated age in years.

At the top of the chart the mysterious word TIAL is merely
an abbreviation for "total immediate ancestral longevity,"
and is used to designate the sum of the ages at death of the
parents and grandparents. Thus in the present case 104 + 98 +
106 + 93 + 97 + 101 = 599 years. It is safe to say that few
human beings have ever had an authentic TIAL number higher
than this.

But how much lower are the TIALS of ordinary people,
just "run-of-mine" folk who do not themselves live, on the
average, longer than the average of the general population?
To get an approximate answer to this question, and to have a
group to compare with the highly longevous group of non-
agenarians and centenarians we assembled, entirely at random
so far as concerned their own ages, a group of 136 living persons
all six of whose immediate ancestors (parents and grandparents)
were dead at the time of observation, and for each of whom
the age at death was known and recorded. This seems as fair
a group for comparing TIALs with the longevous group as it
is humanly possible to get. This comparison group had an av-
erage living age of 48.75 years, and contained 29 persons over
60 at the time of observation, 6 over 70, and 1 over 80. The
average age of the group was almost 1 6 years higher than that
of the living white population of the United States in 1930.

How does the ancestral longevity of this group of ordinary

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6

HUMAN LONGEVITY 51

folk compare with that of the elite group of extraordinary
long-livers, the nonagenarians and centenarians? Figure 5 gives
the answer in graphic form.

From this diagram it is seen that, on the average, each single
immediate ancestor, father, mother, grandfather, or grand-
mother, of the extremely longevous persons of panel A on the
left side was longer-lived than the corresponding ancestor of
the ordinary persons of panel B on the right side. Thus the
fathers of the longevous died at an average age of 72.4 years.
This was 12.3 years older, or over 20 per cent, than the average
age of the fathers of the panel B folk at the right end of the
chart. The central panel A — B, gives the differences, in abso-
lute numbers of years (upper figures in each sex sign) and as
percentages of the panel B means, for each category of the six
immediate ancestors.

From this chart two results indubitably emerge regarding
the influence of heredity upon longevity, namely:

First: People who achieve extreme longevity have immediate
ancestors (parents and grandparents) who are, on the average,
definitely longer-lived than the corresponding ancestors of the
general run of the population. This is true without exception
for each particular category of immediate ancestors.

Second: This hereditary influence promoting longevity is be-
tween two and three times as great relatively for parents as
it is for grandparents, so far as the results of this investigation
indicate.

It appears, then, that old Dr. Holmes was sound in his
advice to select long-lived parents, and particularly long-lived
mothers.

Let us now go a little deeper into the matter, by proceeding
to examine more specifically how each of the parents of the
extremely longevous persons was bred relative to longevity, as
compared with the parents of the general run of folk. For the
purposes of this inquiry let us regard an individual who dies
under fifty years of age as short-lived j one who dies between
fifty and sixty-nine years as average or mediocre in life dura-

58

MAN THE ANIMAL

tlon, and one who dies at seventy or over as long lived. These
ranges in general agree fairly with common-sense opinion and
usage.

Figure 6 shows the percentages of the fathers and mothers re-
spectively that had (a) both of then parents long-lived (shown
by the solid black portion of each bar) \ (b) one parent long-
lived and the other mediocre or short-lived (shown by the cross-

/^Th^Ef^s or

P£Of>l.£

0£A'£j9y^ LL Y

/WAD

7//£ /ioA/G£VOUS

P£OPL£
(F£/V£/?^LL y

//or/ZE/^s or

6%

^^^^f^^^l

Z7%

Sor// /^^£/vrs
/.or/e-Liyao

0/V£ P^/=(£A/r

A^£-/r/^£^ P^/?£A/r

/.0/Ye~L/^£0

Fig. 6. The percentage distributions, relative to the nature of the parental matings

producing them, of the fathers and of the mothers of (a) an extremely longevous

group (nonagenarians and centenarians), and (b) a defined

sample of people generally

hatched portion of each bar) ; and (c) neither of their parents
long-lived (shown by the white portion of each bar).

The picture presented is precise and striking. The non-
agenarians and centenarians were produced by parents who were
themselves bred out of wholly longevous parentage in more
than half of all the cases observed — a markedly higher propor-
tion than that shown by the parents of the general population
sample. At the other end of the genetic scale the opposite is true.
Fewer than half as many proportionally of the nonagenarians

HUMAN LONGEVITY

59

and centenarians as of persons generally were produced by par-
ents who themselves had no longevous parentage whatever. It
seems clear beyond question of doubt that breeding counted

S35

c/y/hy unc/er* S
years o/'offe.

A7ear?'(2^en'///ei//?7e o^ aye

Fig. 7. Expectation of life in years (mean-after-lifetime) at ages 20, 40, 60, and

80, of fathers of children dying (a) under 5 years of age (solid bars) and

(b) 80 and over years of age (cross-hatched bars)

mightily in the production of these nonagenarians and centen-
arians.

Let us now turn to another method of approach, and a wholly
different material, to get still another view of the importance
of inheritance in the matter of longevity. Suppose one were to

60 MAN THE ANIMAL

go out and collect entirely at random every single case possible
to find of children dying before they were five years old —
extremely short-lived human beings in fact, who were unable
to get far in the pleasant business of living either because they
were inherently bad biological eggs literally or figuratively, or
because they never had a fair chance to live on account of a bad
environment associated with parental poverty or ignorance or
vice. Now suppose further that we followed the fathers of these
poor creatures along through their whole lives and set down
in the record their ages at death when they (the fathers) finally
died. It would then be possible to construct a life table for
the category of Fathers of Persons Dying under 5 Years of Age.
Having done all this, suppose we next did precisely the same
thing for a group of fathers of persons who did not die until
they were eighty years old or more — in other words, a group
of old gaffers with demonstrated great powers of living, which
powers may conceivably have arisen from their innately superior
biological make-up, or from great good luck combined with
good sense in their choice of victuals and drink, or from always
wearing their rubbers when it rained, and so on through the en-
tire list of precepts and superstitions thought to promote lon-
gevity. When the data had been collected and the computations
made we should then be in possession of a life table for the
category of Fathers of Persons Dying at 80 and Over Years of
Age.

How will these two life tables compare with each other? The
next figure. Figure 7, shows the answer so far as concerns the
expectation of life (or average-after-lifetime) at four selected
ages twenty, forty, sixty, and eighty years.

It is at once evident that, so far as concerns the present ma-
terial involving well over a hundred thousand life years ex-
posure to risk, the long-lived children had fathers who were
much longer-lived than the fathers of short-lived children.

Corresponding life tables for mothers tell the same sort of
story.

The relative excess in life duration of the parents of long-

HUMAN LONGEVITY

61

lived as compared with short-lived children is very considerable.
Thus the mean-after-lifetime of fathers of children dying (or
living) at ages of 80 and over is about IS per cent greater at age

Sons o/^/a//?ers
c/t/Zn^ (//7c/erS0\
JO '7^ inc/usfVe
o/7(/(S0 a/7c/a^er\
years ofo^e.

Afe(7n'afier-//^//r??e ai age

Fig. 8. Expectation of life in years (mean-after-lifetime) at ages 0 (birth), 20,

40, 60, and 80 years, of the sons of fathers dying- (a) under 50 years of age

(solid bars) 3 (b) between 50 and 79 years of age (double cross-hatched bars) j

and (c) 80 and over years of age (single cross-hatched bars)

sixty than the mean-after-lifetime at the same age of fathers
of children dying under five.

What now of the situation turned the other way about? How
will the respective life tables compare if we construct them for

62 MAN THE ANIMAL

the children of short-lived, moderately long-lived, and very
long-lived parents? This we have done for sons as a class, with
the results shown in Figure 8.

Plainly the results of these life tables for sons confirm the
conclusions derived from those for fathers that have just been
examined. As we pass upwards through the three broad classes
of paternal longevity the expectation of life of the sons at all
ages steadily rises. The expectation of life of the sons of short-
lived fathers is less than that of the sons of moderately longev-
ous fathers, and still less than that of the sons of extremely long-
lived fathers. Thus at age sixty the sons of very long-lived
fathers (eighty and over) have a further average expectation
of life nearly 40 per cent greater than that of sons whose fathers
died before age fifty.

It seems unnecessary to present further evidence to demon-
strate the great significance of genetic factors in determining
individual differences in the length of human life. The inherited
biological constitution of each individual human being — his or
her genetically determined inherent viability — is beyond ques-
tion one of the major determiners of the probable length of that
persons's life. It is not, however, the sole or absolute determiner.
Obviously anyone can behave in such a way that his or her
genetic birthright in longevity is prevented from coming to
its full expression. Prematurely taking one's own life by the
suicide route is perhaps the most nearly perfect example. On the
other hand the general effect of public health and sanitary
measures is to create and promote such conditions of living as
will permit the greatest possible number of people to bring as
nearly as possible to complete realization and expression the in-
herent vitality with which they have been genetically endowed.
In the changing shapes of the Ladder of Life shown earlier
it has been seen how great the progress has been in this respect
for the earlier years, and how little for the later years of the
life span. This suggests, in the light of the evidence regarding
the inheritance factors in longevity, two conclusions that may
be of considerable significance. The first is that there exist broad

HUMAN LONGEVITY 63

classes of human beings diflPerentiated from each other in their
innate endowments in respect of inherent viability, one class
being short and the other being long of this important quality.
The second suggested conclusion is that improving the environ-
mental circumstances of living can do, and has done, a great deal
more for the first class than for the second in the way of in-
creased longevity. It appears probable that there is now, and
always has been in past ages, a class of human beings by nature
so abundantly endowed in the matter of viability that they
have always, as a statistical group, so nearly realized their
innate potential viability regardless of environmental circum-
stances as to be not significantly affected in average duration of
life by any general improvement of those circumstances.

Detailed study of the life histories of extremely longevous
persons, such as has been possible with our collection of such
records, strongly suggests that nonagenarians and centenarians
are biologically differentiated from the general run of mankind
in just the manner postulated for the second biological class
just described. As a group nonagenaria'ns and centenarians have
definitely not led protected lives in specially favorable environ-
mental circumstances; nor have they had better medical advice
or care than the generality of menj nor, finally, have they con-
ducted their lives more hygienically than others, according to
the rules and precepts generally regarded as conducive to long
life. On the contrary they have just lived, but lived a much
longer time than most.

V

So far the discussion has been almost entirely of the innate,
constitutional elements concerned in the determination of indi-
vidual life duration. It is now time that some attention be de-
voted to the environmental aspects of the picture. Here is where
the quest for personal longevity finds its greatest interest. While
in an academic or philosophical point of view it is doubtless de-
sirable to know as much as possible about the hereditary and
constitutional factors influencing life duration, still these are

64 MAN THE ANIMAL

after all not matters about which much can be done in the way
of promoting personal longevity. What Everyman really wants
is to be able to do something effective right here and now about
a matter of such transcendent personal concern. He would like

HISTOIRE

DES PERSONNES

Q^UI ONT VECU

PLUSIEURS SIECLES,

ET QUI ONT RAJEUNI:

AVEC LE SECRET

DU RAJEUNlSSEMfiNTu

Tire d'Amauld de ViUeneuve,

Et des Regies pour fe confervercnrantd,
5c pour parvcmr a un grand age.

Far Mr, DE LQNGEVILLE HARCOVET.

A PARIS,

Chez la Veuve Carpentier, 5c Lau*

RENT LE COMTE. I716.
A^EC AttRObATlON ET VRIVLlEGE,

Se vend A BRUXELLES,

Chez Jean Leonard, Libraire ^

Imprimcur rue dc u Cour.

Fig. 9. Facsimile of the title page of Harcouet's Histoire

HUMAN LONGEVITY

65

to be authoritatively told how he should conduct his life so to
live long. Still better he would like to be provided with some
pleasant pill or potion guaranteed to keep him going until he
reaches ninety at least, without any bother about what he eats or

Fig. 10. Facsimile of the frontispiece of Harcouet's Histoire, depicting- the Foun-
tain of Youth. Original size of engraved area, 110 X 66 mm.

66 • MAN THE ANIMAL

drinks in the meantime, or whether he bundles up well when
he goes out in the cold. Best of all he would like to be supplied
with some of the authentic juice that flows from the Fountain
of Perpetual Youth.

Since mankind started making literary records of his thoughts
and aspirations the search for that elusive Spring has been
earnestly prosecuted. Many people have figured out just what
it would look like when it was found. One of the most charming
and delightful of its many portrayals serves as the frontispiece
of a rather rare book that is one of the gems of an extensive
collection of tracts and treatises dealing with longevity down
through the ages. The title page of this book and the frontis-
piece depicting the Fountain of Perpetual Youth are shown
in facsimile in Figs. 9 and 10.

One notes the triumphant and smug satisfaction with which
his conductor is telling the weary and sceptical old physician
in the lower left foreground, who may be Aesculapius himself:
"There, you doubting old fuddy-duddy, I said it was here, and
here it is! See for yourself! " In the right foreground is evident
the almost obscene eagerness of the old boys just arrived to
guzzle the precious fluid gushing from the Fountain, while the
bloated saurian leers up at them and gets his share. In the distant
background we get a glimpse of the Garden in which so much
of humanity as was there remained perpetually youthful, until
the lady unfortunately committed a technical error. The fauna
of the environs of the Fountain is characteristically reptilian. It
will also be noted that an elephant is emerging from the trees in
the background. This is to round out the lesson of the picture as
a whole j because, of all mammals except man, the elephant is
the longest lived. The Reptilia of course have always been noted
for longevity. The banner borne by the two Rocs at the top of the
picture is an anchronism, plainly put in as a sop to conservative
respectability. For if we really had access to the Fountain of
Perpetual Youth who would worry about health?

Unfortunately it has proved impossible to get a supply of
water from the Fountain of Youth to distribute on this occasion.

HUMAN LONGEVITY 67

Lacking this the best that can be done is to discuss some of the
environmental factors that have been thought to be, or in fact
are, importantly concerned in the achievement of longevity.
Only those will be chosen for discussion about which there
exists definite scientific evidence, pertinent to the point at
issue.

Of all such factors the use of alcoholic beverages has probably
been most discussed. The problem of the effect of such usage
upon longevity has excited violent and unreasoning prejudice
on the part of large numbers of people. They contend that
alcohol always and everywhere shortens the lives of its users.
There is much evidence, experimental, statistical, and actuarial
that this is not a universally valid generalization. This evidence
does not make the slightest impression upon those who believe,
that is to say have faithy that the generalization is valid. So an
imfasse results. So far as I am aware there has been constructed
only once a set of life tables for classes of persons homogenous
in respect of their habits relative to alcoholic indulgence, and
based upon critically adequate and pertinent data collected at
first hand. Those life tables lead to the general conclusion
graphically depicted in Figure 11.

That conclusion is that moderate drinking is not significantly
associated with any alteration of life duration, either for better
or worse, when compared with total abstention from alcohol,
while heavy drinking is definitely associated with a serious
diminution in the length of life.

These results have been accepted by some, and rejected by
other equally sincere, equally honest, and intelligent groups of
people, who however differ widely in their emotions and senti-
ments regarding the use of alcohol by man as a beverage. Noth-
ing further can be done about the case. Presumably each one
of the present audience is already a component of one or the
other of these two groups.

Let us turn next to the use of tobacco and longevity. This
usage is probably, along with that of alcohol, one of the most
widespread amongst humanity relative to substances or materials

68

MAN THE ANIMAL

that are not, in themselves, necessary to the maintenance of life
as is food. Is the smoking of tobacco associated statistically with
any impairment of the normal expectation of life, or with an
improvement of it, or is there no measurable association one
way or the other? This question, too, has excited controversy,

loojaco

dA(XV

iS ^ 45 SH iS (a 6S 70 75 60 £}

A^ in Years

90 95 100

Fig. 11. The number of surviving- males out of 100,000 starting together at age

30, in three drinking categories: (a) abstainers (solid line), (b) moderate

drinkers (dash line), and (c) heavy drinkers (dot line)

though not so violent as that over alcohol. It is the intention to
present now a small part of the results of a statistical investiga-
tion of this problem. The data were collected at first hand. Their
accuracy as to the relative degree of habitual usage of tobacco,
and as to the ages of the living at risk, and of the dead at
death can be guaranteed. The figures to be presented deal only
with white males, and with the usage of tobacco by smoking.

HUMAN LONGEVITY

69

The material falls into three categories, as follows: non-users
of tobacco, of whom there were 2094; moderate smokers y of
whom there were 2814; and heavy smokers y of whom there

Fig.

so 60 70 SO

yfG£ /A/ Yky^/fS

12. The survivorship lines of life tables for white males falling" into three

categories relative to the usage of tobacco. A. Non-users (solid line) ; B. Moderate
smokers (dash line) ; C. Heavy smokers (dot line) .

were 1905. In other words, the results presented here are based
upon the observation of 6813 men in total. Naturally these men
were an unselected lot except as to their tobacco habits. That
is to say they were taken at random, and then all sorted into
categories relative to tobacco usage. For each of the three cate-

70

MAN THE ANIMAL

gories of tobacco usage complete life tables from age thirty
on to the end of the life span have been constructed. Figure 1 2
shows the survivorship lines.

The net result is obvious. In this group of nearly 7000 men
the smoking of tobacco was associated definitely with an impair-

f50

-5

Indoor Occupations
Difference in the Mortality Rates at
ages in heavy occupations (Quintile H)
and light occupations (Quintile l).
(Deaths fronr) accidents and occupational
hazards deducted).

15 20 Z5 20 35 40 45 60 55 60 65 70 75 60

Age

Fig. 13. Difference between (a) indoor occupations involving the greatest amount
of physical exertion (quintile V) and (b) indoor occupations involving the least
amount of physical exertion (quintile I), in respect of age specific mortality rates.
The line is crossed from age 65 on to indicate that its true position is uncertain
at advanced ages, because of the meagerness of the data available.

ment of life duration, and the amount or degree of this impair-
ment increased as the habitual amount of smoking increased.
The contrast between the life tables relative to the implied
eflFects upon longevity of moderate smoking, on the one hand,
and the moderate use of alcoholic beverages, on the other hand,
is very striking. The moderate smokers are definitely shorter
lived than the total abstainers from tobacco j the moderate drink-
ers are not significantly worse or better off in respect of Ion-

HUMAN LONGEVITY 71

gevity than the total abstainers from alcohol. Heavy indulgence
in either tobacco or alcohol is associated with a very poor life
table, but the life table for heavy smokers is definitely worse
than that for heavy drinkers up to about age sixty. Thereafter
to the end of the life span the heavy smokers do a relatively

15 20 25 30 35 40 45 50 65 60 65 70 75 W

Age

Fig. 14. Same as Fig. 13, except that it deals with outdoor occupations

better job of surviving than the heavy drinkers. But neither
group has anything to boast about in the matter of longevity.

The third environmental problem to be discussed may be
put in this way: Is hard physical labor associated with a short-
ened life.? The answer to this question for indoor occupations
is shown graphically in Figure 13.

The results indicate that there is a direct and definite correla-
tion between the magnitude of the age specific death rates
from age forty to forty-five on, and the average expenditure of
physical energy in occupation, afler accidental deaths and deaths
directly resulting from the hazards of each of the several occu-

72 MAN THE ANIMAL

pations have been deducted. This relation is of the sort that
associates high mortality with hard physical labor. The relation-
ship prevails whether the labor is performed chiefly indoors or
chiefly outdoors, Figure 14.

It is not primarily to be attributed to the general environ-
mental factors connoted by social class distinctions, which are
themselves correlated with average energy expenditure in occu-
pation. Before age forty is attained, it makes no difference in
the rate of mortality whether the occupation involves light or
heavy physical labor. After roughly age forty to forty-five it
appears that the average duration of human life is shortened,
by definite amounts, in proportion as physically heavy labor is
performed.

The literature of longevity is full of advice, recipes, and pre-
cepts for the attainment of long life. These precepts touch upon
nearly every conceivable aspect of personal physiology and
hygiene. Yet it is an odd fact that careful study of our collec-
tion of life records of nonagenarians and centenarians leads, as
one of the broadest generalizations it is possible to make from
them, to the conclusion that these 2000 and more persons ex-
hibited substantially the same range and degree of variation
relative to these various items of personal hygiene as is found
amongst people in general. Some were light eaters, others on
the gluttonous sidej some used tobacco, others didn't; some
drank heavily, others moderately, while still others were tee-
totalers; some slept a lot, others didn't; some had been in
robust health all their lives, others had been ailing a great part
of the time; and so on. In only one outstanding respect besides
great longevity did the group markedly differ from the gen-
erality of mankind, on the whole. That is in the fact that a vast
majority of these extremely longevous folk were of a placid
temperament, not given to worry. They had taken life at an
even, unhurried pace. In this respect this human material agrees
with and confirms a generalization that has emerged from ex-
perimental studies on life duration. It is that the length of life
is generally in inverse frofortion to the rate of living. The more

HUMAN LONGEVITY 73

rapid the pace of living is, the shorter the time that life endures.
This relationship has been shown to exist for a variety of forms,
including plants, various lower animals, insects, and men. It is
a relation that is obviously in some degree within the power
of individual, personal control.

The study of longevity is not ended. In the view of the biolo-
gist it has only just got well under way. A great deal more
will be learned, and just possibly we may find out how to
lengthen significantly and at will the span of human life, in-
stead of merely increasing its average duration. But if and
when this happens there will immediately become evident some
of the difiiculties inherent in another set of problems of social
biology, different in kind from those of longevity fer se. Let
us now give some consideration to these other problems.

VI

Up to this point the discussion has been of the total duration
of life of man considered as a whole. But in actual fact the life
span of man from birth to death falls into three natural bio-
logical divisions. The fact itself that there Is such a natural di-
vision, and the nature of the parts themselves into which the
total span divides itself, are phenomena of great significance,
and particularly so in relation to their social consequences, both
superficial and fundamental. These three divisions of the life
span may be conveniently and justly labelled as (I) the m-
fantile fre-refroductive feriody extending from birth up to fif-
teen years of age, as a round figure j (II) the reproductive
feriody extending from fifteen years up to about fifty years;
and (III) the senescent fost-refroductive feriody extending
from about 50 years to the end of the life span. The first two
of these periods are obviously of first-rate importance in the
business of human living, philosophically viewed. For if the
vital fires are to be kept perpetually alight the young must be
nurtured until they are ready to reproduce. Also the reproducers
must keep busy about their breeding as long as they retain the
capacity, if the continuance of the race is to be safely assured.

74 MAN THE ANIMAL

Persistent living during these two periods has not only bio-
logical justification but is absolutely imperative in a statistical
sense. For the third period there is no evident biological justifi-
cation. The preservation in life of individuals who have passed
the reproductive period is a biological and social luxury that
we encourage only because civilized man is the kind of animal
that likes this particular form of vital extravagance. Among
lower animals and primitive men the existence of a post-
reproductive period of life is only, and strictly, on a permissive
basis rather than one of solicitous promotion as with us. Bio-
logically life after reproduction is ended is only the expression
of a sort of vital momentum. The machinery of living having
got well going in infancy and maturity it keeps on by sheer
momentum for various lengths of time after any valid bio-
logical reasons for its continuance have ceased to operate.

The relative or percentage distribution of the life span of
present-day civilized man between these three portions is, in
round figures, about as follows: roughly 21 per cent of the
whole span is spent in the infantile period as here defined, 53
per cent in the reproductive period, and 26 per cent in the post-
reproductive period. At first glance more than a quarter of the
whole of life seems to be an excessively long portion to be spent
in the running down of the machinery after the main business
of life is finished. It is, however, in no way exceptional or pe-
culiar to the human species. As an example, we have been able
to show by life table analysis that a moth, the pecan nut case
bearer Acrobasis caryae Grote, spends about 23 per cent of its
total adult life span in the post-reproductive period. And this is
a form whose total adult life span from emergence to death is
only from six to eight days long. But even with so short an
absolute sojourn for Acrobasis ^ it and civilized man both agree
in taking about the same proportionate time to make their
exits from their respective nutty worlds after they have finished
biologically justifying their existences.

But the social implications and consequences of the three-
fold partition of the life span are very different in Acrobasis
and man. What makes them so widely dtfferent is because man's

HUMAN LONGEVITY IS

capabilities and attitudes about the problem of getting a living
are different from those of any other animal, as we have seen
in the preceding lecture. In man's case the pre-reproductive
period of life is one of true infancy, in the important sense that
practically no children below the age of fifteen are or can be
completely self-supporting by their own unaided efforts. Some-
body else has to get their livings for them. It does not matter
in its general social import whether the parents do this directly
and in each instance, or whether the burden is taken over
by government and distributed over the whole social body. In
either case it is somebody other than the infants themselves that
gets their livings for them. And it is interesting to note that in
this country there is a strong and widespread body of opinion
that regards itself as enlightened, progressive, and humanitarian
in contending that the span of human infancy should be pro-
longed by law beyond its natural limits. There is a proposed
amendment to the Constitution now pending, the consideration
of which is still kept alive only by a species of political chicanery.
This amendment asserts in principle that children up to the age
of eighteen, when in the natural course of events many of them
would already be married and breeding, shall be legally forbid-
den to take any part whatsoever in the provision of their own
livings. The difiiculties that have been encountered in enacting
this philosophy into law indicate clearly enough that many
people take a dubious view of it. It will not help, however, to
call these people who are doubtful of its wisdom bad names,
or to infer that they are not quite as well aware as anyone else
of the evils and horrors of sweated child labor. They are. Their
first and frankest scepticism is over a quite different point,
namely as to whether prohibition^ is the wisest way to set about
solving social problems, or indeed whether it is a wise way at
all. They further doubt whether conditioning the child for
eighteen years to the notion that it has no responsibilities what-
ever for getting its own living is likely to be the best prepara-
tion for meeting the sad but unescapable fact of life that even-
tually it must get its own living.

The case is similar in principle for the group that finds itself

76 MAN THE ANIMAL

in the third or senescent period of the life span. A large pro-
portion of persons over fifty years of age are also not capable,
alone and unaided, of getting their livings by their own eflforts
at those ages. They either cannot get jobs, or their vital mo-
mentum has so decreased as a result of previous illnesses, acci-
dents, or the natural processes of physical and mental decay
that they could not hold jobs if they had them. In short their
efforts do not achieve the subsistence level. The cynic may jibe
as much as he likes at the findings of the recent National Health
Survey {Prelim. Refts.y Sickness and Medical Care Ser.y Bull. 7,
193 8) y that the unemployed workers showed proportionally
twice as much disablement by illness as the employed workers j
and that the ratio was still higher as between unemployables
and employed j and as between older and younger groups in
the respective classes. Any sensible person knows that even
partial breakdown and wearing out of the bodily machinery is
bound to be a major variable in the determination not alone of
employability but also of intrinsic capability to get a living any
time or anywhere.

The social and biological fact of overwhelming importance
is that the portion of the population falling in the reproductive
period, between the ages of fifteen and fifty, has to support a
great part of the rest of the population, the infants and the
old, as well as themselves. This burden includes both direct
expenditure at the time, that is while they are under fifty, and
also savings for their own old age, when they can no longer
work. And it must not be forgotten that intrinsically it makes
no essential difference whether the assumption of this burden
is directly and immediately segregated within the biological
family of parents, children, and grandparents, or is spread over
the whole social organization through the machinery of "social
security" so-called, or old age pension systems, or other similar
devices. It still remains the workers in the fifteen to fifty age
group that have got to carry the load, by and large, because
they are the only ones that produce the wealth that must pay
the cost of all the livings. This extraordinary overlapping of

HUMAN LONGEVITY 77

generations characterizes human populations to an extent per-
haps not equalled in any other living form. It is a factor of
profound importance in population biology. This tremendous
burden is borne by mankind for reasons in large part emotional.
We (in a statistical sense) care for our parents beyond the time
limits of biological necessity in good part only because we want
to. But for this emotional satisfaction we pay a high price.

In these facts is to be found unquestionably one of the basic
reasons for the practice of contraception or birth control in coun-
tries having what we are pleased to regard as a "high" state
of civilization. As the burden becomes more and more clearly
recognized the natural tendency is to attempt to reduce it by
limiting the number of children, since the emotional conflict
over the care of unborn babies versus provision for our own old
age and that of our parents is the easiest one to resolve out
of the whole assortment presented to us. But the optimism thus
engendered is in some degree illusory, because what happens is
merely that the distribution of the burden is altered, not its
total drag. For it turns out that the proportionate number of
persons falling in the middle portion of the life span — the
workers — is nearly the same in all populations of the world
today. The proportion of the infants and of the old vary widely
from country to country. But the proportion of the workers stays
relatively constant at approximately 50 per cent.

A tabulation demonstrating this point for the populations of
fifty countries, as they existed at an average date of about the
middle of the year 1 929, is too long to be shown in full here, but
Table 2 gives a condensation of this table down to workable
limits.

While this condensed table is riot as impressive as the com-
plete one, it serves to show clearly that no matter how the work-
ers' burden is shifted between the young and the old its total
remains about constant, as does the proportionate number of
workers who must bear it. Thus whether the numbers in the in-
fantile period of life are high and those in the senescent period
are low, as in the populations of Brazil and India, or whether

78 MAN THE ANIMAL

Table 2
Sex and Age Distributions of Certain Human Populations

Sex ratio = Females

Proportion in total population of

per

100 m

ales

indicated sex (percent)

Country

Age
0-14

Age
15-49

Age

50

and

Age 0-14

Age 15-49

Age 50
and over

Fe-

Fe-

Fe-

over

Male

male

Male

male

Male

male

Belgium^

98.9

102.1

102.2

25.5

24.5

55.4

54.7

19.1

20.8

Samoa

84.5
98.6

93.9
108.1

94.7
119.7

38.9
29.1

39.3
26.7

54.7
53.3

54.3

53.7

6.4
17.6

6.4

Switzerland

19.6

Germany^

98.4

114.7

115.3

30.1

27.0

52.7

55.0

17.2

18.0

United States

(Continental). .

98.0

96.6

91.0

31.6

32.1

52.6

53.0

15.8

14.9

England and Wales

98.7

113.3

116.5

29.3

26.3

52.3

54.1

18.4

19.6

Czechoslovakia. . .

98.6

109.6

116.0

30.6

28.1

52.0

53.1

17.4

18.8

Union of South Af-

frica (Natives)

98.6

95.2

150.9

41.5

42.0

52.0

48.0

6.5

10.0

Finland

96.9

101.7

118.1

32.6

30.8

51.7

51.2

15.7

18.0

Australian Con-

federation^

97.1

99.1

89.0

31.6

31.8

51.5

52.7

16.9

15.5

France

107.1

112.8

116.4

24.0

21.6

51.5

52.6

24.5

25.8

Canada*

119.4
99.0

92.4
111.7

90.1
103.3

33.7
31.8

35.2
29.6

51.2
50.5

50.3

53.2

15.1
17.7

14.5

Hungary

17.2

Greenland*

102.3

109.3

147.3

42.2

39.5

50.5

50.7

7.3

9.8

Holland

97.1

102.1

107.5

ZZ.S

31.9

50.2

50.7

16.5

17.3

UnionofSouth Af-

rica (Whites). . .

97.4

95.2

82.2

36.7

37.9

50.2

50.7

13.1

11.4

Denmark^

98.5

106.4

115.2

32.2

30.2

50.2

50.6

17.6

19.2

Sweden

96.0
96.2
93.9

102.1

108.1

81.9

120.0

142.3

97.2

30.5
45.0
39.2

28.3
41.3
41.6

50.1
49.8
49.6

49.3
51.6
46.0

19.4

5.2
19.2

22.4

Guam

7.1

British India

12.4

Lithuania'

98.6

116.3

111.4

32.6

29.2

49.3

52.5

18.1

18.3

Japan

97.7
96.7

96.2
115.8

104.2
129.0

35.1

35.2

35.0
30.6

49.0
48.6

48.1
50.6

15.9
16.2

16.9

Portugal

18.8

Spain

99.1
95.2

109.3
103.2

112.7
131.0

35.6
34.8

31.6

48.5
48.5

49.8
47.5

15.9
16.7

16.9

Ireland

20.9

Brazil

97.2
99.5

99.9

113.7

97.0
119.9

43.0
41.8

42.5
39.4

48.2
47.6

48.8
49.9

8.8
10.6

8.7

Colombia

10.7

Bulgaria

95.4

105.5

95.8

37.2

35.4

47.1

49.6

15.7

15.0

Russia (in Europe)

101.3

147.0

121.2

45.2

37.4

39.6

47.6

15.2

15.0

^ Excluding Eupen and Malmedy.

2 Excluding the Saar region and Eupen and Malmedy, but including Schleswig Hol-
stein. ' Native population only.

' Excluding the native population. ^ Excluding the Faroe Islands.

* Including Eskimos and Indians. "^ Excluding Melme.

HUMAN LONGEVITY

79

the reverse situation obtains as in the populations of France
and Sweden, the number of workers still remains constant at
about 50 per cent, and so does the total load they have to carry.
As we go down the table it is seen that as the first column of
figures — the percentage in the population of persons in the pre-
reproductive period — decreases, the figures in the last column
increase — the percentages in the post-reproductive period.

THE LIVmG POPUJi^TIOn

The

Old

50&'0vet

Fig. 15, Approximate averag-e distribution of living- human population.

Frequencies are depicted as areas.

The situation may be graphically generalized in the manner
shown in Figure 15.

The bottom half of the square, representing half the popula-
tion, supports the upper half, which may be divided variously
between the children and the old, but always still remains
about a half of the total population.

On the basis of this natural biological classification of the age
distribution Sundbarg distinguishes three types of fopulatiofiy
the progressive type, the stationary type, and the regressive
type. His definitions of these types are that, on a percentage

80 MAN THE ANIMAL

basis, in all types 50 per cent of the total falls in our worker
group aged 15 to 49 inclusive, while in the progressive type
of population the percentages of infants and senescents are
respectively 40 and lOj in the stationary type 33 and 17 j and
in the regressive type 20 and 30. These are, of course, arbitrary
figures but in a general way do correspond with reality. From
the point of view of population growth Brazil, India, and the
Argentine are in the progressive state, while England, France
and Sweden are in the regressive state.

We must stop at this point, but perhaps enough has been said
to make it plain that man's life span, and its prolonged periods
of infancy and senescence, are of great potential importance in
connection with his sociality, and human biology generally.

Lecture IV -^

THE NUMBERS OF MEN

In the lectures that have preceded this we have examined some
of the more important respects in which man the animal is
uniquely different from all other animals. In this survey very
little was said about one of the most important of man's biologi-
cal characteristics that he shares not only with other animals
but with all other living things, namely the capacity and urge
to reproduce. This urge is a powerful one — nearly the most
powerful known in the whole realm of biology. And its con-
sequences to humanity are far-reaching. They lie at the root
of our most serious and baffling social problems and troubles
today. All over the world a great deal of emotion is being spent
and thought exercised over such matters as poverty, unem-
ployment, social unrest, war, and human misery generally. Not
only governments but also ways of living generally are almost
everywhere being radically altered in the pathetic hope that we
shall by this process suddenly emerge into a new and better
world. Yet ever since man has existed there surely has been
poverty (because men have always had unequal talents and
luck in acquiring goods) j there has been unemployment (be-
cause men have been unequally endowed in respect of laziness
and capacity) \ there has been social unrest (because the zest
for trouble-making was never exactly equally distributed among
men — if it had been the uniform dose to each individual would
have been too small to produce any physiological effect) ; there
have been wars (because man is by nature a fighting animal) j
and there has always been misery (because talent for being

81

82 MAN THE ANIMAL

miserable is a peculiarly human trait). But the great point is
that while all these dreadful things have always existed, serious
concern and excitement about them has, on the whole, grown
just in proportion as the numbers of men — the sizes of popula-
tions— have increased. So then we shall devote this lecture
to some consideration of the numbers of men — human popu-
lations as they exist today, how they got that way, and the im-
plications they may have for human biology generally.

A recent analysis (Pearl, The Natural History of Population,
1938), has led to certain broad results and principles that seem
to throw light on the general biology of population considered
dynamically. Perhaps we may start with a brief statement of
these results. In the nature of the case the statement will have
to be categorical, because there is not time to present the de-
tailed evidence. I regret that this is so. But I think the material
painstakingly gathered together may fairly be said to have
made the following general relations clear.

1. The major problems of population are primarily and
fundamentally biological in nature, because the size and other
characteristics of populations rest upon the operation of the
basic biological principles of individual survival, reproduction,
variability, and their mutual interactions and integrations with
the environment.

2. The state of any particular population at any particular
moment depends primarily upon and is determined by the
manner in which the specific biological elements that influence
fertility have been, and are, acting, in the direction either of its
promotion or its restriction.

3. There is great variation among individuals and groups in
the biological elements that influence fertility, such as fre-
quency of coitus in wedlock, age at m.enarche and at menopause,
and other similar physiological and behavioral matters.

4. The basic biological pattern of human reproductivity is
inherently and intrinsically different in a number of important
respects from that of other mammals and animals lower in the
evolutionary scale, and has been rendered still more widely
divergent by artificial alterations that man has consciously and

THE NUMBERS OF MEN 83

deliberately made in his own intrinsic pattern of reproductivity,
particularly through such things as the practice of contraception,
postponement of marriage until long after puberty, and other
factors of a comparable sort.

5. In the population of the United States, at least, differ-
ential fertility relative to race (Negro versus white) and to the
three most important social class differentiations (economic,
educational and religious) are due primarily to differences in
the relative prevalence and effectiveness of the efforts made to
prevent conception, correlatively aided by relative frequency
and postponement of marriage, and the practice of criminal
abortion, and to practically nothing else.

6. But in this same United States population it appears in
high degree probable that the general level of fertility, and
particularly the steady decline of total fertility that is now going
on and has been in the recent past, both in the population as a
whole and in differentiated classes within it, cannot be justly
regarded as due solely, or possibly even primarily, to the opera-
tion of the forces that have just been enumerated. Other, and
more obscure factors are involved, about which literally almost
nothing of a precise and definite character is now known.

While the evidence that has been offered here in support of
the six general points that have been enumerated has come
largely from one population only, that of the United States,
it seems plain that the same principles and forces are operating
in all populations, in widely different and varying degrees and
extents, to be sure, but always and everywhere in some degree.
if this be granted, as seems reasonable, it then follows that in
the population of the world as a whole we are presented with
the objective record, at any particular time, of the net integrated
effect of the operation of all these complexly interrelated factors
and forces that have been enumerated. So then let us now turn to
an examination of the population of the world.

II

It should be emphasized that it is as impossible now as it has
always been in the past, and will be for a long time in the future,

84 MAN THE ANIMAL

to know exactly how many human beings are or were living on
the face of the earth at any stated moment. The primary diffi-
culty arises from the fact that the process of census counting has
never included all the people or areas of the globe j and a
secondary one from the fact that in different countries censuses
are taken on different dates and with widely differing degrees
of accuracy. But the situation grows steadily more encouraging.
At the present time it can be said that something of the order of
75 per cent of the present population of the world is either
regularly counted in recurring censuses, or has been counted at
some time in the past, or at least an attempt has been made at a
count. Of the wholly uncounted residue, for which there have
never been many figures except estimates as a base, China consti-
tutes by far the major portion. According to what seems to be
the most reliable estimate, China's population at the present time
constitutes something of the order of 22 per cent of the world
total. When China takes a real census, if she ever does, the
study of world population will then rest upon a basis of suf-
ficient statistical security to justify a very substantial degree of
confidence in results and inferences.

It is the practice of our laboratory to make from time to time
revisions of the figures for world population. The plan used is
to assemble separately on work sheets the latest available data
regarding population, area, and time (date of count or estimate)
for each of the smallest areal and political divisions of the earth
for which data are available, and then combine them into larger
divisions by summation, checking the figures at each stage in
every way possible.

The data of three recent revisions are given in Table 3.

The steady decline in the area figures between the successive
revisions appears at first glance completely paradoxical, not to
say verging slightly on the idiotic. The earth's surface is plainly
not shrinking at any such rate. The land area of the globe
apparently shrivelled, according to this table some 717,212
square miles between average dates of 1930.1 and 1934.7. All
that this means is that two things have happened. The first is

THE NUMBERS OF MEN

85

that more accurate surveys of outlying parts of the world are
being made available each year. These have led in recent years
to official revisions of area particularly in French West Africa,
Venezuela, Iraq, Nicaragua, Tanganyika, and Southwest Africa.
The results of these surveys, as they become available, we
incorporate in our revisions. In the second place we are in-
creasingly able to make corrective deductions for the areas
included in inland waters (lakes, broad rivers, etc.), which
formerly were counted as land area.

Table 3
World Population

Area (sq. miles)

Total population (in millions) . . .
Density (persons per sq. mile) . . .
Mean date to which figures apply

1934

revision

52,139,677
2,050.4
39.3
1930.1

1935
revision

51,742,763
2,073.3
40.1
1931.5

1937
revision

51,422,465
2,104.8
40.9
1934.7

Our figure for total world population of 2,104.8 millions is
a little greater than the latest League of Nations figure, which,
is 2,095.0 millions. But obviously the two world estimates are
in substantial agreement, the difference being less than one-half
of one per cent of the mean of the two estimates.

The mean density of world population between 1930 and
1935 appears to have been almost exactly identical with that of
continental United States at the 1930 census — about 41 persons
on the average for each 640 acres of the earth's land surface.

The af parent mean annual growth rate per cent of the world
population between the mean dates 1930.1 and 1934.7 is 0.58
per cent j that is six-tenths of a person added in each year net to
the living population for each hundred living at the beginning
of the year.

It is, however, uncertain as to how much significance should
be attached to these apparent growth rates, because of the fact
that they include at all stages purely estimated population

86

MAN THE ANIMAL

figures, as well as counts and legitimate short intercensal extra-
polations from counts. If we deal only with those countries (or
other political subdivisions) for each of which there are avail-
able data from which a separate individual growth rate can be
computed — 134 "items" at the 1934 revision, 140 "items" at
the 1935 revision, and 158 "items" at the 1937 revision, each

Table 4

Recent world population growth-rates for those countries only for which the
necessary data are separately available

Information

Area (sq. miles)

Percentage of total world
area

Latest population (in thou-
sands)

Percentage of total world
population

Mean date for latest popu-
lation

Earlier population (in thou-
sands)

Mean date for earlier popu-
lation

Mean annual growth-rate
percent

Length of period (years) on
which rate is computed . .

1934

revision

38,095,193

73.1
1,421,293.2
69.3
1930.42
1,276,299.5
1920.45
1.14
9.97

1935
revision

1936
revision

38,369,596

74.2
1,465,646.5
70.7
1931.89
1,326,170.8
1924.06
1.34
7.83

40,478,875

78.5
1,524,340.3
73.9
1932.95
1,393,842.3
1925.39
1.24
7.56

1937
revision

42,502,783

82.7
1,577,307.8
74.9
1934.87
1,465,280.3
1928.01
1.11
6.86

"item" being a country or political subdivision — ^the results
shown in Table 4 are obtained.

It is evident from the second and fourth lines of this table
that the areas and populations included here are substantial
percentages of the world totals. Furthermore the figures include
none of the very doubtful data (particularly those for China)
necessarily embodied in the earlier table. On these two grounds
of large proportionate size of sample and relatively greater
reliability of the data it is reasonably to be expected that the
growth rates of the table before you probably represent more

THE NUMBERS OF MEN 87

accurately the general situation than the apparent rates derived
from the figures of estimated total world population.

In the light of the data presented it may be tentatively sug-
gested that the population of the world as a whole has been
growing in the recent past at a rate of something of the order
of one per cent per annum — perhaps a little more, perhaps a
little less, but at about that figure. This would mean, if con-
tinued without change, a doubling of the present world popula-
tion in about seventy years. There is, however, no reason to
suppose that the total population of the world will ever, in its
present cycle of growth, at least, be double what it is at the
present time.

It seems reasonable to conclude from a great body of avail-
able data that the mean annual growth rate per cent for the
world population is steadily decreasing at the present time, and
has been during the recent past. In other words there is a general
decline of fertility that appears not to be exclusively confined to
highly "civilized" countries, where the populations are most
sophisticated and eager and adept at birth-controlling. It seems
rather to be a world embracing phenomenon — something affect-
ing man as a species. But, as will appear clearly in a moment,
it is a phenomenon of historically very recent appearance, in
comparison with man's total span of existence on the earth as a
distinct species. The world-wide decline in fertility is certainly
a much more recent thing than the making of efforts at contra-
ception. On the evidence it appears likely that the marked slow-
ing up of the growth rate of world population per unit of time
did not begin until about the beginning of the present century,
or in the preceding decade. But nearly two centuries ago Short,
in his entertaining treatise on the population of England — per-
haps history's most venomous diatribe against the establishment
of hospitals and homes for foundlings, usually considered an
innocent form of altruistic behavior — has repeated references to
the prevalence of contraceptive practices. As an example he
deplores the fact that in "Cities and great Towns . . . the
wicked Arts of preventing Conception are more generally known

88 MAN THE ANIMAL

and used" than in rural habitats. These examples sufficiently
indicate that long before the world population began to slow
down in its growth rate, enough contraceptive effort was being
made in the western world, at least, to worry some students
of the matter.

Ill

In 1924 I published a logistic curve fitted to the data as-
sembled by Knibbs to indicate the growth of population of the
world, from the estimate of Riccioli in 1 660 up to and including
that of Knibbs himself as of 1914.

It became apparent some time ago that this original world
logistic needed revision badly, because by 1930 the population
of the world had already exceeded the upper limit set by the
curve. Consequently we have recently brought the old curve
up to date, adding five more estimates of world population since
1914, the latest being our own of mean date 1931.5. The new
logistic curve is shown in Figure 16.

As might reasonably be expected, the estimates of world
population have been strewn irregularly about a trend line that
may perhaps be fairly regarded, taking all the circumstances
into account, as reasonably represented by the logistic curve.
The nature of figures that have to be used in lieu of "observa-
tions," which even at the present date represent only about
75 per cent of complete actual observation, precludes the pos-
sibility of ever getting anything like a really smooth fit with a
four-constant curve. But taking the material for what it is, with
all its inherent disabilities, a number of interesting points are
presented for discussion.

In the first place the upper limit of the current cycle of
growth is raised by about 31 per cent of the former figure, to
a new value of 2645.5 millions. According to the curve this
colossal total will be closely approached around 2100 a.d., pro-
vided nothing happens in the meantime to alter seriously the
present trends of reproductivity. No formal prediction is made,
however, that this will represent the ultimate size of the world's

THE NUMBERS OF MEN

89

human population. It is only an extrapolation from the available
evidence as to what the past history of world population growth
has been up to the present time. No other interpretation than
this should be put upon it. It is a figure that future events and
trends now wholly unpredictable may alter, just as proved to be
the case with the former extrapolation.

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Fig. 16. The population growth of the world from the seventeenth century to
1931-32. The circles give the observations, and the smooth line gives the graph

of the logistic equation

The present logistic cycle of world population growth got
discernibly under way at about the middle of the seventeenth
century — say three hundred years ago in round figures — and
started from a lower asymptotic value of about 445 millions.
This isj of course, only an estimate, but cannot be far away from
what was the actual fact. Indeed all competent students of
population agree on a value of about this general magnitude
for the time stated. Since then the world's population has in-
creased to about 2105 millions, again in round figures, as of an
average date of about 1935. In other words there has been in

90 MAN THE ANIMAL

roughly three hundred years a 4.7-fold multiplication of human
beings on the face of the earth, and this present cycle of growth
appears to be only about two-thirds completed. A nearly five-
fold net multiplication of the population of a species with such
relatively poor reproductivity as man displays, in a time period
of only about three hundred years, is certainly a noteworthy
phenomenon demanding the most serious consideration.

But man, as a distinct and differentiated species, had been on
the earth an extremely long time prior to the seventeenth cen-
tury. Few, if any, anthropologists nowadays question that he
had become differentiated and was making flint tools of the
pre-Chellan type early in the Quaternary, certainly some-
where in the first inter-glacial period. Nor is it doubted that
from at least that time he has continued on the earth in an
unbroken succession of generations j through the long second
and third inter-glacial periods and the glaciations that separated
them. Geologists, anthropologists and archaeologists seem, how-
ever, not to have been able, up to very recent times, to agree
as to the number of calendar years it took man to climb this
long evolutionary ladder. Lately, however, Zeuner has syn-
thesized all the evidence in a masterly way, with results that
warrant and appear to be receiving general acceptance, so that
it may be hoped that the timing of prehistory may be at last
regarded as reasonably settled. He reaches the conclusion that
Homo heidelbergensis from the Mauer sands (the oldest find
in Central Europe) has a probable date on the absolute time
scale of about 500,000 years before 1800 a.d.

So then the following situation is presented for our con-
sideration. In the 500,000 odd years from the time that man
got under way as a distinct zoological entity, up to about 1 630-50
say, he had certainly increased in numbers in the normal bio-
logical way of things. He may be presumed to have multiplied
during these years as rapidly, on the whole, as his inherent
biological equipment and the circumstances of his natural en-
vironment would permit. Yet the total world population in
1630 was only 445 million, with a density of a little over eight
persons per square mile as against the present forty-one.

THE NUMBERS OF MEN 91

This being so at least three possible alternative inferences
present themselves. The first of these is that the human popula-
tion of this globe more or less steadily grew for 500,000 years,
but at an extremely slow time rate as compared with the growth
performance of any but a very few populations now existing.
On this hypothesis it may be regarded as probable that growth
of world population was not entirely steady and continuous
along a smooth curve, logistic or other, but instead was irregular,
fluctuating up and down about the ever rising time-trend line.

A second possible alternative is that for a long time — thou-
sands of years — prior to the seventeenth century the population
of the world stood stable at between roughly four and five
hundred million, or oscillated in waves of relatively small
amplitude about some such figure. On such a view this value
would represent a relatively stable upper asymptotic level
achieved in a cycle of population growth that was consummated
long before, and at a relatively early stage of man's evolution.

Finally a third possible alternative is that during some period
or periods in this vast span of 500,000 odd years of man's life
on the earth the world f ovulation was much higher than 445
million, and subsequently lessened, for reasons wholly unknown,
to reach that final figure at the time when reasonably reliable
population history begins.

Which of these three alternatives is true? No one can say
with any authority. But all the relevant evidence seems to
indicate that there were as many (or more) human beings living
on the face of the earth in 1630 as there ever had been at any
prior time since man set up in business for himself. Most par-
ticularly, to be counted against the third alternative is the fact
that until recent times man's culture was not of the sort to
make possible the existence of large populations on the earth.
As was pointed out in the preceding lecture hunting, pastoral,
and primitive agricultural cultures are not compatible with large
total populations, as we know them nowadays, because high
densities cannot be supported at these cultural levels or stages.

Similarly the evidence seems definitely to be against the
second hypothesis.

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Fig. 17. Diagram to illustrate alternative hypotheses as to the history of the
human population of the earth. The portions of the curve drawn in broken lines
are purely hypothetical, except as to the total time scale. The portions of the
curves depicted by a continuous solid line (1630-1930) represent the known
facts as to world population growth, and are plotted to the same time scale as

the earlier portion

THE NUMBERS OF MEN 93

So then we are left with the first alternative, a very slow and
irregular time rate of growth of world population over a very
long time prior to the Middle Ages, let us say, followed by a
relatively tremendous spurt of growth not yet ended.

The implications of the three alternative hypotheses will be
made plainer by the diagram shown in Figure 17.

For reasons of practical convenience in drawing and repro-
duction this diagram is scaled as though the total period of
man's life on the earth prior to the 1 7th century was a span of
100,000 years instead of the 500,000 that seems undoubtedly
much nearer the truth. The diagram understates the case by
so much.

How is this sharp spurt of population growth after 1930 to
be explained? The primary cause behind the new cycle of logis-
tic growth of world population that started in the seventeenth
century seems clearly to have been that mankind first became
aware at about that time that its effective universe was expand-
ing. The earth was not growing physically bigger to be surej
there were no new acres of land being really added to the planet.
But many were being discovered, uncovered, and put to use,
and, in general, man's effective universe for purposes of living
certainly was expanding j and at an accelerating rate. This was
being brought about by new discoveries and new ideas that
made it possible for man to exploit far more effectively than he
had known how to before, the natural resources for human
living inherent in the earth on which he lived. One of the most
important and obvious aspects of the expansive changes in man's
effective universe that have appeared in the last three hundred
years was the ever increasing facility of communication and
transportation, with its consequent broadening of the base and
acceleration of the temfo of trade. Indeed it was the develop-
ment of railroads that had a large part in making the gloomy
prophecies of Malthus about the future of mankind at the end
of the 18th century seem comically absurd soon after he made
them. Another change of similar sort was the development of
relatively cheap and highly effective power, associated in the

94 MAN THE ANIMAL

first instance with the discovery and rapid improvement of
practical steam engines. In generalized terms what expanded
man's effective universe, and made possible a great spurt of
population growth was scientific discovery and the application
of its results, in the broadest sense including exploration as
well as technology, to man's basic problem of how best to cope
with and exploit his natural environment.

To this day, peoples who because of geographical location,
climatic conditions, general stupidity, and other causes, have
been unable to participate in any real sense in the consequences
of an expanding effective universe, are still growing in popula-
tion verp slowly, if at all. The conditions of living, and particu-
larly the difficulties of getting a living, in the more primitive
stages of culture where the individual wrings his living out of
a raw and untempered environment by his own direct efforts,
do not permit rapid population growth any more now than
they ever did.

IV

The most obvious direct and objective consequence of the
great spurt of world population growth that has occurred in
the last 300 odd years is the increase in average density of
population that it has entailed. It will be well to examine the
facts about this in some detail.

The population of the earth is distributed with great uneven-
ness over its land surface. This is shown in Figure 18.

This table is arranged in order of ascending density classes
(persons per square mile). It is based upon 906 separate po-
litical or administrative units for which separate data are avail-
able as to area and population. By "political unit" is meant
either a country, or a state, or a department, or a canton, or a
colony, protectorate, or territory, or in a few cases a city having
separate administrative status equivalent legally and politically
to that of a state. Each such separate political unit was put in its
appropriate density class and the areas and populations summed

Land Area 1939 Population

NEW
WORLD

OLD
WORLD

1 NORTH AMERICA
(MOF MEXICO)

iCENIAMaCARIB.

SOUTH AMERICA

^EUROPE EXC. USSR

U.S.Si^.

ASIA EXCUSSR

AFRICA

OCEANIA

TOTALS

100%

100%

Fig. 18. Percentage distribution of land area and population for the main
divisions of the earth, as of approximately the year 1939

96 MAN THE ANIMAL

for the class. These absolute figures were then reduced to the
percentages shown in the table. Thus the first density class,
0-9 persons per square mile, includes 147 "political units" whose
aggregate area is over 29 million square miles. Even the highest
density class (3100 and over persons per square mile) with only
fourteen "political units" has an aggregate area of over 1200
square miles.

The first and most striking general fact that is evident from
the table is the extreme skewness of the distribution of popula-
tion density over the earth's surface. Taking the mean densities
of the several classes as a conservative basis for estimating the
range of intensity of human crowding upon the earth it is seen
that about 36 per cent of the political units cover only 0.3 per
cent of the whole range of population densities; and even
77 per cent of the political units cover less than 2 per cent of
the total range of densities.

This skewness has come about initially through the self-
interested desire, and eventually the social and economic neces-
sity for large numbers of people to live together in cities. This
process of urbanization down through the ages has led to the
formation of the great metropolitan centers, or "conurbations"
as Fawcett calls them, in which so large a proportion of present
day men live out their allotted spans. They represent one of the
many quaint ways in which mankind is coming to resemble
more and more clearly the termites in modes of life and social
philosophy.

The matter may be looked at statistically in other ways that
do not involve consideration of the separate political units. Well
over a half (57 per cent) of the total land area of the earth is
occupied by only four and a half per cent of the total popula-
tion of the world. And about 81 per cent of the earth's total
land area contains only 18J4 P^r cent of the world's population.
Only a little over 5 per cent of the land area of the earth
(densities of 200 and above) contains nearly 52 per cent of its
population.

Figure 19 emphasizes graphically certain broad facts of the

THE NUMBERS OF MEN

97

distribution of world population over the land surface of the
earth.

The area of the whole square is taken as that of the land area

Total Land Area of the Earth

AND

Inhabitants per S'guARE Mile

Fig. 19. Land area of the earth and population density. For further

explanation see text.

of the globe. The lower unshaded rectangle — the "great open
spaces" comprising roughly 81 per cent of the whole area —
has an average density of population of only about 9 persons
per square mile. The cross-hatched rectangle at the upper left

98 MAN THE ANIMAL

corner comprises just over 13 per cent of the whole land area,
and contains a little over a quarter of the total world popula-
tion living at the not too unreasonable average degree of crowd-
ing of about 86 persons per square mile. Finally, the little black
rectangle in the upper right corner comprises only just over
5 per cent of the total land area, but contains over one half of
the whole world population. This moiety of poor humanity
lives at an average density of 394 persons to the square mile.
All told we have in this diagram a picture of the net biological
result that human civilization had wrought by its efforts up to
the year of grace 1930.

The average density of world population as a whole is nearly
41 persons per square mile, as we have seen. Yet the populations
on over 8 1 per cent of the total land area are living at densities
under 40. About 14 per cent of the population of the world —
roughly one person in seven — is living at densities of 600 or
above, that is with one acre or less per person, on an even
personal distribution of area. Now as a rough and round figure
it is estimated by Brown, a competent and conservative authority,
that 2.5 acres are needed to support a human being. Obviously
this implies good land, and all of it intensively cultivated. But
neglect these latter points for a moment, so as to put the best
case possible. If we take the 2.5 acre figure at its face value
and with the obviously too optimistic assumption that all land
functions at that scale, then in order to get the means of sub-
sistence to something over a half of the world's population
today will involve a significant problem of transportation and
distribution. Here one of the principal villains of the socio-
economic melodrama enters the scene. It is one of the commonest
of assertions that the faults and troubles connected with the
"distribution" of goods are chiefly to blame for the world's
woes, with the implication that if these faults could be elimi-
nated the world's economic troubles would largely disappear.

But, faults or no faults, the present geographical arrange-
ment of world population makes it plain that without substantial
"distribution" of the means of subsistence from the places where

THE NUMBERS OF MEN

99

they are produced to the places where they are used, something
over a half of all human beings could not go on living at all.
Somebody must haul to these city dwelling near-termites with
only two legs, much too large heads, and no exoskeleton, all
that they eat, all that they wear, and everything that protects
their soft bodies from the rigors of the physical environment.
Furthermore this transport must never cease. If it stops for
even a short time Death stalks in and starts his reaping, dis-

Table 5

Twenty most densely populated countries

Persons

Country per sq.

mile

Belgium 704.9

England and Wales 700.0

Netherlands (excluding water

area) 674.2

Japan (proper) 469 . 2

Germany 369.3

Italy 355.2

Czechoslovakia 280.0

Switzerland 261 . 2

Hungary 250.6

Poland 228.1

Persons

Country per sq.

mile

Denmark 224.6

Austria 208.8

Portugal 205.7

India 204.8

France 197 . 1

Jugoslavia 158.8

Bulgaria 157.0

Rumania 153 . 7

Greece 136.0

Spain 126.4

criminatingly mowing first the lush meadows where the lower
castes grow, but very quickly getting on to the aristocratic
uplands, where the growth is sparser but more choicely flavored.

The next table, Table 5, shows the number of persons per
square mile in the twenty most densely populated countries of
the world, according to the latest figures (our 1937 revision),
leaving out China as doubtful.

This table plainly is about equivalent to a catalogue of the
European nations. Only two non-European countries appear
in it (Japan and India).

Taking a world view, it is evident that the increase of
urbanization has by no means reached its end. On the contrary
it is still going on, and, on the whole, at an ever accelerating
pace. In a broad sense the most striking thing that has taken

100 MAN THE ANIMAL

place in regard to agriculture during the last fifty years, not
alone in the United States or Canada or Argentina but in some
degree more or less all over the world, is that the progressive
development of new knowledge, improved techniques and fuller
application of power and machinery have made it possible for
fewer human beings to produce more of everything than was
formerly the case.

From the point of view of population density an odd sort of
paradox results. Social and economic forces and modes of
thought that are fundamentally identical — namely, applications
of new discoveries, improved machinery, better transport, and
communication, to the business of getting a better living — work
in opposite directions when applied to agriculture and to the
manufacturing type of industry so far as concerns the trend
toward human crowding. On the one hand, the movement is
toward a still lower density of population in agricultural regions,
already the most sparsely peopled portions of the earth's surface
capable of supporting any substantial population at all. On the
other hand, there is the trend toward an ever higher density —
still greater crowding — in urban industrial centers, already most
densely populated. What makes the paradox is that identically
the same set of forces, at bottom, is producing these diverse
results.

The same principle applies to a considerable extent as between
mother countries and their colonies or other dependencies.
Densely populated countries with small areas, like those of
Europe, and Japan, are highly industrialized and commer-
cialized. They cry for more land so that their people may
spread out. But their nationals, by and large, refuse to leave the
homeland in any considerable numbers to settle in the fair
but sparsely populated regions available to them. Italy, for
example, had succeeded up to the time of the World War in
placing only about 8,000 of her people in all her African
colonies together. Again, the colonial empire that was Ger-
many's on July 1, 1914, had, all told, but a meager 24,000 or so
German inhabitants.

THE NUMBERS OF MEN 101

National as well as individual psychology is involved. Na-
tions have their pride as well as individuals. As they look about
the world they perceive an unequal distribution of the richer
lands.

The greatest problem that confronts every single soul that
makes one of the units that add up to these colossal human
aggregates we have been considering is: "How shall I get a
living?" For the science of biology is quite dogmatically sure
about one thing. Every living organism must get its living or
perish. Life is a dynamic process. It requires a constant flow of
energy and matter to keep going.

The logical consequences of this purely natural law are
obvious, in a broad sense. Each living organism, including each
man, woman, and child, either must get its own living, or an
arrangement must be made such that somebody else gets the
living for it. We, and a good many other organisms, arrange
to get the livings for our babies — embryos and still undeveloped
young — until they are biologically able to fend for themselves.
Mankind, to an enormously greater extent than any other
species, makes similar arrangements for the continued living of
other categories of individuals — notably the aged, infirm, defec-
tive, and degenerate — incapable on their own resources of
keeping their vital fires alight. The fact that man does this is
probably the chief reason why he regards his species as a noble
one, a view in which it is doubtful whether the true termites
would concur. But never mind about termitodoxic moral judg-
ments for the moment. The important thing is that a very
considerable number of persons how on this earth who are
neither babies, nor aged, infirm, nor defective, find themselves,
or think themselves, completely unable to get their livings by
their own efforts.

What is going to be done about it? Some say one thing, some
another. The view that, on the whole, seems to be most gen-
erally favored in the United States at the present time is that

102 MAN THE ANIMAL

those who are getting a living for themselves shall support
those who are not. This is a biologically possible temporary
solution, there as elsewhere, chiefly because the extravagantly
lush bounty of this good earth of ours, the true "unearned
increment," has not yet been entirely exhausted. And until it is,
there is plainly no reason why we should not average up the
pleasures of human living, if it pleases us so to do — reducing
them for some to the end that they may be increased for others.
But this process will continue only so long as it causes the fit and
industrious no serious discomfort, and does not threaten their
survival.

The checks to bad behavior aflForded by social organization
are extremely feeble and ineffective things when groups of men
are, or think they are, threatened with biological elimination,
or even with the discomfort of a definitely lowered standard of
living. Events of the last few years in Asia and Africa, and still
more recently in Europe, leave no doubt on this point. "Live
and let live" is a fine and noble maxim, but it works prag-
matically only so long as there is enough "living" — that is,
desired good things that make living pleasant — to go around.
Men as individuals and as groups will beg, steal, fight, murder,
and otherwise demean themselves to the level of other beasts
not yet "civilized," in order, hopefully, to ensure the continued
survival of themselves, their own flesh and blood, and their
kind, if they feel that survival is threatened.

Some persons find it difficult to understand or to admit such
a view of the ultimate human behavior pattern. They see most
people not only living peaceably, most of the time, but also at
considerable expense of time and money keeping alive ever-
growing numbers of biologically unfit persons. The physically
and mentally defective and degenerate, as well as the very
young and very old, are taken care of in a manner unparalleled
in any other form of life except man's. In the course of history,
this process has become largely socialized, first through re-
ligious organizations, then through private groups of laymen,
until, finally, more and more of the burden has been spread

THE NUMBERS OF MEN 103

over the whole fit population as a recognized function of
government.

Each individual man, woman, and child now living has avail-
able for its living and all the activities associated with and
derivative from human living, under sixteen acres of land count-
ing all the land, good, bad, and indifferent together, and prob-
ably nearer half of this number of acres of land really good for
anything, in the literal sense of the words. This is a meaningless
and fantastic average if it is thought of in the sense of forcibly
attaching each individual human being to a particular sixteen
acres of the earth's surface. But it is an average fraught with
the deepest meaning in a world view, when it is remembered
that in last analysis all the means of human living, whether by
the agricultural, industrial, commercial, or any other method,
are derived, directly or indirectly, from the inexpansible earth
and the energy from the sun's rays.

In the meantime the world's population keeps on growing,
even if at a slowing rate, and the earth on and from which man
must live is not an inexhaustible source of the means of living.
Jacob G. Lipman, a recognized authority on the biology and
chemistry of soils, has recently pointed out that whereas, on
the average the four elements oxygen, silicon, aluminum, and
iron make up about 87 percent of all known terrestrial matter
(including lithosphere, hydrosphere, and atmosphere) these
elements, with the exception of oxygen, constitute only an
insignificant fraction of organic matter, the matter of living
things. The solid matter of a man reduced to ash and analyzed,
contains about 0.0001 per cent of aluminum, 0.03 per cent of
iron, and 0.005 per cent of silicon. On the other hand 54 per
cent of the dry matter of man— ^merely reduced to complete
dryness but not burned to ashes — is carbon. This element all
living organisms get, directly or indirectly, from the atmosphere
or the lithosphere, or both, each in its own way; and by their
vital processes all build it into their living structure, of which
it is the keystone of the arch. But of the total known terrestrial
matter, again including lithosphere, hydrosphere, and atmos-

104 MAN THE ANIMAL

phere, carbon constitutes on the average only 0.08 per cent.
And of this, only about one two-hundred-and-fiftieth part is
in such form as to be directly usable by plants, animals, and
men for the purpose of their living. The great bulk of it is in
insoluble forms such as coal and oil, where it was laid down
by the living beings of past geological eras after they had
finished with it. For the carbon cycle is, in considerable part, a
degradative one from the standpoint of living things. The total
store of carbon that is directly usable by and absolutely neces-
sary to organisms for their growth and living tends constantly
to diminish by being transferred to insoluble forms.

The position regarding carbon will be clarified by the follow-
ing quotation from Lipman:

"Under the head of debits, we may note the assimilation
annually of more than 16 billion tons of carbon by vegetation.
There is the fixing of large amounts of carbon in the weathering
of rocks and in the formation of insoluble carbonates. An equiva-
lent of 5 billion tons of carbon is fixed annually through the life
processes of sea organisms. Altogether, it appears that the carbon
dioxide withdrawn from the atmosphere by plants is balanced
by that added to the air by microorganic and other processes in
the soil. By way of further clarification, we should note that the
carbon given off by the soil comes partly from the destruction of
organic matter and partly from root respiration. According to
the investigations of J. W. Shive, the root respiration of a corn
crop amounts to about 35 per cent of the quantity of carbon fixed
as organic matter by this same corn crop. If this ratio is extended
to the entire plant world, it would mean that about 7,000 of
the 19,000 million tons of the carbon addition diffusing from
soils can be credited to root respiration, leaving 12,000 million
tons due to the destruction of organic matter. If we add the
7,000 million tons of carbon transpired by roots to the 16,300
million tons of the carbon assimilated by plants, we obtain a
total of 23,300 million tons of carbon utilized annually by
vegetation. The release through soil respiration is but 19,000
million tons."

THE NUMBERS OF MEN 105

While carbon is the keystone it is not the whole organic arch.
The story of annual net loss of the stuffs of life is similar for
other essential chemical elements. Lipman estimates that the
soils of the United States suffer the following annual net losses:
of nitrogen 2.7 million tons 5 of phosphorus 1.2 million tonsj
of potassium 30.7 million tonsj of calcium 43.2 million tonsj
of magnesium 14.2 million tonsj of sulphur 1.1 million tonsj
and of organic matter generally 222 million tons.

Let it not be supposed that the problem concerns food alone,
or that mankind is scheduled to perish miserably by starvation
in the next fortnight. The problem of adequate food production
for the present or an even larger world population is not the
most serious aspect of the matter. The industrial and com-
mercial modes of life that are in an obligate way essential to
the maintenance of our dense urban populations are using up
their basic resources at an even faster rate than that of soil
exhaustion. To support a world increase of population of about
two and a half times between 1800 and 1918, coal, and pig iron
production had to be increased about a hundred-fold.

There seems to the biologist some reason to believe that man-
kind is at the present time engaged in the process of biologically
adjusting or adapting itself to the situation that has developed
as the combined result of the growth of scientific knowledge and
the tremendously accelerated growth of population that that
increase in knowledge has fostered in the last three hundred
years. This adaptation appears to be going on in what must be
regarded as the normal biological way, namely by processes that
are not, for the most part, the resultants of conscious group
effort or planning, and may therefore be designated as natural,
insofar at least. Birth rates over a large part of the world are
generally falling, and have been falling for a considerable time
past. This decline in human reproduction is nowhere a conse-
quence as yet of a type of behavior deliberately planned by the
state for the whole mass of its people and deliberately forced
upon them J nor, on the best evidence, is it anywhere wholly
due to individual planning to reduce reproduction by birth

106 MAN THE ANIMAL

control. It has occurred and is now occurring among peoples
where effective birth control is but very little practised if at all.
Rather what is going on appears to be a much more complex
biological adjustment or adaptation involving many factors,
both immediate and evident as well as remote and obscure.

Full comprehension of the implications of the present situa-
tion of the world's population, makes it seem to the biologist
that the adaptive regulatory processes demanded will probably
be the greatest and most far-reaching that the human species
has ever so far had to undertake in its evolutionary history.
Those required during the glaciation of the greater portion of
the northern hemisphere seem insignificant by comparison. For,
in truth, as was so ably shown by Prof. H. L. Hawkins two
years ago in his brilliant address as Chairman of the Section on
Geology of the British Association for the Advancement of
Science, the position of man as a species presents today an ex-
traordinary similarity to that displayed by many others in the
paleontological record just prior to their disappearance from
the cosmic scheme of things. The case cannot be better presented
than in his own words, though the quotation must necessarily
be too brief to do justice to the original exposition:

"All of those brave civilisations and empires of which we
have records seem to have shown a succession of similar histories.
They have risen from obscurity through possession of successful
attributes, and have reached the peak of their power only to
pass it.

"Until comparatively recently, there has been a persistent
proportion of ^backward' types, unaffected by the civilising
influence of the progressive powers. These have remained to
provide a new upstart when the current one had crashed. To-day
there are few races of this kind left j almost all of mankind has
encountered civilisation and either perished or been transmuted.
The fatal complexity of civilisation grips the whole species,
crushing it into unity.

"The specific causes of the collapse of once dominant races
are doubtless varied j but there is general agreement that one

THE NUMBERS OF MEN 107

universal factor in disintegration is complexity, an aspect of
over-specialisation.

"The correspondence between this state of affairs and the
morphogenetic trends in other races of animals is so close that
it needs no elaboration. Those who deny that human institutions
are subject to the laws of organic evolution know either no
history or no Palaeontology.

"There is no doubt of man's ability to become the most suc-
cessful type of animal that has ever existed j but the reward of
success in that direction is death."

This cogent statement of the case by a paleontologist distils
to three essentials, in the view of the human biologist: (a) ex-
cessive specialization, to the end of (b) altering enormously the
balance of nature in directions and ways thought by man to be
to his immediate advantage, which in turn (c) has permitted and
encouraged an enormous growth of population, entirely dis-
proportionate in magnitude and rapidity. On the existing record,
as Hawkins points out, no species has ever yet been able, in the
long history of life on the earth, to adapt itself swiftly and
skilfully enough to survive this combination of circumstances.
Whether mankind will or not lies in the lap of the future. The
problem presented is of a sort that statesmen, for the most part,
are by their own natures and aptitudes, by their training, and
in truth by the very nature- of their business, quite unable to
envisage or understand, and still less able to do anything effec-
tive about. Some philosophers and men of science understand
the problem well enough, but lack the power of a Caesar or the
persuasiveness of a Pied Piper to lead mankind to a solution,
even if they knew just the road to take to a practical way out.
So, on the whole, man's only chance of coming successfully
through the ghastly mess he is plainly in for, would seem to lie,
for what it may prove to be worth when put to the supreme test,
in the fact that he has shown himself on occasions to possess
somewhat greater innate powers of adaptability than any other
organism ever known.

Leciure V

PATTERNS FOR LIVING TOGETHER

I

In the preceding lectures in this series it has repeatedly ap-
peared that a set of problems of great insistence and of major
intrinsic difficulty and complexity has confronted man in his
attempts to bring order into the business of his collective living.
These problems exist, and get steadily more difficult, because
there are so many people trying to live together and to get their
livings in a spatially limited universe. Man is definitely and con-
siderably handicapped in his struggles with these problems by
the fact that he is a mammal and heavily loaded down with a
lot of baggage entailed by that zoological affinity. It is essential
baggage, but troublesome rather than helpful in working out
techniques for living together. For mammals as a class are not
naturally strong on sociality. Their innate tendencies are much
more towards the side of rugged individualism. In consequence
such degrees of sociality as they have developed, including even
the human, have always been in the nature of a compromise
between their natural instincts individually to mind their own
business and fend for themselves, and the necessity to work
together imposed by numbers in relation to territory.

This conflict of interests is an inherent element of all sociality,
as the biologist sees the matter. The organism living in social
relations finds itself always struggling to play a double role —
to be at once both a soloist expressing its own personal indi-
viduality and at the same time the humble member of a chorus
constrained to blend his tune harmoniously with those of the

108

PATTERNS FOR LIVING TOGETHER 109

others composing the social group. This is not an easy thing
to do. But it is essentially what sociality demands. The group
may, as a group, do things that are distasteful to every single
individual in it, and against his individual interest considered
fer se. For example, it is easily conceivable that a nation may
decide by popular vote to engage in war, even though each
person in that nation has, as an individual, no appetite whatever
for either killing or being killed. So it is that at the mammalian-
human level there always has to be a compromise — a balancing
between individual and communal interests, strivings, and goods
— rather than the sort of whole-hearted and self-eliminating
espousal of communal group interests to the exclusion of all
other considerations that would be ideal from a purely social
point of view. This kind of complete 100-percent sociality has
never been achieved by mammals. Their social structures always
have in them considerable gaps left open for individual self-
determination — for minding one's own business as well as the
communal affairs. Even such extreme social organizations as
those of Soviet Russia and Nazi Germany have a niche or two
carefully left in them that will permit the possibility for the
individual to rise and shine as Fuhrer or Chief Commissar.
Reflection on the matter leads to the conclusion that one of the
most fundamentally distinctive characteristics of mammalian
sociality, whether it be of rodents, ruminants, carnivores, or
men, is its unfailingly included concept of leadership by some-
body. That somebody may be an individual or a group. It does
not matter which in the underlying philosophy. But, as anyone
will perceive who makes the attempt, it is extremely difficult
for us to think of a form of social organization of which we could
conceivably be a part which did not involve somewhere, in some
form or other, this concept of leadership.

It is in this respect perhaps more than in any other single one
that mammalian forms of social organization differ from those
that have been evolved by other kinds of living things, and par-
ticularly the social insects, ant, bees, wasps, and termites. In
the sociality of those forms there is literally nothing truly

no MAN THE ANIMAL

corresponding to our concept of leadership. There the social
group itself as a whole constitutes a biological unit. Each indi-
vidual in the group lives its life and makes its contribution to
the communal welfare and interests, not because it is told to do
so by a leader, or by the community as a whole in town-meeting
assembled, but because, and only because, it is its innate, entailed
biological nature so to do. The community is made up of castes
that are differentiated structurally, functionally, and behavior-
istically to do certain things in the common interest. Being so
differentiated they do these things automatically, skilfully, and
unfailingly j without yearnings to alter their station in life,
without strikes or picketing, and without troublesome political
ambitions. Power and influence reside in, and appertain only to
the community as a whole, because the physical and physiological
elements that constitute power are so evenly and minutely di-
vided between the several individuals composing the community
that the very concept itself of power as we understand it disap-
pears. In such a form of social organization there is no vestige
of what we understand as individual opportunity, incentive, or
orginality. The community is socially organized in such a way
as to promote and ensure so far as possible the continued survival
of the group as such and as a biological unit. Whether the indi-
vidual survives or not is a matter of no community concern
or importance, save in the case of individuals differentiated for
the task of reproduction. The insect plan of social organization,
perhaps wisely, segregates this function to a few individuals in
preference to distributing it uniformly over the whole com-
munity, and then develops a lot of group adaptations to protect
and ensure the survival of these few breeders.

All sociality or social organization is biologically an adaptive
response to stimuli arising out of the difficulties of living to-
gether in a spatially limited universe, as was pointed out in an
earlier lecture. But the primary objective of this adaptation is
fundamentally different in mammalian sociality from what it is
in insect sociality. The basic objective of the former is the sur-

PATTERNS FOR LIVING TOGETHER 1 1 1

vival of the individualy that of the latter the survival of the
community. "Mutual aid" in the mammalian and human
scheme, wherever and insofar as it occurs, is a communal effort
to help individuals as such to survive, not an attempt to keep
the community or the social system going. When the citizens of
Baltimore, somewhat reluctantly and after long delay, decided
to tax themselves to build a city-wide sewer system instead of
individually disposing of their bodily wastes, they were moved
to do this not because they wanted to preserve Baltimore, but
because they finally came to believe that the probability of their
dying of typhoid fever and of their children dying of dysentery
would be lessened as a result of this course of action. Politicians
are well aware of the individualistic element in mammalian
sociality. The ward boss knows that his clients favor the Tam-
many type of socio-political organization for no other important
reason than because it sees that they are shod and fed. Hence
Tammany Hall survives as a social institution. If the Republi-
cans, or the Communists, or anarchists, or Beelzebub himself
shod and fed the customers better than Tammany, their contri-
butions of votes to the "mutual aid" system would be pretty
promptly transferred to helping the continuance of whatever
social instrument did the better shoeing and victualling. It is
as Byron said in Childe Haroldy "Mammon wins his way where
seraphs might despair." On the national scale it will have been
noted that the impassioned pleas for more and more social legis-
lation that are currently dinning in our ears are based on and
aimed at the survival of "underprivileged" individuals, not at
the survival of the American form of government, which is to
say the American pattern of social organization. Nobody calls
the American social system "my friend," or ever will. Nobody
could. It would be completely foreign to the mammalian way of
thought. Those in control of affairs in Russia delude themselves
into believing they are accomplishing the equivalent of this.
But at the same time they are permitting and encouraging indi-
viduals to have savings bank accounts. The truly and exclusively

112 MAN THE ANIMAL

communistic termite society behaves differently. The termite
savings banks have only one customer per bank, the colony. No
individual has an account.

II

Now while the insect patterns of sociality have certain evident
points of superiority over the mammalian patterns, notably in
respect to their much greater stability and efficiency, after all
they are intrinsically different and not well suited to man as he
is constituted at present. Perhaps in the slow passage of time he
may evolve further towards these insect patterns. There are signs
that this may turn out to be his trend. But before going into that
question it will be profitable to examine in some detail the pat-
terns of existing human society.

The technique that man evolved as an adaptive process to
meet the difficulties that arose out of the necessity for living to-
gether in restricted quarters is essentially comprised within the
frame of the system called government by law. This system had
its dim beginnings in evolutionary history at the very inception
of mammalian sociality itself with the biological family — parents
and children constituting a group that must be socially organized
for at least the rather prolonged period of infancy during which
offspring cannot get their own livings. Let us consider for a
moment what the terms law and government really mean. When
individual mammals have to live together friction inevitably
arises. One annoys another, or interferes with it, or damages it.
Whether the individuals are kin to each other makes no differ-
ence; nor does the age distribution of the group, or any other of
its biological characteristics. At bottom the difficulties arise out
of too close and too persistent contiguity. This leads to what we
have called the "collision effect" — mere bumping into each
other, as it were. In the case of the fruitfly DrosofhilUy where
there appears to be no trace of true sociality at all, it has been
possible to show experimentally that as density of population
increases, and by consequence there is an increase in the fre-
quency of interference of individuals with each other, such

PATTERNS FOR LIVING TOGETHER 113

purely physiological matters as individual fecundity and life
duration are adversely affected in quantitatively predictable
proportion to the intensity of the collision effect. Wherever there
is even the beginning of social organization, as in the mamma-
lian family group, the group, as well as its component individu-
als, has an interest and concern in the nuisances that particular
individuals may make of themselves. So there begin to arise
restrictions or taboos that set limits to the permissible behavior of
the individuals. These restrictions in the group interest do not
have to be written down and codified to be real. They exist in
entirely effective form in mammals far below man. Many ex-
amples could be given if there were time. But a simple one will
suffice. Watch a cat playing with a litter of kittens. When a
kitten gets too rough or bites too hard mama promptly punishes
him. The rule that kittens must not bite a member of the group
too hard is quickly learned.

Human laws began in the evolutionary sense as rules of indi-
vidual conduct or behavior, to protect the group from the
nuisances and torts that might be perpetrated by individuals.
Government followed as a group invention having for its pur-
pose to see that the rules were observed. Since no one ever has
been able to think up any practical mechanism to ensure the
observance of the rules except to punish their infraction, punish-
ment became a group function relegated to government. The
social group in which law and government began was the primi-
tive family. The history of Roman law, that corpus juris upon
which the existing jurisprudence of all civilized peoples is based
and modeled, in a foreshortened and epitomized way throws
light on the essentials of the evolutionary history of all law and
government. The stages are clearly evident in the following
passage quoted from Greenridge's Historical Introduction to
the fourth edition of Edward Poste's classic Gai Institutiones or
Institutes of Roman Law by Galus (Oxford, Clarendon Press,
1904): "The fact that the primitive Roman State was in many
ways conditioned by its clan organization seems to be certain.
As the State grew stronger, it substituted the Family for the

114 MAN THE ANIMAL

Clan. Between the two there is only a diflference of degree. The
Family (Familia) is the aggregate of the members of a house-
hold under a common head, the Paterfamilias j whereas the Gens
is the aggregate of all individuals who bear a common name
and who, therefore, if their ancestory could be traced in the male
line through all its stages, would be found to be the descendants
of some ultimate common ancestor. But the Familia is a far
smaller, and therefore a far less powerful, unit than the Gens.
It cannot so effectively dominate the State or impede its activi-
ties. Again, the heads of families are many in number j the
heads of the Gentes (who must have existed at the time when
the Gens was the important unit) were necessarily few. The
State which deals with families deals with a multitude of indi-
viduals, not with an oligarchy representing the interests of a
number of corporations. The conception of individual rights, in
their modern sense, was, it is true, never fully recognized in
Roman Private Law. It was impeded by the Patria Potestas —
the life-long power of the father over the son. But much was
ultimately done to lessen the rigour of this patriarchal rulej
and the principles of Roman Law were finally extended to
races which knew nothing of the Patria Potestas. This law ulti-
mately gave the most perfect expression hitherto witnessed by
the world of rights which were both universal and individual.
The existence of the Empire gave Rome the power, possessed in
as high a degree by no other State, of dealing with the individual
on universal lines, because she was not hampered by the barriers
between man and man thrown up by separate national institu-
tions."

We see from this how the laws of nations grew out of the
rules for family conduct administered by the head of the family
acting as governor.

It has already been pointed out that the rules for behavior that
later developed into laws as we understand them originated as
group adaptations, which is to say derived their sanctions from
the group attitudes that represent the beginnings of sociality.
This fact cannot be too strongly emphasized, because it is of the

PATTERNS FOR LIVING TOGETHER 115

utmost importance to a clear and critical analysis and under-
standing of theories of government. Another, and funda-
mentally different view of the essential origin of law rather
widely prevailed in the early part of the nineteenth century.
It is historically associated with the name of John Austin, the
English jurist, who first propounded it in his famous Province
of Jurisprudence Determined (1832). He was one of the
founders of University College, London, and its first professor
of jurisprudence. In his first class was John Stuart Mill, who
disagreed in toto with Austin's views on political subjects, but
said of him after his death that he had been the man "to whom
he (Mill) had been intellectually and morally most indebted."
Austin's view, in essence, was that all laws properly so-called
are commands addressed by a human superior to a human in-
ferior, and that the system or institution of government by law
evolved from this basis.

Naturally and obviously this is a position with which no stu-
dent of animal behavior could be expected wholly to agree.
He would quite willingly admit that many laws were, and are,
stated verbally in the form of commands, but that fact seems
to him to be of only rhetorical importance. What the student of
behavior dislikes is the implication of Austin's argument, of
which he was fully aware and accepted, that the whole system of
government by law came into being because a few individuals
were created superior, and a great many inferior, and that the
former governed the latter by commanding them to do, or not to
do, certain things. Such a view is repugnant to the biologist be-
cause it so completely neglects the evolutionary background and
basis of human behavior. Mammalian social behavior is not of
the pattern implicit in Austin's^ formulation. Proof of this is
abundant, for example, in Eraser Darling's important study
A Herd of Red Deer^ already quoted in these lectures. Herd
leaders are not commanders. They function much more as
special sense organs for the group, that is the herd. They watch
and listen for the group, while the other members tend to the
other businesses of life. The group reactions of the herd are

116 MAN THE ANIMAL

not responses to commands, but rather group reflexes set off by
stimuli transmitted through the leader acting as sensory receptor
for the group.

Austin's theory no longer enjoys quite the prestige it once did,
either in or out of the legal profession. The development of
sociology, and particularly the points of view growing out of
what may perhaps be fairly called the natural history type of
approach to the problem of sociality exemplified at its highest
level in the work of William Graham Sumner, have been major
factors in diminishing general esteem for Austin's closely
reasoned, but heavily a frioriy logical treatment of what is, after
all, a biological problem at bottom. There clings to it an odor of
scholasticism that is not in the present mode. At the same time
it must be said that in overt or concealed form Austin's main
thesis constantly bobs up in theoretical discussions of govern-
ment, politics, and social progress, and particularly in connec-
tion with "isms" of one sort or another.

Austin's analysis of jurisprudence was thoroughly and pene-
tratingly criticised about a half century after its publication by
Sir Henry Maine, in his Early History of Institutions (1875).
Only one small portion of Maine's interesting discussion can be
quoted here, but that little must be, because of the important
implications for human biology embodied in its last sentence.
The whole quotation is an example or illustration brought for-
ward by Sir Henry to show that the most despotic sort of govern-
ment conceivable need contain none of the "command" element
postulated by Austin. "My instance," he said, "is the Indian
province called the Punjaub, the country of the Five Rivers, in
the state in which it was for about a quarter of a century before
its annexation to the British Indian Empire. After passing
through every conceivable phase of anarchy and dormant an-
archy, it fell under the tolerably consolidated dominion of a
half-military half-religious oligarchy known as the Sikhs. The
Sikhs themselves were afterwards reduced to subjection by a
single chieftain belonging to their order, Runjeet Singh. At first
sight there could be no more perfect embodiment than Runjeet

PATTERNS FOR LIVING TOGETHER 117

Singh of sovereignty as conceived by Austin. He was absolutely
despotic. Except occasionally on his wild frontier he kept the
most perfect order. He could have commanded anything j the
smallest disobedience to his commands would have been fol-
lowed by death or mutilation j and this was perfectly well known
to the enormous majority of his subjects. Yet I doubt whether
once in all his life he issued a command which Austin would call
a law. He took as his revenue a prodigious share of the produce
of the soil. He harried villages which recalcitrated at his exac-
tions, and he executed great numbers of men. He levied great
armies j he had all material of power, and he exercised it in
various ways. But he never made a law. The rules which regu-
lated the lives of his subjects were derived from their im-
memorial usages, and those rules were administered by domestic
tribunals in families or village communities — that is, in groups
no larger or little larger than those to which the application of
Austin's principles cannot be effected on his own admission
without absurdity."

It is just such "rules derived from immemorial usage" that
constitute the primitive pattern and foundation of all social
organization, and also of enduring government. But obviously
as the numbers of men increased, and the average distance apart
of human beings from each other got steadily smaller, the whole
business of living became more complicated. There had to be
more and more rules. The rules got steadily more complicated
and difficult to administer, until now we have reached a situation
in which not only such avowed dictators as Mussolini and Hitler,
but even our own Thurman W. Arnold, professor of law in Yale
University — an institution steeped in the authentic juices of
liberty if ever there was one — advocate as the ideal government
one by men instead of one by principles. There could be no
franker return to the position of John Austin, nor more convinc-
ing evidence that old patterns of human sociality solidly
grounded in mammalian biology have gone sadly awry as the
difficulties and complexities of living together have grown along
with the stupendous increases in population density that have

118 MAN THE ANIMAL

occurred. Under such circumstances an individual in temporary
possession of political power always wants to "command," and
to be freed from the restraints imposed on his will and fancy
by laws based upon the "immemorial usages" of the group. To
get rid of these irksome hindrances he endeavors to take over
completely, and as a purely personal prerogative and appanage,
the legislative and judicial functions of the social organization.
If the attempt succeeds what appears on the surface to be great
efficiency of government temporarily results. But the situation
is ephemeral. It is just as true now as it was a century and a
half ago, when the Great Pontihcator told his friend General
Oglethorpe about it, that "The more contracted power is, the
more easily it is destroyed. A country governed by a despot is
an inverted cone."

Ill

When we have seen that rules and then laws came into the
primitive picture of free mammalian behavior from the necessity
imposed by sociality, it must always be remembered that it was
necessity rather than desire that brought them in. The natural
state of living things is the most complete freedom and liberty
attainable within the frame of the physical environment. Any
and all restrictions on this natural freedom are inherently irk-
some. This fact has always constituted a real and serious diffi-
culty in the making of workable and acceptable rules and laws.
Jeremy Bentham was profoundly right when he said (The
Theory of Legislation, Chap. X): "It is with government as
with medicine j its only business is the choice of evils. Every law
is an evil, for every law is an infraction of liberty. Government,
I repeat it, has but the choice of evils. In making that choice,
what ought to be the object of the legislator? He ought to be
certain of two things: 1st, that in every case the acts which he
undertakes to prevent are really evils j and, 2nd, that these
evils are greater than those which he employs to prevent them.

"He has then two things to note — the evil of the offence, and
the evil of the lawj the evil of the malady, and the evil of the
remedy.

PATTERNS FOR LIVING TOGETHER 119

"An evil seldom comes alone. A portion of evil can hardly
fall upon an individual, without spreading on every side, as from
a centre. As it spreads, it takes different forms. We see an evil of
one kind coming out of an evil of another kindj we even see
evil coming out of good, and good out of evil. It is important
to know and to distinguish all these kinds of evil, for in this the
very essence of legislation consists."

It is a major tragedy of the world today that this distinction
so wisely urged by Bentham has been so completely forgotten.
The souls and bodies of millions of innocent and harmless
human beings are being tortured because self-righteous and self-
seeking men in temporary possession of power ruthlessly and
contemptuously disregard the fact that all regimentation,
whether it be by law or not, is an evil in itself. And this fact is
in no smallest degree altered by asseverations of nobility of
purpose.

The practical difficulty in framing a working pattern of human
sociality has always been, and probably will continue to be for
a long time in the future, the achievement of a satisfactory steady
state of equilibrium between what is good from the standpoint
of the group on the one hand, and what is evil from the stand-
point of the individual on the other hand. Compromise is the
only possible way of dealing with such an issue. Because it is
gives the reasons why law and government have always been
compromises in their essential nature. If the pattern is formed
solely in the interest of either the group or the individual it
has little stability or power to survive.

The actual machinery of operation of government and rule-
making, the basic social organization, has exhibited in all human
history only two really different fatterns. One of these is the
autocratic, oligarchic pattern, the other the democratic. The
difference between them in theory and in fact — whenever it has
seemed worth while to translate the theory into fact — is that
in the one case the laws and government are made and adminis-
tered by a few individuals in the group without let, hindrance,
or advice from the rest of the group ; while in the other case all
the individuals in the group have a direct first-hand share in the

120 MAN THE ANIMAL

fashioning of the pattern of their sociality. The autocratic pattern
stems evolutionary from the patriarchal or matriarchal family
sociality. The democratic pattern was a slower growth that came
to full flower in human society as men progressed in intelligence
and power to reason, and in consequence developed the desire to
affirm the full essence of their being. The individualistic way
of life is a basic characteristic of the mammalian stem. To mould
it into practical consilience with the necessity for social organiza-
tion was a long, slow, and painful process. Actually the concept
that all men should have an equal share in making the group
pattern of law and government remained, with some exceptions,
largely a negative one so far as action was concerned until the
seventeenth century, though the abstract idea was much older.
Aristotle was perfectly familiar with it, and rightly held that its
denial was the most potent cause of revolutions.

Actually the setting up and maintenance of an autocratic or
oligarchic form of government, as well as of any other form,
can happen only with the "consent of the governed," as the old
cliche has it. But there are two ways in which this consent can
be got. These are either through intimidation maintained by
force, or by voluntary agreement of the demos. Historically
and statistically the former technique has been by far the more
usual one, frequently camouflaged and sugar-coated, but not
less real underneath. The present autocratic dictatorships in
Europe, as everyone knows, insist loudly that they rest on the
voluntary consent of the people, but a lot of purging with
castor oil, gunpowder, and other even less pleasant pharmaceu-
ticals seems to be required to maintain such semblance of sweet-
ness and light as exists in the business. And the techniques of
the elections by which the popular will is supposed to be ex-
pressed in the dictated countries have their comic aspects, which
we can perhaps the better appreciate because they have such
marked resemblances to the modes open to the Negroes in our
deeper South to manifest their political and social' ideas. In short
Germany, and Italy, and Russia do not appear to ofl^er any real

PATTERNS FOR LIVING TOGETHER 121

exception to the general rule that intimidation is a usual, and
indeed necessary, element in the maintenance of autocratic or
oligarchic patterns of sociality wherever found. But intimidation
by jorce majeure has two fundamental defects as a social agent.
In the first place, with human beings constituted as they are,
it is a lot of trouble to keep up. The despot and his gang get
careless and inattentive, and lax about cracking the whip. The
strain involved in being a pompous bogey-man gets wearisome.
In the second place, fear is a curable and largely self-limited
disease. The steady advance of man's knowledge through science
about how to control and alter to his use and benefit his environ-
ment and the inherently awesome forces of nature, have been
the great curative agents for the fear disease in all its varied
manifestations. Organized religion has learned this lesson well.
The "wrath of God" scares few folks these days. The "might
of rulers" scares them only temporarily. Even that quintes-
sentially timid fellow, the American businessman, seems now
slightly less afraid of Tommy the Cork than he was a while back.
The struggle of man to make his general pattern of sociality —
government by law — a stable, enduring, and satisfactory one has
been long and arduous. It has encountered many difficulties.
But there can be no question, I think, that its spiritual goal
all along the way has been that ideal of democracy well stated
by Harold J. Laski as one that is based on the "notion that the
only way to respond to the wants of the individual is to associate
him with the process of authority. It accepts therefore the old
claim that exclusion from a share in power is also exclusion
from a share in benefit. It regards the rights of man to share
in the results of social life as broadly equal j and it regards differ-
ences of treatment as justifiable only in so far as they can be
shown to be directly relevant to the common good." This goal
has never yet been wholly achieved and stabilized anywhere.
But with many waverings and setbacks mankind has moved
forward toward it. And there are still those who like to think
that Nicholas Murray Butler was right when he said thirty

122 MAN THE ANIMAL

years ago: "The future of this nation, as the future of the world,
is bound up with the hope of a true democracy that builds itself
on liberty."

IV

But is this going to be the path of the future evolution of
human sociality? Or is it going always to be merely the silly sort
of abstract ideal symbolizing what does not really exist, that
cynical pseudo-Machiavellians say it is and always has been?
Being acutely conscious that "the coasts of history are strewn
with the wrecks of predictions launched by historians and phi-
losophers," as Lord Bryce once said, I have no present intention
of cracking a bottle of champagne on the prow of a prophecy.
But I should like to discuss briefly some of the difficulties and
possibilities of the case. Let the discussion start with a question:
Why is it that the adoption and practical operation of the idea
of democracy has encountered so many difficulties, when it has
all along enjoyed the esteem and approval not alone of philoso-
phers, but of sensible men almost universally? The answer to
this question seems to me to be bound up with certain funda-
mental biological considerations that have already been discussed
in these lectures but without specific application to the present
problem. The first and most important of these is that men vary,
and widely, in their capacities and talents to get a living as well
as in their opportunities. A primary function of all social organi-
zation is to expand and so far as possible equalize the opportuni-
ties for all individuals in the group to get their livings. In
particular it is a basic tenet of the philosophy of democracy to
do this. But no conceivable amount or kind of organization is
ever going to equalize the innate differences between men in
capacity, ability, or talent. Social theories and patterns of or-
ganization may categorically deny the existence of such differ-
ences, or may seek to smother and overwhelm them by systems
that give equal rewards for extremely unequal services or per-
formance of whatever sort. But this is mass self-delusion, un-
worthy of grown men. The real biological fact is that some men

PATTERNS FOR LIVING TOGETHER 123

are both better animals and better men than others. And in any
form of social organization, or in any way of life that does not
by force prevent it, the better men will tend on the average to
get the greater and better rewards for their efforts. This was
just as true in the hunting stage of culture as it is today in
industrial Detroit. An inevitable consequence is the development
of economic inequalities. The innately abler individuals do
better than just get their livings. They accumulate wealth.
There is nothing in this inherently baneful or anti-social. It is
not more sinister for men so to behave than it is for squirrels.
In fact it is just a normal biological process for both, an effort
to make continued survival more certain.

But in the course of its development there has gradually, and
as to its successive stages almost imperceptibly, been added to the
political philosophy of democracy a new element that demands
"a close economic equality on the ground that the benefits a
man can obtain from the social process are, at least approximately
and in general, a function of his power of effective demand,
which in turn depends on the property he owns," to use Laski's
phraseology. It is held that the theory of democracy must
necessarily be hostile to everything in the nature of privilege
growing out of economic differences between individuals, and
that liberty must be contingent upon, and constrained within,
a framework of economic equality. The logical mischief inherent
in this doctrine is evident as soon as it is stated. Any sort of
constraint is essentially repugnant to the concepts of liberty and
freedom. Procrustes building uniform beds to fit only the
economically short or medium-statured, and sawing off the feet
of the economically long-legged to make them conform to the
beds, is still engaged in an inhumane as well as unbiological
pursuit. If biology and history have any validity at all it is
certain that this technique will never achieve an enduring solu-
tion of the problem of living together. Whether the scheme be
labelled communism or democracy, or whether it be operated
by dictatorship or through a majority of popular votes, it in-
herently lacks survival value, simply because all men are not

124 MAN THE ANIMAL

equal in natural endowments. The attempts to extend the
principle of democracy beyond group rule-making, which in
the mammalian pattern of sociality is in biological fact a group
function, so that it shall also include, and operate in respect of
getting a living has not added to the acceptability or the stability
of democracy as a social pattern. In the basic mammalian sociality
getting a living is an individual function, and not a group func-
tion as it is in the termite pattern.

There would seem to be two possible alternative trends of
man's further bio-social evolution that might conceivably be
followed, provided he succeeds in surviving as a species. In this
apparently elliptical statement is intended to be implicit the
truism that man himself plays an important and conscious part
in determining the course of his own social evolution, and that
there are discernible now only two suggestions of possible future
trends that seem to have a sufficient element of probability in
them to be worth discussing. One of these that is at least
theoretically possible, even if necessarily slow in practical ac-
complishment, would be by breeding out the innate differences
that now exist between men and making them into a uniform
lot except for such caste differentiations as might seem desirable
to perpetuate, or might naturally evolve, in the interest of group
efficiency solely. Such a process would eradicate all significant
individual differences within each caste. Individual incentives
and strivings would disappear, and also the social troubles they
always produce. The process might conceivably be hastened, in
the manner suggested in Brave New World, by conditioning the
young from the moment of fertilization on for group conformity
in the long period while genetic differences were being elimi-
nated by breeding. In the end getting rid of differences would re-
sult in the human equivalent of the termite pattern of sociality.
All men then would be truly equal, within the caste, and eco-
nomically and socially equal within the total group, the colony,
or state, or world. In cold fact this may be precisely the present
trend of human evolution. We are here and now breeding out
the innate differences between men, and at an accelerating rate.

PATTERNS FOR LIVING TOGETHER 125

The genes that condition human characteristics are being more
uniformly and evenly distributed over the whole of mankind.
Perhaps we may all be something like happy little termites yet.
But on the whole it seems unlikely that the process will ever
continue to an end point involving such colossal biological altera-
tions as would be necessary to change our pattern of sociality com-
pletely over to the termite pattern.

The other evolutionary trend that may be envisaged demands
no such fundamental biological reconstruction. It contemplates
instead only the continued and more intelligent development
and application of the social process itself. We have seen in an
earlier lecture that ever since his emergence as a distinct form
man has steadily progressed in devising new and always easier
ways of getting his living. This has come about through ever in-
creasing control and utilization of natural resources, dependent
in turn upon the steady advance of scientific knowledge. It
seems probable that if scientific knowledge and discovery con-
tinue to advance, and there is no presently discernible reason
why they should not, the consequences in increased aggregate
ease of getting mankind's collective living that have followed
in the past will continue to follow in the future. In other words
there would appear to be no indication now of even a beginning
of the operation of the principle of diminishing returns in the
sphere of the application to useful ends of scientific discovery and
developments. If science does continue to advance and extend
man's power to utilize natural resources and forces, the inevitable
consequence will be a general condition of progressive plenty.
Many thoughtful persons are of the opinion that we are at this
moment definitely and measurably already in that condition,
and certainly a rather convincing case can be made that this is at
least partially so. But granting for the sake of the argument that
we are in fact already in an age of plenty, it is evident that there
is the widest diversity of opinion as to how the maximum of
social benefit is to be derived from that situation. Scientific
men, who themselves constitute the group responsible for the
condition of plenty in so far as it exists, are no more homo-

126 MAN THE ANIMAL

geneous or helpful than any other group in their opinions about
how social advantage is to be taken of easier methods of getting
the collective living. Generally opinion regarding the problem
is saturated with emotion and sentiment, and that in great part
accounts for its wide diversity. Propaganda is substituted for
rational analysis, and only tiresome confusion results.

Certain objective realities that exist now, however, have
bearing on the alterations of the social pattern that may occur.
The first and most important of these is the high average density
of world population. Maximum social benefit will never accrue
from a condition of plenty, if population is always maintained at
a level where in actual ^practice it presses close upon the then
existing possibilities of bare subsistence. The average individual
enjoyment of plenty will be greater and keener if there are
fewer individuals to divide it among. There is at the present
moment an almost universal tendency to reduce the total popu-
lation of the world through the reduction of human fertility.
This tendency is being accelerated by the ever wider spread of
the practice of more and more effective techniques of contracep-
tion. There is good reason to suppose that within a century or
less knowledge of such techniques will be nearly or quite uni-
versally disseminated. Probably within that time such techniques
will be taught universally in the schools in all civilized countries,
as they now are or very shortly will be in Sweden. The prev-
alent idea that this will result in extinction by depopulation
does not seem likely to the student of mammalian biology. What
appears infinitely more probable is that mankind will use
contraception as one agent of self-regulation of the total popu-
lation to a level where the maximum of social benefits accruing
from a condition of plenty may be enjoyed.

Secondly, there is a definitely increasing aggregate conscious-
ness that the social burden of the biologically unfit, degenerate
and worthless portions of humanity is becoming intolerable,
and that their further breeding will have to be stopped. Sensi-
ble men are not likely indefinitely to permit a great part of the
plenty that might be enjoyed by the fit wasted on a growing

PATTERNS FOR LIVING TOGETHER 127

horde of sorry specimens that any intelligent breeder, or nature
itself if permitted, would promptly eliminate as of no biological
worth. The eugenists are grappling with the problem of devis-
ing adequate and practical ways of accomplishing this result.
They have not solved it yet. But there is every reason to suppose
that in another century or so great and real progress will have
been made in this direction.

Suppose we now let our imaginations jump ahead that century
and envisage a world population of an average density of per-
haps 30 per square mile of land area instead of the present 41,
and a population rid of a substantial part of the burden of the
unfit, living in a world of a vastly greater plenty than anything
we now know or can intelligently imagine, as a result of the
intervening progress of science. What pattern of government
by law would, in such a state of affairs, conduce to the maximum
of social benefit practically achievable? This question can be
answered only with an opinion j and by me, if I am to be sensi-
ble and honest, only with my opinion. I present it, not because
it has any particular intrinsic importance, but because it is a
convenient way to make one final point that I regard as
significant.

The pattern of government by law that I think would be
adequate to meet the postulated premises would be one in which
all ultimate governmental power rested in and was equally dis-
tributed among all the people composing the group. As one of
its two main objectives it would preserve, so far as possible,
the innate biological differences between men. I mean this in
the broadest sense of the word biological, to include abilities,
talents, and opinions as well as purely anatomical and physiolog-
ical traits. But it would not merely strive to preserve innate
differences. It would also actively and zealously encourage and
promote the freest possible expression of those differences in
every aspect of life, insofar as such expression was consilient with
the equal distribution of the privilege to all. Specifically it would
encourage individual incentive and striving in the economic and
every other field of activity, and both permit and encourage

128 MAN THE ANIMAL

different rewards proportioned to differences in abilities and
skills. In conformity with the basic mammalian pattern of
sociality it would give opportunity and encouragement to the
superior individual to rise to leadership. Its second main ob-
jective would be to make such rules as would strictly limit as
to amount and degree and as to duration the fower that any
man or sub-group of men could have over the souls or bodies or
lives of their fellows, whether political power, economic, social,
or any other kind. It would do this at whatever cost of group
efficiency, either alleged or real, that might be entailed. It would
do this on the ground that freedom to exercise concentrated
power is the one kind of liberty that no man or no limited group
of men can be entrusted withj there is still too much of the
beast left in his- make-up. Concentration of power to control and
coerce men is bad in itself, always and everywhere, and without
the slightest relation to whether it is used to accomplish ends
which either you or I or anybody else regard as good or beauti-
ful or wise. Because there would be no concentration of power
in this social pattern there would be no economic monopolies,
no great trusts, no holding companies. Some men would be
richer than others, but no man would be either inordinately
rich or terribly poor. With all ancillary aids to the acquisition
and retention of power outlawed, no man could exercise more
influence over the lives of his fellows than what could tempo-
rarily be derived from his true innate superiority as a man. In
guarantees of liberty, opportunity, and strictly limited concen-
tration of power, coupled with a general condition of plenty,
there is reason to hope and to believe that real social security
would reside.