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WHAT SCIENCE REALLY MEANS 



By the same Authors 
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WHAT SCIENCE REALLY MEANS 

AN EXPLANATION OF THE HISTORY 

AND EMPIRICAL METHOD 

OF GENERAL SCIENCE 



BY 

JULIUS W. FRIEND 

AND 

JAMES FEIBLEMAN 



LONDON 

GEORGE ALLEN & UNWIN LTD 
MUSEUM STREET 



FIRST PUBLf"ftED IN IQ37 



All rights reserved 

PRINTED IN GREAT BRITAIN BY 
UNWIN BROTHERS LTD,, WOKING 



CONTENTS 



CHAPTER PAGE 

I THE PROBLEM OF EMPIRICISM n 

Undetermined Meaning of Science n 

Conflicting Definitions of Empiricism 1 3 

The Bias of Scientists 14 

Idealism and Positivism 17 

Rejection, of Both Theories . 1 8 

Science and the Public 21 

Purpose of the Book ' 23 

II THE ORIGINS OF EMPIRICISM 26 

Hellenic Empiricism 26 

Hellenistic Empiricism 30 

Byzantine-Moslem Empiricism 3 5 

Christian-Mediaeval Empiricism 40 

Renaissance Empiricism 46 

III THE DEVELOPMENT OF EMPIRICISM 52 

Seventeenth-Century Empiricism 52 

Eighteenth-Century Empiricism 57 

Nineteenth-Century Empiricism 61 

Twlntieth-Century Empiricism 65 

Empiricism Misunderstood . 69 

IV MODERN MISCONCEPTIONS OF EMPIRICISM 75 

From Hume to Cornte 75 

Early Formulations of Positivism 77 

Mach, Poincar, Pearson 79 

The Mentalist View 83 

The Logical Positivist View 85 

The Operationalist View 91 

The Realist View 96 



8 WHAT SCIENCE REALLY MEANS 

CHAPTER PAGE 

V NATURE OF THE FIELD OF SCIENTIFIC 

INVESTIGATION 101 

With What is the Controversy Concerned ? 101 

The Inquiry into Scientific Objects 106 

Scientific Objects are Functions 1 1 1 

Functions in the Various Sciences 116 

Are Scientific Objects Empirical? 119 

VI THE METHOD OF EMPIRICISM 122 

The Brute Faith in the Given 122 

Abstract Character of Common Experience 125 

Procedure of Scientific Abstraction 128 

The Principle of Economy 131 

Relativity of Empiricism 134 

All Sciences Experimental 137 
The Experimental Sciences of Logic, Mathematics, 

and Metaphysics 141 

VII THE LOGIC OF SCIENCE 146 

Induction and Deduction as Directions 146 

The Logic of Scientific Method 149 

Analysis and Synthesis 154 

Mechanism and Purpose 158 

Deduction versus Imagination 161 

How Science Should Progress 164 

VIII CAUSALITY AND PROBABILITY 168 

Empiricism and Causality 168 

Causality and Continuity 171 

Causality is Non-Temporal 173 

Probability Requires Causality 178 

The Statistical Method and Causality 181 

Probability and Logic 185 



CONTENTS 9 

IAPTER PAGE 

IX THE FUTURE OF SCIENTIFIC EMPIRICISM 190 

Summary of the Argument 190 

Science Must Become Self- A ware 195 

Relation Between Science and Society 198 

Is Social Science Possible ? 202 

The Future of Applied Science 205 

The Future of Theoretical Science 207 

INDEX 213 



WHAT SCIENCE REALLY MEANS 

CHAPTER I 

THE PROBLEM OF EMPIRICISM 

Ulysses has no use for Plato, and the bones of his 
companions are strewn on many a reef and many 
an isle. 

A. N. WHITEHBAD 
UNDETERMINED MEANING OF SCIENCE 

THE modern world, which has lost faith in so many 
causes, still accepts science nearly unchallenged. Science 
to-day occupies the position held by the Roman Church 
in the Middle Ages: as the single great authority in a 
world divided on almost every object of loyalty. The 
tremendous prestige which science enjoys is not unde- 
served. Yet despite the extent of its reclame and the wide 
reach of its practical effects, the genuine understanding of 
its purpose and method remains obscure. The banker and 
the barber share a conviction in the necessity for the con- 
tinuance of scientific research, a conviction which far out- 
runs their comprehension of what research consists of and 
what it hopes to accomplish. 

Still more extraordinary is the fact that most of its 
practitioners, the scientists themselves, share this vague- 
ness of what science is, or at best enlighten it with in- 
tuitive insight. It may seem a strange assertion that those 



12 WHAT SCIENCE REALLY MEANS 

who lead a movement possess no clear idea of what they 
are doing, no definite conception of where they may 
expect it to lead. In short, there does not exist a single 
abstract formulation of scientific method on which all 
scientists agree. 

Until the present, the successful procedure of science 
has only in a very limited sense been a matter of planning, 
and has often resulted from chance discovery and happy 
following of the correct method. Curiously, the early 
scientists who put physical science upon its right path 
did not have to understand fully the philosophy of 
science. Galileo, who led physics to its mathematical 
basis, professed to believe in atomistic mechanism. 
Newton, the great systcmatizer of physics, professed to 
disbelieve in the importance of general theory. Thus far 
this haphazard proceeding, with its cleavage between 
theory and practice, has not prevented profitable dis- 
coveries in the physical sciences, although it has led every 
other would-be scientific endeavour astray. The social 
studies have arrived nowhere as sciences because they 
have followed the explicit creed of physical science. 

The time is over when scientific method can be fol- 
lowed without being explicitly understood. Not only 
will such innocence prove crucial, as it has done in all 
but the physical sciences, but it will also hinder and 
perhaps destroy the progress of physical science itself. 
The abstract understanding of a method may not be an 
absolute necessity at the beginning, but after a certain 
point it becomes indispensable for progress. Abstract 
understanding not only serves as a guide for those who 
have strayed from the true scientific method, but gives 



THE PROBLEM OF EMPIRICISM 13 

reassurance to those who have intuitively anticipated it. 
Science, which has thus far blithely ignored definition, 
to-day finds itself under the necessity of being accurately 
defined. 

CONFLICTING DEFINITIONS OF EMPIRICISM 

All scientists agree that empiricism lies at the base of 
science, and some would even make the terms synony- 
mous. Empiricism is the rock on which the scientific 
faith is built. Not only is this true of the physical sciences, 
but it is also true of those who would ape their method, 
and of those who wish to be 'scientific* in fields which 
are not yet reduced to the condition of science. Yet the 
very term which describes scientific labours is loosely 
used and remains as to definition largely a matter of 
disagreement. 

What does empiricism mean? The following con- 
flicting definitions, which have been drawn more or less 
at random, offer little satisfaction on this score. Aristotle 
employs the terms ' 'empirical" and "historical" as having 
the same meaning. Sir William Hamilton states that "the 
term empirical means simply what belongs to or is the 
product of experience or observation." Whitehead offers 
this illuminating definition of empiricism, "that eternal 
objects tell no tales as to their ingressions." And Bridgman 
states the matter as follows: "empiricism . . . recognizes 
no a priori principles which determine or limit the possi- 
bilities of new experience." 

These definitions, mostly by philosophers, paint a 
picture of confusion, and certainly do not define empiri- 
cism as it is understood by the scientists. On the other 



14 WHAT SCIENCE REALLY MEANS 

hand, if there exists any single and unified definition of 
empiricism upon which scientists in general do agree, we 
have not been able to get them to tell us what it is. 
Clearly no scientist accepts in practice any of the philo- 
sophical definitions, since he is constantly dealing with 
what to him are empirical entities, which are not derived 
solely from sense experience. Metabolism, electro- 
magnetic fields, ionization these are empirical scientific 
entities, yet all are constructions of experience and none 
is altogether presented by mere sensation. 

Whatever else the scientists mean by empiricism, they 
do not mean the limitation of all knowledge to sense 
experience, which philosophical empiricism involves. 
And the fact that they do not accept such a definition is 
evinced by their practice. Nevertheless, this confusion 
between philosophical and scientific empiricism may well 
result in disaster unless it is dissipated. 

THE BIAS OF SCIENTISTS 

Why has there been no abstract understanding securing 
full agreement concerning the aim and method of 
empirical science? The answer must be sought in the 
anti-metaphysical bias of the scientists themselves, a bias 
which arose at the end of the Middle Ages and which 
continues to colour the attitude of scientific men. The 
emphasis away from theory and toward the accumulation 
of indisputable facts of nature, to be learned by observa- 
tion and experiment, precluded any possibility of specu- 
lation concerning true definition. Just as the Middle Ages 
appeared too metaphysical in their cloistered speculation, 
so the ages that followed went to the opposite extreme 



THE PROBLEM OF EMPIRICISM 15 

and laid an implicit prohibition on all speculation. 
Scientists in fighting shy of metaphysics supposed that 
empiricism is not a philosophical affair at all. Their 
premises, though based on a metaphysics, were not 
understood as such, and since those premises were ade- 
quate for the development of natural science up to the 
end of the nineteenth century, the lack of interest in 
philosophy seemed to be pragmatically justified. 

But the old materialistic mechanism which tried to 
present the world in purely tangible form, ruling out all 
else as mental interpretation, was a crude formulation. 
It had to postulate mysterious forces to work on tangible 
matter; it had to conceive so-called secondary qualities, 
such as colour, smell, etc., as unreal. Its very bedrock 
was a belief in an indestructible substance, a world of 
atoms each existing only by virtue of itself under various 
combinations. As a consequence, such combinations were 
not real in the same sense that the atoms were real, but 
merely combinations of real atoms producing different 
appearances. Nevertheless, such a belief was already 
contradicted by many of the facts of the old science. For 
instance, combinations of various atoms were tacitly 
admitted to make different 'substances' in chemistry. No 
chemist would have said that water and peroxide of 
hydrogen are two 'appearances' of real hydrogen and 
oxygen atoms. Thus tacitly it was accepted that dif- 
ferences in combination and organization were at least 
for purposes of manipulation realities. It is fair to con- 
clude that even classical science dealt in non-sensuous 
entities as empirical. 

However, at the end of the nineteenth century science 



16 WHAT SCIENCE REALLY MEANS 

faced a crisis; it became questionable whether the 
scientists had succeeded in dodging interpretation as 
thoroughly as they believed they had. It seems strange 
that they could have overlooked the fact that the doctrine 
of exclusive reliance upon experiment is itself philo- 
sophical no less philosophical for not being formulated 
as such. As has been shown time and again, the theory of 
empiricism is not itself empirically justifiable. Thus un- 
consciously scientists have fastened on to a contradictory 
theory: one that denies the validity of theory. Fortunately 
for the development of science, however, the practice 
has deviated from the theory. Had scientists been mere 
accumulators of facts, science would never have become 
the institutionalized search for truth that it is to-day. 
Even such an assiduous experimenter as the late Pavlov 
was, throughout his long career, advised young scientists 
not to let themselves "become the archivists of facts." 1 

The twentieth century brought about a new state of 
affairs. With the acceptance of the theories of relativity 
and quantum mechanics, the certitude resulting from the 
anti-metaphysical bias of scientists was upset. It became 
clear that the mechanical model of the universe which 
followed the Newtonian conception was no longer 
adequate to take account of all the fresh data. Physical 
scientists were unable to describe their subject-matter in 
picturable terms, and so were half led to accept the 
public estimation of science as a mysterious affair. Still 
reluctant to have recourse overtly to metaphysics, the 
scientists began to talk about first principles in terms of 
science, as though these were part of scientific findings. 
1 Science, vol. 83 (1936), p. 369. 



THE PROBLEM OF EMPIRICISM 17 

And everyone concerned slowly had to admit that not 
only was science returning to philosophy, but also that it 
had never really abandoned it. 

IDEALISM AND POSITIVISM 

Now that science is driven back to search for its meaning 
in philosophy, two schools arise which attempt to define 
the first principles of science: idealism and positivism. 
Popular exponents of the first are Eddington, Jeans, and 
their followers. Their idealism, or perhaps as it is better 
described, mentalism, sets forth in effect that the physical 
world is a construction of the mind upon something 
ultimately unknowable, or that ultimate physical reality 
consists in mathematical thoughts in the mind of God, of 
which human beings know only the appearances. Such 
a subjectivism seems to cut the ground from under 
empiricism, or at best to make that doctrine psycho- 
logical. Plainly, here is a conclusion that scientists refuse 
to accept. It has always been one of the tenets of scientific 
faith that objective agreement is essential to the develop- 
ment of science, and that such agreement must be kept 
free from any psychological opinion. "Mind-spinning" 
is just what the scientists have always been most suspicious 
of. And here is a philosophy which seems to assert that 
all scientific ideas are mind-spun. 

The other school is that of positivism, which enjoys a 
new vogue partly because of its antagonism to the 
idealistic interpretation. This school, headed by Carnap, 
Bridgman, and others, represents the old scientific re- 
vulsion against metaphysics, though itself incurably 
metaphysical. Positivists claim that the reality of scientific 



1 8 WHAT SCIENCE REALLY MEANS 

ideas rests solely upon their demonstrability in operation 
or experiment. They deny causality and substitute in its 
place the observation of the temporal sequence. Here is 
an attempt to escape subjectivism. But since its objectivism 
hangs entirely upon the sense experience and actions of 
the experimenters, it falls back into a subjectivism which 
makes scientific ideas mere shorthand summaries of 
experience. 

The general tendency of the last decade has been to 
follow the positivistic rather than the idealistic interpre- 
tation of science. Scientists lean toward positivism for fear 
of wild and unrestrained theorizing. The attraction of 
positivism for scientists is that it seems to be hard-headed 
and practical, and to avoid metaphysical and mythological 
elements. It seems to draw a very sharp dividing line 
between what is scientific and what is not. This bias 
should not surprise anyone familiar with the history of 
science; nevertheless it is as wrong-headed as idealism. 
That, in fact, positivism suffers from the same defect as 
idealism will be shown later. 

REJECTION OF BOTH THEORIES 

There are many objections which will immediately appeal 
to anyone who considers science according to the 
doctrines of idealism or positivism. The exact con- 
tentions will be examined in later chapters. At present 
we may briefly group a few arguments to show how 
dubious these positions are. 

Is empirical science, which has always prided itself on 
being objective, in that it allows no one man's opinion 
merely by being an opinion to alter the facts, now going 



THE PROBLEM OF EMPIRICISM 19 

to assume that the only objective basis can be opinion? 
Can science be what Bridgman calls it, "my private 
science/' 2 and remain science? In other words, is science 
to be reduced to a psychological matter of consciousness ? 
Does anyone truly believe that the application of mathe- 
matical laws to nature is mental ? In other words, do they 
work because we know of them, or do we not rather 
know of them because they work? Did iron assume 
magnetic properties simultaneously with the discovery 
of its magnetic properties ? 

If we grant the idealist's contention that the photo- 
electric cell and the Wilson cloud chamber are equally 
mental, how can the differences between them be 
accounted for ? Certainly this difference will have to be 
explained in non-psychological terms. Therefore the 
scientific problem from the idealist point of view remains 
just what it was before. To place the observer within the 
field of that which he observes is like making a camera 
an essential part of every picture of Niagara Falls. The 
idealist philosophy is plainly no answer to the much 
sought-for philosophy of empirical science, and the 
scientists are right in their intuitively arrived at decision 
to refuse it. 

The objections to positivism are equally cogent. 
Whatever else empirical science may be, it is certainly 
not positivistic. If it were, new empirical entities would 
never come to light, since everything not already dis- 
covered would remain a theoretical hypothesis. Thus 
science could never have advanced. But ignoring this, 
let us inquire in what way are electrons summaries of 
2 The Nature of Physical Theory, p. 13. 



20 WHAT SCIENCE REALLY MEANS 

anybody's experience ? Are Kepler's laws of planetary 
motion and Balmer's law for the position of lines in the 
hydrogen spectrum altogether products of experience ? 
The whole applicability of mathematical science would 
be negated if scientific laws were merely summaries of 
past happenings. Positivism overlooks the most obvious 
ambition of science: the aim to reach exact predict- 
ability. 

The procedure of science toward the successful unifica- 
tion of physical theory, as when gravitation and inertia 
were enveloped by the theory of relativity, should indi- 
cate that laws cannot be merely statistical summaries, 
and that something more than a mental unification of 
experiments is being reached. The grave objections to 
positivism are enough to suggest that positivism is not 
the required answer to the newly recovered need for a 
philosophy of science. Positivism is more of a danger to 
the future of science than idealism because the former 
has secured more support from the scientists than its 
rival, and indeed just now seems to be the choice wherever 
scientific men feel the need for a philosophy. What the 
positivists have done is to hold on to experimentation, 
and thus as they see it to empiricism, at the cost of 
denying reality to the scientific subject-matter itself. 
They have saved the method only by sacrificing the 
existence of that which the method studies. 

In idealism and positivism there is no objective reality 
to the entities of science. Neither idealism, which would 
refer science to the psychology of consciousness, nor 
positivism, which would refer it to the psychology of 
behaviourism, is adequate to supply an understanding of 



THE PROBLEM OF EMPIRICISM 21 

what empirical science is. The first theory dissolves 
empiricism; the second tries to hold on to it by dis- 
solving everything else. 

SCIENCE AND THE PUBLIC 

The prestige of science is very great even outside 
scientific circles. Thus far the public has not looked to 
science altogether in vain. The tremendous hope invested 
in science is amply justified at least by the physical 
sciences, although to be sure this does not mean that 
the public understands what science is or what it is try- 
ing to do. Rather does the layman look to science to 
announce what reality is. Thus it is not too much to say 
that whichever way the interpretation of science turns 
the popular understanding of reality will follow. Obvi- 
ously, then, what has been said about the bias of the 
scientists in favour of positivism applies with equal force 
to the public. To the popular mind science is an 
agglutinative compendium of facts largely unrelated. 

The form which popular positivism assumes is that of 
placing great faith in seemingly demonstrated facts and 
of distrusting all theory. Its assumption that this procedure 
is the scientific method is well shown by the constant 
appeals in the popular Press, in advertisements, and in 
innumerable arguments where the terms 'science' and 
'scientific* are bandied about as conclusive and irre- 
futable. The fact that the public accepts the contra- 
dictory beliefs that science is altogether concerned with 
final and utterly demonstrable matters of fact, and that 
science is always in process of changing its mind, only 
goes to reinforce the statement that the public knows 



22 WHAT SCIENCE REALLY MEANS 

no explicit formulation of science but implicitly accepts 
positivism. 

The question may be asked as to what difference it 
makes whether the public understands science or not, 
particularly in view of the fact that science has gone 
forward without public understanding. It is true that 
physical scientists have been able to proceed until now 
unmolested, carrying through a rational programme 
within a society which still tries to go on in the old 
irrational manner. But it is already becoming obvious to 
many thoughtful scientists that this condition cannot 
continue indefinitely. We may say that the historical 
career of physical science has so far been promoted by 
good luck. Already, however, there are signs that the 
rear-guard is deserting the scientific vanguard, and that 
science is too far ahead of the main procession of humanity 
and may soon be cut off from the service of supplies. 
For this not to occur, it will be necessary for the public 
to understand at least a little of the aim and methods of 
science. In other words, the public must recognize the 
value of theoretical science as well as the usefulness of 
applied science. 

If some such understanding of science does not reach 
the public, it will no longer continue to have patience 
with anything but immediately practical results. Need it 
be urged that practical results do not come without a 
theoretical background? Continued ignorance on the 
part of the layman may have the social effect of abating 
the development of theoretical science. Thus the clarifi- 
cation of science and scientific method is much more 
than a philosopher's idle speculation, or a theory spun 



THE PROBLEM OF EMPIRICISM 23 

to satisfy the desire of a few specialists to understand 
what they are doing. The need for an understanding and 
clarification of empirical science is not only a practical 
necessity for science proper, but also one for the world 
in general. Science and the public benefit together, or 
neither benefits. 

PURPOSE OF THE BOOK 

We believe it can be shown that the subject-matter of 
science has existence with or without its comprehension 
by the mind, with or without the experiments by which 
it is demonstrated. If empiricism can be shown to have 
reference to an independent system which men can 
discover and follow, but which they do not create either 
by conceiving it or by performing certain operations, 
then scientists need be in no doubt as to the objective 
reality of their entities. In other words, a proper under- 
standing of empiricism would exhibit that the so-called 
'concepts' of science refer to entities which are not con- 
cepts and not operations but independent facts. The 
critical misunderstanding of reality as applying only to 
tangible things is responsible for these two variants of 
mentalism: idealism and positivism. The functions which 
scientists analyse can hardly be called tangible or sensory, 
though observable only in and through things and events 
as processes. Empirical science needs further philosophical 
exposition. 

The main requirement, then, is the definition of the 
aim and method of science, which in turn involves the 
clarification of empiricism. The stubborn and intuitive 
understanding that empiricism must at all costs be pre- 



24 WHAT SCIENCE REALLY MEANS 

served is a virtue of the physical scientists' practice. But 
for this intuition to be rationally justified requires some- 
thing more than mere faith. It deserves an explicit creed. 
The utter exclusion from metaphysics in which science 
thus far has tried to hold itself has been invaded, and 
ostrich tactics will not avail. 

In analysing empirical science as to its aim and method, 
we do not claim the discovery of anything new. On the 
contrary, we are trying to abstract and make clear what 
that aim and method have always been, what they 
should be, and what they must be. In so far as science 
has succeeded during its historical career, it has followed 
a certain method. Therefore we are not concerned with 
the way in which it has proceeded historically, except in 
so far as such an inquiry helps us to learn the way in 
which it should proceed logically. The fact of the manner 
in which scientists have stumbled upon or deliberately 
reasoned their way to the truth must be distinguished 
from the ideal toward which they have aspired only by 
approximation. Whether a child learns arithmetic by 
counting on his fingers or his toes has no effect upon the 
cardinal number series with which he becomes familiar. 
But obviously it is preferable to proceed logically, if only 
because such procedure saves time and energy. The ideal 
method of science is not of necessity the exact one 
followed by any scientist. 

What we are claiming, then, for the clarification of 
the aim and method of empirical science is that whatever 
procedure the scientist may take to arrive at new hypo- 
theses and new facts, he will be able to understand far 
better what he is doing; and in the long run this will 



THE PROBLEM OF EMPIRICISM 25 

unquestionably keep him from wandering too far afield, 
as it will also set his inquiry into fruitful paths. In a word, 
what he has been accomplishing mainly by intuition and 
incomplete understanding should be available to him as 
an abstract formulation. 



CHAPTER II 
THE ORIGINS OF EMPIRICISM 

It is an unwarranted assumption that ancient 
science differed in principle at any point from that 
of to-day. 

W. A. HEIDEL 

IN order to understand the place which empiricism holds 
in the esteem of scientists, as well as to expose the cause 
of the antagonism of science to the speculative reason, it 
will be necessary to give a short sketch of the history of 
empirical science. Only history can show how scientists 
could have made the error of absolutely dividing the 
empirical from the logical. However, no attempt is made 
here to sketch an adequate history of science; all we can 
hope to accomplish in so short a space is to exhibit the 
occasion for the rise of empiricism and to touch on the 
significant points of its development. 

HELLENIC EMPIRICISM 

The history of empirical science is at least as old as re- 
corded cultural history. In Egypt and Babylonia the 
beginnings of the sciences of astronomy, medicine, and 
mechanics were due to speculations upon problems of a 
practical nature. It was necessary to make careful observa- 
tions and to draw inferences from them. But of course 
this early empiricism was neither formulated as a theory 
nor segregated as a practice, but was resorted to along 
with magic, astrology, and other pseudo-sciences. 



THE ORIGINS OF EMPIRICISM 27 

Early Greek empiricism was of this same sort, although 
the Greek nature philosophers were more inclined to be 
sceptical in regard to mythological and magical explana- 
tions. Thales' belief that water is the prime substance was 
an induction which went beyond the verifiable facts, yet 
it was based on the empirical observation of the presence 
of moisture in natural objects. Thales experimented in 
other matters, as when he showed that amber rubbed 
would attract light bodies. 

The statement that the Greeks were not empiricists but 
relied exclusively on reasoning is not true. Anaximander 
observed that the heavens revolve around the pole star. 
And although the name of Pythagoras is associated with 
mystic sciences, such as numerology, he is said to have 
accomplished one of the finest pieces of observation and 
inductive reasoning, which he afterwards deductively 
checked. Noting that the sound of two hammers on 
an anvil were separated by an octave, he weighed the 
hammers to find that the weight of the one was double 
the weight of the other. This experiment was then re- 
peated on the monochord, from which it was found that 
the length of string was likewise proportional. The length 
of string required to produce the concordant notes showed 
the proportions 12 : 8 : 6. 

Alcmaeon of Crotona, a younger contemporary of 
Pythagoras, was likewise an experimenter. He dissected 
animals; discovered the optic nerve; distinguished empty 
veins from those carrying blood, etc. Xenophanes of 
Colophon gave the correct interpretation of fossils. 
Anaxagoras dissected the brain and recognized its lateral 
ventricles; he discovered that fishes breathe through their 



28 WHAT SCIENCE REALLY MEANS 

gills. The Hippocratic Corpus is filled with all sorts of 
examples of careful and minute observation. For instance, 
embryology was studied by opening hen's eggs day by 
day as incubation progressed. Euryphion of Cnidos, 
among other experimental researches, discovered that 
pleurisy is a lung affection. Eudoxus of Cnidos experi- 
mented in astronomy, acoustics, mechanics. Philip of 
Opus explained the rainbow as a phenomenon of re- 
fraction. The observations of Aristotle in zoology are 
famous; e.g. his description of the placental development 
of the dogfish, and of the stomach of ruminants. Aristo- 
xenus and Strato, both members of the Aristotelian 
school, conducted rigorous empirical observations in the 
physical field. 

Enough has been said to show that the Greeks observed 
as well as speculated. But if experimentation was as 
plentiful as our random examples indicate, why was 
Greek science not more fruitful? The reason for the 
failure of Greek science is that observation by itself, like 
speculation by itself, is not sufficient for science. The 
Greeks, it is true, both experimented and speculated, but 
theory and experiment were kept too far apart. Thus 
their experimentation became positivistic and their 
reasoning dogmatic. Aristotle exhibits both errors. At 
times he is an empirical dogmatist (positivist), as when 
he is certain that plants cannot feel "because they are 
composed of earth." 1 and at other times he is a rational 
dogmatist, as when he asserts that just as "the triangle is 
implied by the quadrilateral," so "the nutritive faculty 
[is implied] by the sensitive." 2 

1 On the Soul, III, xiii. 2 Ibid., II, iii. 



THE ORIGINS OF EMPIRICISM 29 

It must be admitted that the general tendency of Greek 
thought militated against the development of empiricism 
as a creed. Unfortunately for the progress of empiricism, 
Greek philosophy in its thorough grasp of the place of 
reason, held experimentation back. There was a prejudice 
in the Greek mind in favour of discovery by deduction 
from principles held, instead of discovery by induction 
from experiment. The world of actuality was derogated 
in the Platonic version to a mere appearance of a divine 
order of Ideas. And thus an intellectual demeaned him- 
self somewhat by abandoning pure thought for vulgar 
experimentation. " Science," said Aristotle, ' 'should con- 
cern itself with eternal objects immutable and pure." 
Socrates asserted that the subject-matter of physics is 
'Vain, useless and perilous." 

This whole attitude unquestionably held back science, 
even though remarkable beginnings show the wide 
interest of the Greeks in empiricism. "Theory and 
practice do not always progress pari passu," 3 and the 
Greeks understood at least the difference between how 
science progresses and how it should progress. 4 Greek 
theory and practice, however, broke away from each 
other, and when Greek science was carried into Christian 
Europe, it was the dogmatic categorization and reliance 
on deductions from unproved assumptions which were 
preserved; its empirical basis was forgotten. The bias of 
this heritage should be carefully noted, because it was 
the revulsion against the dogmatic aspect of Greek 
science which led the early empiricists of Latindom to 

8 W. A. Heidel, The Heroic Age of Science, p. 95. 
4 Hippocrates, De Prisca Medidna, 12 (III, 596 f., L). 



30 WHAT SCIENCE REALLY MEANS 

rediscover empiricism, but with the difference of opposing 
it to the speculative reason. 

HELLENISTIC EMPIRICISM 

Aristotle died in 322 B.C., and the Hellenistic Age of 
Greek expansion which followed saw a greater develop- 
ment of the practice of empiricism. Despite the weight 
of Aristotle's authority this new age was to distinguish 
itself principally in experimental science. Why was 
empiricism more widely practised in the civilization 
which centred around Alexandria than in the one which 
centred around Athens ? While it is undeniable that the 
new era had a respect approaching awe for the older 
Greeks, it is also true that this very fact made the Hel- 
lenistic Greeks commentators and analysers rather than 
innovators. In literature this produced grammarians and 
rhetoricians, but in the study of natural objects it brought 
about the beginnings of a thoroughgoing science by 
focusing attention on analysis, and a fortiori on experi- 
ment. Moreover, Aristotle had excluded the mathe- 
matical method from philosophy, and as a consequence 
it went by default to science. This isolation of science 
from philosophy proved pro tern, a good thing, though 
in the end it corrupted both. Philosophy became more 
concerned with the unearthly and the mystical, and 
science became more positivistic. 

But in the beginning of this period the return of 
science from remote contemplation to practical research 
proved fecund. Theophrastus of Lesbos wrote describing 
minerals and plants, of which he certainly had experi- 
mental knowledge. Dicaearchus of Messina noted the 



THE ORIGINS OF EMPIRICISM 31 

influence of the sun upon the tides. Herophilus and 
Erasistratus rejected all references to the occult and in- 
sisted upon natural causes. They practised dissection and, 
it is said, vivisection, thus improving enormously the 
knowledge of such organs and functions as liver, salivary 
glands, brain, the relation of vascular to nervous systems, 
and the relation of respiratory to arterial systems. Aris- 
tarchus of Samos, who arrived at a heliocentric theory, 
worked the results of his observations into geometrical 
form. Note the difference between the use of mathe- 
matics here and in Plato's astronomy: the first is based 
on reasoning from observation of what is, the second on 
reasoning from what (it seemed) ought to be. Era- 
tosthenes' famous experiment in calculating the size of 
the earth by actual observation of the latitudes and dis- 
tances of Syene and Meroe failed only by fifty miles of 
die true value of the diameter. 

Archimedes was the greatest Hellenistic scientist and 
one of the foremost experimental scientists of all times. 
He had, moreover, a clear abstract understanding of 
scientific method. He wrote: 

Certain things first became clear to me by a mechanical 
[i.e. experimental] method, although they had to be demon- 
strated by geometry afterwards because their investigation by 
the said method did not furnish an actual demonstration. 5 

Accordingly, he weighed mechanical models of the 
parabola and ellipse, demonstrating the result by the 
geometrical method of limits, and finally generalizing 
this method to an anticipation of the integral calculus. 

5 Cited in Heidel, The Heroic Age of Science, p. 101. 



32 WHAT SCIENCE REALLY MEANS 

It is not true that Archimedes' procedure differed from 
that employed by modern science. For example, in his 
work on floating bodies, starting from the observation 
that water has the geometric property of being fluid in 
all its parts, he proceeded deductively to the conclusion 
that a solid heavier than water will lose its weight in 
water, a weight exactly equal to the weight of the water 
displaced. This he verified experimentally, and thus 
established the principle of specific gravity. Of course, 
the train of reasoning might have been different. A 
scientist of to-day might note through various experi- 
ments the weight of the displacement of a body, and leap 
to the induction that the weight of the body is equal to 
the weight of the water displaced. He might then 
formulate the principle mathematically. Both pro- 
cedures, however, are equally empirical, equally deductive 
and inductive. 

Mystic neo-Pythagoreanism continued, but scientific 
mathematics was also well under way by this time. 
The name of Euclid needs no comment; but it is not so 
well known that beside being a geometer he also worked 
on optics, discovering the propagation of light in 
straight lines, and the laws of reflection. Apollonius of 
Perga was the same type of mathematical scientist. The 
significance of his work was not so much the discovery 
of the properties of the parabola, ellipse, and hyperbola, 
but in generalizing these as sections of one cone, and thus 
in beginning projective geometry. 

The understanding of Hellenistic science as hopelessly 
theoretical is without foundation. Indeed, we have been 
attempting to show that its direction was the opposite, 



THE ORIGINS OF EMPIRICISM 33 

and that it too soon became 'practical' and positivistic. 
Philo of Byzantium, though a mathematician, is chiefly 
known as the author of an encyclopaedia of applied 
mechanics, and for his work on pneumatic machines. 
Likewise Hipparchus, though a mathematician, is mainly 
notable as an inventor of astronomical instruments, and 
for his rejection of the heliocentric system as too theo- 
retical. The same practical turn is to be seen in Hero, who 
was almost entirely concerned with the applications of 
mathematics and mechanics, and who contrived many 
machines, e.g. siphons, steam engines, and fire engines; 
Hero's Pneumatics was almost a laboratory manual. 6 

The growing interest in a positivistic point of view 
and the narrow practicality of the late Hellenistic Age are 
manifest in the next group of scientists we have to con- 
sider. Strabo, Seneca, and Pliny the Elder wrote vast 
compendia of knowledge. Vitruvius and Frontinus did, 
it is true, make contributions of a scientific nature, but 
these were chiefly practical devices which bore narrowly 
on their own work. Frontinus wrote on hydrodynamics 
in connection with the engineering of the aqueducts, 
and Vitruvius contributed as an architect to acoustics, 
and, as superintendent of military engines, to ballistics. 
Celsus and Dioscorides were both medical encyclo- 
paedists, notable recorders, but cautious theorists. 

The Alexandrian period comes to an end with two 
colossal figures, Galen and Ptolemy. With them the 
positivistic progress of Hellenistic science reached its 
culmination. Although Aretaeus, Galen's contemporary, 
was a greater physician than Galen, it was the latter 's 
6 Heidel, op. cit., p. 191. 



34 WHAT SCIENCE REALLY MEANS 

dogmatic and systematic summary which won him the 
most acclaim. 

His chief merit consists in having systematized and unified 
Greek anatomical and medical knowledge and practice. 7 

Although Galen did experimental work, e.g. on the 
sensory and motor nerves, his chief historical importance 
consists in the fact that he closed inquiry rather than 
opened it. 

Ptolemy played the same role in astronomy that 
Galen did in medicine: he systematized the science on 
positivistic lines. Note the common-sense empirical 
argument of Ptolemy against the movement of the earth: 
that if the earth were moving a bird on the wing would 
soon be left behind. Herein is indicated the abandonment 
of the attempt of Aristarchus to formulate astronomy in 
theoretical terms which go beyond the appearances of 
common sense. However, the Ptolemaic system was an 
improvement in economy over the older and more 
awkward crystalline spheres. The Ptolemaic system of 
cycles and epicycles is a summary of observations, and 
like all such summaries does not suggest any new con- 
clusions, and was "primarily a bookkeeping device." 8 
When such an ideal of science is adopted, it is the end 
and not the beginning of speculation. This alone should 
make the scientists beware of accepting the positivistic 
version of empiricism. 

The failure of late classical science to perpetuate itself 
has a simple explanation. Its separation from abstract 

7 George Sarton, Introduction to the History of Science, vol. i, p. 301 ff. 

8 Benjamin Ginzburg, The Adventure of Science, p. 68. 



THE ORIGINS OF EMPIRICISM 35 

speculation rendered it cautious and down-to-earth, to 
the extent of becoming more and more concerned with 
special practical problems and summaries of past work, 
until it died of positivism. Abstract speculation divorced 
from science fled to philosophy, there to concern itself 
altogether with ultimate problems of ontology. To 
separate science and philosophy is hurtful to both. It 
leaves philosophy without ground under its feet and 
hence in the eerie realms of mysticism; it leaves science 
flat on the ground, tied to the impotence of positivism. 
This extreme is as harmful to science as is the wild 
theorizing of a Plato, and curiously enough both result 
in pesudo-empirical sciences like alchemy and astrology. 
For, be it noted, the astrologists and the alchemists were 
of all 'scientists' the most practical in ambition and the 
most experimental in procedure however null the 
result. In this nadir of scientific research the great flower- 
ing of science was lost to the Hellenistic world to be 
resumed elsewhere. 

BYZANTINE-MOSLEM EMPIRICISM 

It is generally believed that after Hellenistic science died 
out, there was a period of perhaps four centuries when 
the whole tradition of experimental science was dead, 
and that it lay dead until Moslem culture resurrected it. 
There is no foundation for this view. The truth is that 
science shows a continuity from the ancient Greeks to 
the modern scientists; and there was never a period when 
science was abandoned altogether everywhere. After the 
decline of the Hellenistic Age, empirical science was pre- 
served in the Byzantine Empire. While it is true that 



36 WHAT SCIENCE REALLY MEANS 

there were no great Byzantine scientists, that the 
Byzantine scientists added little to the tradition, still 
they did serve the valuable function of keeping it 
alive. 

Oribasius, the last of the true Hellenistic scientists, 
flourished about A.D. 370. He wrote a medical encyclo- 
paedia in seventy books, and fought the growing super- 
stition of the age. But there is no real break between him 
and Proclus. Proclus may be termed one of the first of 
the Byzantines. He worked in astronomy, describing the 
method of measuring the apparent diameter of the sun 
by means of Hero's water-clock. In mathematics he 
worked particularly on the properties of certain higher 
curves. Martin Capella, generally known as a Christian 
theologian, set forth an explanation of the hemi- 
heliocentric system, and discussed geometry and arith- 
metic. Anthemius (fl. circa 510) was a practical mechanic 
and mathematician. He was employed in the recon- 
struction of the Cathedral of St. Sophia, but he also 
wrote theoretical treatises on the parabola, and on the 
properties of burning-glasses. His contemporary, Phili- 
ponus, was a scientist in the best sense of the word. He 
disproved Aristotle's law of falling bodies experimentally; 
denied the Aristotelian theory of the impossibility of a 
vacuum; and described astronomical instruments, especi- 
ally the astrolabe. It is not difficult to see that there is 
no qualitative difference between this kind of scientist 
and those of the late Hellenistic Age. These names must 
be considered a mere indication of the extent of experi- 
mental science. For instance, Bishop Synesius of Ptole- 
mais requested Hypatia to procure for him some 



THE ORIGINS OF EMPIRICISM 3? 

baryllium to make an hydrometer, proving that the 
instrument was well known at the time. 

Justinian, who closed the philosophical schools of 
Athens, opened one of his own devoted to the study of 
mathematics in 532. The seventh century contained 
besides physicists many medical scientists. Alexander of 
Tralles, Theophilus Protospatharius, Stephanus of Alex- 
andria, Stephanus of Athens, Aaron of Alexandria, Paul 
of Aegina, all were eminent doctors who wrote on the 
theoretical side of medicine. 

Although Byzantine science suffered a decline after the 
seventh century it never entirely disappeared, and in the 
ninth and tenth centuries underwent a renaissance. Leon 
of Thessalonica was a notable figure in this period. 
However, it was in the seventh century that Byzantine 
science reached its height and began to influence the 
countries further east, preserving the continuity between 
Byzantium and Islam. Severus of Sebokht was a 
Christian bishop who started a school of Greek learning 
in Western Syria about 650. He added to the Greek 
scientific tradition the use of Hindu numerals; without 
them the high modern development of science would 
have been impossible. 

Towards the beginning of the Byzantine period (489) 
Nestorian Christians emigrated to Edessa. They were dis- 
persed further east by religious persecution and trans- 
ferred to Ctesiphon, and in 762 they again transferred to 
Baghdad. They were the principal agents by which 
Greek science and learning were introduced to the 
Moslem world. Therefore there is no hiatus between 
Byzantine and Moslem science. It is notable that Baghdad 



38 WHAT SCIENCE REALLY MEANS 

became the great centre of Moslem culture after the 
Nestorians had settled there. 

The first Moslem scientists were mainly encyclo- 
paedists and translators. Al-Fazari, who flourished late in 
the eighth century, translated Sanscrit works and thereby 
introduced Hindu numerals to the Moslem world. This 
is the great advantage which Moslem science held over 
Byzantine. Moslem science, however, had still to free 
itself from pseudo-science, and in the works of Jabir 
we can already see signs of chemistry emerging from 
alchemy. Early in the following century Al-Quarizmi, 
syncretizing Greek and Hindu science, developed mathe- 
matics, particularly algebra, far beyond anything that 
either Greek or Hindu alone had accomplished. Al-Kindi 
and Al-Farghani made translations from the Greek, and 
the latter as an astronomer following Ptolemaic theory 
wrote on celestial motions. Ibn-Qurra illustrates again 
the great reliance on Greek sources; he translated Apol- 
lonius, Archimedes, Euclid, and Ptolemy into Arabic. 

At the beginning of the tenth century Moslem science 
had absorbed sufficient influences to become experimental 
on its own account, and its learned men attempted to 
treat of all fields of knowledge. Al-Razi was an important 
physician who combined his knowledge of chemistry 
with medical practice. He was much more than a mere 
syncretizer of Greek and Hindu medical knowledge, 
being an experimental chemist, physician, and physicist 
(hydrostatics). Al-Battani was an astronomical scientist 
who combined theory with observations; he discovered 
the motion of the solar apsides, and in his trigonometry 
employed sines instead of Greek chords. To correct the 



THE ORIGINS OF EMPIRICISM 39 

erroneous impression that Moslem science was confined 
to mathematics and the natural science, we have only 
to mention Al-Farabi, who wrote on psychology and 
social science, e.g. a work entitled The Model City, in 
which city planning is discussed. This same scientist also 
dealt with the theory of music and the theory of science 
in general. Al-Sufi was another observational astronomer, 
who made the most complete map of the fixed stars. So 
many are the Moslem scientists that the work in any one 
branch would be astonishing. In mathematics alone it is 
impossible even to give a list of all those who contributed. 

The scientist Al-Hazen made most important contri- 
butions to the study of optics, explaining atmospheric 
refraction, the apparent increase in the size of the sun 
when on the horizon (twilight phenomena), also the 
theory of lenses. He was strictly an experimental scientist 
who neither in method nor practice differs from the best 
of any period. 

Two great figures dominate the close of Arabic 
scientific genius: Avicenna and Al-Biruni. Both were 
systematizers and summarizers of all that went before. 
Though experimenters, they are chiefly remembered for 
encyclopaedias of existing knowledge, which, because of 
their completeness, unfortunately helped to sterilize 
Moslem science. Al-Biruni made geodetic measurements, 
contributed to geology, surmised the rotation of the 
earth on its axis. He was an experimental physicist, and 
pointed out that the speed of light must be immense; he 
was an observational botanist, who showed that the 
petals of flowers are never seven or nine. He fought the 
gathering forces of superstition, and objected that faith 



40 WHAT SCIENCE REALLY MEANS 

in the omniscience of Allah does not justify ignorance, 
in effect stating that reference to a final cause is for 
scientific purposes mere tautology. 

Avicenna has well been called the Aristotle of the 
Moslem world, for his systematization and encyclopaedic 
summation of all knowledge. The Canon, his famous 
medical encyclopaedia, consists of a million words, and 
was held authoritative until the middle of the seventeenth 
century. But he was a good deal more than a medical 
writer, and is known to have experimented on specific 
gravity and on the speed of light, which he declared was 
finite. Also, like Aristotle, Avicenna's attitude was 
philosophical and terminal. And by his very success he 
discouraged original scientific advance. 

After these large-scale figures there is a sharp decline in 
Moslem science, marked by a new resurgence of mys- 
ticism on the one hand and positivism on the other. 
Despite the efforts of men like Al-Zarqali and Omar 
Khayyam, science turned positivistic and toy-minded. 

Instead of being concerned with ideas, they had but a 
childish interest in automata and in mechanical toys and 
contrivances. Without further theoretical studies, their pro- 
gress in that direction was naturally very limited. 9 

Positivism again proved the death of science. After the 
twelfth century science turned toward the West. 

CHRISTIAN-MEDIAEVAL EMPIRICISM 

Although the full force of the continuous scientific tradi- 
tion was not felt in Latin Europe until the infiltration of 
9 George Sarton, Introduction to the History of Science , vol. ii, p. 22. 



THE ORIGINS OF EMPIRICISM 41 

Moslem learning, about the tenth century, there were 
already signs of a turning toward the scientific temper. 
Magic was the occasion for pre-Moslem European science, 
as witness the magic doctor, Marcellus of Bordeaux, 
who as early as 395 was already beginning to believe in 
the efficacy of experience. Magic is indeed an old thing 
in the world, having existed in the midst of the scientific 
cultures we have discussed, but it had not in these cultures 
reached the proportions which it attained in Latin 
Europe. As Lynn Thorndike says, "magicians were the 
first to 'experiment/ and . . . 'science,' originally specu- 
lative, has gradually taken over the experimental method 
from magic." 10 

The early Christians had not abandoned Greek 
science; they had been misled by such false theories as 
those of the bodily humours and the four elements. Thus 
we find at first popularized compendia of knowledge, 
such as the Herbarium attributed to Apuleius and the 
Cosmography of Aethicus. Between the years 510 and 845 
there were the Consolation of Philosophy of Boethius, 
the work of Cassiodorus, the Etymologies of Isidore of 
Seville, the work on plants, animals, and minerals of St. 
Aldhelm, the De Natura Rerum of Bede, the work of St. 
Agobard, Walafrid Strabo, Macer, and Scotus Erigena. 
In general, however, it must be admitted that this is a 
period during which empiricism was at its lowest ebb. 
Abstract thought was preoccupied with theological 
matters, and what little interest remained for science 
took at first the most pedestrian turn, as illustrated by 
the reliance on early compendia, which degenerated into 
10 A History of Magic and Experimental Science, vol. ii, p. 651 f. 



42 WHAT SCIENCE REALLY MEANS 

mere catalogues of reputed fact. Even in the study of the 
quadrivium : music, arithmetic, geometry, and astronomy, 
facts got mixed up with mystical meanings. "Music 
included a half-mystical doctrine of numbers and the 
rules of plainsong; geometry consisted of a selection of 
the propositions of Euclid without the demonstrations; 
while arithmetic and astronomy were cultivated chiefly 
because they taught the means of finding Easter." 11 

The continuous scientific tradition was brought to 
Latin Europe in the conventional manner, namely, by a 
host of translators and adapters of Arabic and Syrio- 
Hellenic science. The school of Salerno, which is known 
to have been a flourishing medical school as early as 946, 
was one of the first to receive the Arabian heritage. We 
know of at least two Salernitans, Petrocellus and Archi- 
matthaeus, but even more illustrative of the course of 
learning is Constantinus Africanus, who was born in 
Tunis and went to Baghdad to learn Moslem science. 
From Baghdad he went to Salerno, and later to the 
monastery of Monte Cassino. Also typical is the case of 
Gerbart of Aurillac, afterwards Pope, who lived in 
Christian Spain but had contact with Moslem scientists. 
He gave an account of Hindu numerals, without the 
zero, and wrote on music, geometry, and the astrolabe. 
These men were followed by a host of eleventh- and 
twelfth-century translators. Among them were Walcher 
Prior of Malvern, Plato of Tivoli, Robert of Chester, 
Hermann of Dalmatia, Hugh of Santalla, Gerard of 
Toledo, and Michael Scot. 

11 W. C. Dampier-Whetham, "Science," Encyclopaedia Britannica, 
fourteenth edition. 



THE ORIGINS OF EMPIRICISM 43 

It was in the first part of the twelfth century that 
original science began to appear. William of Conches 
confirmed the right of free speculation in natural science. 
Adelard of Bath, the most outstanding scientist of this 
period, travelled in the Moslem world and studied 
Moslem science, yet was an original scientist on his own 
account, far beyond the stage of Moslem science of the 
time. Besides introducing Hindu numerals, translating 
Al-Quarizmi's astronomical tables and Euclid's Elements, 
in his Questiones Naturales he surveys the field of natural 
science. Although many of his answers are incorrect, he 
can be called the first Christian European scientist en- 
dowed with the complete scientific mentality. He was 
impatient of dogmatism and authority and relied on 
reason backed by experimental verification. Without 
denying final cause, he stressed the necessity of efficient 
cause. Since nature "is not confused and without 
system," 12 he held that "human science should be given 
a hearing upon those points which it has covered." Reason 
without authority and with evidence was his creed; he 
was "not the sort of man that can be fed on a picture 
of a beefsteak." He anticipated the conception that 
science should be value free by saying that nothing in 
nature is impure. 

In the beginning of the thirteenth century there are 
two major figures, Grosseteste and Nemorarius, and a 
host of lesser men, e.g. Alexander Neckham, Alfred 
Sarchel, Witelo, etc. Nemorarius made original contri- 
butions to the study of mechanics, especially concerning 

12 All quotations from Adelard cited in Lynn Thorndike, op. cit., 
vol. ii, pp. 28-30 (italics ours). 



44 WHAT SCIENCE REALLY MEANS 

trajectories and, more thoroughly, statics. He applied 
the same mathematical technique to the subject as did 
later and far more famous physicists. Grosseteste also 
understood that reason and experience must co-operate 
in science. He did original work on optics and astronomy, 
saw the need of reforming the Julian calendar, and stressed 
the use of magnifying-glasses in observation. 

We have next to deal with three contemporaries of 
the middle thirteenth century: Albertus Magnus, Thomas 
Aquinas, and Roger Bacon. The first two, known better 
as theologians, experimented also. Albertus wrote on all 
subjects of natural science, and appealed to observation 
and experience, even though his contributions are after 
all meagre. Aquinas is known to have written treatises 
on irrigation and mechanical engineering. 

The third, Roger Bacon, did not, as is popularly sup- 
posed, appear in the midst of an ignorant world hostile to 
turn of mind. The prior and contemporary scientists 
which we have mentioned illustrate this point. Indeed, 
in most ways the times were propitious rather than other- 
wise. The empirical attitude manifested itself on all sides. 
Even in art, as Thorndike points out, the sculptors were 
acute observers of natural objects and indeed went 
further. They were "breeders in stone, Burbanks of the 
pencil, Darwins with the chisel." 13 Roger Bacon, then, 
was in no sense isolated. 

But he stood alone in that he emphasized the need for 

experimentation and mathematics to work together in 

science, thus pointing science towards mathematics. 

More especially, he saw the tremendous possibilities of 

13 Op. cit., vol. ii, p. 537. 



THE ORIGINS OF EMPIRICISM 45 

applied science, and constantly stressed the utility of 
scientific knowledge. He predicted the possibility of air- 
planes, steamships, automobiles, the greater practicality 
of explosives, and the Westward passage to India, which 
indirectly influenced Columbus through the Imago 
Mundi of Peter d'Ailly. His own experimental contribu- 
tions were much poorer than his vision of what science 
should be, and he was more of a herald of science than 
a scientist, as his inadequate understanding of scientific 
method proves. 

The last half of the thirteenth century showed the 
halting progress of scientific endeavour. An exception 
must be made in the case of Peter the Stranger, whose 
experimental work on magnetism and the compass 
reveals a good grasp of experimental method. Peter of 
Spain, who wrote on medicine and psychology, is chiefly 
interesting because he became Pope John XXL From the 
scientist Gerbart (Pope Sylvester II) to John XXI, to 
say nothing of innumerable monks and friars who were 
scientists, it is clearly erroneous to believe that the 
Church was hostile to science during this period. At 
the close of the century, William of St. Cloud was an 
admirable observer in the astronomical field, who made 
the first determination in Europe of the obliquity of the 
ecliptic. 

There is no doubt that there was much empirical 
science during the period we have just discussed. Experi- 
mentation is referred to again and again from the ninth 
century onward. Nevertheless, little science resulted, 
and we may well inquire why. The experimental science 
of Roger Bacon and his kind turns out to be the con- 



46 WHAT SCIENCE REALLY MEANS 

ception of science as a directly practical affair. An em- 
piricism of this sort finds it hard to distinguish between 
natural science on the one hand, and astrology, alchemy, 
and the black arts on the other. But Adelard of Bath 
sometimes in practice and Roger Bacon often in theory 
foreshadow true science, where experiment is not the 
goal of research but a part of the method. 

RENAISSANCE EMPIRICISM 

There is no break between Christian-mediaeval and 
Renaissance empiricism. However, it was in the period 
between 1300 and 1600 that science was started on its 
correct path. Unfortunately it was in this period that the 
erroneous positivistic philosophy of science also got its 
start. The revolt against authoritarian Aristotelianism 
pure deduction from principles held without the em- 
pirical sanction, the very revolt which was so fruitful 
grew until it became bitterly opposed to abstract reason. 
The rejection of one error seemed to be the signal for 
the adoption of another. The early humanists made great 
fun of the logic of Aristotle, which was afterwards 
lumped with the science of Aristotle as outmoded and 
ridiculous. 

Despite the disrupted condition of Europe in the 
century of wars and the Black Death, experimental 
science was carried on as it had been in the thirteenth 
century; with its random experimentation, uncontrolled 
theorizing, and emphasis on practicality, and yet with 
its groping toward true scientific method. There was 
more interest in magic and the black arts than ever 
before, and science reached as low a state as it had since 



THE ORIGINS OF EMPIRICISM 47 

the Greeks. Even the encyclopaedias, to which unin- 
ventive periods always resorted, were degraded affairs. 

Among such half-baked investigators of science as 
William Merle, Andalo di Negro, Profatius, Dagomari, 
Ferminius, John of Picardy, and John of Saxony, atten- 
tion was paid to arid facts still confused with astrology. 
Two men stand out from these: John de Murs and 
Richard Swineshead (called the "Calculator"), who 
flourished about 1350. The former insisted that facts 
deduced from instruments can neither be denied nor 
corrupted, and is said to have made a better astrolabe 
than the one made for Tycho Brahe. "Calculator" wrote 
a book in which there is abstract consideration of such 
physical entities as density, velocity, rarefication, etc. 
There was furthermore a tendency in the second half 
of the fourteenth century to discountenance alchemy, 
astrology, and magic in general. Petrarch, though no 
scientist, used his great influence to derogate magic. 
Nicholas Oresme devoted his life to writing books against 
it, as did his follower, Henry of Hesse. And there were 
others, such as Groot and Eymeric. 

The next seventy years apparently wrought no change 
in the development of science. Nevertheless, the ap- 
pearance of such scientists as those of the second half of 
the fifteenth century, starting with Cusa and ending with 
da Vinci, shows the widening periphery of scientific 
interests extending from flying machines to carto- 
graphy. 14 Nicholas of Cusa worked on statics, antici- 
pated Galileo by suggesting experiments to demonstrate 

14 C/. Dana B. Durand, "The Earliest Modern Maps of Germany 
and Central Europe/* in Isis, vol. xix (i933), P- 486 flf. 



48 WHAT SCIENCE REALLY MEANS 

the speed of falling bodies, and stressed the importance 
of measure in physical science. He taught that everything 
is in motion, the earth along with other planets. Regio- 
montanus had an astronomical observatory and worked 
on trigonometry; Toscanelli was an observer of cometary 
motions, as was Peurbach, who corrected the Alphonsine 
Tables. John de Fundis explained the process of erosion 
and the gradualness of geologic change. The emphasis 
on mathematics of the astronomers is notable, pointing 
to the use of mathematics in natural science. Pacioli, 
concerned with algebraic roots, worked with Leonardo 
da Vinci, who also fully understood that science must be 
expressed metrically. This he exemplified in optics, 
astronomy, hydraulics, geology, architecture. Starting 
always with an interest in particular practical problems, 
he was led to understand that only by finding the general 
principles involved could he hope to solve particular 
problems. 

The general interest of the period culminated in one of 
the greatest of all scientists. Copernicus has direct his- 
torical derivation. His teacher, Novara, of the University 
of Bologna, was thoroughly imbued with the stress laid 
upon the continuity of nature and the importance of 
mathematics as taught by the Academy of Florence. 
Also Copernicus derived encouragement for his helio- 
centric theory from the classic writers who had favour- 
ably mentioned that of Aristarchus of Samos. Nor 
would his work have been possible without the previous 
geocentric system of Ptolemy. Copernicus was mainly a 
mathematical theorist, who observed, but who did not 
really base his proofs on observation. The theory is non- 



THE ORIGINS OF EMPIRICISM 49 

empirical, in the positivistic sense of the term, since it 
did not take into account common sense or the prevailing 
data of physics. As Burtt points out, the chief merit of 
liis theory over that of Ptolemy's was one of economy, 
"saving the phenomena" by means of thirty-four epi- 
cycles instead of eighty. "Contemporary empiricists [i.e. 
positivists], had they lived in the sixteenth century, would 
have been first to scoff out of court the new philosophy 
of the universe." 15 

Copernicus was a canon and addressed De Revolutionists 
to Pope Paul III. At this time the Church's attitude 
toward science was not strictly defined. The Church 
opposed all heresy in general, in which both magic and 
science were shortly to be included without any dis- 
tinction between them. The confusion is illustrated in 
Pico dela Mirandola, who though a good Churchman 
believed in science, wrote against astrology, and yet 
endorsed the Cabala. Later the Church took a much more 
determined attitude against natural science, based on 
the seemingly anti-theological import of Copernicus's 
system. 

Meanwhile the descriptive sciences showed signs of 
development. Vesalius, in Belgium, in his De Humani 
Corporis Fabrica, corrected false anatomical descriptions 
of Galen and worked on exact anatomy. Eustachius, 
Fallopius, and Fabricius in Italy continued this work. 
Fabricius discovered the valves in the veins and was the 
teacher of Harvey. In Spain Servetus contributed much 
to anatomy. Palissy explained fossils correctly, and 

15 E. A. Burtt, The Metaphysical Foundations of Modern Physical 
Science, p. 25. 

D 



50 WHAT SCIENCE REALLY MEANS 

Agricola, in Germany, wrote on stratographic geology. 
Gesner, the Swiss, studied and classified plants and 
animals; Bauhin systematized botanical classification. 
Gilbert of England worked on static electricity and 
magnetism from a purely empirical standpoint. 

But the descriptive sciences showed no such remark- 
able development as did the physical. Observation un- 
aided is only half of science. It is true that Tycho Brahe, 
by painstaking observation at Uraniborg and later in 
Germany, where he made a giant quadrant, furnished 
the empirical data for Kepler's theoretical formulations. 
But Brahe alone would never have confirmed the 
Copernican revolution. Kepler, the mathematician, dis- 
covered the laws of planetary motion, showing that the 
planets describe ellipses about the sun in one focus, and 
that radius vectors from the sun sweep out equal areas in 
equal times. Kepler is an arch example of the complete 
scientist whose main preoccupation is with consistent 
theory but who insists that it be based on empirical 
observation. With Kepler's work, as with all great 
scientific discoveries, the field was opened rather than 
closed to new inquiry. The laws of planetary motion 
discovered by Kepler did not check with the old physical 
ideas, and so led to new physical questions and thus to 
the development of modern physics in the seventeenth 
century. All this was foreshadowed and proclaimed by 
the martyr, Bruno, who predicted such discoveries as 
the rotation of the sun, the enormous astronomical dis- 
tances, unknown planets, and the conservation of 
energy, etc. 

In looking back over these three centuries, we note 



THE ORIGINS OF EMPIRICISM 51 

two kinds of empiricism. On the one side there were 
those observers and experimenters who were seeking in 
the facts for almost anything: the positivistic-minded 
magicians, alchemists, and physicians. Almost as barren 
was the descriptive science of this period. But on the 
other side were those experimenting theorists who looked 
for principles over and beyond the mere appearances 
and who tested these against empirical fact. Alchemists 
are 'practical* men; chemists are not. The paradox is 
presented that science must abstract from practicality 
in order to arrive at principles susceptible of being 
practically applied. 

However, despite the success of such pure theorists as 
Copernicus and Kepler, the main opinion persisted even 
among scientists that science is an affair of demonstration 
only, opposed to abstract reason. The period under 
review points the direction that modern science has 
taken away from the occultists toward a further develop- 
ment of this early science. But the conviction that ex- 
perimentation is somehow opposed to abstract reason 
continued to gather momentum and remains to influence 
science to-day. 



CHAPTER III 
THE DEVELOPMENT OF EMPIRICISM 

If you want to find out anything from the theoretical 
physicists about the methods they use, I advise you 
to stick closely to one principle; don't listen to 
their words, fix your attention on their deeds. 

EINSTEIN 

SEVENTEENTH-CENTURY EMPIRICISM 

THE opposition of science to reason in the beginning of 
the seventeenth century does not at first show itself in 
the revulsion against theory but only against the current 
Aristotelianism, i.e. theory without experiment. 1 As a 
matter of fact, the scientific theories of that age would 
seem wild to a modern positivist. If Galileo and Newton 
had revolted against all theory, science would never have 
reached its great development. The chief source of the 
development of science was an acceptance of mathe- 
matical reasoning as applied to natural science. Mathe- 
matics was encouraged and developed by such men as 
Napier, the discoverer of logarithms, Descartes, the in- 
ventor of co-ordinate geometry, Cavalieri, Fermat, 
Desargues, Pascal, Wallace, etc., who covered the field 
from the theory of invisibles to probability and analytic 

1 "In the case of the vase emptied of air, Descartes asserted that 
either some other material must enter the vase or else its sides would 
fall into mutual contact; More was prepared stoutly to maintain that 
the divine extension might fill the vase and hold its sides apart" 
(Burtt, Metaphysical Foundations of Modern Physical Science, p. 138). It 
occurred to neither to appeal to experiment! 



THE DEVELOPMENT OF EMPIRICISM 53 

geometry, leading up to the work of Leibnitz and Newton 
on the calculus. But mathematics seemed to them to 
have nothing to do with logic. 

The rejection of the scholastic system alienated religion 
and the universities from the new science. The Church 
burned Bruno in 1600; shortly after this date science 
began to organize its own academies: the Accademia dei 
Lincei at Rome in 1603, followed by the Accademia del 
Cimento at Florence in 1651, the Royal Society of 
London in 1662, the Academic des Sciences at Paris in 
1666, and the Berlin Academy in 1700. Stimulated by 
the work of the academies the emphasis on observation 
led to the invention and improvement of scientific 
instruments: the thermometer, the barometer, the 
microscope, the telescope, the air pump. 

We may note two kinds of science in this century. 
The mathematico-physical sciences were highly specu- 
lative and developed rapidly. The descriptive-biological 
sciences were equally empirical but less abstractive and 
speculative, and developed very slowly. The period 
shows that empiricism is the sine qua non of science, but 
that it must not be held down to the entities of common 
observation. 

In physical science the century opens with Stevinus 
who set forth the parallelogram of forces, the principle 
of virtual displacement, and other work on statics. 
Galileo's chief originality lay in the field of dynamics, 
though, of course, he had hints from many predecessors. 

Galileo was an important experimenter. Through the 
telescope which he developed he observed sunspots, 
mountains on the moon, the satellites of Jupiter, the 



54 WHAT SCIENCE REALLY MEANS 

phases of Venus, etc. His experiments, however, were 
preceded by a study of the principles involved. 2 The 
extent to which Galileo was preoccupied with abstract 
principles and not primarily with mere exemplifications 
is shown in the manner in which he generalized from 
the inclined plane to the law of falling bodies, to inertia, 
and thus to the generalized law of motion, incidentally 
showing that his youthful discovery of the pendulum 
principle was a special case of this general law. Galileo 
understood that scientific method starts with the evidence 
of common-sense experience but comes to theories, 
experimentally verifiable, that do violence to common 
sense. 

Boyle is the first modern chemist. Basing his work on 
that of such men as van Helmont and Jean Rey, in his 
The Sceptical Chymist, 1661, chemistry is treated for the 
first time as a science, and not as an empirical art for 
working precious metals and useful medicaments. Boyle, 
in fact, did for chemistry what Galileo did for physics. 
Just as Galileo killed Aristotelian mechanics, so Boyle 
destroyed the authority of the four elements, insisting 
upon experimentation to find the true ones. Although 
himself a patient experimenter and an opponent of wild 
theories, he yet declared the principle that "experience 
is but an assistant to reason/ ' 

Two main influences led to the great synoptic genius 
of the century, Newton. First, the idea of die universe 

2 By his own account, "the report by a noble Frenchman finally 
determined me to give myself up first to inquire into the principle of 
the telescope, and then to consider the means by which I might com- 
pass the invention" (Dampier-Whetham, Cambridge Readings in the 
Literature of Science, p. 17) (italics ours). 



THE DEVELOPMENT OF EMPIRICISM 55 

as a perfect mathematical scheme, via Kepler, Galileo, 
and Barrow, his teacher. Second, the over-emphasis on 
experimentation characteristic of the whole age, led him 
to accept Galileo's atomistic mechanism with its objec- 
tive atoms and the void and its subjerive interpretations. 
It follows that these should have led to the brilliant 
scientific scheme, and to the erroneous positivistic con- 
clusions that the laws of nature are mere descriptions of 
actuality. The scientific scheme was drawn from Kepler's 
astronomy and Galileo's dynamics, generalized into the 
laws of motion and gravitation. Thus astronomy and 
physics became one science. The positivistic conclusions 
consisted of a philosophy deduced from a method. The 
method of treating phenomena in isolation had proved 
successful with Galileo, Boyle, and in his own work. He 
concluded that explanations of the whole were irrelevant, 
and declared that he did not touch hypotheses. This 
negative attitude is positivism, which derived terrific 
prestige from the fact that it was endorsed by the very 
man who gave mathematical physics its greatest impetus. 

The influence of Newton confirmed the tendency of 
the century toward a development of the mechanico- 
mathematical interpretation of the universe, and its 
investigation by experiment and mathematics. Huygens 
proceeded to develop the theory of centrifugal force, 
explaining the flattening of the earth at the poles, and 
also his wave theory of light. The development of the 
physical sciences was paralleled by an unfortunate 
acceptance of positivism. 

The biological and descriptive sciences in this century 
could not avail themselves of mathematics. In spite of 



56 WHAT SCIENCE REALLY MEANS 

such spectacular achievements as that of Harvey's dis- 
covery of the circulation of the blood, and Leeuwenhoek's 
microscopic discovery of bacteria, more than a century 
elapsed before biology reached maturity. Their work 
is almost exclusively on the level of common-sense 
observation, and mainly notable for the overthrow of 
the old Greek biological ideas. Sydcnham insisted on a 
material basis for disease, Borelli analysed the mechanics 
of muscular action, Malpighi worked on embryology 
and observed the flowing of the blood, and Hooke 
examined living tissue under the microscope. Similar 
fresh observations were made in other studies by men 
freed from old preconceptions, such as Steno, the 
Dane, who made investigations into the nature of the 
earth's crust, and Lister, who drew the first geological 
maps. This valuable spade-work must not be underrated, 
but it does not represent the same advance as that made 
by physics. The emphasis on description and classification 
bolstered the positivistic account of what science is. 

Positivism is as old as Hippocrates. 3 It has been easy 
to show how the century which saw the origins of 
modern science also saw the acceptance of the old 
positivistic misunderstanding of science. The rejection 
of final cause, together with the adoption of a mathe- 
matical universe, required a mechanistic atomism. The 
mistake arose when Galileo assumed that efficient and 
final cause are not respectively equal to the actual and 
the mathematical. This equates final cause with actuality, 
i.e. a completely determined actual world of atoms. 
Descartes exhibits this error in his 'physicalism* : all 
3 Cf. Hippocrates, De Prisca Medicina, 1-2 (I, 570 ff., L.). 



THE DEVELOPMENT OF EMPIRICISM 5? 

reality is mathematical, but all reality is also extended. 
Thus all mathematical sciences reduce to the science of 
physics. This is positivism almost in its modern dress. 

However, fortunately positivism was an induction 
from science in the seventeenth century, and science was 
not a deduction from positivism. If the latter had been 
true there would be no science. And in so far as modern 
science has taken this doctrine seriously, as in the 
descriptive branches, it has been much hindered. Fortu- 
nately and unfortunately, the early physical scientists got 
hold of a method which they employed without under- 
standing its philosophical meaning. 

EIGHTEENTH-CENTURY EMPIRICISM 

Accordingly, physical science proliferated tremendously 
in the eighteenth century. Physics and astronomy had 
already become largely systematized; in this century it 
remained for chemistry to accomplish the quantitative 
systematization. 

Astronomy, however, was not without its develop- 
ment, notably in the work of the Herschels, who dis- 
covered Uranus, and traced the motion of the solar 
system to a point in the constellation of Hercules, and 
who identified over two thousand nebulae; and in the 
work of Laplace, famous for the nebular hypothesis, and 
for celestial mechanics. Other branches of physical 
science which were developed included acoustics and the 
theory of heat. One of the most prolific developments of 
physical science in this century was the discovery of the 
rudiments of electromagnetism. Grey and Wheeler at 
the beginning of the century found that electricity could 



58 WHAT SCIENCE REALLY MEANS 

be transmitted through certain substances. Dufay dis- 
covered that electrical charges were of two kinds, positive 
and negative. Von Kleist, Musschenbrock, and William 
Watson were responsible for the understanding of 
electrical induction. Franklin showed that lightning was 
an electrical manifestation. Coulomb demonstrated that 
an electric charge has magnetic properties. But perhaps 
the greatest impetus was given to the study by the dis- 
coveries of Galvani and Volta at the end of the century, 
that electricity is generated by chemicals as well as by 
friction. 

Meanwhile mathematics pure and applied continued 
the splendid development of the previous century, in the 
work of Maclaurin, who systematized the calculus; 
Euler, who established analysis as a study independent of 
geometry. Bernoulli, D'Alembert, and La Grange further 
applied mathematics to mechanics and dynamics. 

By far the most important scientific advance was that 
made by chemistry. Moreover, it best illustrates the 
manner in which a science should proceed. The interest 
in chemistry was given a new impetus when the theory 
of phlogiston was challenged by the experiment of Dr. 
Joseph Black in 1756. By heating quicklime he showed 
that there is a loss of weight exactly equal to the amount 
of "fixed air" given off, and thus that fixed air (CO 2 ) 
is a constituent of the atmosphere. Bergmann soon 
found that "fixed air" is not air, but the compound, 
carbon dioxide. Cavendish in 1766 isolated "inflammable 
air," which on burning condensed into water. The 
significance of the combination of inflammable air 
(hydrogen) with the oxygen of the atmosphere to form 



THE DEVELOPMENT OF EMPIRICISM 59 

water was not understood until Watt and Lavoisier re- 
peated the experiment. Rutherford in 1772 discovered 
that "inert air" was nitrogen. 

Independently Scheele and Priestley discovered oxygen, 
which the latter termed "dephlogisticated air/' He 
found that it would support combustion and respiration 
better than ordinary air. It should be noted here that 
although superficially this chemical experimentation 
appears as a trial-and-error random affair, it yet was 
directed by certain pro tern, accepted hypotheses, with- 
out which there could have been no revelatory experi- 
mentation. 

How the progress of science works is best shown by 
the chemical labours of Lavoisier, who put together 
Boyle's ideas of the elements with the discoveries of the 
preceding eighteenth-century chemists, to form a quan- 
titative system which gave a terrific spurt to further 
quantitative research, leading to Dalton's atomic theory 
and thus to the whole of modern chemistry. Convinced 
that no ponderable matter disappears in chemical changes, 
Lavoisier carefully interpreted quantitative results, and 
in this way arrived at the conclusion that the different 
"airs" of his predecessors were chemical elements. 

Robert Boyle had "pleaded for a closer relation 
between experimental facts and theoretical speculation." 4 
But the unity of experiment and speculation need not be 
simultaneous in time or contained in the same person. 
Thus a hundred years elapsed between Boyle's definition 
of chemical elements and Lavoisier's organization of the 
table of chemical elements, in which the latter drew on 
4 Douglas McKie, Antoine Lavoisier, p. 59. 



60 WHAT SCIENCE REALLY MEANS 

the interim experimental work. Thus without the defini- 
tion, there would have been no experiments capable of 
determining specific elements; but without the experi- 
ments the definition might have remained an arid hypo- 
thesis. With the two, though separated by a century, 
there resulted a valid and progressive science of chemistry. 
Had Lavoisier not systematized chemistry, he would 
have accomplished little more than Priestley, Black, and 
Scheele, and chemistry would still be an affair of piece- 
meal and unrelated experimentation. 

During the eighteenth century there was much work 
done in the descriptive and biological sciences. It did not, 
however, prove to be of the sort which leads to a valid 
and fruitful system. There was some development in 
physiology, comparative anatomy, embryology, and 
'natural history.' Natural history included botany, 
zoology, and geology. Physiology was connected with 
medicine, but was not understood to be significantly 
related to zoology. Buffon, in his Natural History, 
described all known species of animals. Linnaeus classified 
all known plants. Both were painstaking and accurate, 
and the latter's classifications were worked out in great 
detail. Nevertheless, description and classification do not 
constitute the abstract systematization which is the aim 
of science. They do not, because they remain on the 
qualitative level, allowing of no mathematical applica- 
tion. But as we have seen, science progresses in direct 
ratio to its employment of the mathematical method. 
Any elaborate qualitative system, such as Buffon and 
Linnaeus set up, hinders rather than accelerates scientific 
progress. 



THE DEVELOPMENT OF EMPIRICISM 61 

What eighteenth-century science demonstrates is that 
there are different levels of empiricism. Certainly descrip- 
tion and classification are as empirical as the experi- 
mentation of Laplace and Lavoisier; but in the former, 
observation remains at the common-sense level, or at 
best systematization is accomplished by qualitative 
categories. These two men worked with quantitative 
relations, arcana to ordinary observation. For positivism, 
if logically carried through, description would be the 
most valid, classification next, and quantitative synthesis 
last. But progress in scientific research has illustrated that 
increasing validity lies in the other direction. 

NINETEENTH-CENTURY EMPIRICISM 

It was in the direction of increasing systematization that 
the development of the nineteenth century lay, at least 
in the physical sciences. But it took on a special phase. 
Many new branches of the physical sciences were ex- 
plored, and the systematization showed unification by 
means of interconnection between these new branches. 
In biological sciences there were brilliant discoveries, far 
more brilliant than those of previous centuries, but little 
unification was accomplished. 

The increasing specialization and unification are shown 
in many fields. The relation between chemistry and 
physics proceeded from Dalton's atomic theory to the 
periodic law of the table of elements of Mendeleef. The 
relation between electricity and other forms of energy 
was first shown by Ampere and Ohm; the relation 
between electricity and magnetism by Faraday and Max- 
well. And all these were embraced by Hertz's discovery 



62 WHAT SCIENCE REALLY MEANS 

of the electromagnetic nature of radiant energy. In other 
ways electricity, chemistry, and radiant energy were 
shown to be interrelated, as with the discovery of 
electrolysis by Arrhenius, the polarization of light by 
Fresnel and Young, the X-ray by Roentgen, radio- 
activity by Becquerel, and the properties of radium by 
the Curies. 

Even more generally, the interconnectivity between 
forms of energy was exhibited by Avogadro, Sadi 
Carnot, and Fourrier in their work on thermodynamics, 
followed by that of Helmholtz, Joule, and Kelvin, 
Clausius and Boltzmann on the conservation and degra- 
dation of energy. To give but one example of the high 
specialization which took place, we have but to mention 
so elementary a science as geology, which was divided 
into the sciences of stratigraphy, mineralogy, petro- 
graphy, petrology, and palaeontology. On the other 
hand, many more interconnections between sciences 
were shown than those we have mentioned, such as 
physiological chemistry, biochemistry, chemical biology, 
etc. There were the sciences of spectroscopy, which 
showed among other things the relation between radia- 
tion and chemistry, and crystallography, which showed 
the relation of geometry to chemistry. In chemistry, 
geometric properties as well as arithmetic ratios were 
demonstrated. 

Mathematics in the nineteenth century went further 
than it had in all its previous history. Not only was it 
developed along with its application to physical sciences, 
but also, as pure, it forged so far ahead of application 
that even its adherents could conceive of no possible 



THE DEVELOPMENT OF EMPIRICISM 63 

field of application for the new systems. Legendre, 
Jacobi, Cauchy, and Abel developed the theory of 
elliptical functions, Cayley is responsible for the theory 
of matrices, and, with Gauss and Sylvester, for the theory 
of invariance. Gauss, one of the three masters of modern 
analysis, also set forth the properties of imaginary 
numbers, while Lobatchewsky and Riemann worked out 
independent systems of non-euclidean geometry. Weier- 
strass, Klein, and Poincare improved the theory of 
functions. Sir William Hamilton developed quarter- 
nions, and Cantor the theory of irrationals and of trans- 
finite numbers. 

During the nineteenth century 'natural history' was 
divided into geology, botany, zoology, and physiology, 
and these in turn were further subdivided. Two types of 
investigation in the whole biological field predominated; 
these we may call the microscopic and the macroscopic. 
In the microscopic field von Baer in 1828 founded the 
science of embryology, discovered the human ovum. 
Ten years later Schleiden and Schwann developed the 
cellular theory, which Claude Bernard organized into 
the science of cytology. Virchow, following up this work, 
recognized the part played by the leucocytes in pathology. 
Pasteur made his famous discoveries of the functions of 
micro-organisms in chemistry and the etiology of disease, 
thus paving the way for a new type of surgical asepsis 
and medical practice. Following the work of Pasteur, 
rapid progress was made in segregating the micro- 
organisms of typhoid, tuberculosis, diphtheria, bubonic 
plague, etc. And the science of immunology made rapid 
strides. 



64 WHAT SCIENCE REALLY MEANS 

The work on evolution accomplished in the nine- 
teenth century started with the speculations of Lamarck, 
on the origins and development of living organisms. The 
Origin of Species, published in 1859, released a storm of 
controversy. To be sure, in spite of the enthusiastic claims 
of Darwin's followers, investigation at this level can 
hardly be called exact science, though it pointed the way 
toward scientific research into the laws of heredity, 
which were worked out statistically by Mendel, and 
studied at the empirical level by de Vries and Bateson. 
These latter men created the science of genetics which 
attempts to discover the mechanism of heredity and 
variation in biologic elements. 

In this century the social sciences may be said to have 
first been studied with abstraction. They are mentioned here 
for their ambition rather than for their accomplishment, 
because it can hardly be said that any social science, with 
the possible exception of economics, has begun to reach 
the level of abstraction at which a study becomes a 
science. Psychology in this period was first officially 
introduced to the laboratory and began to assume the 
status of an experimental science. 

The nineteenth century also witnessed the culmination 
of the materialistic conception of the universe, and the 
triumph of the mechanical model, in keeping with the 
Newtonian understanding. Accordingly, all actuality 
was thought to be a strictly deterministic affair, and 
thus cause-and-effect an historical chain which goes back 
to the infinite past. In this scheme it was hard to place 
the mental realm, since it appeared to be an intruder 
into this tidy universe, and thus insusceptible to the 



THE DEVELOPMENT OF EMPIRICISM 65 

mathematical laws which otherwise rule. This inability 
to place mentality was one of the causes of the confusion 
regarding psychology and the social sciences. But the 
greatest confusion obtained in regard to the meaning of 
mathematics: since mathematics had been demonstrated 
to be the best tool for the discovery of the laws of 
nature, it must somehow be connected with the material 
world. On the other hand, since it is a manifestation of 
the human intellect, it is unmistakably mental. Pro- 
vided mind and matter are categorically distinct, how 
can mathematics as imbedded in the nature of things be 
mental; or how, if it be mental, can it accord with the 
nature of things ? This positivistic dilemma was largely 
responsible for the misunderstanding as to what science 
really means. Such was the status of scientific theory at 
the opening of the twentieth century. 

TWENTIETH-CENTURY EMPIRICISM 

In this section we must abbreviate, for although the 
period under consideration is only thirty-six years, so 
great an acceleration in scientific activity of all kinds has 
taken place that it would be quite impossible to give 
more than a cursory account. The exposition must be 
confined to the most significant developments rather 
than to the many subsidiary contributions. 

The branches of biology which have been developed 
in the twentieth century are startlingly numerous. There 
have been marked advances in old biological sciences, 
and new sciences added to the list. For instance, the 
science of genetics has gone forward under the leader- 
ship of T. H. Morgan, through the discovery of muta- 



66 WHAT SCIENCE REALLY MEANS 

tions and genes. Bayliss and Starling since 1902 have 
introduced the science of endocrinology, or the study of 
hormones, which has had so many repercussions in the 
practice of medicine. Hopkins, starting in 1912, dis- 
covered the vitamins, which have been gradually sub- 
divided into various types. Allergy and immunology 
have been made into fruitful fields of inquiry. 

Two difficulties present themselves to the science of 
biology conceived as a general science. The first is the 
random and seemingly unrelated nature of biological 
investigation, and of discoveries so greatly multiplied 
that the task of synthesis appears almost insuperable. 
The second is that in too many fields investigation is still 
held down by the nineteenth-century conceptions of 
Darwin and Pasteur. Thus the favourite explanation for 
the etiology of all disease is still the micro-organic one, 
and the favourite explanation of all organic modification 
is still the developmental one of mechanical evolutionism. 
It is easy to say that the much needed synthesis of biology 
will come in due time; but time alone is not enough, 
for the right scientist is required, one who will take a 
synoptic view which present biology is hardly calculated 
to encourage. 

The case of physical science in the twentieth century 
has been far otherwise. Indeed, it accomplished the 
greatest unification of its entire history. Curiously, this 
unification was first suggested through difficulties en- 
countered with the mechanical model of the universe. 

The hypothetical ether was called on to carry different 
kinds of waves, and thus a substance with properties 
which could neither be discovered nor imagined. Ex- 



THE DEVELOPMENT OF EMPIRICISM 67 

periments on the ether led to the famous attempt of 
Michelson and Morley to determine the ether drift. The 
null result of this experiment, which was performed in 
1887, called for a new explanation, which was first 
attempted in terms of the old physics. Fitzgerald, Lorenz, 
and others at the beginning of the century worked out 
transformation equations which saved the appearances 
but which called for a systematic deception on the part 
of nature, incredible to the scientific world. The problem 
was resolved by the subordination of the Newtonian 
formulation of space and time. Einstein in 1905 an- 
nounced his special theory of relativity, whereby space 
and time are relative to a given frame, the speed of light 
remaining the only constant. Minkowski, in 1908, em- 
ploying non-euclidean geometry, showed that what the 
special theory involved was a four-dimensional con- 
tinuum. Einstein in 1916 with his general theory of 
relativity worked out the mathematical formulation in 
terms of the tensor calculus of Levi-Civita, a postula- 
tional system giving the formulations for any frame. It 
has no picturability. 

Sub-atomic physics underwent a similar revolution, 
starting from the discovery by Becquerel in 1896 of 
radio-activity, whereby the atom was shown to be a 
complex of still more fundamental particles. Five years 
later Max Planck discovered that the interchange of 
energy proceeds not gradually, as had been supposed, 
but rather discontinuously, in atomic lumps of action 
called quanta. Meanwhile attempts at a mechanical model 
were made successively by Thomson, Rutherford, and 
Bohr, comparing sub-atomic mechanics with celestial 



68 WHAT SCIENCE REALLY MEANS 

mechanics. It was discovered, however, that the inter- 
change of energy within the atom in no way responded 
to mechanical treatment, but that Planck's principle of 
the quantum was involved. With Heisenberg, Dirac, and 
Schrodinger employing the theory of matrices, non- 
commutative algebra, and Hamiltonian functions, in the 
period 1925-26, a new sub-atomic theory, sometimes 
called the quantum theory, was devised entirely in non- 
picturable terms one which contradicts practically every 
tenet of classical mechanical physics. 

Thus in both departments of physics, the mechanical 
model definitely broke down and was supplanted by the 
mathematical model. "Material points consist of, or are 
nothing but, wave systems." 5 The change from the 
mechanical model to the mathematical model involves 
the change from categories of sense experience to cate- 
gories of objective instruments. As Planck himself has 
said, "It is much easier to establish exact physical laws 
if the senses are ignored and attention is concentrated on 
the events outside the senses. . . . The eye gave way to 
the photographic film, the ear to the vibrating mem- 
brane, and die skin to the thermometer." 6 Physics has 
left the description of actuality for the systematic ex- 
ploration of relations which are its invariables. 

The most striking thing about abstract science is its 
use of mathematics, and particularly significant is the 
relatively high applicability of scientific principles which 
were formerly considered pure, as in the use of matrices, 

6 Schrodinger, cited in Dampier, A History of Science, p. 412. 
6 Planck, The Philosophy of Physics t pp. 16-17 (George Allen & 
Unwin Ltd.). 



THE DEVELOPMENT OF EMPIRICISM 69 

the tensor calculus, etc. The development implies a higher 
and higher level of abstraction, which, as it rises in 
abstractiveness, accelerates in its advance. 

But in the abandonment of the conception of science 
as a description of actuality, certain difficulties ensued. 
Causality no longer appeared valid, and indeterminacy in 
actual sub-atomic events refuted the locked temporal 
chain of cause and effect. The implied moral, that science 
deals with a mathematical realm, of which actuality is 
only a probabilistic approximation, has been erroneously 
read as though causality were ruled out of the physical 
world, and as though all that could be known were laws 
of probability. The disappearance of the mechanical 
model and of the old interpretation of causality has been 
responsible for two kinds of interpretation of what 
science really means. On the one hand, there is the school 
of objective mentalism of Eddington and Jeans. On the 
other hand, there is an attempt by the conservatives to 
save what can be saved of the old picturable model, 7 
at the expense of the reality of natural law. This has taken 
the form of the revival and emendation of positivism. 

EMPIRICISM MISUNDERSTOOD 

This rapid survey of the history of science has brought 
out the fact that empirical science of a sort has had a 
continuous history from early Greece to modern times. 
The halting progress of science prior to the middle of 
the sixteenth century apparently cannot be blamed on a 

7 Cf. Bridgtnan's attempt to find the residue of the "physical models 
of classical theory" in the text accompanying the equations of 
mathematical models, in The Nature of Physical Theory. 



70 WHAT SCIENCE REALLY MEANS 

lack of experimentation but rather on the use to which 
experiment was put and to the narrow practicality of 
scientific ideals. Experimental science had to rise out of 
magic and into the use of mathematics; whereas theo- 
retical considerations had to come down out of 
theology and submit themselves to empirical checking. 
The meeting of both movements resulted in modern 
science. 

Experimentation seems to have gone hand in hand 
with unsuccessful as well as with successful scientific 
endeavour. Certainly there has been no valid science 
without it, as is exemplified by Archimedes and the 
Alexandrians as well as by Galileo and Faraday. But just 
as certainly there has been much invalid science with it, 
as is exemplified by the alchemists and astrologers of the 
fourteenth century. We may conclude that experi- 
mentation does not make the difference between science 
and pseudo-science, although it is one of the necessary 
elements of true science. What then is the difference 
between the kind of experimentation which produces 
science and the kind which fails ? A consideration of the 
history of science should suggest an answer. Where 
empiricism is understood as held down strictly to 
common sensory observations, science can get no 
further than description and classification, or so-called 
empirical laws, i.e. inductions drawn at the qualitative 
level of common sense. When, however, empiricism is 
understood as the discovery of relations which sensory 
observation leads to but which are not themselves 
sensory, there emerge the beginnings of a quantitative 
science with its abstract causal laws. 



THE DEVELOPMENT OF EMPIRICISM 71 

Had Galileo drawn only the induction that all falling 
bodies drop at the same rate irrespective of weight, this 
would have been a positivistic summary, a 'statistical 
law,' which incidentally would only have been true 
more or less, since it would not have taken into con- 
sideration countervailing forces present in uncontrolled 
conditions. So framed, it would certainly never have 
suggested the law of inertia. It is because such scientists 
as Galileo and Newton recognized the empirical nature 
of entities like 'force,' 'space,' and 'mass,' which are not 
completely equatable with anything actual, that they 
were able to formulate laws of a generality great enough 
to be applicable to varying conditions of actuality, and 
thus practical in the largest sense of the word. The 
reason the positivistic Greek physiologists did not dis- 
cover the circulation of the blood, may be laid to their 
prohibition against looking for anything which was not 
immediately perceptible, the circulation of the blood being 
not in itself a sensory fact but observable only in its 
function. No such non-sensory empirical fact can be 
arrived at without sought-for relations. This involves 
theory as well as fact. 

The guiding ideas and the procedure of the great 
scientists illustrate that they have always been pre- 
occupied with the discovery of relations and with the 
necessity of weaving these into an abstract system. 
They went to the sensory phenomena of nature only 
for suggestion, allowance, or confirmation of theories of 
underlying relations which could be formulated as ab- 
stract causal laws. Convinced of the continuity of nature, 
they have always been concerned to show the interrela- 



72 WHAT SCIENCE REALLY MEANS 

tions of these causal laws, thereby endeavouring to reveal 
nature's system. This they have sought to accomplish in 
two ways. First, they have aspired to consistency, order, 
and unity within their sciences, by finding laws of a 
generality which would show all laws of a lesser generality 
as special cases. Secondly, they have worked toward 
more specific relations. This direction of endeavour has 
been misunderstood to mean the direction toward actual 
sensory fact, but it is nothing of the sort. 'Tuberculosis' 
is a more specific function than 'respiratory disease' or 
'disease,' but none of them refers necessarily to actual 
facts. 

This attempt to find the abstract regularity in pheno- 
mena cannot, however, be arrived at by pure speculation, 
as Plato supposed. But neither can it be found by dumb 
observation, as Francis Bacon supposed. It can be found 
only through the judicious use of speculation carefully 
held down by, and corrected according to, the observa- 
tion of phenomena. Once tested, principles become in 
turn empirical facts, and are employable as data for 
further speculation and empirical demonstration. 

Philosophical empiricism is therefore clearly not the 
implicit philosophy of science, since it holds that the 
only valid appeal to truth is limited to sense experience, 
and that by consequence abstract reasoning is suspect. 
This was the view of the British school of Locke and 
Hume. Supposing that science was talking about pheno- 
mena and not about abstract functions, Hume showed 
that sensation presents no linkage of cause-and-effect 
relation, but only the temporal succession of one event 
after another. It would follow from this that causality 



THE DEVELOPMENT OF EMPIRICISM 73 

is a mental grouping of sense experiences, and thus 
insusceptible of objective proof. This contention was 
based on an entire misunderstanding of what science 
really says. Science does not say with Hume that the 
cause of the melting of wax is the heat which precedes 
the melting. Rather it states the general principle that 
heat accelerates the molecular velocity, and that at a 
certain velocity the mass reaches the liquid state. It is 
not the temporal succession of the demonstration which 
is interesting to science, but the conditions necessary for 
this transformation at any time or place. This function 
is the linkage of cause and effect, which Hume stated to 
be non-empirical. Such a function is not at the level of 
common-sense experience, but it is empirical none the 
less. 

Although the empirical philosophy did not stop 
scientific progress, the effect of it was toward rein- 
forcing scientists in their erroneous belief that experiment 
is the whole of method and that principles are sum- 
maries of actual experiments. Plainly, this does not agree 
with the procedure of science. With the employment of 
abstract reason and the use of general principles, not to 
mention mathematical analysis, scientific empiricism 
will be recognized as essentially a rational and logical 
procedure. Thus the distrust of abstract reason by the 
scientists is misplaced; it should be directed against un- 
bridled rationalism. Yet it is because of this anti-rational 
orientation that modern science has come to look 
askance at philosophy, and has preferred to take refuge 
in the irrational doctrines of positivism. What science 
objects to is bad philosophy; but it does not avoid bad 



74 WHAT SCIENCE REALLY MEANS 

philosophy by running from one bad philosophy to 
another equally bad. The time has come when science 
faces the necessity of discovering its true philosophy. 
This can be accomplished only by a thorough-going 
analysis of empiricism. 



CHAPTER IV 
MODERN MISCONCEPTIONS OF EMPIRICISM 

Both romantic idealists and positivists banish 
rigorous reason as a true integral part of the 
natural world. 

M. R. COHEN 
FROM HUME TO COMTE 

WE have shown that the philosophical understanding 
of empiricism does not accord with the procedure of 
science. Although such radical empiricism as Hume and 
his followers set forth did not affect this procedure, it 
did reinforce the scientists, already biased in its favour, 
in their view that science is primarily empirical and that 
empiricism is basically irrational. Philosophical thought 
from Hume onward did not change this tendency but 
rather emphasized it. In spite of the many reactions 
against radical empiricism (positivism) in philosophical 
circles, reactions which were regarded by the scientists 
as flights of unscientific fancy and moony-eyed idealism, 
the positivistic view became more and more widespread. 
The eighteenth-century Enlightenment took for granted 
the world-view of mechanistic materialism as a locked 
system, but dwelt on the freedom of the human mind 
to manufacture whatever conceptions it required and 
thus to make over social life. Here was an absolute 
hiatus between the brute facts of experience and the 
reasoning powers of man. Diderot, Condillac, Condor cet, 
and other 'rationalists' interpreted this dichotomy as 



76 WHAT SCIENCE REALLY MEANS 

favourable to the intellect; thus the title of the 'Age of 
Reason' has been given to this period. 

But to Rousseau and the romantic school, another 
interpretation appeared just as satisfactory, namely, that 
reason is a spurious and unreliable guide, and that man 
should rely altogether on feeling and 'natural fact/ 
Disregarding the point that Rousseau was hardly a 
thinker at all, and that Hume was a very exact thinker, 
we may note that both arrived at the same conclusions 
due to the premises they implicitly accepted: that sense 
experience and not abstract reason gives the most indu- 
bitable evidence on which to build permanent and 
positive knowledge. 

Without considering the tremendous import of Kant's 
attempted resolution of the dilemma between reason and 
phenomena, it may be said that in its effect the philosophy 
of Kant was more influential on the side of radical 
empiricism than on that of rationalism. Kant maintained 
that we cannot have knowledge of the supersensory, 
and that metaphysics which attempts it is pseudo-science. 
Kant himself modified his position on the impossibility 
of metaphysics, yet the notion that metaphysics is 
'mind-spinning' prevailed in scientific-philosophical 
circles. Thus, more and more, scientists and the edu- 
cated public in general were led to the belief that science 
is altogether concerned with the sensible world of 
phenomena, and that philosophy is engaged in talking 
about mere concepts of the mind. That such a belief 
should assume the proportions of an explicit system was 
to be expected. This was accomplished by the posi- 
tivistic school of Saint-Simon, Comte, Littre, in France, 



MODERN MISCONCEPTIONS OF EMPIRICISM 77 

and the utilitarian school of Bentham and the Mills in 
England. 

EARLY FORMULATIONS OF POSITIVISM 

The primary purpose of Comte's positivism was the 
rational reform of society by scientific method, thus 
instituting the idea of sociology, or the science of society. 
In so doing, of course, he had first to define science and 
scientific method. Science according to Comte is that 
stage of positive knowledge which is reached after 
traversing the theological and metaphysical stages. The 
third stage, the positive or scientific, abandons the 
attempt to find absolute causes and contents itself with 
invariant relations between facts established by the 
method of observation. This knowledge is sufficient for 
practical purposes, and the attempt to reduce everything 
to unity is a mere subjective tendency of the mind. 
Experience proves it impossible. Comte was not a 
scientist and had no knowledge of scientific experi- 
mentation. So he concluded that invariant relations could 
be found by the mere observation of phenomena at the 
ordinary level of sense experience. If he had known 
more about science he might have realized that the 
objects of observation of experimental science do not 
stop with empirical entities overt to untutored eyes. 
But through lack of this understanding, he was led to 
the false assumption that the laws of science are mere 
summaries of past observation. 

John Stuart Mill arrived independently at a position 
very close to that of Comte; but, as he himself asserted, 
he was for a time a disciple of Comte, though he de- 



78 WHAT SCIENCE REALLY MEANS 

veloped another side of positivism. He went much 
further than Comte into the methodology of science, 
particularly into the inductive method. It was the 
emphasis on the inductive side of scientific reasoning 
which led Mill to undcr-emphasize the part of deduction 
and to see induction too narrowly as derived from sense 
experience. Thus an induction was for him a generaliza- 
tion of uniformities in phenomena, and this uniformity 
among phenomena he called the laws of nature. A law 
to Mill was a name for observable uniformities and not 
in itself a part of nature. Looked at in the historical 
order, cause and effect became the inevitable temporal 
relation of antecedent to consequent. Thus he did not 
understand causality non-temporally, as it is presented in 
such a science as chemistry, i.e. as the involvement of 
one function with another, capable of being presented 
as the succession of actual experiments which exemplify 
it. Mill's failure to isolate causality from the temporal 
order was occasioned by his acceptance of the associa- 
tionist psychology of Hartley which defines ideas as the 
mere succession of images in the mind. Thus scientific 
functions were not disconnected from the perception of 
them, and logical factors were confused with their con- 
ception by the mind, i.e. logic was made a branch of 
psychology. 

The net effect of Mill on those scientists who read him 
at all was toward increasing their conviction that the 
whole of science is the observation of phenomena, and 
that the concepts of science are mere mental summaries 
of experience. So-called latter-day English empiricism 
turns out to be positivism. From it flow modern posi- 



MODERN MISCONCEPTIONS OF EMPIRICISM 79 

tivism on the one hand and mentalism on the other. 
Neither Comte nor Mill understood the whole of 
scientific procedure. Many of the principles of science 
derive their authority from the manner in which they 
embrace and generalize other principles already found, 
and often it is not until later that they are experimentally 
'proved/ Comte and Mill fell back into almost com- 
plete subjectivism in the very act of seeking a firm 
empirical objective basis for science. Psychological 
certitude has nothing to do with objective truth (as far 
as science is concerned). 

The certainty which science aims to bring about is not a 
psychologic feeling about a given proposition but a logical 
ground on which its claim to be truth can be founded. 1 

The unfortunate introduction of the observing subject 
into the observed field has led the understanding of 
empiricism astray. 

MACH, POINCARE, PEARSON 

The positivistic bent of scientific theory was carried 
forward into the later nineteenth century principally by 
three men: Mach, Poincare, and Karl Pearson. It is 
interesting to note that these three men were scientists, 
and that their work had a wide currency among other 
scientists, thus showing the greater and greater acceptance 
of positivism by scientists themselves. 

Ernst Mach, a physicist, attempted to interpret physics 
entirely in terms of psychology. That is to say, he held 
that science ought to be "confined to the compendious 
1 Cohen, Reason and Nature, p. 84. 



80 WHAT SCIENCE REALLY MEANS 

representation of the actual/' 2 Mach meant that sensa- 
tions make up the stuff of reality, whether experienced or 
not, but ideas which connect them are mental fictions. 
Two things are evident in this scheme: first, that science 
is pure description of sensations, and secondly, that no 
natural laws exist, laws being but summatory fictions. 
On this view, scientific entities, such as atoms, are 
fictions, but sensations (which never appear atomisti- 
cally!) are real atoms. In this extreme attempt to hold 
science down to the vividity of actuality and disallow 
real mathematical relations, we get no picture of any- 
thing which resembles the world of science, for science 
is concerned not with sensuous imagery but with abstract 
relations. Mach escaped complete subjectivism only by 
using the term 'sensation' as though it were non- 
psychological. We can already see how close to posi- 
tivism is subjectivism, though the ambition of the former 
is to escape 'mind-spinning' and to concentrate on the 
objective and undeniable. 

In the case of Poincare the same tendency is evident. 
Poincare was a positivist, yet scattered throughout his 
writings there was the attempt to get outside of the 
charmed subjective circle. Instead of trying to make 
psychological sensations the stuff of the world, as did 
Mach, he took the social mind, particularly as it under- 
stands mathematical relations, and made it the objective 
world. 

Does the harmony the human intelligence thinks it dis- 
covers in nature exist outside this intelligence? No, beyond 

2 Mach, The Analysis of Sensations, preface to the fourth edition 
(Eng. trans. Chicago, 1914, Open Court), p. xii. 



MODERN MISCONCEPTIONS OF EMPIRICISM 81 

doubt a reality completely independent of the mind which 
conceives it, sees it or feels it, is an impossibility. A world 
as exterior as that, even if it existed, would for us be forever 
inaccessible. But what we call objective reality is, in the last 
analysis, what is common to many thinking beings, and 
could be common to all; this common part, we shall see, 
can only be the harmony expressed by mathematical laws. 3 

But despite this effort to set up a quasi-objective realm 
of pure mathematics for science, Poincare is thrown back 
upon subjective feeling in defining objective fact. 

When it is said that we 'localize' such and such an object 
at such and such a point of space, what does it mean ? 

It simply means that we represent to ourselves the movements 
it would be necessary to make to reach that object. 4 ' 

Of course this is nothing more than pure operationalism 
of the later Bridgman variety. And that it reduces to 
subjectivism of the Machian brand Poincare himself 
could not avoid. 

None of our sensations, isolated, could have conducted us to the 
idea of space; we are led to it only by studying the laws, according 
to which these sensations succeed each other? 

What Poincare is constantly confusing is the way in 
which ideas are conveyed to the mind and the meaning 
of those ideas. In discussing mathematics this leads him 
to confuse mathematical relations with the symbols used 
to express them. Certainly it may be admitted that 
mathematical symbols are a convention, without thereby 

3 Poincar, The Foundations of Science, p. 209. 

4 Ibid., p. 70. 5 Ibid., p. 71. 

F 



82 WHAT SCIENCE REALLY MEANS 

admitting that the relations they express are also con- 
ventional, arbitrary, or mental. 

Karl Pearson agrees with Mach and Poincare in seeing 
scientific laws mainly as summaries of experience, 
psychological or historical. Scientific laws 

simply describe, they never explain the routine of our per- 
ceptions. The sense impressions we project into an 'outside' 
world. 6 It [scientific law] is a brief description in mental 
shorthand of as wide a range as possible of the sequences of 
our sense-impressions. 7 

This is the familiar error of assuming that because all 
which the eye sees is seen by the eye, all must be of 
the nature of eye. Thus Pearson too confuses scientific 
laws with the sense-impressions whereby scientists have 
been able to discover them. The confusion is between 
the psychological fact of knowing and the logical con- 
ditions of knowledge. Quite naturally Pearson as a 
positivist denies any connection between sequences of 
events other than the mental "routine of perceptions," 
and thus with Hume makes causality a non-empirical 
fact. 

We are neither able to explain why sense-impressions have 
a definite sequence, nor to assert that there is really an element 
of necessity in the phenomenon. 8 

All positivists make the mistake of confusing causality 
with the temporal sequence of experience, the latter being 
only a special and therefore often misleading exemplifica- 
tion of the former. 

6 Karl Pearson, The Grammar of Science (London, 1892, Scott), p. 99. 

7 Ibid., p. 135. 8 Ibid., p. 140. 



MODERN MISCONCEPTIONS OF EMPIRICISM 83 

"The compendious representation of the actual" of 
Mach, the "sensations [which] succeed each other" 
of Poincar, and the "routine of our perceptions" of 
Pearson, are all the same. A like confusion prevails in 
all three: that of identifying the succession of experience 
with that which is experienced, the first being a psycho- 
logical, the second a logical, fact. If with these men 
we wish to confine science to descriptions of actual 
happenings, we get away from the succession of 
psychological experiences only to fall into the temporal 
succession of history. There is an objectivity to the latter 
which has recommended it to scientists. 

THE MENTALIST VIEW 

The "compendious representation of the actual" might 
have passed muster as a description of science in Mach's 
day, when the mechanical model of the universe domi- 
nated physical science. But with the introduction of 
relativity and quantum physics, the mechanical model 
broke down. Whatever the explanation, it was recog- 
nized that the representation of physico-mathematical 
equations could no longer be anything picturable. Thus 
no description of actuality answers to the new physics. 
This fact left scientists in a quandary as to how to explain 
what scientific 'concepts' meant. A whole new flood of 
scientific-philosophical explanations was poured forth. 
In general these were divided into two classes: the 
mentalistic interpretations and the operational interpre- 
tations. 

The mentalist view has been made popular through 
the work of Eddington and Jeans. According to them, 



84 WHAT SCIENCE REALLY MEANS 

science is concerned with the mental constructions on an 
objective reality which is entirely unpicturable and, in 
fact, unknowable in esse, but which is represented best 
by mathematical symbols. Their eventual conclusion as 
to the substratum of physical reality is that it is "mind 
stuff." This, as Eddington says, 9 is not exactly mind and 
not exactly stuff, since it is not identifiable with individual 
consciousness nor spread out in space and time. 

Jeans, taking mathematics as the nearest human formu- 
lation of reality, decides that the stuff of the world is 
mathematical thought, but again not thought in any 
individual's mind, but rather in the mind of God. 
Clearly both men believe that science is concerned with 
finding not the what of reality but the how, and that this 
can be represented mathematically in terms of symbols, 
which to Eddington are "pointer readings" and to Jeans 
pure mathematical symbols. The merit of these theories 
is that they point to the extreme abstractive character 
of the scientific subject-matter. They have incidentally 
shown that the scientific 'picture* cannot ever be com- 
prehended in terms of common-sense actuality. 

Despite this merit, however, the total effect of denying 
the objectivity of the scientific subject-matter has brought 
the investigator back into the objective scientific field. 
'Mind-stuff/ as set forth by Eddington and Jeans, turns 
out in the end not to be dependent on the mind. If it 
serves any purpose to call this 'mind-stuff/ when it is 
neither mind nor stuff, well and good, but interpreted 
in the light of other passages in Eddington's books, it 
must be insisted that he does seem to mean both mind 
9 The Nature of the Physical World, p. 276. 



MODERN MISCONCEPTIONS OF EMPIRICISM 85 

and stuff. Thus the mental is confused with the physical, 
with the added assumption that the mind never really 
knows the physical. From this hash of subjective and 
objective idealism, it is small wonder that scientists 
should rebel, confirmed in their old opinion that 
philosophy is time wasted over words, and that the life 
of science consists in doing things. The mentalist inter- 
pretation plays havoc with empiricism, since according 
to it observed phenomena are only the mental interpre- 
tations of an unknowable reality underlying the pheno- 
mena. This seems to leave no basis for agreement other 
than private opinion; and from the scientific point of 
view is its greatest source of repugnance. 

The most cogent argument against the mentalist view 
is to show that it resolves nothing. The determination to 
call all things stuff of the mind is to put them all on a 
parity. But science is known for the distinctions it makes 
and not for the names which it can apply equally to all 
phenomena. Mind-stuff, like any term which can be 
equally applied to all things, leaves the theory of science 
exactly where it was. 

THE LOGICAL POSITIVIST VIEW 

From out this maze of metaphysical theory, the scientists 
have sought to save themselves by the discovery and 
embrasure of that philosophy of science which seems to 
contain the least metaphysics and to permit scientists to 
confine their speculations and efforts to the empirical. 
Often called operationalism by scientists, this theory is 
known more generally as logical positivism. 
The position has been put forward and systematically 



86 WHAT SCIENCE REALLY MEANS 

formulated by the logical positivists of the Vienna 
Circle: Wittgenstein, Schlick, Reichenbach, Waismann, 
Neurath, and Carnap. These men are by profession 
philosophers whose chief interest is science, but they are 
all violently anti-metaphysical. They trace their trend of 
thought back to Comte and Mach, but assume a much 
more radical position. Logical positivism asserts that all 
metaphysical questions are meaningless, e.g. the question 
of whether the nature of the physical world is mind- 
stuff or matter or subjective interpretation. All problems 
which cannot be verified in experience come under this 
category. 

Most propositions and questions, that have been written 
about philosophical matters, are not false, but senseless. We 
cannot, therefore, answer questionsof this kind at all but only 
state their senselessness. 10 

And Carnap presents exactly the same point of view. 11 
His explanation is as follows : 

But this question [the reality of the physical world] has no 
sense, because the reality of anything is nothing else than a 
possibility of its being placed in a certain system . . , and 
such a question only if it concerns elements or parts, not if it 
concerns the system itself. 12 

Every science must express itself in the language of 
physics, the "protocol language." 

In our discussions in the Vienna Circle we have arrived at 

I Wittgenstein, Tractatus Logico-Philosophicus, 4.003 . 

II Carnap, The Unity of Science (London, 1934, Kegan Paul), p. 21. 
12 Carnap, Philosophy and Logical Syntax (London, 1935, Kegan 

Paul), p. 20. 



MODERN MISCONCEPTIONS OF EMPIRICISM 87 

the opinion that this physical language is the basic language 
of all science, that it is a universal language comprehending 
the contents of all other scientific languages. . . . Dr. 
Neurath, who has greatly stimulated the considerations which 
led to this thesis, has proposed to call it the thesis of 
physicalism. 1 * 

For example, psychology would reduce to behaviour- 
istic psychology; biology to descriptions and terms which 
reduce to something perceptible and not to non-empirical 
entities; and so on. 

This school accepts logic without question and uses it 
to reinforce its positivism. The logical positivists say that 
logical analysis is the only real problem of philosophy. 

The function of logical analysis is to analyse all knowledge, 
all assertions of science and of everyday life, in order to make 
clear the sense of each assertion and the connections between 
them. One of the principal tasks of the logical analysis of a 
given proposition is to find out the method of verification for 
that proposition. 14 

For example, this school would say that the logical 
analysis of the concept, metabolism, shows that it does 
not refer to a mysterious non-empirical entity but to an 
observable process which must be specified in terms of 
physical measurement. Thus to discuss what metabolism 
is in itself is meaningless. The Vienna Circle's reliance 
on logic and the doctrine of physicalism or the "protocol 
language" which is applicable to all science, inevitably 
led to the doctrine of the unity of science. 

13 Carnap, Philosophy and Logical Syntax, p. 89. 

14 Ibid., pp. 9-10 (italics ours). 



88 WHAT SCIENCE REALLY MEANS 

Because the physical language is thus the basic language 
of Science the whole of Science becomes Physics. 15 

If we have a single language for the whole of science the 
cleavage between different departments disappears. Hence the 
thesis of Physicalism leads to the thesis of the unity of Science. 1 * 

There is a tendency on the part of some members of 
the Vienna Circle to emphasize the logical side of logical 
positivism. It is possible to endorse at least some of the 
utterances of Moritz Schlick, which, in so far as they are 
valid, seem to us to depart from the position of positivism. 
Schlick says, for instance, that 

the question of meaning has nothing to do with the psycho- 
logical question as to the mental processes of which an act 
of thought may consist. 17 

This denial of the primacy of sense-experience is not in 
keeping with the radical empiricistic view of most of 
the logical positivists. But Schlick ventures even farther 
than this in his defence of logic. 

It must be emphasized that when we speak of verifiability 
we mean logical possibility of verification, and nothing but 
this. 18 

The truth simply is that such an assertion contradicts the 
postulates of the modern logical positivistic school, and 
is much more conformable with the realistic view, which 
will be examined on page 96. 

Logical positivism may be summarized under two 
headings, the logical and the empirical. 

15 Catnap, The Unity of Science, p. 97. 16 Ibid., p. 96. 

17 The Philosophical Review, vol. xlv (1936), p. 355. 

18 Ibid., p. 349. 



MODERN MISCONCEPTIONS OF EMPIRICISM 89 

The logical position states the valuable truism that 
logical analysis involves the relations of parts of a system 
to the whole system, and has nothing to say about the 
system as a whole or about anything beyond that 
system. The analysis of the building bricks, which may 
happen to be part of a house, into their chemical con- 
stituents has nothing to say about brick or about house. 
And to bring such questions into the logical analysis is 
irrelevant, or, in terms of the positivist in this connection, 
"meaningless." But the statement that such questions are 
irrelevant at this level of analysis certainly does not 
imply that they are altogether irrelevant to the whole 
of knowledge, or that they are meaningless. Meaning- 
lessness in one connection does not imply meaningless- 
ness in another. Neither is the question of the reality or 
unreality of the physical world meaningless, even though 
it is irrelevant to physics qua physics. The positivists have 
done a service and a disservice: a service by calling 
attention to what should be a platitude, and a disservice 
by holding down speculation to analysis. 

The empirical position of logical positivism asserts that 
whatever cannot be verified in experience is meaningless. 
Stated in this manner, the proposition is a truism but one 
which has given rise to a vicious notion, namely, that 
what has not been done cannot be done. Unfortunately, 
the positivists mean by 'cannot/ 'has not/ And this 
entitles them to throw out as meaningless all speculations 
which concern unsettled problems. The erection of a 
failure into a principle serves only to insure the con- 
tinuance of the failure. The history of science is full of 
examples of the verification of that which was at one 



90 WHAT SCIENCE REALLY MEANS 

time thought to be permanently unverifiable. 19 In 
ancient times the distances of the stars from the earth 
was deemed unverifiable. But if on the positivist principle 
the problem had been thrown out as meaningless, no 
verification would ever have been made. Indeed the whole 
advance of science has been that of verifying what was 
once pure speculation. The problem of the nature of 
beauty, for instance, would be considered by the logical 
positivists a meaningless question. Perhaps it is. But 
certainly no one has ever been able to demonstrate con- 
clusively its meaninglessness. If we should proceed on 
this assumption, the problem would come to an end and 
be dropped from speculation. If, however, we should 
proceed on the opposite assumption that it might have 

19 To make the positivistic assertion that this or that cannot be 
done is contradictory to positivism, since it represents reasoning which 
has gone far beyond the empirical facts. Quite an imposing list could 
be drawn of accomplishments which had been formerly proved to 
be 'impossible of accomplishment.' For instance, Aristotle said that 
"one may be satisfied that there are no senses apart from the five" 
(On the Soul, book iii, i) yet modem physiological psychology has 
discovered others. "Legendre said of a certain proposition in the theory 
of numbers that, while it appeared to be true, it was most likely 
beyond the powers of the human mind to prove it ; yet the next 
writer on the subject gave six independent demonstrations of the 
theorem. Auguste Comte said that it was clearly impossible for 
men ever to learn anything of the chemical constitution of the fixed 
stars, but before his book had reached its readers the discovery which 
he announced as impossible had been made" (C. S. Peirce, Collected 
Papers, 6.556). "We [wrote J. Muller] shall probably never attain the 
power of measuring the velocity of nervous action, for we have not 
the opportunity of comparing its propagation through immense space, 
as we have in the case of light" (J. C. Fliigel, A Hundred Years of 
Psychology, p. 89). But a few years later, as Fliigel points out, the task 
was accomplished by Helmholtz, who had been one of Miiller's pupils. 



MODERN MISCONCEPTIONS OF EMPIRICISM 91 

meaning, some verifiable knowledge might be discovered 
which the positivist would then accept as meaningful. 
We can therefore allow the statement that whatever 
cannot be verified is meaningless, but it will not make 
any difference to the procedure of science except as a 
caution against unbridled speculation. 

Logical positivism helps to clear up certain logical 
misunderstandings about science, but it does not con- 
stitute a programme for scientific activity. And its 
physicalistic understanding of empiricism is an insufficient 
formulation. For science to accept entire the philosophy 
of the Vienna Circle would be equivalent to signing its 
own death-warrant. Empiricism is something broader 
than the caution to hold science down to the sensory. 

THE OPERATIONALIST VIEW 

The second group of modern positivists whose views on 
empiricism we have to consider is not composed of pro- 
fessional philosophers but of physical scientists, who have 
in a sense stepped out of their role as physicists to con- 
sider the theoretical nature of the scientific subject- 
matter. Prominent among them are Lenzen 20 and 
Bridgman, 21 Heisenberg and Dirac. In general, the 
position of Heisenberg and Dirac is expressed by that of 
Lenzen. 

In agreement with the empiricistic point of view my 
theory of science assumes a subjectivistic criterion of reality. 
A physical body is a class of aspects which are or can be 
given to some mind. In general one may say that the criterion 

20 The Nature of Physical Theory. 

21 The Logic of Modern Physics. 



92 WHAT SCIENCE REALLY MEANS 

of the reality of aspects is that they be possibilities of experi- 
ence. . . . The objectivity of the physical order is grounded 
in correlations between aspects given to different minds. 22 

The derivation from Mach, which Lenzen freely admits, 
is obvious in the above passage. "Aspects" are the same 
as Mach's "sensations," and they both turn out to include 
more than sensations, namely, "possibilities of experience." 
This is the same question-begging device employed by 
Mach. 23 

But let us read a little further. 

All entities of physical science can be characterized in terms 
of experienceable aspects. 24 

How we are to distinguish between what is "experience- 
able" in advance ot experience and what is not, is not 
suggested. Thus Lenzen concludes by accepting positivism 
and seeing that it implies all that subjectivism implies. 

... the positivistic criticism is that a subjectivistic criterion 
should be employed. 25 

Let us see which way his theory, that all the entities 
of physical science can be characterized in terms of 
"experienceable aspects," leads. It led with Mach and 
Ostwald to the rejection of molecules and atoms as 
fictions because these had not yet been experimentally 
observed. It leads with Lenzen to the acceptance of 
microscopic entities not as fictions but as realities, because 
their existence is now inferable from observation. Thus 
the same premises accepted by Mach and Lenzen lead 

22 Lenzen, op. cit., p. 6. 23 See above, p. 80. 

24 Lenzen, op. cit., p. 8. 25 Ibid., p. 10. 



MODERN MISCONCEPTIONS OF EMPIRICISM 93 

them to contradictory conclusions. This confusion well 
illustrates that much can exist which is not at any given 
time experienced, and it also exhibits the question- 
begging device of "experiences We" which offered no 
help to Mach. As a matter of fact, none of the entities 
of physical science are aspects of experience per se, though 
aU are inferred from experience. 

That Heisenberg and Dirac agree with positivism, 
Lenzen has noted. For instance, he quotes Dirac, 

A fraction of a photon is never observed, so that we may 
safely assume that it cannot exist. 26 

Whether a fraction of a photon can exist or not we do 
not know, but certainly we can say that the fact that it 
has never been observed is no proof of its non-existence 
any more than the fact that the planet Pluto had not 
been observed in 1900 proved its non-existence. Did the 
heavy isotope of hydrogen come into being in 1935? 
This kind of nonsense is just the sort of thing which kills 
off speculation as fast as it is attempted, since science has 
always gone on the assumption that there must be 
entities and processes to be discovered which nobody has 
yet experienced. 

Let us now turn to the work of P. W. Bridgman, 
another scientist whose theory of science has had much 
influence in America. Bridgman admits that his work is 
derived largely from Clifford, Stallo, Mach, and 
Poincare, and he brings their theory to bear on the new 
concepts of physics. Particularly noticeable is the deriva- 
tion from Poincare. 27 He has taken the quasi-objective 

28 Lenzen, op. cit., p. 10. 27 See above, p. 81. 



94 WHAT SCIENCE REALLY MEANS 

side of positivism which makes physical concepts not the 
summaries of sensations but the performances of ex- 
periments. This is "operationalism." 

In general, we mean by any concept nothing more than a 
set of operations: the concept is synonymous with the corre- 
sponding set of operations , 28 

Bridgman does not admit any validity to concepts other 
than as summaries of operations. This insistence on 
operations seems to satisfy the demand of science to be 
empirical, and seems, moreover, to hold science down to 
the laboratory and to do away with all metaphysical 
speculation. But it really cuts the ground from under 
empiricism and is incurably subjective, since it ends by 
telling science that its concepts do not refer to entities 
but to the perception of scientists. 

That the subjectivity of the observer must on this view 
enter into the operations observed, to an indeterminable 
degree, is admitted by Bridgman when he says that 

it is evident that the nature of our thinking mechanism 
essentially colours any picture that we can form of 
nature. . . , 29 

Thus Bridgman not only denies the objectivity of the 
entities of science but he confounds the issue by insisting 
upon a subjective criterion while admitting the existence 
of a dualism whereby the mind contributes part and the 
operations contribute part. This leads to an utter distrust 
of rationality, even to the denial of the validity of logic. 
Bridgman tells us that 

28 Bridgman, The Logic of Modern Physics, p. 5. 

29 Ibid., p. xi. 



MODERN MISCONCEPTIONS OF EMPIRICISM 95 

our conviction that nature is understandable and subject to 
law arose from the narrowness of our horizons, and ... if 
we sufficiently extend our range we shall find that nature is 
intrinsically and in its elements neither understandable nor 
subject to law. . . . 30 

If nature is not subject to law, then the whole of science 
is a fruitless proceeding. What, then, are the discoveries 
of science, and why do contemporary scientists whose 
horizons have recently been broadened continue to look 
for uniformities in nature? The mere fact that physics 
has so far discovered no way to study the occurrences 
within the atom except in statistical computations of 
results is used as an argument to show that causality does 
not apply to the sub-microscopic world, and indeed that 
it does not apply at all, i.e. causality is not in any way a 
principle of nature. Surely to erect a failure into so 
general a principle with which to contradict all prior 
assumptions of science is a ridiculous attempt. 

The same criticism which applies to all positivists 
applies to Bridgman. There is exhibited the failure to 
distinguish between the fact of perception and that which 
is perceived; between the operations or experiments 
which reveal laws and the laws thus revealed; between 
the observed and the existence which is covered by the 
term * observable/ In attempting to make empiricism the 

80 "The New Vision of Science" in Harper's for March 1929. In a 
later work this is contradicted by Bridgman : "Chance has no meaning 
except in a setting of order/' The Nature of Physical Theory, p. 123. 
In the latter work, in which Bridgman brings his position up to date, 
there is so much confusion and contradiction that further refutation 
is unnecessary. 



96 WHAT SCIENCE REALLY MEANS 

whole of scientific method, the very idea of empiricism 
is rendered incomprehensible by the positivists, who must 
eventually refer it to the subjective category mental 
classification. The end accomplished by the positivists is 
exactly the opposite of their aim, which is to keep science 
empirical and clear of metaphysics. The result is deadening 
to all scientific advance. 

THE REALIST VIEW 

Mentalism was unsatisfactory to the scientists because, 
although it allowed objective reality to the objects of 
scientific investigation, it denied reality to phenomena 
and thus seemed to negate the validity of empiricism. 
Positivism was unsatisfactory to the scientists for the 
opposite reason, namely, because although it allowed 
reality to the phenomena observed, and thus to empiri- 
cism, it denied reality to the objective physical world, 
and thus seemed to negate the scientific search for the real, 
making its discoveries at last a subjective affair. 

Among modern scientists there is a group whose 
theory of science is neither mentalist nor positivist but 
who believes, on the contrary, that the concepts of science 
refer to real conditions, that causality holds in the uni- 
verse, and that therefore there is such a thing as law 
independent of our mental generalizations. The present 
gaps in detecting causality in sub-microscopic regions are 
attributed by them to ignorance of the factors involved 
and not to a basic indeterminism. Neither do they make 
the attempt of Eddington and Heisenberg to generalize 
from the sub-microscopic level to the macroscopic level, 
e.g. to prove or disprove free will. To quote Einstein, 



MODERN MISCONCEPTIONS OF EMPIRICISM 9? 

The belief in an external world independent of the per- 
ceiving subject is the basis of all natural science. 31 

But for Einstein this reality is not for ever hidden from 
view but can be known to the human mind, which grasps 
it through mathematical concepts. 

In a certain sense, therefore, I hold it true that pure thought 
can grasp reality, as the ancients dreamed. 32 

Max Planck, the discoverer of the quantum, agrees 
with Einstein in rejecting positivism and holding fast to 
the validity of the principle of causality as based upon 
an independent and real physical world. Even such an 
extreme example as Heisenberg's Principle of Inde- 
terminacy, which has been used by philosophers of 
science to prove the non-existence of causality, is seen 
by Planck to be fundamentally causalistic. Regarding 
this principle, he says, 

Here the causal principle is not applicable. That is to say, 
we cannot estimate simultaneously both the velocity and 
position in space-time of a particle and say where it will be 
a moment hence. But this does not mean that the causal 
sequence is not actually verified objectively. It means that we 
cannot detect its operation. . . , 33 

And in regard to the positivist position, Planck is very 
strenuous in his denial; pointing out that science is con- 
cerned neither with the accidental, the contingent, nor 
the observable, i.e. not with sensations but with the 
reality which can be found by their help. 

31 The World as I See It (New York, 1934, Covici-Friede), p. 60. 
82 Ibid., p. 37- 

38 Planck, Where Is Science Going? p. 33 (George Allen & Unwin 
Ltd.). 

G 



98 WHAT SCIENCE REALLY MEANS 

That we do not construct the external world to suit our 
own ends in the pursuit of science, but that v ice versa the 
external world forces itself upon our recognition with its own 
elemental power, is a point which ought to be categorically 
asserted again and again in these positivistic times. From the 
fact that in studying the happenings of nature we strive to 
eliminate the contingent and accidental and to come finally 
to what is essential and necessary, it is clear that we always 
look for the basic thing behind the dependent thing, for what 
is absolute behind what is relative, for the reality behind the 
appearance and for what abides behind what is transitory. In 
my opinion, this is characteristic not only of physical science 
but of all science. 34 

Not only is this understanding of science recognized 
by a few physicists, but at least one biological scientist 
states the same position unequivocally. 

From the things encountered in the material world, whether 
atoms or stars, rocks or clouds, steel or water, certain qualities, 
such as weight and spatial dimensions, have been abstracted. 
These abstractions, and not the concrete facts, are the matter 
of scientific reasoning. The observation of objects constitutes 
only a lower form of science, the descriptive form. Descriptive 
science classifies phenomena. But the unchanging relations 
between variable quantities that is, the natural laws, only 
appear when science becomes more abstract. 35 

This version ot empiricism in science is not shared at 
present by many scientists. Most scientists prefer the 
positivistic point of view, which we have been criticizing. 
But even with Planck, Einstein, and Carrel the rejection 

34 Planck, Where is Science Going? p. 198. 

35 Alexis Carrel, Man the Unknown, pp. i and 2. 



MODERN MISCONCEPTIONS OF EMPIRICISM 99 

of positivism and the assertion of the reality of the 
entities of science is based upon happy intuitions and is 
more of a hope and a faith than a demonstrable belief. 
There is therefore some force to the point made by 
Eddington 36 that the present stage of physical science leads 
neither to an acceptance nor to a rejection of causality, 
and that therefore it is held by these men as a pure theory 
and cannot employ present-day physics as a basis for its 
proof. 

'Happy intuitions' are not enough. The theory of 
science must be understood by the scientists abstractly 
and theoretically, in a form as universally acceptable as 
the findings of science itself. 

We have already pointed out that the theory of science 
must he outside the scientific field proper, and that one 
cannot make use of scientific findings to prove the theory 
by which such findings can be connected up with the 
rest of existence. The reality of the physical world and 
the existence of causality are thus not questions which 
can be resolved by the mere appeal to physics or to any 
other special science. Recourse must be had to philosophy. 
The history of science reveals that the practice of science 
has not been at one with the theory. The fact that reason 
and experiment have both been employed wherever 
valid science has taken root may be contrasted with the 
fact that throughout the history of modern science 
scientists have unfortunately believed these two prin- 
ciples to be opposed. They have clung to empiricism for 
fear of going off into metaphysical quiddities. The re- 
futation of positivism is easy, but the true definition of 

36 See Eddington, New Pathways in Science, especially p. 297 fF. 



ioo WHAT SCIENCE REALLY MEANS 

the place of empiricism in science requires more. It 
requires an analysis of logic and empiricism as practised 
in science, to demonstrate their essential reconcilability, 
and thus give rational justification to what is now only 
a hope and a faith. In the next chapters we shall turn to 
the fulfilment of this task. 



CHAPTER V 

NATURE OF THE FIELD OF SCIENTIFIC 
INVESTIGATION 

For modern scientists, as for Plato, IDEAS are 
the sole reality. 

A. CARREL 

WE have come to the end of our brief survey of the 
history of empiricism, in practice and theory. It has 
been seen that the controversy over the question of 
empiricism centres around a single comprehensive 
issue. We shall now have to separate this issue from the 
various historical figures who have taken sides with 
regard to it. This will entail leaving history and con- 
centrating upon the abstract problem. 

WITH WHAT IS THE CONTROVERSY CONCERNED? 

The various schools and traditions whose doctrines we 
have exhibited are in effect so many answers to one 
question, namely, what is the true subject-matter of 
science ? Science itself can restrict its abstract interest to 
the problem of method, whether this be logical or ex- 
perimental. But philosophies of science must be con- 
cerned with something more than method. They must 
be concerned with subject-matter. Even those abstract 
speculators who suppose that their preoccupation is only 
with method are mistaken. For what is a method, if not a 
step toward something else, a means of achieving an 
end? Thus science is more than method, even though 



102 WHAT SCIENCE REALLY MEANS 

strict scientific analysis may not have to take this fact 
into consideration. 

Thus the three schools which we have examined, the 
positivists, the mentalists, and the realists, all primarily 
direct their attention to the nature of the field of scientific 
inquiry. The positivists believe that they can make the 
method of science itself into the subject-matter of 
science. But even this is an attempt to define the subject- 
matter. The mentalists find the nature of the scientific 
subject-matter 1 in mysterious noumena, an unknowable 
something lying behind the field of sensory phenomena. 
The realists find the nature of the scientific field in a 
directly knowable set of relations, which phenomena 
only exemplify. Let us take some familiar entity of 
science and show how each school would regard it. 

The physical law of action and reaction is a scientific 
entity. The question then is : what is the status of its 
reality ? To this question the answer of each of three 
schools is different. For the positivists, the reality of this 
law resides only in the actual or observed phenomena. 
As to the reality of the law itself, they would deny its 
existence as an independent entity and claim for it the 
status of a mental concept. For the mentalists, the reality 
of this law resides in its existence as a mental concept 
derived from real but unknowable objective conditions 
of nature. For the realists, the reality of this law resides 
in real and knowable objective conditions of nature. 
The law is thus a reality independent of both subject 
and object, independent of the subject since existing 

1 The mentalists seem to have confined their remarks to the science 
of physics and the nature of the physical world. 



NATURE OF FIELD OF SCIENTIFIC INVESTIGATION 103 

without its knowledge, and independent of the pheno- 
mena because existing without such exemplification. 
Thus the understanding of such a law* or scientific entity 
as the law of action and reaction differs in all three cases. 

One clear fact must be admitted at this point. This is 
that physicists, though they hold different philosophical 
views concerning the reality of the physical subject- 
matter, seem to function equally well as physicists. For 
instance, Heisenberg, Eddington, and Planck seem to 
have no disagreements over each other's work as 
physicists. Their disagreement comes only with the 
interpretation of their work. Does this mean, then, that 
the question of the reality of the scientific subject-matter 
is meaningless? Certainly it does not seem to have 
affected the procedure of the science of physics. It is just 
this point which makes the scientists so professionally 
disdainful of metaphysics. 

To this question of what difference does it make there 
are many answers. First of all, procedure does follow from 
philosophy. When the physicists hold one philosophy 
and practise the procedure that would follow from 
another philosophy, this merely means that they are not 
holding the philosophy they think they are holding. 
Newton could not possibly have leaped from terrestrial 
to celestial mechanics without the belief in the uni- 
versality of natural law, which certainly is not to be 
found in any analysis of the motions of bodies. From a 
purely analytic point of view, there is no warrant for 
such a theory. Again, without a belief in the continuity 
of natural phenomena, no one would ever have tried to 
find the proper equations for the cicatrization of wounds. 



104 WHAT SCIENCE REALLY MEANS 

In other words, analysis is not the whole of scientific 
procedure, although nothing unanalysed can be called 
scientific. 

Plainly any science must start by seeking isolatable 
systems to be analysed, and these systems cannot be 
found by analysis. Granting it to be true that the analysis 
is not affected by the interpretation put upon the meaning 
of the isolated system, it is still true that without some 
meaning for the total system, no new system could be 
found. Certainly the anatomical analysis of the spleen is 
unaffected by the function of the spleen in the animal 
constitution; but until the relation of the spleen to the 
whole organism is better understood, this analysis will 
not only be largely meaningless but also undirected. 
Thus what does not affect analysis directly does affect 
the understanding of that analysis and, indirectly, the 
analysis itself. An example may be taken from common 
experience. A chair could be analysed without the 
analyst knowing its use or purpose. But certainly such 
analysis would be entirely without value and without 
interpretation. What purpose would be served by 
specifying the weight-bearing properties of the legs 
unless in the light of the use of the whole chair ? 

If physicists came to the conclusion that analysis of 
systems now known is the whole of physical science, there 
would be no more systems to analyse. In other words, 
with the wrong philosophy, science cannot keep on 
developing, but must stagnate. In so far as physical science 
has followed the wrong philosophy, it probably has, 
despite its brilliant success in the past, been somewhat 
retarded. It will certainly be brought to a halt in the 



NATURE OF FIELD OF SCIENTIHC INVESTIGATION 105 

future unless its first principles are straightened out. About 
other sciences we can speak with more confidence. The 
far less successful biological sciences owe their partial 
failure and retardation to a timidity of theory which 
lays the injunction upon scientists only to analyse. The 
positivistic or 'empirical' creed of the social sciences has 
strangled them in gestation. So vicious has been the effect 
of the wrong philosophy in the social sciences that, at 
least in some quarters, even the possibility of exact social 
science is denied. 

Besides the crippling of science itself, there is the large 
and unavoidable question of the place of science in the 
scheme of things. For instance, what of science with 
regard to society ? Surely on the answer to this question 
the future of science will largely depend. And unless 
science can answer the question as to what it is concerned 
with, it may be challenged by society and prove unable 
to defend itself. Finally, the scientists themselves are 
something more than scientists: they are human beings 
who require some answer to the question of what they 
are spending their lives doing. In the course of every 
laboratory day, the question is bound to occur to the 
scientist of the meaning of his activity, even though he 
dismiss such considerations as irrelevant to the imme- 
diate business at hand. But the question cannot be dis- 
missed for ever and is bound to recur to every human 
being, until he answer it at least to his own satisfaction. 
If the answer be that there is no answer, i.e. that it is a 
meaningless business, he could not go on in a whole- 
hearted way. It is at least arguable that the great advance 
in physical science in the past three hundred years has 



io6 WHAT SCIENCE REALLY MEANS 

been activated by the belief that this is the best way to 
find out the nature of reality. 

We may conclude by saying that scientific method 
depends upon the philosophy of science. The future of 
science depends upon the philosophy it adopts. Therefore 
the sooner the scientists become aware of this condition, 
the better it will be for the welfare and development of 
science. 

THE INQUIRY INTO SCIENTIFIC OBJECTS 

We have seen that the philosophical problem of the 
nature of science cannot be dodged by science. This 
problem is the nature of the objects with which scientific 
analysis works. Let us attempt to determine what their 
nature is by examining them under their various names. 
In attacking this problem no mystical or complex meta- 
physical theory or discussion need be introduced. The 
nature of scientific objects must be, like the nature of 
anything else, defined by what is implied by them. The 
technique of philosophical analysis does not differ essen- 
tially from that of scientific analysis, though it operate 
from a different level. 

Scientific objects are known variously, and sometimes 
interchangeably, as entities (e.g. a molecule), concepts 
(e.g. entropy), processes (e.g. radio-active disintegration), 
events (e.g. an electromagnetic force field), and laws 
(e.g. Avogadro's Law). These may all be described as 
scientific objects. It is at once obvious that some of the 
terms are interchangeable. In order to examine their 
nature let us start by finding out and discarding what 
they are not. Are scientific objects mental ? No, since by 



NATURE OF FIELD OF SCIENTIFIC INVESTIGATION 107 

mental is meant something which depends for its 
existence exclusively upon the mind. All our scientific 
objects give every evidence of existing, and exerting 
influence, indifferently as to whether they are perceived 
or thought about or not. Thus it would be idle to call 
them mental. The conditions which are described as 
entropy continue whether there is consciousness of them 
or not, and indeed we are assured by the astronomers 
that entropy will go on long after animal life has become 
impossible on a rapidly cooling planet. 

The same independence of knowledge holds for 
Avogadro's Law: under the same temperature and 
pressure, equal volumes of gases continue to have equal 
numbers of molecules, regardless of whether we know 
about this fact or not; and this condition will continue 
to prevail even if in the future it is forgotten. Perhaps the 
notion that scientific objects are mental has arisen from 
the recognition of the fact that in so far as these conditions 
are known they are known. But why confine this to 
scientific objects when the same is true of an elephant 
in the zoo ? We have already shown that when scientific 
objects are dubbed mental, the implication is that they 
depend for their existence upon the mind, which is 
simply not true. 2 Thus the concept of entropy is mental 

2 If the old subjective argument be invoked that we cannot know 
anything about anything when we are not knowing it, and that there- 
fore we cannot assume the existence of anything when we are not 
knowing it, the answer is that it is irrefutable but also undemonstrable. 
It is, moreover, incredible and fruitless. Whoever chooses to believe 
that radio-active disintegration ceases when it is not in any human 
consciousness, will have to take the same position with regard to the 
elephant. 



io8 WHAT SCIENCE REALLY MEANS 

in so far as it is a concept, but entropy in so far as it 
refers to conditions which are not mental. Similarly 
with the concept, elephant. 

Mentalism, however, is generally put forth as a sort of 
objective mind-stuff theory. The 'stuff' of physics is said 
to consist of mind, perhaps thoughts, in the mind of 
God. But does this theory help any more than the other 
to explain what scientific objects are? Let us accept it 
and see where it leads. The mind-stuff called sulphuric 
acid analyses into the mind-stuffs called hydrogen, 
oxygen, and sulphur, which in turn analyse into mind- 
stuffs called electrons, protons, etc. It is evident from 
this analysis that the term mind-stuff is being carried for 
nothing, and since it appears on both sides of each equa- 
tion, can be cancelled out with no loss to the knowledge 
of what is involved. 3 Our knowledge of sulphuric acid 
is neither helped nor retarded by the term mind-stuff. 
An explanation which makes no difference is not an 
explanation but a restatement, more or loss clumsy, of 
the original problem. Unless differentiae can be shown 
to arise from the distinctions made, they are not worth 
making. Thus to say that the nature of the physical 
world is mental in either the subjective or objective 
sense of the term, is to use 'mental' to describe every- 
thing, and therefore to rob it of any sense it may have. 
It is also to leave the problem of the nature of scientific 
objects just where it was. 

3 Let mG = the mind of God. Then 

mG H 2 SO 4 -> mG SO 3 + mG H 2 O 

It is obvious that dividing through by mG will give an equation which 
yields the same result. 



NATURE OF FIELD OF SCIENTIFIC INVESTIGATION 109 

It has been shown that scientific objects are not, in the 
usual sense of the term, mental; and if called mental 
in the unusual sense of mind-stuff, the proposition is 
nugatory. We have now to consider whether scientific 
objects are actual. By 'actual' is meant phenomena which 
are experienced, with all their affects and values. In 
other words, are the objects of science to be wholly 
identified with the common-sense objects of our daily 
observation, such as red apples, sunsets, parades, water, 
turtles ? Plainly, science is not primarily concerned with 
such common-sense objects, and does not rest content 
with them. Science always abstracts certain qualities 
when it experiments with common-sense objects. Thus 
it was not the apple but the apple's fall which interested 
Newton; and it is not the wetness of water or its 
potability which interests the chemist. 

But the inquiry of science goes beyond even the 
abstractions of qualities from particular objects. For 
instance, it is not even the apple's fall which is ultimately 
interesting to the scientist who works with mechanics, 
but the relations of mass, distance, and time, which the 
fall of the apple exemplifies. It is not the particular 
length of a bar of metal which concerns the physicist, 
but relative dimensions. The same is true of biology, 
though not so obviously. The zoologist who examines 
the relation of the temperature of turtle blood to turtle 
heart-beat is not the least concerned with the awkward- 
ness of the turtle or the edibility of turtle meat or the 
decorative value of the shell. In other words, the par- 
ticular common-sense turtle means nothing to the 
zoologist, who is employing certain abstractions from a 



no WHAT SCIENCE REALLY MEANS 

particular turtle only because he believes on sufficient 
evidence that he has got hold of a fair sample of heart- 
beat and temperature of the species, turtle. Thus again 
science proceeds from the common-sense phenomena to 
the abstractions of certain qualities from such phenomena, 
to generalizations about the relations of such abstract 
qualities, or to what are called laws. 

Those qualities which science abstracts tend to become 
those which are commensurable. This is the ideal of 
every science, but at early stages qualitative differentiation 
is abstracted. In general, we may say that scientific 
abstractions proceed from qualities to quantities. 

At this stage we reach entities or laws or processes or 
concepts which can hardly be said to be phenomena, 
though they be reached in and through phenomena 
or by abstraction from phenomena abstractions many 
times abstracted. This is why mere description or classi- 
fication is the most rudimentary form of exact study; it 
stops at the first stage of abstraction. We arrive at the 
conclusion that scientific objects are not actual, even 
when they are exemplified in actuality. The scientific 
molecule is not identical with the actual molecule, even 
admitting that such an exemplification could be demon- 
strated. Entropy is not understood by science as the 
actual disbursement of energy; degradation goes on at 
any moment, but is only an exemplification of entropy. 
Radio-active disintegration may be observed to take place 
over a period in radium, uranium, etc., but the process is 
not confined to detectable occurrences. Electromagnetic 
fields are studied independently of actual fields set up, 
e.g. mathematically. And Avogadro's Law is merely 



NATURE OF FIELD OF SCIENTIFIC INVESTIGATION in 

exemplified by any gas under pressure, and is a state- 
ment of conditions which do not become dissipated with 
the dissipation of the gas. These arc the objects of science, 
and as such are hidden from common observation as 
they occur. They are empirical because they are detectable 
in and through actuality by trained observers; they are 
non-sensory and have no dependence upon phenomena, 
i.e. phenomena depend upon them. It is for this reason 
that experiment is used in science to prove or disprove 
theories or laws. 

SCIENTIFIC OBJECTS ARE FUNCTIONS 

We have seen that scientific objects are essentially 
neither mental nor actual, and that the end of scientific 
investigation concerns the finding of abstract relations. 
It proceeds from phenomena to abstractions from 
phenomena, to abstractions concerning relations between 
abstractions. The relations between abstractions can be 
best understood as representing constant functions, the 
invariant relations between variable quantities. Functions 
are therefore the objects of scientific inquiry. They are 
the scientific objects. And this is seen as soon as we dis- 
card the pictorial or mythological tags by which they 
are ordinarily represented. How can we best understand 
without reference to the formulations of science what a 
function is ? Function is defined 4 as "that power of acting 
in a specific way which appertains to a thing by virtue 
of its special constitution." The function of anything, 
then, is its necessary relation to something else. It is what 
is essentially true about a thing so long as it is a thing. 

4 The Century Dictionary. 



ii2 WHAT SCIENCE REALLY MEANS 

If, for example, we say that the function of a lead-pencil 
is to write in a certain way on paper, we are saying two 
things: (i) that it must be composed of something 
capable of performing this function; and (2) that it is 
potentially capable of acting in a certain way. Thus 
however variable may be the constitution of a lead-pencil, 
and however variable its use, the function between the 
constitution and the use is constant and necessary. 

The functions of a right-angled triangle are studied in 
trigonometry. They are the necessary conditions to which 
any right-angled triangle must conform to be a right- 
angled triangle. 



Hypotenuse 

is a statement of an invariant relation between variable 
quantities, which lays no restrictions upon the size of the 
triangle nor the degree (within limits) of the angle A. It 
is to be noted that this is not an accounting of anything 
actual but an abstract condition to which any actual 
triangle must answer. In other words, it is the special 
constitution of a triangle by which it can be operated in 
a certain way. 

The definition of scientific objects as functions must be 
noted to include the various names given to scientific 
objects: entities, concepts, processes, events, laws. Now, 
an entity or a thing is defined by its function, as we saw 
above. A match, a street car, copper sulphate, velocity, 
all these are defined by their function, i.e. by the way 
they can act. And we have seen that this is the determining 



NATURE OF FIELD OF SCIENTIFIC INVESTIGATION 113 

fact in their constitution. Thus we always mean by an 
entity (in science or out) a function. 

It may not be so clear that a concept is a function, but 
such is the case. A concept is the mental recognition of a 
function which is not mental. Thus the concept, table, 
refers not to a particular table but to any table, i.e. to the 
function, table. Similarly, democracy refers to a possible 
condition or function and not to anything actual. The 
mental image by which the mind grasps ideas or functions 
is not itself the concept. Thus the word, beefsteak, may 
bring up in many minds different images, visual, auditory, 
olfactory, or gustatory or many of these; but that to 
which the image refers, i.e. the concept, beefsteak, is the 
same. When a concept is spoken of in science, it is 
obviously not the mental aspect of it which is meant, 
but rather that to which the mental refers. And this is 
identical with the scientific entity. 

That a process is also a function becomes evident from 
an examination of process. A process is a course of events 
which is separable from the sum-total of happenings. It 
Is only separable on the basis of its special manner of 
procedure. Thus what defines any certain process is not 
events so much as the certain form they take. But this 
form is a function in operation. The 'processing' of wood 
pulp into rayon is obviously a function, since it is defined 
primarily by the end in view, and secondarily by the 
particular events which are means to that end. In other 
words, processes are defined by the end toward which 
they are directed. And this determines the events which 
lead up to that end. The process of electrolysis is like- 
wise a function, inasmuch as it is defined by the breaking 



H4 WHAT SCIENCE REALLY MEANS 

down of water into oxygen and hydrogen, and second- 
arily, by the electro-chemical events which bring this 
about. 

It is apparent, however, that when a process is referred 
to, reference is not made to any particular actual process 
but rather to certain possibility of actual process, so that 
the process is not confined to place or date. In this light 
it will be seen that a process is a function. It is also to be 
noted that there is no logical distinction between a pro- 
cess and an entity; one is merely viewing a function as a 
possibility of action (entity), and the other is viewing a 
function as in action (process). 'Entity' is function as 
potential; 'process' is function as kinetic. The distinction 
between these can be more clearly understood when we 
note that processes arc constantly spoken of as entities. 
The term, hypostatization, or reification, means the 
viewing of a process as an entity. But this is no figure 
of speech, since whenever we talk of an entity we also 
mean a process, and v ice versa. For instance, a mouse 
and a mountain are entities; but they are equally pro- 
cesses, since that which makes their functions what they 
are is in a constant state of change and motion. Mice 
grow and die; mountains constantly erode. And the parts 
which make up these entities are always in flux: cells, 
molecules, atoms, etc. All actual things are in process, 
and it is the process itself which shows enough uni- 
formity to be isolated and spoken of as persistent. 
When this is done, we have hypostatized the process 
into an entity. 

Obviously, an event is a function since it answers to 
the same definition as a process. No event can be called 



NATURE OF FIELD OF SCIENTIFIC INVESTIGATION 115 

an event without defining its purpose or end or direction. 
Thus whatever we have said about process applies 
equally to event. 

Of our group of scientific objects, it remains now only 
to show that a law is a function. A law is a necessary 
uniformity to which relevant processes and events must 
conform. It may therefore be called a general function 
which conditions particular functions, just as Ohm's Law 
is a general function conditioning the particular function 

V 
of a given electrical current in a given wire. = R, 

where V is the potential (volts), and I the current 
(amperes) and R the resistance (ohms). A law, then, is 
the notation for a general function which governs par- 
ticular functions inexorably, and is therefore a statement 
of fact, which is just as objective as a mouse or a 
mountain or electrolysis or entropy. It is observable in 
the same way, namely, in and through experience, and 
it is conceivable in the same way, namely by means of 
words, symbols, or images. It is equally with them not 
actual, being the governing function for actuality, i.e. it 
can be actualized or even exemplified in actuality. Thus 
a law can be called a scientific object: an entity, a con- 
cept, a process or a series of events. 

We have seen that the best and most embracing term 
to cover all of these terms is that of function, which 
may be taken to mean what it means in ordinary dis- 
course: possibility of certain action or a special constitu- 
tion by which it enjoys a certain possibility of action; 
or which may be taken to mean what it means in mathe- 
matics : an invariant relation between variables. Thus the 



n6 WHAT SCIENCE REALLY MEANS 

scientific objects the subject matter of science consist 
in a world of real relations, expressible by functions. 5 

FUNCTIONS IN THE VARIOUS SCIENCES 

Let us take examples from each of the various sciences 
in order to show that their subject-matter is always that 
of abstract relations or functions and never that of any- 
thing actual. This is obvious in the more abstractive 
sciences, but perhaps it should be illustrated. 

In analytic geometry, x* + y 2 = r 2 (for rectangular 
co-ordinates, x and y) is the equation of the circle. But 
obviously this equation does not represent any given 
circle or any actual circle, but rather the conditions which 
any actual circle must satisfy. 

In physics 'density' is the mass per unit volume of a 
substance, i.e. it is the relation between mass, expressed 
in units, and volume, expressed in units, and is not to 
be understood as an actual 'quality' of any actual thing 
in the sense of being actually separable from it. 

In astronomy, 'planet' does not refer to a certain 
actual body of matter in all its sensible effects. It refers 
to the function of any body, except a comet or meteor- 
oid, that revolves about the sun. The actual bodies 
named Venus, Mars, Saturn, etc., perform this function; 
and in so far as they do they are planets. Should these 
bodies, from some cause or other, cease to so revolve, 
they might continue to be actual bodies but they would 

5 Since mathematical symbols are the most abstract (i.e. non-actual) 
expressions which can be found to represent relations, it follows that 
mathematical formulations of functions become the true goal of all 
science. 



NATURE OF FIELD OF SCIENTIFIC INVESTIGATION 117 

certainly not be planets. The term planet refers to the 
function and not to the actualization of it. Similarly, if 
new bodies are discovered to revolve about the sun, they 
would be rightly termed planets in so far as they fulfil 
this function. 

In chemistry, Valence' is defined as the ability of an 
element to combine with another element. This does 
not refer to any given actual quality of an element, in 
the sense of a property which can be actually separated. 
It is a function of the combination or relation between 
elements. It is true that it could be determined by the 
number of free electrons on the outer layer, but this does 
not affect the logical fact that valence is to be defined 
only in terms of relations between elements. 

In zoology, 'marsupial' is defined as a mammal having 
a pouch in which the young are carried. Plainly this does 
not describe any actual opossum or kangaroo except in 
so far as they exemplify this function. A female kangaroo 
born without a pouch would be a kangaroo but not a 
marsupial. 

In botany, 'chloroplast' is defined as a plastid containing 
chlorophyll, developed only in cells exposed to the light. 
Obviously we have in chloroplast a function between 
certain plastids and light, which is only exemplified in 
actuality when this function is satisfied. Thus it cannot 
properly be identified with any actual plant which may 
or may not exhibit it. 

In economics, 'economic man' is defined as that man 
whose activities are entirely concerned with the economic 
level. Certainly no such actual man exists, since although 
every man is sometimes and somewhat concerned with 



n8 WHAT SCIENCE REALLY MEANS 

economic activity, no man is altogether so concerned. But 
the fact that the economic man is non-actual does not 
make the abstraction, the 'economic man/ an unreality. 
Its reality lies in its functional nature which actual men 
may or may not share in more or less degree. Thus once 
again 'economic man' refers to abstract relation or 
function. Similarly the 'bourgeois class* does not refer 
to any actual member of this economic class who may 
at the same time be or become in other ways members 
of the proletarian or capitalist class. It therefore refers to 
a certain function in society, which varying members 
to some extent fulfil at different times. 

In sociology, 'criminality* is defined in terms of the 
breaking of certain established laws of society. Thus it is 
not properly applicable as a fixed attribute of any actual 
person. There is no criminal type per se but only persons 
who participate more or less in such anti-social behaviour, 
i.e. in the particular social (or rather anti-social) function. 

In politics, 'parliamentarianism' is defined as that form 
of government in which the State confers upon the 
legislature (elected by popular vote) the complete control 
of the administration of law. Probably no actual State 
has ever been entirely governed in this way, yet parlia- 
mentarianism applies to some states in so far as they 
partially fulfil this function. 

We have seen that the subject-matter of every science 
is a set of functions which are strictly non-actual, being 
exemplified more or less in actuality, but never identifi- 
able altogether with it. They arc the forms or relations 
which actuality must follow and by which actuality is 
understandable. When these functions or abstractions are 



NATURE OF FIELD OF SCIENTIFIC INVESTIGATION 119 

known, they are properly called concepts; but they are 
not created by the mind nor do they depend upon it 
for their functions to be fulfilled, in the sense of having 
no existence when not cognized. The subject-matter of 
science is therefore strictly abstract and non-picturable, 
and whenever pictured is a convenience which finally gets 
in the way by being misleading. Thus the symbols of 
mathematics are the best scientific representation. 

ARE SCIENTIFIC OBJECTS EMPIRICAL? 

From the above exposition of the nature of scientific 
objects, we can perhaps see why the mentalistic and the 
operational interpretations arose and how they went 
astray. The mentalists correctly comprehended the fact 
that scientific objects are not to be strictly identified 
with actuals, and that scientific functions are most easily 
manipulated in their mathematical formulations. They 
understood very well that the world picture of science 
could be put without distortion only into mathematical 
terms. But once having decided that scientific objects are 
not actual, this school declared them mental, presumably 
because they are conceivable by the mind. 

On the other hand, the operationalists, striving to save 
the reality of scientific objects, tried to hold on to 
actuality. They went half-way in the understanding of 
the fact that scientific objects are functions, i.e. that 
scientific functions are actually operable. But the existence 
of functions as such when not in process or operation 
was denied. Thus scientific functions when not in 
dynamic relation, were supposed to be only summaries of 
real dynamic relations, and thus concepts in the mind. 



120 WHAT SCIENCE REALLY MEANS 

We may conclude by pointing out that both mentalists 
and operationalists are partly right and mostly wrong in 
their understanding of the nature of scientific objects. 
They are non-actual, they are operated in actuality, they 
are conceivable; but they are also real, abstract, and 
non-mental. 

Where, then, has our inquiry into the nature of 
scientific objects led in regard to the main thesis of this 
work: the nature of empiricism ? In other words, what 
is the relation between empiricism and the objects of 
science as defined, namely, as functions? On the one 
hand, can we assert that the actual objects of ordinary 
observation are not empirical? Certainly we cannot. 
Apples, horses, dances, and storms are empirical; they 
are also actual. But on the other hand, can we throw 
out of the category of the empirical those abstract 
scientific entities which we have been discussing, such 
as valence, density, radio-active disintegration, etc. ? 
Obviously to do so would be to destroy the claim of 
every science to be empirical. This is tantamount to 
destroying the idea of science itself. Assuredly empiricism 
has some close connection with actuality but is not to 
be understood as being identical with it. 

Ultimately empiricism docs rest upon the observation 
of actuality. But the understanding of observation as the 
mere run of experience tells us nothing. At the lowest 
level of observation, patterns are discovered within 
actuality which are not strictly sensory. For example, 
that a chair or a table has the function that it does is 
not revealed by sensory analysis or observation unin- 
tegrated. Thus observation is shot through with inferences 



NATURE OF FIELD OF SCIENTIFIC INVESTIGATION 121 

of function, which finally become so familiarly accepted 
that functions are thought to be,, sensed. For instance, the 
average city dweller 'sees' the black instrument on his 
table as a telephone, but to one ignorant of the use and 
purpose of the telephone it would only be a black object 
of a certain shape to which he could assign no meaning. 
But that the function of an ordinary object is not sensory 
per se surely does not mean that it is not empirical, since 
its function is demonstrable in experience. If this is the 
case, the term, empirical, can and must be applied to any 
function which is either observable in operation or which 
can be inferred by observable processes in nature. 

Empirical entities do not stop here, since the inferences 
from agreed on hypotheses may be verified by reference 
to the body of agreement. Thus that which was not 
empirical can become empirical, e.g. molecules which 
were once only hypothetical, are now empirical. They 
are empirical even though they are not yet visible through 
the microscope. The empirical field is not a fixed affair 
but is made comprehensive according to the body of 
agreement. The law of action and reaction always 
existed and always will, but became through scientific 
recognition an empirical fact. In other words, we have 
discovered that empiricism is not a quality of the ob- 
jective world but a function of scientific inquiry. 

In this chapter we have examined the nature of 
scientific objects. In the next chapter we shall make an 
analysis of scientific method or the method of empiricism 
in science. 



C H AFTER VI 
THE METHOD OF EMPIRICISM 

/ hope I shall not shock the experimental physicists 
too much if I add that it is also a good rule not to 
put over-much confidence in the observational 
results that are put forward until they have been 
confirmed by theory. 

A. S. EDDINGTON 
THE BRUTE FAITH IN THE GIVEN 

WE have arrived at the conclusion that the entities of 
science are not per se either empirical or non-empirical. 
Empiricism concerns the status of scientific knowledge. 
We must now make an analysis of the empirical method 
as employed in science, and in order to accomplish this 
task we must examine empiricism at the level where it is 
not exclusively scientific, even below the common-sense 
level, at the barest giveness of sense experience. 

There is an element in all experience which is insus- 
ceptible of further analysis. This element cannot be 
rationalized any further than to state that it is for sense 
experience. Such brute facts are those which thrust 
themselves upon us without any explanation. Nothing so 
sophisticated as a lump of sugar or a book or a carnation 
is meant. We mean the sight of redness, the smell of 
honeysuckle, the touch of a stone, the sound of a bell, 
the taste of salt. For all these cases, the sources which 
convey the sensations must be dropped. The bruteness 
concerns the sensation itself, and not any judgment about 
its source or cause, or even position of occurrence in 



THE METHOD OF EMPIRICISM 123 

time and space. It must also be noted that the existence 
of these brute facts cannot be proved or explained in 
any final way. In other words, these presentations are 
accepted on faith, agreed upon roughly by convention, 
and regarded as merely 'given/ As such they are the 
irreducible building blocks on which all experience is 
mounted, and therefore the basis on which science and 
even logic ultimately rest. On the identity of these 
presentations and their differences, all rationality relies. 
Such facts constitute the final court of appeal for both 
logic and empiricism. Nevertheless, the rational structure 
has to do with differences and relations between such 
things which in themselves tell us nothing about their 
intrinsicness. 

The pure bruteness of experience, as we have set it forth, 
has never been entertained by anyone. There is no con- 
tent without form in anything experienced; no sensation 
has ever taken place without some kind of minimal 
judgment. We cannot see red without the idea of redness 
or the understanding of something red. A sound or an 
odour is at least given spatial location, however vague, 
simultaneous with the sensation itself. These brute facts, 
together with judgments about them, constitute indi- 
vidual experience and the world of social agreement. 
Inasmuch as there is no purely brute experience, per- 
ception is made possible by an understanding of the 
relations between brute facts. Thus the cubeness of a 
cube is not a fact which can be experienced as such, 
since what is seen or felt is always a surface. A cube is, 
then, an inference from the relations of sensations of 
brute facts. But certainly a cube is part of the social 



124 WHAT SCIENCE REALLY MEANS 

world, and as such, an empirical fact. The sciences largely 
concern this social world. However, this statement must 
be modified in two important respects. The science of 
psychology, for example, may take as its field of study 
the private order of experience dreams, phantasms, and 
images. And all the developed physical sciences, though 
they start with the world of social agreement, suppose 
the existence of a natural world of which social agreement 
covers only a small part. 

We have seen that brute facts underlie empiricism, but 
that no empirical facts, even at the common-sense level, 
are purely sensory. We might also infer from the above 
that the data which constitute empirical subject-matter 
for one science would not be empirical for another. For 
instance, the pink rats seen in delirium tremens are not 
empirical from the point of view of zoology. But the 
same bit of evidence is accepted as empirical by abnormal 
psychology. So far it would appear that the test of 
empirical subject-matter is a function of agreement 
among those qualified to judge. But this is not enough. 
Social agreement is still undercut by the brute facts of 
sense experience, which are 'agreed' upon, without 
choice and of necessity. Science does often contradict the 
judgments of common sense which rest upon experience, 
but it cannot ultimately contradict the senses themselves. 
The abstractions of science leave sense experience so far 
behind that they do not seem ever to have started from 
it. Nevertheless, the structure has been built ad seriatim 
from brute facts upward, and must be demonstrably 
non-contradictory to them. Science, therefore, does start 
from sense experience. 



THE METHOD OF EMPIRICISM 125 

ABSTRACT CHARACTER OF COMMON EXPERIENCE 

It is not ordinarily recognized how much beside sense 
experience enters into the world of common agreement. 
We have only to mention such non-sensory facts as 
time, space, causality, and chance, to show that without 
such categories sense experience does not make 'sense/ 
It need hardly be urged that we do not directly experience 
time, space, causality, or chance. These are constructions 
of brute facts, yet they are facts just as hard and fast as 
the evidences of sense experience themselves. And unless 
one assumes the philosophy of radical empiricism, they 
are accepted as such. 

This necessity of categorization, with its universal and 
implicit acceptance, is well illustrated by the existence 
of what is called history. History understood as a succes- 
sion of actual events which have happened is nothing 
anyone would consider to be history. Particular events 
must be shown to have some kind of direction or meaning 
before history is admitted. The direction and meaning of 
events arc notoriously judgments. But even if we admit 
that the mere succession of actual events is history, such 
a chronicle akeady presupposes a fixed time-order, which 
is surely never sensed. And as we have shown, even the 
observation of these events as they occur cannot be made 
without non-sensory inference. The movements of 
horses and men is already an inference from brute 
sensations. But the movements of horses and men can 
only be called a 'battle* by inference. However, no 
history stops with even such judgments, but goes on to 
infer results and causes and .to link these up with such 



126 WHAT SCIENCE REALLY MEANS 

abstract facts as 'revolution/ 'increasing nationalization/ 
the 'decline of the West/ etc. Despite the fact that 
historians will largely disagree on the speculative truth 
of such broad movements, speculation is always de- 
manded, and all historians are in agreement concerning 
what they call the 'facts/ i.e. rudimentary constructions 
(less daring inferences). 

From recorded history of the more remote past, we 
may turn to the daily affairs of common experience. 
Here we can see also that abstractions play the part of 
accepted fact in the understanding of brute experience. 
For instance, no one doubts that there is a political 
'sphere* or an economic 'scene/ Indeed, most of our 
discussions about 'what is going on in the world' take 
place in terms of non-sensory abstractions. Will the 
United States Government become more or less cen- 
tralized ? Will the stock market recover ? Is agriculture 
to become industrialized? Is communism in Russia 
moving to the right ? Every one of these questions is 
framed almost altogether in abstract terms, terms many 
times removed from the sensory. Yet they have the 
validity and reality of stubborn hard fact. No one doubts, 
for instance, that agriculture is a real thing though no one 
can sense agriculture. The operations of the stock market 
are to many persons the most real of all realities; yet who 
has ever sensed a stock market operation ? The best that 
can be seen are brokers walking to and fro and writing on 
slips of paper, or ticker tape, or chalk marks; but certainly 
these are not equivalent to the fact of the stock market. 
We have seen that the empirical world we live in is 
shot through with, and indeed mostly composed of, 



THE METHOD OF EMPIRICISM 127 

non-sensory and abstractive facts. To understand this 
world to some extent is the test of sanity. The insane 
man is not the man who lacks his five senses (indeed, 
many sane persons lack one or more senses, e.g. no one 
would call Helen Keller insane). What the insane man 
lacks is the ability to make abstractions from his sense 
experience in a way which agrees with the abstractions 
of his fellows. Hence it is upon the quality of abstractions 
and not upon the quality of sense experience that sanity 
depends. The insane are said to live in an unreal world, 
e.g. they cannot understand social realities, and social 
realities are abstractions. Nobody acts as though he truly 
doubted that social facts are real and that abstractions are 
empirical. 

Having seen how the actuality of common experience 
is compounded of abstractions far in excess of the 
sensory, let us now turn to science to see how the process 
of abstraction is carried further. Just as common experi- 
ence infers from pure sensation, science starts from the 
facts of common experience and makes inferences from 
these to arrive at its peculiar abstractions. True science 
does not start until abstractions are made from actuality. 
Science begins by abstracting from actuality, past and 
present, and thus from place and date. It therefore follows 
that science does not deal with unique particulars; 
indeed, it gets away from sense experience altogether, 
even though the terms which it uses to express its mean- 
ing have perforce a certain sensible aspect. These ab- 
stractions from actuality are the first empirical entities of 
science, non-sensory. Thereafter science deals with these 
abstractions as though they were given, and no further 



128 WHAT SCIENCE REALLY MEANS 

with the sensory facts on which they ultimately rest. 
Indeed, for purposes of procedure, these abstractions are 
the 'given' of science. 

PROCEDURE OF SCIENTIFIC ABSTRACTION 

The subject-matter of science is removed from actuality, 
to which it returns only to make sure that its entities 
are still empirical, i.e. that they check with sensory fact. 
We have seen in the last chapter that the subject-matter 
of all the sciences is functions. We have seen in the last 
section how these functions are arrived at by abstracting 
from actuality. Thus the realm of science is the real but 
non-actual realm of functions, and each science deals 
with a set of functions abstracted by means of some 
canon or level of analysis. For instance, physics deals 
with the space-time functions of actuality abstracted 
from actuality, and biology deals with organizational 
functions of the living physical organism abstracted from 
those actual living organisms, etc. In this realm of 
functions the categories of actuality have no application. 
Functions do not change, since they are the unchanging 
expressions of change between actuals. Thus functions 
are timeless. Again, the category of space has no applica- 
tion to functions, since the relation between things in 
space has no location. Functions have no affective value; 
not only are they non-picturable and non-sensory, but 
neither do they have the value connotations of good, 
bad, ugly or beautiful, worthy or unworthy. Science for 
the purposes of science is wertfreiheit. 1 

1 This term, coined by Max Weber, is translated by Brock as the 
"necessity of abstaining from valuations in science." See Werner 
Brock, An Introduction to Contemporary German Philosophy, p. 27. 



THE METHOD OF EMPIRICISM 129 

When science reaches its abstractions from actuality, it 
does not stop with them, nor does it simply accumulate 
a set of these abstractions, largely unrelated. It rather 
endeavours to build a system of such functions by (a) find- 
ing through analysis the implication of those functions, 
and (b) abstracting from those functions and arriving by 
induction at functions of greater generality which include 
the lesser as special cases but do not replace them. 

An example of (a), the finding through analysis of the 
implications of functions, may be taken from the fact that 
Priestley's discovery of oxygen is a specific implication 
of the more general function of chemical element. 
Specificity in the finding of less general subsidiary func- 
tions is as essential for scientific knowledge as is the dis- 
covery of the more general. But specificity in this sense 
is not to be confused, as it so often is, with unique 
individuality. 'Oxygen/ as a scientific entity, is no more 
actual than is 'chemical element/ but it is more specific. 
Both have to deal with possibilities. 

An example of (6), the process of abstracting from 
abstractions, may be taken from medical science. The 
first abstraction in regard to immunity was made from 
actual cases of special diseases, e.g. immunity from 
diphtheria, from smallpox, and then abstracted as the 
principle of immunization, regardles of any particular 
disease. Another example of the process of abstracting 
from abstractions may be taken from the differential 
calculus. Rate of change is certainly an abstraction; but 
we can abstract from it to the second rate of change (the 
rate of acceleration). This second derivative is the rate of 
a rate, and thus a further level of abstraction. 



130 WHAT SCIENCE REALLY MEANS 

As the empirical test of the first abstractions of science 
is actuality or demonstration, just so the empirical test of 
the higher abstractions arrived at by induction are the 
first scientific abstractions akeady tested. It is true that 
in most cases the second level of abstractions can be 
tested directly against actuality, i.e. experimentally. But 
this is not the prime test. The prime test is against the 
first level of abstraction. Nor does science necessarily stop 
here, but can go on indefinitely; and in each case the 
empirical test can be either against the last level of 
abstraction or against any level or against actuality itself. 

A system erected in this way ultimately rests, as it 
must, on brute sensory fact. But the dependence is neither 
apparent in the higher levels nor necessarily remembered 
in the empirical check. The roof of a house does not 
seem to rest on the ground; nor does a builder fashion a 
roof with this thought in his mind, but rather to conform 
to the structure of die whole. Nevertheless, the roof rests 
on the joists, the joists on the uprights, the uprights on 
the foundation, and the foundation on the ground. The 
roof must, of course, rest finally on the ground, but it 
must also form with the rest of the house a self-consistent 
structure. 

It is sometimes supposed that non-Euclidean geometry 
has no necessary connection with experience but is a 
purely formal science. Non-Euclidean geometry has its 
origin in the denial of the parallel postulate and the ac- 
ceptance of certain others. But, of course, Euclidean 
geometry is an abstraction from the observed motions of 
rigid bodies, and therefore plainly empirical. Since non- 
Euclidean geometry is only once removed from the 



THE METHOD OF EMPIRICISM 131 

empirical basis, it too is empirical in the same sense that 
all the abstractions of so-called applied mathematics are 
empirical. If Tom stands on John's shoulders and John 
stands on the ground, can it be said that because Tom 
no longer has any direct contact with the ground that 
he is independent of it ? All sciences are empirical inasmuch 
as they directly or indirectly depend upon sensory fact, 
and all sciences are empirical in so far as they form self- 
consistent systems. 

THE PRINCIPLE OF ECONOMY 

However necessary the connection between empiricism 
and the sensory, more is needed for the empirical proof 
in science than demonstration by observed fact. Contra- 
dictory theories can be shown to agree with observation. 
A notorious case is the Ptolemaic and the Copernican 
systems which take into consideration sensory fact, on 
the basis of which they would still be valid. Nevertheless, 
the Ptolemaic system is no longer held to be an empirical 
fact of science, since it no longer agrees with the other 
inferences built up in modern astrophysics, with its 
telescopic and spectroscopic inferences. It must be noted 
that these newer theories are also based on observances 
and thus we have two theories in agreement with 
sensory fact yet mutually contradictory. The preference 
for the Copernican does not depend at all upon sensa- 
tions, but upon its ability to embrace and form one 
system with new inferences and old laws. 

Thus the first and main empirical test in science is that 
of self-consistency within the given system, i.e. the body 
of accepted theory. If a new theory meets this test, it then 



132 WHAT SCIENCE REALLY MEANS 

rests directly upon older and accepted theories, and so 
ad seriatim, until it rests upon theories which fit the 
observed facts. Thus the consistency of a theory with a 
given system means ipso Jacto that it is dependent upon 
sensory fact. But something more is involved. One part 
of empiricism is the principle of economy, the admonition 
that no more explanation than is absolutely required be 
introduced. This is a variant of Occam's Razor, which 
states that entities must not be multiplied beyond neces- 
sity. Thus one theory which covers two separate groups 
of fact and theory is always preferable to two theories. 
And a theory which is addressed only to an isolated 
group of facts and has no relation to other theories is 
immediately suspect and never altogether accepted as 
empirical. This is what the scientists denounce and reject 
as ad hoc theory. 

Einstein's general theory of relativity, so completely 
endorsed that it is already the empirical basis for further 
investigation, was largely accepted by physicists because 
it was able to embrace and agree with both the Newtonian 
theory of gravitation and inertia, and the new facts dis- 
covered since Newton, e.g. the failure to detect the ether 
drift. 2 The theory of relativity has supposedly been 
proved by three experimental tests: (i) the precession of 

2 Lorenz and Fitzgerald explained the null result of the Michelson- 
Morley experiment by supposing that motion through the ether 
altered the linear dimensions of bodies in a way which could be ex- 
pressed mathematically. Here was an ad hoc theory which was sup- 
planted by relativity, and the alleged 'conspiracy' to prevent the 
measurement of absolute motion was reformulated as a uniformity of 
nature in the principle of relativity, in a way to make absolute motion 
supererogatory. 



THE METHOD OF EMPIRICISM 133 

the perihelion of Mercury, (2) eclipse photographs, and 
(3) the shift toward the red end of the spectrum in the 
companion of Sirius. All these experiments bore out 
Einstein's law to closer approximations than Newton's. 
However, the theory of relativity does not rest on these 
experiments but was proved before them, and has only 
been confirmed by them. The theory of relativity 
eventually is acceptable because of its consistency with the 
prevailing body of physical theory. For obviously many 
theories might be constructed to explain the results of 
these three experiments. But unless they agreed with 
the main body of physical theory, no physicist would 
give them an instant's consideration. 

We have been exhibiting empiricism as the principle of 
economy. As such it is a cautionary measure and not 
strictly a method, not the leading principle of science, 
since by itself it does not constitute science, forming 
nothing new but holding down the new to conformity 
with the old and accepted. Without it, scientific specula- 
tion would be too wild and unintegrated. Thus it is a 
warning that too many steps in the development of 
science cannot be skipped. This is not a matter of time 
since development can be slow or rapid; but it must 
always integrate itself with what has gone before. With 
this principle in mind, science is justified in holding in 
abeyance, or in throwing out, all theories which, though 
they check with sensory fact, make no connection with 
the given stage of knowledge. We are reminded of 
the anecdote of the Pope who rebuked Galileo by saying 
that the earth could move around the sun or the sun 
around the earth. Here was an anticipation of relativity 



134 WHAT SCIENCE REALLY MEANS 

which could have no scientific standing since it was 
highly disconnected from the stage of scientific inquiry 
of that day. Again, the alchemists' theory of the transmu- 
tation of the elements has been shown to be possible; 
nevertheless, alchemy has no scientific standing, since it 
failed to show how the transmutation was to take place. 
The occult sciences of our day astrology, theosophy, 
and spiritualism may entertain theories which are true, 
and certainly they have unearthed facts for which some 
accounting will have to be made, but they are rejected 
by the body of science to-day for the simple reason that 
so far they have not been confirmed by scientific theory, 
i.e. no explanation in terms of accepted scientific facts 
has as yet been given. Thus in spite of their sensory data, 
which is empirical, these sciences are not empirical. All 
this is another way of saying that sensory facts by them- 
selves are not enough for scientific empiricism but must 
be supported by theory which economically embraces 
all of them and shows them consistent with older 
accepted theories. 

RELATIVITY OF EMPIRICISM 

Empiricism is a relative term. It is relative to the pre- 
vailing acceptance of what is real. This broad statement 
must not be read to mean that what can be considered 
empirical is an arbitrary affair. It is, on the contrary, a 
fixed affair, as we have shown, always inevitably de- 
pendent upon the stage of knowledge at any time. But 
no more is it a matter of the subjective will. Neither the 
impulse nor the reasoning of the individual can make 
empirical what is not empirical, nor make what is non- 



THE METHOD OF EMPIRICISM 135 

empirical empirical. To explain what is meant by 
saying that empiricism is a relative term, we may give 
three examples of its relativity. 

First, what is empirical for one science is not necessarily 
empirical for another. The atom of physics is an empirical 
entity for physics. The atom of chemistry is an em- 
pirical entity for chemistry. But the atom of chemistry, 
with its many combining qualities, is not empirical to 
the science of physics, the only empirical property for 
the latter science being its mass. In biochemistry the 
biological functions of growth, self-repair, and repro- 
duction are not empirical; whereas in botany and 
animal biology these qualities are the most empirical. 
For the etiology of disease, capitalism is not an em- 
pirical fact, whereas for political economy it most 
certainly is. In other words, for any special science the 
empirical can only apply to what is relevant. And the 
relativity of empiricism is seen to mean the relevance. It 
does not necessarily follow, however, that all these 
examples are reversible. On the contrary, as we shall 
show, 3 the series of relevance is non-reversible. 

Secondly, what is empirical for any science is not 
necessarily empirical for common sense. This should be 
obvious. The symbiosis of biology, the dipole orientation 
of electromagnetics, the spinors of mathematical physics, 
the joint cost of economics, the pyritohedrals of crystallo- 
graphy, are none of them observable to common sense, 
that is to say, they are not empirical to common sense, 
but require special knowledge to be observed. 

Thirdly, what was once non-empirical can become 
8 Cf. p. 148. 



136 WHAT SCIENCE REALLY MEANS 

empirical and vice versa. The former assertion will be 
readily acceptable. We have only to mention electrons, 
protons, quanta, vitamins, planets, etc. The latter asser- 
tion is not so readily acceptable, but true nevertheless. 
Phlogiston, caloric, epicycles, the bodily humours, these 
were once empirical entities, empirical by every test that 
science could devise. They were manifest in sense ex- 
perience and they agreed with the existing body of 
knowledge. But these entities which were empirical are 
no longer empirical because they no longer answer the 
second requisite, i.e. they no longer agree with the 
accepted systems of knowledge, or at best they are not 
necessary and therefore they are thrown out on econo- 
mical grounds. For instance, forces are not required to 
explain anything; they are therefore dropped. Entities 
which are found to have no necessity are destroyed rather 
than allowed to multiply, in the interest of empiricism. 
Three kinds of entities appear in science, the empirical : 
the heuristic, and the mythologic. An empirical entity is 
any entity whether actual or non-actual which has been 
tested against actuality and found to be allowed. An 
heuristic entity is one which is set up but which has 
neither been accepted nor rejected. A mythologic entity 
is a purposive entity employed as efficiently causative. 4 
It is clear from the foregoing that empiricism is a con- 
stant function which has to do with self-consistency 
within a given system, granted the understanding that 
any such system indirectly and finally rests on unde- 
niable brute facts. Into and out of this constant function, 

4 No derogation of the reality of purposive entities is intended, but 
only of their illicit use in science. 



THE METHOD OF EMPIRICISM 137 

items pass, so that while the empirical colours are fading 
on some entities, others are being freshly painted with 
them. But the fact that entities once deemed empirical 
are no longer so considered means only that such entities 
have been redefined and given new terms; and that new 
entities constantly enter the empirical field means simply 
that knowledge of the world is increasing with the pro- 
gress of science. Too much has been said about the 
'fictions of science.' In truth there are no fictions in 
science in so far as there is science. The fictional aspect 
of scientific entities, such as forces, phlogiston, etc., is 
the illegitimate attribution of actuality to the name of a 
function. When the names of these functions are changed, 
the fiction of the old disappears, but the truth about the 
function remains. Scientifically, the 'fiction' never was a 
fiction. 

There are, then, no limits to what may become em- 
pirical. What may become empirical is limited only by 
its ability to continue to have relations with existing 
knowledge in an orderly, economic, and necessary 
manner. In short, there are no limits to what can become 
empirical, but there are absolute limits to empiricism. It 
must be noted that the degree of abstractness of an 
entity has nothing whatever to do with whether it is 
empirical or not. 

ALL SCIENCES EXPERIMENTAL 

Every science has its empirical aspect. There are no non- 
empirical sciences. But the experimental field of each 
science is different, depending upon the portion of the 
totality of existence selected for study. Every science, in 



138 WHAT SCIENCE REALLY MEANS 

other words, abstracts from a portion of actuality and 
omits everything else as irrelevant. The portion of 
actuality abstracted by physics is not that abstracted 
by sociology, and vice versa. Thus the sciences can be 
arranged in a hierarchy, according to the level of actuality 
from which they take their start. This is the hierarchy 
of the sciences arranged according to their organization 
of actuality. 

Taking our start from physics as the lowest known 
science in the organization series, we can readily see 
that the biological is an organization of the physical, and 
that the sociological is an organization of the biological, 
and that each of these sciences has, appropriate for study, 
functions of organization not included in lower sciences. 
But the abstractiveness of each science is independent 
of the hierarchy of organization. Each proceeds from 
brute facts through partly logical actuality to logical 
abstractions and then on to still more abstractive levels, 
and finally to still higher abstractive levels where mathe- 
matical formulation is possible. It is, of course, true that 
at earlier stages of abstraction, mathematical formulation 
is possible; but if a science becomes mathematical before 
it is sufficiently abstractive (i.e. before it is sufficiently 
logical) its mathematical formulations will have little 
validity. 

No matter how abstractive a science becomes, it is not 
carried to the next organizational level. The abstractive 
level goes out, not up ; and the organizational level goes 
up, not out. Quantum mechanics does not help in the 
understanding of heredity, any more than did Newtonian 
mechanics. The appropriate field for experimental 



THE METHOD OF EMPIRICISM 139 



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DIAGRAM I 

THE FIELD OF THE SCIENCES 

The diagram is not intended to be an exhaustive list of the sciences. 
We have given the main divisions which, broadly speaking, may be 
taken as including the others. For instance, physics includes mechanics, 
thermodynamics, chemistry, crystallography, astronomy, physiology, 
medical science, etc.; sociology includes economics, anthropology, 
politics, philology, criminology, etc., and each in turn may have its 
subdivisions, ad seriatim. We have included, however, at separate 
levels the infra-physical, if there be any science dealing with organiza- 
tion at a lower level than the physical, and ultra-sociological, when 
that science is discovered. 



HO WHAT SCIENCE REALLY MEANS 

demonstration is the total ground covered between brute 
facts and the point arrived at in abstraction. The em- 
pirical proof works back to the less abstract, and not up 
in the organizational series. We cannot demonstrate the 
validity of bimetallism by reference to the atomic table 
of the elements. We cannot disprove the teleology of 
living organisms by reference to biochemistry. We 
cannot demonstrate free will at the sociological level by 
reference to indeterminacy at the sub-atomic level. 

When we state that the appropriate field for experi- 
mental demonstration is the total ground covered between 
brute facts and the point arrived at in abstraction, we 
mean exactly what was stated above, 5 where it was said 
that the first empirical test in science is that of self- 
consistency within the given system, that self-consistency 
within the given system is ipso facto dependent upon 
sensory (i.e. brute facts) but involves something more. 
In the empirical proof it is always possible to return to 
the level of sensory brute facts, but it is seldom necessary. 
Empirical proof usually consists of going backward one 
step to the immediately preceding stage of abstraction. 
The new and more abstract generalization is empirically 
proved when the immediately preceding abstract general- 
izations are shown to be more special instances of the 
one under consideration. This holds for every branch of 
science; and to the extent to which every study generalizes 
in this way it is equally empirical. 

5 See this chapter, section on "The Principle of Economy.'* 



THE METHOD OF EMPIRICISM 141 

THE EXPERIMENTAL SCIENCES OF LOGIC, MATHEMATICS, 
METAPHYSICS 

The classical sciences, e.g. physics, biology, etc., are 
recognized to be empirical sciences. But logic, mathe- 
matics, and metaphysics are not so recognized, chiefly 
perhaps because they do not fit into the hierarchy of 
sciences arranged according to levels of actuality. As 
our diagram suggests, logic and mathematics can be 
abstracted from any and all sciences or from brute facts 
directly, whereas metaphysics is the widest generalization 
from all knowledge, including logic and mathematics as 
well as brute facts and the sciences. But, as we have 
shown, the empirical status of science has nothing to do 
with the organizational series. The series only delimits 
what are the empirical fields for those sciences. We shall 
show that logic, mathematics, and metaphysics them- 
selves can be and indeed must be empirical. 

Logic is an empirical science. When abstracted and 
presented as an independent system, logic is inde- 
pendent of actuality. But it rests on the most empirical 
facts in experience, namely, the distinctions and dif- 
ferences between brute facts, without which there would 
be no such facts. The three postulates of Aristotle: 
identity, non-contradiction, and the excluded middle, 
are the basis on which all logic rests. But they them- 
selves are not susceptible of logical proof; they are 
indeed the basis of our sensory knowledge of brute facts. 
Thus they are empirical in the most radical sense. Our 
experience starts with the separation of a brute fact from 
its surroundings, and the recognition of it (a) as an 



142 WHAT SCIENCE REALLY MEANS 

identical fact, (6) as being not its environment, and (c) as 
having no zone common to it and its environment. 

All the formulations of logic, then, start with the brute 
fact of identity, without which nothing would be ex- 
perienced. But once abstracting identity and its implica- 
tions, logic treats the purely formal and abstract system 
so derived as itself a series of given facts, and proceeds to 
draw further inferences from them. Thus the major and 
minor premises of every syllogism are brute givens, 
corresponding to the accepted theories of the physical 
sciences, which hi turn rest on brute difference, just as 
the theories of science eventually rest on brute sensory 
fact. The ideal science of logic corresponds exactly to 
those sciences which have abstracted from actuality. All 
the propositions of logic are stated conditionally: if A 
then J3, just as all the abstractive laws of a science are so 
stated, e.g. if action then reaction. Thus both logic and 
natural science are free from actuality in their formula- 
tions but applicable to actuality conditionally. 

If logic is an empirical science, then so is mathematics. 
Mathematics is merely one kind of abstract extension of 
logic, rigidly depending upon the laws of logic, and thus 
finally resting upon basic difference. A large part of 
mathematics, however, depends upon assigning exact 
measurements to difference, Mathematicians try to arrive 
at the most general and abstract formulation of what 
appears experimentally as special mathematical formula- 
tion. The instantaneous speed of a moving object and 
the tangent of a curve are both generalized under the 

dy 
same formula, -, where y is indifferently the distance 



THE METHOD OF EMPIRICISM 143 

or the ordinate, and x indifferently the time or the 
abscissa. The fact that the generalization covers the special 
cases can only be proved experimentally. Thus all opera- 
tions in mathematics are experimental, even when they 
do not appear so. But in certain instances the method is 
more obviously experimental. The method of finding 
invariance under successive transformations in affme and 
projective geometry, and in the theory of groups, is that 
of performing operation after operation to find empiri- 
cally what properties of the system remain identical. 6 
Thus the theory of invariance is arrived at experimentally. 
To quote Felix Klein, the problem is 

Given a manifold and a group of transformations of the 
same, to develop a theory of invariants relating to that 
group. 7 

The fact that the operations of mathematics are so far 
removed from sense experience does not make mathe- 
matics one whit less empirical than chemistry. 

The statement that metaphysics is also properly an 
empirical science is apparently hard to accept. In fact the 
quarrel with metaphysics is just that it deals with absolutes 
which arc beyond demonstration. But when we take into 
consideration that metaphysics is a certain kind of 

6 But this is only what is done in every science: the accidental is 
discarded and the necessary retained. However, what is accidental for 
one department of science may be necessary for another. Black spots 
before the eyes are accidental for bacteriological analysis but necessary 
for medical diagnosis. Similarly, what is not invariant (i.e. changing) 
under a group of transformations also may be studied for change as 
itself an invariant. 

7 Cited by E. T. Bell, The Queen of the Sciences, p. 69. 



144 WHAT SCIENCE REALLY MEANS 

generalization and abstraction from actuality and brute 
fact, we shall more clearly see what its experimental field 
is. It is obvious that a metaphysical system which fails 
to check with the accepted theories of science and the 
facts of common experience is a bad one, and will never 
gain any lasting acceptance. The task of philosophy is 
made difficult by the very fact that its generalizations 
must embrace so much, and thus its conclusions are more 
tentative than those of the special sciences, since meta- 
physics must stand the test of all knowledge. But this 
fact does not mean that it is thereby rendered exempt 
from its proper empirical test. Agreement in philosophy 
is thus far a great deal harder to attain than in science. 
But random vagaries and vague mysticism .are no more 
philosophical for philosophy than they would be 
scientific for science. Moreover, every metaphysical 
system must be self-consistent, since this is everywhere 
the empirical test. And like science, new generalizations 
which are found to agree with the old are not sum- 
maries merely but throw light on new facts. Thus 
ontology, like the self-consistent systems of science, is a 
fact-finding instrument and not simply a systematic 
accounting and arrangement. 

To generalize from our investigation of empiricism in 
the various fields, the essential nature of empiricism is 
the limiting conditions of the speculative reason. Thus 
what appears as speculative from the immediately pre- 
ceding lower level of abstraction appears as empirical 
from the immediately following higher level. What is 
involved is a matter of direction and not one of intrinsic 



THE METHOD OF EMPIRICISM 145 

dissimilarity. The distinction between the empirical and 
the logical has been too severely drawn. All that em- 
piricism states is that nothing can be constructed except 
in and through lower levels of accepted fact, which, 
abstractive as they may be, finally rest upon the mere 
faith in the bruteness of given sensory experience. From 
the brute given upward indefinitely, all that matters is 
self-consistency and economy. Empiricism finally reduces 
to the question of relevance. 



CHAPTER VII 
THE LOGIC OF SCIENCE 

Nature syllogizes from one grand major 
premiss. . . . 

CHARLES S. PEIRCB 
INDUCTION AND DEDUCTION AS DIRECTIONS 

The close relationship between empiricism and logic 
has been indicated. It must now be further explored. To 
do so we must first examine inductive and deductive 
logic, and then show what these mean in terms of 
scientific method. Some scientists make the mistake of 
supposing that scientific method is exclusively a matter 
of induction, whereas others suppose, just as mistakenly, 
that scientific method is exclusively a matter of deduc- 
tion. A plague should be cried on both these houses. 
Scientific method requires both, and the validity of the 
one certainly requires no rejection of the other. The two 
methods are complementary and not antithetical. From 
the point of view of logical experiment, deduction is the 
process of drawing necessary conclusions from premises. 
Induction is the choosing of premises. 

What is induction? It is a process which starts with 
certain givens and moves to a generalization which will 
subsume them so that they appear as related parts of one 
system. The movement of induction is always in the 
direction of greater generality, from the less general to 
the more general. Irrespective of what mental aspect an 
induction is, it appears logically as a partial sublation of 



THE LOGIC OF SCIENCE 147 

otherwise unsublated data, and therefore as an explana- 
tion, since the explanation of anything consists in its 
being assigned a place in a system. 

What is deduction ? It is a process which starts with a 
given generalization or system and moves to find the 
parts of that system included as implications. The move- 
ment of deduction is always in the direction of lesser 
generality, from the more general to the less general. 
The explication of any system is all the deductions which 
can be drawn from it. 

We can see that the possibility of induction or deduction 
takes for granted the existence of both. Without data no 
induction could be made to a system; without a system 
no deduction could be made to implications. The move- 
ment in the first case is up from the parts to the whole; 
the movement in the second case is down from the 
whole to the parts. The main and important distinction, 
logically speaking, between induction and deduction is 
one of direction. 

We are trying to present a system of relations which 
is discovered by two methods : induction and deduction. 
The start can be made from any given system, and that 
system analysed into subsidiary systems, or synthesized 
with other systems into a more inclusive system. There 
are thus series or layers of systems, arranged in a hierarchy 
by order of inclusiveness, which the mind ranges over 
by running up inductively or running down deductively. 
Inductions always have a deductive background, whether 
this is recognized or not. 1 And what is induced to is 

1 "Practical inventions do not really come as 'bolts from the blue* 
to those who have never thought of or studied a given topic. . . . 



148 WHAT SCIENCE REALLY MEANS 

always another deductive level, whether this is recognized 
or not. 

The relevance, then, of any item to any other item can 
only be by reference to place within a system, and cannot 
refer to anything outside that system. This makes possible 
the investigation of a system in isolation, otherwise im- 
possible. If everything in the universe had to be taken 
into account in order to explain an item, explanation 
would be impossible. But explanation is made possible 
by confining attention to a given system. This fact 
defines relevance and irrelevance. We have already 
demonstrated relevance. Irrelevance consists in referring 
to something outside a given system as an explanation of 
something inside the system. For instance, the analysis of 
a dining-room table into legs, top, drawers, etc., does 
not involve the system of which the dining-room table 
is a part, e.g. other furniture in the room, or the room, 
or the economy of the household, etc. Therefore to bring 
in these wider systems in the analysis of the table is 
irrelevant. On the other hand, synthesis is impossible 
merely in terms of elements of analysis, since no number 
of items of a system can by themselves yield the whole 
system. For instance, the freedom of the will cannot be 

Even the celebrated case of James Watt inventing the steam engine 
after observing his mother's teakettle, breaks down when one dis- 
covers that other steam engines were already in use and that Watt 
studied the problem for years before he invented anything. One of 
the most spectacular strokes of genius in the nineteenth century, 
Hamilton's discovery of quarternions (which, as he has told us, came 
to him in a few seconds), is known to have been based upon twenty 
years of study of the very problem which he suddenly solved" 
(Gardner Murphy, A Briefer General Psychology, p. 358). 



THE LOGIC OF SCIENCE 149 

inferred from the Principle of Indeterminacy at the 
sub-atomic level. Nor can biological phenomena be 
entirely explained in physico-chemical terms. 

Induction and deduction constitute the movements of 
logic. But logic per se has nothing to do with anything 
moving. It deals with the conditions of possibility. 
Actuality we take to be the succession of sensory facts 
which can be experienced. The logical order of possi- 
bility is not a temporal succession at aU, but a set of 
unchanging conditions mutually implicative. All logical 
propositions are thus formal and have nothing to say 
about any actual thing or event. To apply logic, there- 
fore, in natural science, other factors than the purely 
logical must be considered, since science is concerned 
with determining the extent to which actuality is formal. 

THE LOGIC OF SCIENTIFIC METHOD 

Since science is concerned with actuality to the extent to 
which it is formal, scientific method must be a particular 
application of logic. 2 The very feasibility of the applica- 
tion of formal logic to actuality in scientific method pre- 
supposes the continuity, or what John Stuart Mill called 
the uniformity of nature. It takes for granted that nature 
is objectively a consistent system, continuous and uni- 

2 Since experimentation seems to deal with sensible qualities, and 
logic with formal qualities, the conception of the logic of science often 
appears to the experimenter to be a contradiction. But in successive 
experiments the sensible qualities change, whereas the formal qualities 
remain the same, and it is the latter which enable an experiment to 
be called scientific. The presence of the sensible qualities blind the 
experimenter to the fact that from his point of view the formal are 
prior. 



I 5 o WHAT SCIENCE REALLY MEANS 

form, which can be known. We have shown that logic 
deals only with possibility and not with actuality, and 
that scientific method deals with the verifiable possi- 
bilities of actuality. For instance, that all unicorns are 
horses having a single horn, is a proposition which has 
no application to zoology since no actual unicorns have 
ever been observed. In other words, both the major 
and the minor premises of a logical proposition are always 
ideal and conditional, i.e. possible. 

If unicorns arc hdrses having single horns, 
And if this horse has a single horn, 
Then this horse is a unicorn. 

But scientific method differs from formal logic in 
having as the minor premise an actual fact, i.e. in 
determining that the condition applies. And this is what 
experiment or demonstration is. 

If unicorns are horses having single horns, 
And since this horse is observed to have no horn, 
This horse is not a unicorn. 

The first syllogism is purely logical; the second corre- 
sponds to the procedure of scientific experiment. It must 
be noted that in both syllogisms the major premise is 
conditional and ideal. As far as deduction is concerned, 
the major premise is treated as given, and has empirical 
standing, having itself once been the minor premise of 
some other syllogistic movement. In science, inductions 
from observed facts, when mathematically formulable, 
have been employed to yield new results deductively. 
But the inductions from which this train of reasoning 



THE LOGIC OF SCIENCE 151 

started have often themselves later been shown to be 
deductions from some apparently unrelated deduction. 
For instance, Balmer's Law for the position of lines in 
the hydrogen spectrum was a mathematical induction 
from certain observed measurements. Since this time 
the law has been deduced from wider systems : atomic 
theory and quantum mechanics, which have been shown 
to include Balmer's Law as a special case. 3 

Scientific method, in contradistinction to logic, in- 
volves two procedures: it goes down to be tested 
against actuality; it goes out to be tested against a 
given system for logical consistency. Thus again it is the 
logic of actuality. On p. 132 above we showed that 
Einstein's general theory of relativity was demonstrated 
in two ways: by testing against actuality in the three 
experiments noted; and by logical consistency, showing 
that it agreed with the previous body of physical 
knowledge. The test by actuality or experimental 
demonstration is not a proof of the validity of the 
scientific hypothesis involved; it is merely an allowance; 
whereas the failure of the empirical allowance of an 
hypothesis does constitute an absolute disproof. 4 It 
should be noted that the appeal to prediction is one form 
of the appeal to actuality. The test by consistency with 
logical possibility is proof. For proof means the ability 

3 We owe this illustration to Morris R. Cohen, Reason and Nature, 
p. 120 f. 

4 On page 150 we gave an example of the syllogism of disproof. 
We may also give here an example of the syllogism of allowance. 

Perhaps all frogs hop, 

Certainly some (all observed) frogs hop, 

Therefore it has not been disproved that all frogs hop. 



152 WHAT SCIENCE REALLY MEANS 

to place a given item, in a system where it will form part 
of a larger system without disturbing its consistency. 
Thus empirical proof is allowance; logical proof is proof. 5 
Chantecler's theory that he crowed up the sun was not 
proved by the many times that the coincidence happened, 
but was absolutely disproved by the one time that it 
didn't. As Jeffreys says, 6 "one of the chief functions of 
exceptions is to improve the rule." 

The two procedures can be validly conducted without 
reference to actuality solely on the level of possibility. 
This is what happens in the science of mathematics, 
where the proof of logical consistency and the test by 
experimental demonstration turn out to be identical. 
The only possible tests in mathematics are to verify the 
consistency of a given mathematical hypothesis by 
reference to sub-systems, or to wider systems. That is 
what experiment means in mathematics. 7 

But the two procedures cannot be validly conducted 
solely on the level of actuality and without reference to 
possibility. Here the two movements are not the same. 
For to transport the two procedures to actuality means 
that the major premise of the syllogism which cor- 
responds to experimental demonstration must also be an 
actual. When this is done, the procedure down to 
experimental demonstration is retained, but its logical 
consistency is omitted, and what results are so-called 

5 Cf. the instance of Balmer's Law, p. 151, where induction is 
eventually shown to be a special case of deduction from a more in- 
clusive induction. 

6 Harold Jeffreys, Scientific Inference, p. 5. 

7 For a good illustration of this, see H. Levy, The Universe of Science, 
p. ii6f. 



THE LOGIC OF SCIENCE 153 

empirical laws, generalizations from observed phenomena 
which may or may not hold as laws. 

England was prosperous under Elizabeth, Anne, and 

Victoria, 

England is always prosperous under queens, 
Therefore England will be prosperous under the next 

queen. 

Or, formulated deductively, 

Prosperity under Elizabeth, Anne, and Victoria means 

prosperity under all queens, 
Queen X is a future queen of England, 
Therefore England will be prosperous under Queen X. 

This is an empirical law which, like all other empirical 
laws, holds only with exceptions. It is therefore not a 
scientific law. The next queen may disprove it. The 
difficulty lies in the lack of logical consistency, there 
having been no necessity shown between the sex of the 
monarch and the prosperity of the realm. If such necessity 
could be shown, it would take the form of a logical 
proposition and not of an actual fact. No exception can 
prove a rule; but on the contrary any exception can 
disprove it. 

It is therefore true that all scientific laws must occupy 
the status of ideality, of possibility, and cannot be mere 
generalizations of actual facts. 

Experiment is a variety of deductive logic, that variety 
where the determination of implications involves refer- 
ence to the observation of actuality. But logical analysis 
equally involves experiment, though here the experi- 



154 WHAT SCIENCE REALLY MEANS 

ments performed do not candidly present themselves as 
such. For instance, the analysis of the term 'queens' or 
the term 'prosperity' cannot be made without reference 
to a typical case. Such reference constitutes a logical 
operation. Experiment is involved in logical analysis, 
and logical analysis is involved in experiment. The proof 
by deduction and the proof by experiment turn out to 
be the exploration of what is involved in a system (i.e. 
its implications) so that all the parts of the system are 
seen as consistent parts of a larger system. 

Those who say that analysis or deduction is the whole 
of scientific method have been misled by too narrowly 
considering scientific procedure, which always analyses 
to establish an hypothesis. They have neglected to per- 
ceive that no analysis can be effected except in terms of 
an embracing system, and that such systems are not 
merely given to ordinary observation, but require in- 
sight and valid induction. 

ANALYSIS AND SYNTHESIS 

We have shown the two movements of logic in scientific 
method and the absurdity of trying to confine scientific 
method to either movement. The difference between 
induction and deduction is a difference of direction, so 
that what is an induction from one level is a deduction 
from a higher. The same thing applies mutatis mutandis 
to the question of reason and empiricism, where reason 
alone or empiricism alone is championed to the exclusion 
of the other. It has been shown that any theory arrived 
at by speculation may become an empirical fact, and is 
ipso facto an empirical fact when deduced from a higher 



THE LOGIC OF SCIENCE 155 

level. Thus what is speculative from one level is em- 
pirical from another, and again what is involved is a 
matter of direction. The further problem of the dif- 
ference between pure and applied sciences is resolved in 
the same manner, by showing that there is no absolute 
distinction but only a relative one. 

The exclusive reliance on rationalism or empiricism 
produces a pair of dogmatisms. Rational dogmatism con- 
sists in the assumption that it is possible to reason to the 
facts without the aid of experimental demonstration. 
Plato's dogmatic rationalization that the universe being 
harmonious, there must be harmonic intervals between 
the planets, was overthrown by the empirical observations 
of Tycho Brahe. The mistake lay in supposing not that 
there was a regularity, but that the particular regularity 
could be found by deducing from the larger system. 
Empirical dogmatism, on the other hand, consists in the 
assumption that it is possible to discover laws without 
the help of the speculative reason. The social scientists 
working from this position have been accumulating ex- 
perimentally determined facts for decades, without 
having been able to produce a single valid law (from the 
very fear of being too speculative). 

Rational dogmatism and empirical dogmatism are 
each half-truths and half-errors. The truth of rational 
dogmatism consists in the fact that reason is required as 
pointing the way down towards discovery, without 
which there could be no discovery. The truth of empirical 
dogmatism consists in the fact that without experiment 
the nature of the constituents of a system can never be 
known (no number of theories being able to prove an 



156 WHAT SCIENCE REALLY MEANS 

actual). The error in rational dogmatism consists in the 
truth of empirical dogmatism, and vice versa. Rational 
dogmatism is uncontrolled speculative generalization; 
empirical dogmatism is positivism. One never touches 
the ground; the other never leaves it. Scientific method 
cannot be confined to either but must employ the truth 
that is involved in both, in a complementary manner. 
Where empiricism and speculation are seen as two 
directions, it becomes clear what the limits of each are. 
Since the explanation of anything lies in showing its con- 
sistency within a larger system, speculation about that 
larger system is the first requisite. But the placing of the 
parts of the smaller system within that smaller system is 
irrelevant to the larger system. And thus the second 
cannot be deduced from the first. 

Equally, it is impossible to find a system which explains 
the parts of analysis of the parts, since this is looking in 
a lower system for an explanation of the higher. The 
attempt to jump from the constituents of one system to 
another system either higher or lower is misleading and 
fallacious. 

We now come to the relative distinction between pure 
and applied science. Sciences cannot be divided into those 
which are pure and those which are applied. Some 
sciences appear to be merely applied sciences; their 
theories are not in evidence because they are overlooked 
or have not been formulated. Agriculture is an example. 
Other sciences appear to be pure or merely formal because 
little or no application has been found for them. For 
example, many branches of mathematics have remained 
notoriously pure, i.e. no use has as yet been found for 



THE LOGIC OF SCIENCE 157 

them. But scientific progress has moved two ways: 
toward the abstract formulation of applied techniques, 
and toward the application of pure formulations. The 
practice of medicine which was altogether and is still 
somewhat an e^Trcipia is daily becoming more of a 
rex^, as is also cookery, business management, etc. 
On the other hand, conic sections, non-commutative 
algebra, and the tensor calculus were once branches of 
purely formal science, for which applications were later 
found. 

Within any given science, every abstractive level 
appears as formal to the level below it, and as applied to 
the level above. Physics appears as 'formal 5 to technology, 
and mathematics appears as 'formal* to physics. Con- 
versely, technology appears as 'application' to physics, 
and physics appears as 'application' to mathematics. 
Thus so apparently useful a discipline as technology is a 
formal study from the point of view of its application 
to industry. And so apparently abstract a study as higher 
mathematics is an applied affair from the point of view 
of logic. 

We have in this section been exhibiting a single point 
which appears under several guises, namely, that there 
are levels of investigation which require two directions 
to be fully understood. Only one direction can be em- 
ployed at a time, but both must finally be employed in 
each instance of scientific method. We have seen this point 
illustrated in the question of induction and deduction, 
rationalism and empiricism, pure and applied science. But 
in science, this quasi-opposition is more familiarly known 
as the problem of mechanism versus teleology or purpose. 



158 WHAT SCIENCE REALLY MEANS 

MECHANISM AND PURPOSE 

Mechanism and purpose in science are merely the general 
doctrines covering the questions of analysis and synthesis, 
the employment of empiricism, and the speculative 
reason. Mechanism in science states that the explanation 
of die phenomena of nature requires only an analysis 
of given items into constituent parts, and that such 
an explanation exhausts the phenomena without the 
introduction of purpose. Purpose, it further states, is an 
unnecessary and thus an illicit conception, and efficient 
causation is alone scientific. Those who oppose this 
doctrine maintain that many of the phenomena of 
nature cannot be explained without introducing the 
category of purpose, and final causation. Purpose in 
science is the statement that any given item contains 
more than the sum of its parts. 

Mechanism is known as atomism, materialism, "physi- 
calism," etc. Atomism is the variant which may be 
defined as the belief that all things are the results of un- 
changing particles in motion; materialism, that matter 
alone is real, and all else configurations of it; and physi- 
calism, that all the sciences are reducible to the science of 
physics. Purpose is known as vitalism, creative evolution, 
entelechy, etc. Vitalism is the variant which may be 
defined as the belief that a mysterious binding quality, 
called life, is involved in living organisms beside their 
material parts; creative evolution, that there is a force, 
e.g. the elan vital, which is the 'drive' working within 
things toward some mysterious end; and entelechy, that 
there is a mysterious determining principle germinating 
within things to guide them toward an end. 



THE LOGIC OF SCIENCE 159 

Both these doctrines fail to be completely explanatory 
of scientific method or of the data with which the 
sciences deal. Mechanism accounts for analysis well 
enough, but fails to account for wholes which defeat 
every effort to build them up with elements of analysis 
alone. Purpose accounts for organizations well enough, 
but begs the question of constituent parts which cannot 
be accounted for by purpose. It is quite understandable 
why most scientists should consider that purpose is not 
properly part of the procedure of science, since it does 
not appear under this guise. Purpose appears in scientific 
analysis not as purpose but as empirical fact, and it is 
only recognizable as purpose in regard to systems above 
it. For instance, in the analysis of blood, blood appears 
as an empirical fact, a brute item for analysis, and it is 
only with reference to the function of blood that one can 
recognize this empirical fact to be also a purposive affair 
in regard to the nourishment of tissues, etc. In isolating 
an item for analysis, it is forgotten that the only canon 
of isolation in the first place was its purpose. Function is 
purpose, and function defines an item. 

The inception of any single application of scientific 
method presupposes an hypothesis or an induction (pur- 
pose) at once predicated and left behind. The scientist is 
mainly concerned with exploring the deductive implica- 
tions of an hypothesis, and thus he tends to forget the 
original leap to the predicated purpose. It is not easy to 
see a scientist leap to an hypothesis in the bathtub, but 
anyone can actually observe him working in the 
laboratory exploring deductive implications. The fact that 
mechanism is indefinable without purpose is well shown 



i<5o WHAT SCIENCE REALLY MEANS 

when we consider the definition of a machine. A machine 
is a purposive organization of parts and not a mere 
agglomeration. 

On the other hand, die presence of purpose in scientific 
method does not mean that the vitalistic theories are 
valid. Purpose is not a mysterious something added to 
empirical entities to give them 'meaning.' It is the relation 
which the parts bear to a whole. Necessarily such 
organization is abandoned in analysis. But this does not 
mean that it does not continue to exist. Water is not 
composed of oxygen, hydrogen, and wetness, but of 
oxygen and hydrogen in certain proportion and organi- 
zation, which is water and, as such, wet. Since purpose 
is, then, the organization of parts, it is not to be found 
in the parts alone; it is the whole of a system and not 
any part. Thus the attempt to find a life principle, an 
entelechy, etc., in analysis is an absurdity. 

Both mechanism and vitalism are each partly true, 
though each in itself is false if taken as being the whole 
truth involved. Both mechanism and vitalism, as false, 
point the same moral as the exclusive claim of analysis 
and synthesis, namely, that of trying to account for the 
whole of scientific method by one direction instead of 
by two. Mechanism and purpose yield the same caution: 
it is impossible to move from the parts of one system 
outside that system. Mechanism as an exclusive theory 
wrongly supposes that the sub-systems of parts can yield 
the system which includes those parts. Purpose as an 
exclusive theory wrongly supposes that a system which 
embraces given systems as parts can be brought in to ex- 
plain the parts of the embraced systems. An example of 



THE LOGIC OF SCIENCE 161 

the first error is the proposition that life is a property of 
the carbon atom. An example of the second error is the 
proposition that the elan vital works on the carbon atom 
to produce living tissue. 

In conclusion it should be pointed out that mechanism 
as a method in science is the essential element, since every 
purpose is explained only in terms of elements of analysis 
in relation to a system, i.e. for science purpose is die 
explication of the how. But the positivistic reading of 
mechanism as a scientific philosophy would exclude pur- 
pose, and therefore if followed logically, exclude also 
induction and hypothesis. It would thereby prevent all 
advance. Mechanism is just as vicious as purpose when 
erected into a scientific philosophy. In science what 
appears as purpose is rightly considered in its empirical 
aspects, i.e. analysed down, and when so analysed kept 
clear of higher systems. This is the empirical method. 



DEDUCTION VERSUS IMAGINATION 

With the understanding that deduction alone is insuffi- 
cient in science, and that purpose is implicitly involved 
in the start of analysis, we shall attempt to show that the 
direction of the development of science involves a greater 
and greater use of deduction and a lesser reference to 
purposive entities. 

With the development of a given science inductively 
the consistent logical system becomes by definition wider. 
This means that higher levels of abstraction are being 
attained, and that the appeal to actuality for allowance 
or disproof becomes less and less necessary. When a 



162 WHAT SCIENCE REALLY MEANS 

science is in this advanced stage of development, it has 
resort largely to mathematical formulation; its deductions 
yield brilliant results, often more brilliant than those 
attained through induction. Induction is not abandoned 
when a science advances to the mathematical stage, but 
it becomes less apparent, and requires less imaginative 
flight, approaching closer and closer to the process of 
deduction. 

We have shown that in mathematics the empirical 
proof can be either deductive or inductive, and that both 
are experimental. The place of brilliant insight in the 
advance of science has perhaps been over-emphasized, 
particularly in the more developed sciences. Brilliant 
results do not necessarily mean brilliant insight. Emile 
Meyerson points out that many of the discoveries which 
have been arrived at by deduction could never have 
been the results ot imaginative insight, since they are too 
fantastic ever to have appealed to any scientist. The 
superhuman vision obtainable with the photo-electric cell, 
is the application of a deduction from sub-atomic physics, 
and is certainly one which could never have been 
imagined. The same is true of television. None of these 
is as remarkable a feat of scientific imagination as the 
public assumes. They are clever adaptations of deductions 
from known principles. 

Admitting, however, that great scientific discoveries 
have been made inductively, through psychological in- 
sight, does not logic play a large part here as well ? Are 
not scientific discoveries as much a function of the given 
stage of a science's development as of the imaginative 
capacity of the individual scientists ? Certainly successful 



THE LOGIC OF SCIENCE 163 

scientific leaps in the dark' are not made by those 
ignorant of the background of the scientific system. They 
are not made by poets and prophets but often by scientists 
otherwise prosaic and unimaginative. Scientists who make 
brilliant guesses do so because of their knowledge of the 
consistent system which presents itself as a series of de- 
ductions. The logical status of a science is important in 
the understanding of scientific discovery and advance. 
The rapid advance of physics as contrasted with social 
science is certainly not to be explained by supposing that 
all the genuises have become physicists and that social 
science has in its service only mediocre intelligences. 

The development of a science to the level of abstraction 
which is fit for mathematical formulation accomplishes 
something else of value. It reduces to a minimum mytho- 
logic entities, which are the cryptic introduction of pur- 
pose into scientific analysis. For instance, medical science 
which has not reached the stage of physics or chemistry 
is cluttered up with such mythologic and crypto- 
purposive entities as immunity, resistance, defence, anti- 
body, agglutinin, lysin, etc. The scientific problem con- 
cerns the analysis of these entities into their mechanisms. 
They are useful, but only in the intermediate stages of 
science. In a mathematical-deductive science, like physics, 
purpose appears as the geometric properties of an arith- 
metic system. 

Thus induction and purpose do not disappear in the 
development of a science, but begin to become one with 
deduction and mechanism. In the ideal science all prin- 
ciples appear arranged ad seriatim as deductions from a 
single grand major premise. And purpose is seen as the 



164 WHAT SCIENCE REALLY MEANS 

hierarchy of the organizational series of systems in one 
system. 

HOW SCIENCE SHOULD PROGRESS 

We have been presenting the logic of science as direction 
of movement in scientific discovery. Induction, synthesis, 
purpose, hypothesis, arc all indicated as the directions up 
toward the more embracing, or that which embraces. 
Deduction, analysis, mechanism, empirical proof, are all 
indicated as the direction down toward the less embracing, 
or that which is embraced. These movements of dis- 
covery imply an order of existence to be discovered. This 
order of existence considered by itself cannot properly be 
called a direction or movement, since it does not change. 
It is a completely independent system, a hierarchy of 
embracing and more embracing functions, which are 
therefore independent of any method of discovery. It will 
be recognized that this must be the case, since we have 
shown that what is an induction from a given set of 
data is a deduction from another seemingly unrelated 
induction. Thus induction and deduction are seen as 
different approaches to the discovery of the same set of 
conditions. 

This independent set of conditions or, as we have 
previously termed it, this hierarchy of functions, may be 
compared with a spider web, in which the concentric 
threads form a dense manifold. Each thread embraces 
all threads below it as themselves less embracing. The 
investigator is the spider, not as the spinner of the web 
but as the one who can move over it, but only in one 
direction at a time. Obviously, when the spider is in a 



THE LOGIC OF SCIENCE 165 

shorter orbit, all outer orbits are to the spider more 
embracing or 'up' in the series; but when the spider 
moves to an outside orbit the shorter orbits are less 
embracing or 'down' in the series; yet they remain 
unchanged by the spider's position. The logical order of 
existence is independent of the method of its discovery. 
But obviously the method of discovery must conform 
to the logic of that which is to be discovered. 

In the conception of scientific method which we have 
been setting forth, given a dense hierarchy of functions, 
empiricism is the proof by logical consistency downward, 
a checking over of included systems to show that the 
more inclusive system from which the investigation 
starts is logically a system of those systems. We have 
further shown that whether this proof takes the form of 
experimentation candidly, or of deduction abstractly, 
the method is the same, requiring both logical con- 
sistency and experimental verification. In some cases 
these are identical. 

The way that science has progressed is not the ideal of 
science. The ideal method which should obtain and which 
begins to obtain whenever a science approaches a certain 
stage of development, is quite something else. When 
large inclusive systems are reached in a science, every 
other system must be shown to be a deduction from it, 
and lesser systems deductions from those, ad seriatim, 
until the whole system is seen as a pattern which inter- 
laces, and thus no item appears as disconnected from the 
rest. Granting that such an ideal could be approached, 
the need for allowance or disproof by reference to 
actuality must become less and less requisite, and proof 



166 WHAT SCIENCE REALLY MEANS 

by logical consistency serve the task of both proofs. 
The more that is known of a system, the less investigation 
is required to determine whether a newly discovered item 
is or is not a part of that system. Just as a nearly com- 
pleted picture puzzle is easier to complete the more 
nearly it is completed, because the remaining pieces are 
readily found to fit, so it is easier to determine where a 
new piece of knowledge will fit in the scheme of modern 
mathematical physics. And the reverse is true of the 
effort to determine the place of any item of knowledge 
in such an unorganized science as political economy. By 
the same token, it follows that the imaginative genius 
required to initiate a science is far greater than that re- 
quired to help it to progress after it has reached a certain 
stage. 

The ideal science presupposes the completion of the 
discovery of an already existing system. Obviously, 
there is as yet no such science, and it is of little practical 
help in producing one to refer only to what one ought 
to be when completed. Yet for the perfection of working 
method it is necessary to know what the ideal is. The 
ideal working method of science is the subjection of every 
hypothesis, after empirical proof, to subsumption by a 
more inclusive hypothesis which shows it as a special case 
of the more inclusive, i.e. as a deduction from it. The 
movement is, therefore, in widening concentric circles, 
so that the older and lesser hypotheses arc shown to be 
more restricted than was formerly supposed, but per- 
fectly valid within limits.Thus no scientific theory is ever 
truly abandoned, as it would seem to those ignorant of 
scientific method. The advance of science does not stagger 



THE LOGIC OF SCIENCE 167 

from extreme to extreme, abandoning one direction in 
favour of another, like the practice of politics, but rather 
resembles the concentric waves in a pond which widen 
out after a stone has been dropped. Human ignorance 
restricts at any given time what the last and most in- 
clusive circle shall be; and it is not until contradictions 
appear to universal claims that men are led to seek for 
more inclusive circles which will reconcile it and give it 
proper limitations. This is the best that any human 
endeavour can expect to accomplish. 



CHAPTER VIII 

CAUSALITY AND PROBABILITY 

In point of fact statistical laws are dependent upon 
the assumption of a strict law of causality functioning 
in each particular case. 

MAX PLANCK 
EMPIRICISM AND CAUSALITY 

More is involved in the logical nature of empiricism 
than the strict question of induction and deduction. The 
problem of causality arises. That the idea of causality is 
involved in empiricism is well shown by the fact that 
all radical empiricists or philosophical positivists deny 
that causality is an objective fact of nature. Just as the 
idea of causality is denied by those who see science as a 
"compendious representation of the actual," so the 
understanding of science as a purely abstract domain 
requires causality. 

Throughout this book we have been gradually demon- 
strating the existence of a logical series of functions, 
independent of observation and mutually implicative. If 
the radical empiricists are correct in their contention that 
causality has no objective status, then such a realm of 
functions as we predicate is challenged and held to be a 
merely mental construction which has no necessary cor- 
respondence to nature. This would make nature an 
irregular and irrational affair, and would leave as an 
insoluble puzzle the question of how it could be investi- 
gated by the minds of men. Nevertheless, P. W. 



CAUSALITY AND PROBABILITY 169 

Bridgman for one does not hesitate to make the bold 
assertion that the universe is just this kind of unintelligible 
affair. He says, 

The world is not a world of reason, understandable by the 
intellect of man, but as we penetrate ever deeper, the very 
law of cause and effect, which we had thought to be a formula 
to which we could force God Himself to subscribe, ceases to 
have a meaning. 1 

In refutation of this position, there is little more to add 
to what has already been said in Chapter in. Let us only 
repeat that if the world is as irrational as Bridgman pre- 
dicates, then his predication has no standing as true or 
false. But even if we accept his argument, then the very 
universality of irregularity implies a kind of dependability 
upon regularity. Thus irregularity for the totality of the 
universe is a contradiction. 

Aside from such extreme statements as Bridgman's, 
however, there is a general tendency on the part of 
physicists and, by consequence, other scientists, to doubt 
the existence of causal laws in nature. Eddington, for 
example, asserts that causal laws are truisms, but that 
statistical laws are real laws which in high averages have 
given the appearance of causal laws. This rejection of 
causality implies a rejection of ideal entities, since causal 
laws must all be framed in terms of such entities. If 
causal laws are mere appearances, ideal entities have only 
a fictional value. Lenzen makes the statement that 
classical physics deals with ideal entities, like "ideal 

1 P. W. Bridgman, "The New Vision of Science," in Harper's for 
March 1929. 



170 WHAT SCIENCE REALLY MEANS 

particles, ideal rigid bodies, ideal fluids," 2 whereas 
modern physics is purely mathematical. The term 
'ideal' has unfortunate connotations; it is supposed to 
mean subjective, imaginative, unreal. But what it denotes 
is a set of conditions abstracted or isolated from actuality 
and only approximated to in actuality. The mathe- 
matical symbols, co,X, 8,A, are just as ideal as chemically 
pure iron, absolute rigidity, etc. An ideal proposition is 
one to which no actual has been assigned. The whole 
present misconception that science has abandoned ideal 
formulations and, as a consequence, causality, rests on 
the inability to see that mathematical symbols are merely 
better substitutes for the older ideal entities. We have 
shown that the nature of such ideal entities was merely 
mathematical, and that the pictorial representation of 
them was unnecessary and misleading. But to state that 
science has taken an entirely new tack because of the 
elimination of such pictorial representations is evidence 
of a lack of understanding of science itself. 

The idea of causality only seems to have been dropped 
by modern science. There is no categorical distinction 
between classical physics and modern physics. There has 
certainly been an advance, but in the direction of greater 
generality and emphatically not in basically logical pro- 
cedure. What appeared in classical physics as causality 
appears in modern physics as function. And it is only 
because the nature of causality was misunderstood in 
classical physics, and has since been given a new name, 
that it seems to have been abandoned. The question of 
probability versus causality is one of the argumentative 
2 V. F. Leiizen, The Nature of Physical Theory, pp. 44-5. 



CAUSALITY AND PROBABILITY 171 

by-products of the misunderstanding of the integral 
history of science. Its occasion, however, is irrelevant to 
the logical question of causality, as we shall later show. 
Causality properly understood by whatever name is 
implicit in modern as well as in classical physics. 

CAUSALITY AND CONTINUITY 

Let us leave the subject of causality for a moment and 
discuss the manifold of natural phenomena as it is as- 
sumed everywhere in science. The "uniformity of nature" 
means a series such that between any two items in the 
series a third can always be found, and such that in any 
definition of an item of the series the beginning and end 
of the item are the end and beginning of adjoining items 
in the series. Continuity "is the absence of ultimate parts 
in that which is divisible." 3 It is "nothing but perfect 
generality of a law of relationship." 4 

In terms of science this means, first, that there are no 
ultimate constituents of the universe, but that every 
quasi-element of analysis is subject to further analysis in 
an unending series, whether such analysis has yet been 
accomplished or not. Secondly, it means that there is 
always a system more inclusive than any given system, 
whether such a system has been found or not. In short, 
the doctrine denies that nature is discontinuous, and that 
finitude has any limits. There are no final irrational ele- 
tional elements, no brute givens, even though there will 
always at any time be what appear as brute facts. Such a 
doctrine is radically insusceptible of proof, yet its ac- 

8 Charles S. Peirce, Collected Papers, 6.173, 
4 Ibid., 6.172. 



172 WHAT SCIENCE REALLY MEANS 

ceptancc is tacit in scientific procedure. Thus the mole- 
cule was superseded by the atom, and the atom, that 
supposedly indivisible entity, was superseded by the 
quasi-ultimate particles, electron, proton, neutron, etc. 
We take it that science in general will not accept the 
indivisibility of these entities any more than it did that 
of the old 'atom/ 

Similarly, no system, however inclusive, has persisted 
as the final system for very long, but one more inclusive 
has always been found to take its place. Newton's 
cosmology was supplanted by the relativity cosmology; 
and we take it as axiomatic that science will not accept 
as final even the relativity cosmology. Thus science 
accepts nothing as brute and final except pro tern, and of 
necessity. 

The definition of continuity as the perfect generality 
of a law of relationship means in science that the ac- 
ceptance of law is equivalent to the rejection of the 
possibility of exception. As a practical matter, this indi- 
cates that what will apply to a given number of instances 
will apply to all instances, if the abstraction of instances 
has been fairly made. It indicates also that a given 
principle remains the same though it appears conditioned 
in various ways. When Galileo generalized the law of 
falling bodies, the principle of the inclined plane, and the 
principle of the pendulum, all into one principle: the 
law of inertia (to use Newton's later terminology), he 
was presupposing the continuity of nature. That the as- 
sumption was not unfounded, need not be argued. In 
fact, it may be said that without the assumption of this 
principle the whole of science would be at best a 



CAUSALITY AND PROBABILITY 173 

description of how certain particular experiments re- 
sulted. Science would be a partial history and not a basis 
for prediction. 

What do all these definitions of continuity mean in 
terms of causality ? We have shown that continuity in 
science means the rejection of anything ultimately un- 
analysable or ultimate. Science finally refuses to believe 
that any finite tiling is just a brute fact without reason, 
or that any event is uncaused. To put this in the ter- 
minology of cause-and-effect, it means that the minutest 
elements of analysis at any stage are the result of still 
more minute elements and, conversely, that the largest 
system which has been discovered at any stage is the 
effect of more inclusive systems. Moreover, the ac- 
ceptance of a principle as operative without exception 
throughout its sphere of applicability is tantamount to 
the declaration of inexorability, which is to say, strict 
causality or causal law. In fact, there is no difference 
between the acceptance of the principle of continuity or 
the uniformity of nature, and of strict causality. He who 
accepts one is perforce driven to the other. The scientists 
accept causality by accepting the continuity and uni- 
formity of nature. And the fact that they do so im- 
plicitly, without awareness of the multiple implications 
in which they are involved thereby, does not change the 
situation. Thus every scientist in so far as he is a scientist, 
and despite his protestations, accepts causality. 

CAUSALITY IS NON-TEMPORAL 

Why, then, do the scientists suppose that causality has 
been abandoned in science ? The answer is that the idea 



174 WHAT SCIENCE REALLY MEANS 

of causality has been persistently misunderstood as 
meaning the determinism of history, a locked sequence 
of actual happenings. Hume, for instance, denied that 
there was any continuity, or that there was anything more 
than a sequence of events which by itself manifests no 
causal nexus. John Stuart Mill, however, formulated 
even more succinctly the point of view of the strict 
mechanistic scientist of the Newtonian era. He defined 
causality as the aggregate of all the circumstances under 
which an event occurs. 5 It is this understanding of causality 
as temporal which modern science has rendered un- 
tenable, and which therefore seems to indicate to the 
scientists that causality has been overthrown. 

The most notorious instance of the failure to predict 
actual occurrences is the behaviour of an actual sub- 
atomic particle. But if causality had been properly 
understood in the days of classical physics, it could have 
been demonstrated that the inability to predict any actual 
occurrence with absolute exactitude was due to ignorance 
of some of the factors involved. When an experiment is 
performed to demonstrate a law, the attempt is made to 
isolate a system for analysis. Perfect isolation, however, 
is never accomplished, because 'controlled conditions' 
cannot be absolutely controlled. Thus every actual ex- 
periment will bear out a law only approximately, though 
often with very minute variations. 

The application of general principles to actuality must 
always admit of modifications, which modifications do 
not serve to nullify the invariability of the principle but 
rather serve to modify the actual effects produced 

6 John Stuart Mill, System of Logic, book iii, chapter 5. 



CAUSALITY AND PROBABILITY 175 

thereby. Indeed, it is in terms of an unchanging principle 
that the modifications themselves must be understood. 
Strict causality cannot be demonstrated because it does 
not occur pure in demonstration. But this is no proof of 
its non-existence as pure. Indeed, the fact that its work- 
ings can be approximated to in an experiment under 
properly (i.e. the most perfectly) controlled conditions 
is an argument for the existence of causality, and not the 
reverse. 

Let us see if 'the aggregate of all the circumstances 
under which an event occurs' can properly be called 
causal. Suppose that the chairman of a meeting strikes 
the desk with his gavel, causing ripples in a glass of 
water on the desk. The desk had just been painted brown; 
the weight of the gavel was seven ounces; at the time 
the event occurred the room was full of people; the 
initial velocity of the blow was one foot per second; the 
room temperature was 85 degrees Fahrenheit; the dis- 
tance from the glass to the place where the gavel struck 
was sixteen inches; the day was Tuesday in the month 
of March; the place, Wichita, Kansas. Note that the 
effect is the rippling of the water in the glass. We have 
mentioned only a few of the vast aggregate of all the 
circumstances under which the event occurred. How 
many of these circumstances bear on the effect as its 
cause ? Causally are they all of equal importance, merely 
by virtue of their participation in the aggregate ? Obvi- 
ously, the initial velocity of the gavel was of more 
importance than the temperature of the room. Certain 
conditions, such as the day of the week, can plainly be 
ruled out as causes. Without labouring the point, it is 



iy6 WHAT SCIENCE REALLY MEANS 

clear that the cause of an event cannot be the aggregate 
of all the circumstances under which that event occurs, 
but must be certain of the circumstances. 

What, then, is the canon of selection whereby certain 
circumstances can be called causal and others not ? The 
canon is one of relevance, and the relevance of a physical 
event can only be to a physical system. Thus velocity, 
mass, and temperature may be relevant, but date, location, 
colour, and social surroundings can have no relevance. 
But once admitting only physical factors as causal for a 
physical event, the main cause, of which the others are 
merely modifying causes, still remains to be isolated. 
And this can be found only through a general principle 
known or discovered by experiment. Experimentation 
in this connection is seen to consist in the reproduction 
of the event with certain factors omitted and certain 
kept. When the paring down of circumstances reaches 
the point where the omission of any more prevents the 
event from happening, then cause has probably been 
found. The true cause of the trembling of the water 
must be laid to the mechanical principle of action and 
reaction. A cause will always reduce to a matter of abstract 
function. 

Going back to the actual event, can it be said that any 
factor was the cause of the rippling of the water before 
the event took place ? Suppose we take as an hypothetical 
cause die momentum of the gavel at any time before it 
struck the table. Then the hypothetical cause was still not 
absolutely certain, since many chance factors could have 
intervened to prevent the gavel hitting. The hypothetical 
cause was only a probability, growing stronger and 



CAUSALITY AND PROBABILITY 177 

stronger as the time interval was cut down. When that 
time-interval reached zero, the probability of the event 
happening reached absolute certainty. When event A 
approaches event B as a limit, probability reaches cer- 
tainty as a limit. But when event A and event B have the 
intervening time element eliminated, they are not two 
events but one, AB, in which the distinction between 
A and B has been made not on a temporal but on a 
logical basis. Thus cause and effect are seen as a logical 
nexus and not as a temporal sequence. Causality asserts, 
if A then B. In this particular case, if action, then re- 
action. This means that two functions are involved in 
one function, i.e. that two functions have been analysed 
as parts of a single function. 

Here causality shows its true nature as the deduction 
from premises. Causality rightly understood means that 
every function is included or is the deductive consequence 
from a more inclusive function, i.e. is the effect. In other 
words, it means that the more inclusive function is the 
cause. When cause and effect are considered in actual 
happenings, it is the more inclusive function which 
determines the lesser, and which is segregated as the cause. 
Causality in actuality exhibits the logical order running 
through the temporal order. To the extent to which one 
is able to segregate out the logical element in any situa- 
tion, that situation will be understood and subjected to 
control. In a comparatively well-developed science, the 
employment of mathematics means the widening of the 
knowledge of the logical order at that level of investiga- 
tion. Cause and effect appear explicitly as functions. Thus 
in advanced science, causality seems to be left out. But 



178 WHAT SCIENCE REALLY MEANS 

what is left out is only the old error of formulating 
causality as a temporal affair. 

PROBABILITY REQUIRES CAUSALITY 

The occasion for the apparent abandonment of causality 
as a principle in modern physics (and a fortiori in all other 
sciences) is the vogue of statistical laws. Modern phy- 
sicists, assuming that causal laws are coercive, and 
demonstrating that invariance does not exist in actuality, 
wish to substitute the idea of probability for that of 
causality. Causal laws, they inform us, are too rigid, 
whereas statistical averages merely yield a formulation of 
what is likely to happen, and thus the concept of proba- 
bility instead of strict causality reigns. 

Can probability be accepted as supplanting causality? 
In order to answer this question it will be necessary to 
make an analysis of probability. Abstractly understood, 
what is it? Probability is the asymptotic approach to 
certainty. Certainty is the predication of absolute in- 
variance. Probability, then, is that which approaches but 
never reaches absolute invariance. In the example given 
above, of the gavel approaching the table, it was shown 
that as the time-interval decreased to zero, the proba- 
bility of the gavel striking the table grew greater and 
greater, until as the time-interval reached zero, proba- 
bility reached i, which is the symbol of certainty. 
Thus certainty cannot be predicted since the time- 
interval must be zero. Invariance, as we have shown, is a 
logical affair which applied to any actual occurrence is 
applied conditionally, i.e. if A then JB. Thus we can 
speak of the future only in terms of probability, and 



CAUSALITY AND PROBABILITY 179 

this probability increases as the future becomes less 
remote. 

If, then, probability is the asymptotic approach to 
certainty, certainty is involved in probability. It is pre- 
dicated as the goal, or else probability would have no 
definition. Who would attempt to predict the proba- 
bility of what John Smith is going to think about next 
Tuesday morning at ten o'clock from the knowledge of 
what he has thought about on past Tuesdays at ten, 
unless there were some logical connection between that 
hour on Tuesdays and John Smith's thoughts ? Without 
the assumption of some logical connection, known or 
unknown, no one would make a prediction of proba- 
bility. When the average period of gestation of a human 
being is said to be 279 days, this means that any baby 
probably will be born at the end of this period, though 
there is no absolute certainty and indeed wide variation. 
Surely such a probability takes for granted that there is 
some invariant connection between the gestation in- 
terval and birth, which is modified by many incidental 
factors in any given case. The statement that it will 
probably rain some time next month would make no 
sense if rainfall were purely a random affair. What gives 
it meaning is the fact that certain complex factors com- 
bine to yield the event wherever undisturbed by still 
others which are just as causal. Thus causality is always 
implied in any meaningful predication of probability. 

The history of scientific inquiry reveals the fact that 
causal laws were discovered through the finding of 
certain behaviouristic patterns where it was probable 
that certain events could continue to manifest invariance. 



i8o WHAT SCIENCE REALLY MEANS 

Any of the discovered laws of causality might have been 
formulated by means of probability, i.e. statistically. And 
so they would have remained, unless science had gone 
deeper to isolate necessary cause. If, ignoring such 
questions as air resistance, the law of falling bodies had 
been formulated statistically, i.e. from a compilation of 
many actual instances of various kinds of falling bodies, 
it would have taken this form: it is probable that any 
object falls at the rate of thirty-two feet per second per 
second. But instead of this, Galileo made but few ex- 
periments not enough for a law of probability and 
leaped to the conclusion that this acceleration was in- 
volved in every instance of every falling body, thus 
showing special cases to be modifications of die principle, 
because of calculable interfering factors. 

The rash overthrow of causality, where laws of proba- 
bility take their place, is based on the assumption that 
no causality is involved in probability. This we have 
shown to be an utterly indefensible assumption wherever 
statistics are expected to have any relevance to the future. 
Inasmuch as the laws of probability are relied upon by 
modern physicists, they are being used as quasi-causal 
laws, relied upon for their dependability and not for 
their undependability. They involve causality, whether 
that causality be known or unknown. And where it is 
unknown, they are interim laws, which will be discarded 
as soon as and if causal laws are found. Thus the attempt 
to predicate statistical laws as final is the same treason 
to the progress of science as the refusal to admit as 
possibly existent anything not already demonstrated. 
Both refusals are involved in the platform of positivism. 



CAUSALITY AND PROBABILITY 181 

THE STATISTICAL METHOD AND CAUSALITY 

Having shown that probability requires causality, we 
must now more specifically show that the statistical laws 
are another way of presenting causal laws. It will be 
remembered that causal laws are so framed as possibilities 
that when put into application they must always be 
modified by all the incidental factors which are not ex- 
cluded. A controlled experiment is an attempt to exclude 
as far as possible all such incidental factors. This cause 
corresponds to dominating function, modified in actuality 
by incidental factors. Causal laws merely state the domi- 
nating factors and purposely omit the questions of 
incidental factors. 

In the statistical method no attempt is made to state 
a priori what the cause or dominating function is. A 
function is chosen, and incidental factors slowly elimi- 
nated in favour of it. Given a certain function to examine 
in its actual operation, experiments are conducted which 
will give results tabulated in reference to this function. 
The function is understood throughout not as an abstract 
legal affair but as a prevailing tendency, which the 
experiment is supposed to reveal by averages. In such a 
situation, where it is impossible to eliminate many of the 
incidental factors, it is clear that the dominating function 
will be modified in a number of ways, varying according 
to the presence and interplay of the incidental factors. 
But it is also clear that the dominating function will, 
given a sufficient iteration, show itself, whatever it be 
called, cause or probability. What is being done when an 
average is struck of these iterations is the ruling out of 



1 82 WHAT SCIENCE REALLY MEANS 

incidental factors. In this case they are being ruled out 
not by abstraction deliberately planned, but by showing 
that in the long run of instances they do not really count. 
Thus cause or dominating function is obtained by experi- 
mental selective abstraction. A cause is shown to be at 
work. 

We are not denying that the statistical method has 
great usefulness. Its usefulness is apparent from what we 
have said above : in any situation where through ignorance 
or pure difficulty of manipulation it is impossible to 
isolate cause, the statistical method is helpful. This is the 
case of thermodynamics and quantum mechanics. It has 
been found practical in thermodynamics because it is 
impossible to follow the path of the individual molecule. 
It has been found practical in quantum mechanics, the 
study of sub-atomic entities, because not only is it im- 
possible to study the path of these entities, but even their 
continued identity is questionable. 

In practical affairs, for instance in the life insurance 
business, the statistical method has been useful, because 
it is impossible for a life insurance company to calculate 
the tremendously complicated and fantastically modified 
causes of death. If all the factors affecting the life of every 
individual could be known and traced at any given 
moment, the exact risk would be ascertainable. But as 
it is, the life insurance company can group all these 
causes into a gross probability. And in so doing they 
depend upon the uniformity of natural occurrences, and 
risk only the possibility that these causes will be greatly 
modified. Thus they depend upon causality for their 
solvency, and go bankrupt in so far as they depend upon 



CAUSALITY AND PROBABILITY 183 

the random element in nature. All planned human actions 
depend upon the regularity of occurrences and not upon 
accidents. 

It must be noted that the dominating function exposed 
by the statistical method approaches but never reaches 
certainty, only a high probability. Put in another way, 
it requires an infinite repetition to reach certainty. This 
is to say that to exhaust all the modifying factors of the 
actual environment absolutely, an infinite iteration of 
the experiment would be required. No actual element is 
ever absolutely isolated from the environment, which is 
another way of saying that no causal principle can ever 
be exactly fulfilled in any event. But an infinite number 
of such events must prove equivalent to the absolute 
causal principle. 

Perhaps an example will make this question of infinity 
clear. In the throwing of a pair of dice we know that 
ideally 12 will come up once in every thirty-six throws, 
since there are thirty-six combinations of all numbers 
and one combination of 12. This is figuring the situation 
abstractly. What happens if it is tried out experimentally ? 
In a limited number of throws, say two hundred, this 
situation will most probably not be borne out. But given 
a very high number of throws, say io 6 , the ideal relation 
will be very closely approached. Increase this number of 
throws indefinitely, and the results will bear out closer 
and closer to the ideal. But only an infinite number of 
throws can be expected absolutely to correspond to the 
ideal of ^g-. We need no experiment in this case to 
discover what the dominating function is, since die 
relation of one combination to all combinations can 



1 84 WHAT SCIENCE REALLY MEANS 

be calculated in a minute by means of arithmetic. 
But in the case of many occurrences this is not always 
possible. 

What, then, does such an ideal statement mean that 
when a pair of dice is thrown, 12 will come up once in 
thirty-six times? It means that the dominating function 
or cause in the situation is this arithmetical relation. 
When put into application, it means that an incalculable 
number of incidental factors are influential but that none 
is invariant. 

Causal laws are independent of actuality. But when 
applied the dominating function or cause is always 
operative in an actual situation as its invariant. But this 
function or cause does not show itself as invariant 
because the situation is modified by all the incidental 
factors, which, if completely taken into account, would 
finally have to exhaust the universe. Thus according to 
the uniformity of nature, strict causality reigns, but does 
not candidly so appear since we do not know in any 
actual situation what all the causes of the so-called 
incidental factors are. Thus the best that can be done is 
to find the necessary element, and to consider all others 
as unnecessary or 'chance.' To demonstrate the complete 
causality of every actual thing, we should have to under- 
stand the infinite interrelations of the entire universe. In 
statistical probability we reach an approximation to the 
cause of any situation, but cannot reach it absolutely 
without infinite repetition. In either case we see that in 
actuality no absolute prediction could be made without 
having on the one hand infinite knowledge, and on the 
other infinite time. The remote ideal of the causalistic 



CAUSALITY AND PROBABILITY 185 

method requires infinite knowledge; at any time the 
remote ideal of the statistical method requires infinite 
time. The results which the statistical method reaches 
by mathematical probability are just as causal and 
abstract as the results reached by the causal method. 
Both depend upon the logical invariance of functions; 
neither can be applied exactly to actual prediction, 
though both approximate it more or less closely. 

The whole attempt on the part of recent scientists and 
positivists of science to declare that causality is not a 
principle of nature, while admitting that probability is, 
constitutes a contradiction. It comes about through 
ignorance of two facts: (i) that causal laws never did 
attempt to predict actual occurrences absolutely, and 
(2) that probability requires for its very meaning the 
goal of certainty, or it has no definition. 

PROBABILITY AND LOGIC 

We have shown that causal laws are logical conditions, 
and are better understood as the more inclusive functions 
of less inclusive functions. With this understanding of the 
uniformity of nature as an unchanging hierarchy of 
functions, probability and the statistical method can be 
reduced to the logical up and down movements of an 
operator. In Chapter v we defined function as an in- 
variant relation between variables, which is an adequate 
definition so long as function is being viewed as present 
in actuality. But in the hierarchy of functions as we 
present it, the abstraction from actuality has been en- 
tirely accomplished, and function is then seen as having 



1 86 WHAT SCIENCE REALLY MEANS 

nothing to do with variables, but as being better definable 
as an invariant relation between invariant relations. Thus 
a function may be illustrated as one of the rungs in the 
ladder of the logical series, or perhaps better as one of 
the concentric circles. 

Any actual event, experiment, or demonstration must 
take place in terms of abstract functions. Any action is a 
particular consequence of the logical conditions, and may 
be viewed as a deduction from logical premises. Actions 
are implications of conditions. The freezing of water by 
an experimental method is an action; and as such it is 
compelled to conform to the uniformity of the nature 
of water, which freezes at zero Centigrade, under ordinary 
pressures. What, then, defines the freezing point of water 
is not the method by which it is frozen, but rather the 
law of its freezing, which determines whatever method 
is employed. This fact is the reverse of that assumed 
by Bridgman and the operationalists. A thing is not a 
thing because of the way in which it acts; rather it acts 
in a certain way because of its logical nature. A tiling is 
as it acts, not because it acts, but because it is. The neces- 
sity is a one-way affair from being to action and not 
from action to being. Action, which takes place in the 
temporal order, illustrates and does not constitute the 
conditions of action. Thus again we see that causality, 
which is reducible to function, is not a temporal affair, 
but is constantly being illustrated and exemplified 
mediately in time. 

Given this understanding of action and of the con- 
ditions from which action springs, we may illustrate the 
syllogistic nature of the statistical method. 



CAUSALITY AND PROBABILITY 187 

Perhaps the relation of i surface to 6 surfaces of a die is 

constant; 
Certainly these throws (a goodly number) are observed to 

approach constancy, 
Therefore it has not been disproved that constancy exists in 

this relation. 

Something like this is what is done in the experiments 
by which the statistical method is carried on. It will be 
noted that the result is a probable conclusion which 
occupies the same status as the conclusion from the 
syllogism on p. 150, illustrative of the experimental 
method from a causal hypothesis. 

In n experiments an average of -^ Jz was f un( i, 
Therefore it may be concluded that the abstract function 
involved in all instances is ^. 

This is a 'law of probability,' inductively discovered in 
the same manner as a causal law. There is no difference 
between them, inasmuch as causal laws do not claim 
absolute invariance in actual demonstration, whereas laws 
of probability seek in actual demonstration to approach 
as closely as possible to absolute invariance. Hypothesis, 
experiment, allowance, or disproof of hypothesis, 
abandonment, or correction of hypothesis this is the 
frank and classical method of discovering laws of 
causality. 

It is difficult to see where the statistical method of 
probability differs from this. Both conclude with 
abstract functions formulated as rigidly as possible. 
The fact that the statistical method ends with a 



1 88 WHAT SCIENCE REALLY MEANS 

mathematical formulation of function docs not dis- 
tinguish its results from those of causality. We have 
shown that cause properly understood is function, and 
that probability properly understood is cause, and there- 
fore also function. The statistical method is only a 
roundabout, but perfectly valid, way of following the 
causal method. 

Here, however, we reach an important caution. 
Statistical results must not be viewed as the final aim of 
a science. If they are so viewed, the progress of science 
is hindered and finally stopped. To consider laws of 
probability as the best that science can accomplish, is the 
same positivism which asserts that deduction is scientific 
but induction not, that science is empirical but not 
rational, that mechanism does not imply purpose and, 
finally, that the aim of science is directed toward appli- 
cation and practicality rather than toward abstract truth 
for its own sake. 

We have been demonstrating throughout that em- 
piricism is the direction down in the effort of discovering 
to what extent actuality is logical. There is no such thing 
as an empirical fact in itself, but a fact is empirical only 
in relation to a higher system. Such a higher system is 
itself an empirical fact from the point of view of a still 
higher system. In the light of this conception, causality 
and probability appear as one and the same, and the 
statistical method as both empirical and logical: em- 
pirical to the extent to which it refuses to leap to un- 
proved conclusions, logical to the extent to which it 
seeks to find abstract and invariant conditions of 
which actuality is only a set of illustrations often 



CAUSALITY AND PROBABILITY 189 

modified. Both causality and probability aid science 
in its mission of discovering the abstract hierarchy 
of logical functions, which is the condition of all 
natural existence in so far as reason is able to understand 
and control it. 



CHAPTER IX 
THE FUTURE OF SCIENTIFIC EMPIRICISM 

/ am come that they might have life: and that they 
might have it more abundantly. 

THE GOSPEL ACCORDING TO ST. JOHN 

SUMMARY OF THE ARGUMENT 

The revolution in physics has been the occasion for the 
return to philosophical speculation on the nature of 
science. This philosophical speculation has become 
divided into two positions: mentalism and positivism. 
Of the two, positivism, revamped and refined, threatens 
to become the orthodox philosophy of science. This 
preference for the positivistic philosophy is understand- 
able in view of the fact that it seems to fly the banner of 
empiricism itself. And empiricism is the indispensable 
bedrock of science, which it would be suicide to abandon. 
What has happened is that science, through its develop- 
ment, has unwillingly been forced toward a philosophical 
reconsideration of its own nature. In this reluctant 
effort, the charm of positivism has been that it seemed 
to necessitate the least amount of metaphysics and to 
possess the greatest appeal to hard stubborn facts. 

Undoubtedly scientists have been right in holding on 
to empiricism as the essential of scientific method. But 
empiricism does not involve positivism. Positivism denies 
the validity of the speculative reason. Empiricism rightly 
understood does not deny the speculative reason but 
rather requires it. Positivism is purely analytical, whereas 



THE FUTURE OF SCIENTIFIC EMPIRICISM 191 

empiricism requires both analysis and synthesis. Positivism 
is application, whereas empiricism requires both theory 
and application. Positivism would stop the advance of 
science, whereas empiricism requires continual advance. 
The proper understanding, then, of what science is 
depends upon the proper understanding of empiricism. 
Empiricism is a logical affair, and can be reduced to its 
syllogistic form. 

That empiricism, and a fortiori science, should have ever 
been considered an anti-rational affair, is only to be ex- 
plained in terms of its historical development. Experi- 
mentation was the watchword of those men who broke 
away from cloistered speculation and unexamined 
premises. In throwing over sacrosanct premises they 
believed that they were throwing over the whole of 
logic in favour of brute facts. Consequently the Renais- 
sance, which witnessed the birth of modern science, 
came to suppose that the empirical observation of fact 
and the speculative reason were opposed. The develop- 
ment of science necessarily drew these two threads to- 
gether in scientific procedure, but did not resolve the 
anti-intellectual bias of the scientists. Thus the procedure 
and the philosophy of science were, and still are, at 
variance. 

The preoccupation of scientists with experimentation 
led them to conclude that science is a description of 
actuality, and thus that actuality is an absolutely deter- 
mined affair. But the development of science, in the late 
nineteenth and twentieth centuries, toward more and 
more abstract and mathematical formulations, has made 
scientists realize that there was here no picturable cor- 



192 WHAT SCIENCE REALLY MEANS 

respondcnce between their formulations and the world 
of actuality. In short, the realm of physics represented 
nothing actual except mathematical symbols on paper. 
Such a realization has appealed to some interpreters as 
meaning that scientific formulations are inherently 
mental, having been formed in the mind and indicating 
the existence of a mind-stuff, of which actuality is but 
the appearance. As a check on this wild metaphysical 
'explanation,' the positivists have reformulated the older 
view into what is called operationalism and its similar 
theories, such as that of logical positivism, which asserts 
the concepts of science to be merely names for operations 
performed or performable. This denies objective reality 
to the objects of science, but does not evade subjectivism, 
as it attempts to do. It only states subjectivism bchaviour- 
istically, that is, it makes scientific concepts dependent 
upon the mind, and thus unintentionally destroys the 
basis of empiricism while endeavouring to save it. 

Science is neither "the compendious representation of 
the actual" (die history of actual occurrences) nor 
thoughts in the minds of scientists or of the race in 
general. The subject-matter of science turns out to be 
functions independent of consciousness and therefore 
non-mental; independent of actuality, and thus non- 
actual. Functions are the inexorable conditions of 
knowledge and actuality. The analysis of the scientific 
subject-matter shows it to be not the content of actuality 
but conditions abstracted from actuality, conditions 
which are purely formal. And thus science reaches and 
strives to make manifest an unchanging hierarchy of 
functions which is through and through logical. The 



THE FUTURE OF SCIENTIFIC EMPIRICISM 193 

whole success and direction of science illustrate that it is 
dealing with such a formal world, best represented by 
the least connotative symbols, i.e. those of mathematics. 
Science is the entire effort of man to acquire knowledge 
of this abstract world of independent real functions, 
which are the invariant conditions of existence. 

Given this independent subject-matter the abstract 
world of independent real functions induction and 
deduction may be seen as procedures ascending or de- 
scending, in short, as two directions of reasoning. 
Demonstration, as employed in scientific method, tests an 
induction by checking its deductive consequences against 
actuality. The test by consistency is the derivation of 
that induction from a more inclusive induction as a 
deductive conclusion. The first is merely allowance; the 
second is proof. It is to be noted that what is empirical 
is always the deductive direction down; and the status 
of items varies in accordance with the direction selected, 
so that what is empirical from one point of view is 
theoretical from another. 

The whole empirical proof may be understood, 
regardless of experiment or deduction, as the finding 
of what is involved in a system. Thus rationalistic and 
empirical fallacies may be seen as prohibitions against 
irrelevance, or the jumping from one system to another. 
When a higher system is dragged in to explain the con- 
stituents of a lower (the rationalistic fallacy), the results 
are contrary to economy or empiricism: that the simplest 
explanation must suffice. On the other hand, when the 
constituent parts of a system are employed by themselves 
as explanations of die system (the empirical fallacy), 



194 WHAT SCIENCE REALLY MEANS 

the result is too rigid an attempt at economy. Thus the 
fact that science works mechanistically (down) must not 
be construed to mean that there is no purpose (up), but 
only that science is concerned with analysing purpose 
into its mechanism. 

The vastly greater part of scientific attention is devoted 
to analysis. Induction may take five seconds; deduction 
twenty years. Induction is a flash, but deductive analysis 
and checking is a deliberate and often painstaking and 
long-drawn-out affair. Thus scientists are nearly always 
directed down, but can only be so because of a prior 
leap up. The method of science is down; the leading 
principle of science is up. 

In the light of the abstractive nature of scientific subject- 
matter, causality is seen not as a determinism of actuality, 
but as the principle of continuity, whereby the same 
function is present in different instances of actuality 
modified by accidental factors. Causality states the in- 
variance of a principle and not the invariance of its 
practice. Thus in application a causal principle can only 
be more or less unmodified, i.e. its absoluteness is more 
or less probable. The formulation of laws of probability 
does not deny causality but restates it in application. 
The statistical method examined shows itself to be a 
roundabout method of abstraction, ending in laws 
of causality abstract invariance stated mathematically. 
What are not invariant are their applications. Thus 
statistical probability does not in this regard differ from 
strict causal law. 

We have stressed scientific empiricism as the correct 
method and equated it with deduction, mechanism, and 



THE FUTURE OF SCIENTIFIC EMPIRICISM 195 

application. But these presuppose a logically prior 
direction: higher systems to analyse, theories to be made 
empirical, probabilities to be rendered invariant, pure 
science to be some day applied. All this may be sum- 
marized in the statement that science accepts no datum 
or system as final except pro tern., which means that the 
first postulate of science is the rationality of nature. 
Empiricism does not dispense with but requires the 
speculative reason. 

SCIENCE MUST BECOME SELF-AWARE 

The assumption is held in most scientific quarters that so 
long as science proceeds with the right method, it does 
not make any difference to the welfare of science whether 
scientists abstractly understand what their method is or 
not. Of course it must be admitted that physics has in 
the main kept to the correct scientific method. But the 
fact that it has done so is no warrant that it necessarily 
always will. How can it be expected to carry on for ever 
with a method which it does not abstractly understand ? 
Historically, the physical sciences stumbled upon the 
right procedure, misinterpreting causality as a locked 
determinism of actuality. This conception did well 
enough until further discovery showed it to be true 
only within narrow limits. Thus to-day the old presup- 
positions of a mechanistic world have proved inadequate, 
and science is left without a whole-hearted belief in the 
reality of its subject-matter. 

This eventuality has driven it to two errors : unbridled 
speculation and over-rigid empiricism. The first is repre- 
sented by wild and meaningless theorizing, the second 



196 WHAT SCIENCE REALLY MEANS 

by an over-emphasis on experimentation alone. But it is 
the latter direction in which the scientists arc tending. 
Either would kill the advance of physical science; the 
first by abandoning empiricism, the second by giving 
empiricism nothing to operate on. In the latter case, the 
presupposition that speculation is unscientific, and that 
the laws of science are nothing more than names for 
operations, may eventually destroy the very method of 
empiricism. The absurdity of considering every operation 
a disparate, unique and particular occurrence would 
render science nugatory by destroying all its attempts at 
unification. There would be nothing left but a catalogue 
of isolated experiments, a history of disconnected events. 
The positivism which poses as the true philosophy of 
science would hinder the future of physical science. But 
it has already prevented other studies from becoming 
sciences. Psychology, economics, sociology, and anthro- 
pology have all suffered. There being no correct abstract 
formulation of what scientific presuppositions and 
methods are, these social studies have endeavoured to 
follow what they conceived science to be, as exhibited 
by the physical sciences. The result is that they have 
swallowed positivism and ignored the implicit but 
correct method of physical science. In other words, they 
have already fallen into the same sterile procedure as 
we predict might happen to physics if it continue on a 
positivistic basis. The accumulation of uncorrelated data 
in social studies is already enormous, and indeed perhaps 
outweighs the data of the physical sciences. But this 
enormous accumulation has not been synthesized, and in 
fact now stands in the way of synthesis. 



THE FUTURE OF SCIENTIFIC EMPIRICISM 197 

Social studies have never reached the deductive stage, 
and indeed distrust deduction. This lack alone should 
indicate that here is no following of physics. The social 
studies are inductive, but they are inductive mainly at 
the level of common-sense observation, and thus have 
never attained any high abstractive level from which 
deductions could validly be made. The reason that they 
fight shy of such speculation is their false understanding 
of empiricism as precluding anything not observable at 
the level of common sense. Their kind of procedure 
might go on for ever, piling up generalized observations, 
without leading to one significant generalization which 
could throw light on new and unsuspected facts, and 
thus open up a fruitful field of inquiry. The most 
developed of the social studies are economics and psy- 
chology, which have to some extent looked for invariant 
and abstractive conditions. But even they have been 
hopelessly confused, and have failed to obtain anything 
solid enough for agreement, by their failure to understand 
the nature of scientific empiricism, which they per- 
sistently misread as a prohibition against the drawing of 
conclusions. 

The failure to understand explicitly what science is has 
not yet proved crucial to the physical sciences. But it 
may, and certainly will, if this condition is allowed to 
continue and science persists in its positivistic misinter- 
pretation. What is a danger to the physical sciences is 
already a disaster to the social sciences. The need for 
the abstract formulation of science is of the utmost 
importance to all science. 



198 WHAT SCIENCE REALLY MEANS 

RELATION BETWEEN SCIENCE AND SOCIETY 

So much for the correct understanding of science as it 
affects science itself. Science as an active institution, how- 
ever, is not an isolated affair. It is an integral part of 
society. Science is one social institution among many, and 
it demonstrably affects and is affected by all others. It 
cannot thus go on for ever in Olympian isolation, but 
requires integration with society as a whole. Therefore 
it can readily be seen that the correct understanding of 
science by society is of the utmost importance for science 
and for society. 

What does science require of society? Science requires 
that society support it and at the same time leave it 
free to develop as it sees best. What does society require 
of science? Society requires that science produce miracles 
in the shape of tangible results having practical applica- 
tion. So long as science furnishes these, it will be supported 
and lauded and left free. But if it should fail to rain 
benefits immediately understandable as such, there is 
always the danger that the public will become impatient 
of mere theory and withdraw its support. There is a 
paradox in all this, that if science deliberately sets about 
to produce practical results, it will not continue to pro- 
duce them. Practical results do not follow from previous 
practical results but are the by-products of development 
in speculative theory. Thus science is being most practical 
for society when it is considering practicality the least. 

The danger of the positivistic understanding of science 
on the part of non-scientists can be readily seen. Society 
will not wait patiently upon science but insists upon 



THE FUTURE OF SCIENTIFIC EMPIRICISM 199 

directing its course toward practical application. It does 
not want theory, it wants results; and will not give 
money for the benefit of abstract speculators, although it 
will give millions for laboratories. But of course without 
theory practicality is an impossibility. Unquestionably, 
if the pressure of popular positivism is exerted on the 
scientists, the results must be disastrous regardless of 
whether scientists themselves concur in such a philosophy. 

But if, on the contrary, society could form some 
understanding of what science is, of what it is engaged in 
doing, and of what it hopes to do, it would be realized 
that the greatest practicality to society lies in pure 
science. Society would cease its importunings for quick 
results. It would then be content to support science and 
leave it free to follow its own development. 

The relation between science and society involves far 
more than the question of whether science will be 
allowed to develop unimpeded. It involves the question 
of whether society will itself be allowed to develop. No 
one will dispute the great social benefits which are 
attributable to science. The whole stage of development 
of modern civilization can be laid directly or indirectly 
to the physical scientists. It is a platitude to assert that the 
modern standard of living depends upon technological 
proficiency; and modern technology, of course, is a by- 
product of the physical sciences. Its tremendous accelera- 
tion has paralleled the acceleration of physical science. 
There are also great benefits which have accrued from 
the biological sciences. The technology of medical prac- 
tice: hygiene, immunization, etc., are by-products of 
the biological sciences. It is not too much to assert that 



200 WHAT SCIENCE REALLY MEANS 

the whole superiority of the present day over the 
eighteenth century is almost entirely due to the progress 
of the physical and biological sciences. 

But meanwhile what has happened in the field of 
social relations? Have we any such improvement over 
the eighteenth century, or is there perhaps a retrogres- 
sion? It is rather the latter. The contradiction has 
developed in the last few decades that the greater the 
advance in technology, the greater the disaster in social 
life. Every time a labour-saving device is invented, and 
greater efficiency achieved, it means that more labourers 
starve, and thus a decrease in consumption follows an 
increase in productivity. 1 As another example of what 
happens when the sciences do not advance together and 
one science runs wild, we have technology producing 
equally 'beautiful work' in medicine and chemical war- 
fare. Without social science to guide technological 
chemistry, its applications may often cancel each other. 
Without social science to decide, we have only the 
vague normative judgment of good or bad, which is 
neither sufficient nor authoritative. 

This chaos in social relations has not been alleviated 
by the social sciences, in spite of their pretensions. In 
other words, social science has shown no such advance 
in understanding as has physical science. Now we must 
note that physical science was the occasion for the dis- 
location of social relations, as well as for the advance of 
technology. In fact, the advance in technology has occa- 

1 This is definitely true of capitalist society, but, logically speaking, 
need not be true of communist society, where a technological advance 
should result in an advance along the whole front of society. 



THE FUTURE OF SCIENTIFIC EMPIRICISM 201 

sioned the dislocation of social relations, in the absence 
of any exact knowledge or ability properly to organize 
them in accordance with technological advance. If this 
dislocation be permitted to go much further, the advance 
in physical science will destroy the organization of society 
which makes science possible. Thus by its very merit, 
physical science may cut its own throat. 

The question reduces to this. There is a race in progress 
between science and society. Will society understand 
science soon enough to allow science to develop a science 
of society by which both science and society can be 
saved ? 

The conclusion which develops from a consideration of 
the interrelation of science and society is that the de- 
velopment of every science is dependent upon the 
development of every other science. The rapid advance 
of any given science therefore forces the necessity for the 
rapid advance of every other science. Otherwise one 
science developing too rapidly will end by destroying 
society, and therefore put an end to its own development 
as well. It is one thing to have a leader, but quite another 
to have that leader so far ahead of the main body that 
he cannot any longer be followed. As a result, the army 
fails to hold the advance it had already made, and falls 
into chaos, whereas the leader is cut off from his support 
and perishes. 

Physical science has now forced the necessity for the 
development of social science, and this is imperative lest 
all science perish from contemporary society. If it be 
suspected that we are making wild and abstract pre- 
dictions based on pure speculation, and that there is no 



2oa WHAT SCIENCE REALLY MEANS 

observable immediate danger of any such eventuality, 
we have only to call attention to what is happening to- 
day in Germany, where an anti-liberal and reactionary 
social order gives no support and has no tolerance for 
anything not immediately useful to its narrow purposes. 
German society has failed to keep up with the standard 
set by German science, and has therefore discontinued 
German science. There is a deadly logic involved between 
the given stage of a social order and the given stage of 
science. Though some small leeway may be allowed, 
their ability to separate is definitely confined within 
certain limits. Therefore the understanding of science on 
the part of a society is requisite for both science and 
society. 

IS SOCIAL SCIENCE POSSIBLE? 

We have pointed the extreme snd urgent need for social 
science. Two objections will be made to this. The first 
will state that social science is already in process of 
development, and that it must be given enough time 
to become an adult science. The second will state that 
social studies can never become sciences on which to 
base predictions sufficient to guide society. Let us answer 
these objections. To the first we may reply that, as 
already indicated, a continuation of the present methods 
in social science will never yield an exact science because 
abstract and independent laws are not being sought, 
and will never be sought so long as social scientists mis- 
understand scientific empiricism. Social science is not a 
young science, but has been before the public as an 
organized affair nearly as long as chemistry. Moreover, 



THE FUTURE OF SCIENTIFIC EMPIRICISM 203 

during the time it has been promoted as a science, it has 
shown no signs of development. The development of a 
science is not a function of time but of the understanding 
of method. 

The second objection will require more consideration. 
There is a widespread conviction that a sharp break 
exists between the physical and the social sciences, and 
that the same method cannot prevail in both branches. 
This conviction has been given categorical authority in 
German philosophy, which distinguishes between natur- 
ivisscnschaften and geistesivissenschaften the mathematical 
natural sciences and the normative social sciences. What 
is implied, of course, is that exact mathematical measure- 
ment applicable to physical subject-matter has of neces- 
sity no applicability to social subject-matter. If this were 
true it would have to be granted that social relations could 
never be made the basis for an exact science, and therefore 
never broadly applicable to the guidance of society. 

The division between the subject-matter of physical 
science and the subject-matter of social science, naming 
the former empirical and the latter normative, assumes a 
fallacy which we have exposed above. 2 No subject- 
matter considered by itself can properly be labelled em- 
pirical or normative. It has been shown that the same 
subject-matter which is normative from one level is 
empirical from another, just as purpose analyses into 
mechanism and mechanism synthesizes into purpose. 
There is no a priori principle which forbids the treatment 
of values in social relations from being the subject- 
matter for empirical analysis, and from being analysed 

2 See p. 158 ff. for mechanism, and purpose. 



204 WHAT SCIENCE REALLY MEANS 

into their mechanisms, exactly as is done with the 
physical subject-matter. 

Value-judgments do not have to be regarded as un- 
analysable and as merely normative. For instance, 
biology might have taken the arbitrary position that the 
quality of livingncss is a value primitive and irreducible, 
and as such not subject to analysis or measurement. 
Certainly it is a value, but this docs not prevent biology 
from analysing this value into its mechanisms, without 
the need of introducing the value as an element in its 
analysis. Similarly, the analysis of the values involved in 
social relations must be for the uses of science wertfreiheit. 
Thus the fact that social relations are themselves values 
does not mean that as values they cannot be scientifically 
treated. They can be subjected to isolation, on which 
induction, deduction, and experimental verification are 
brought into play, until a sufficient deductive system is 
formulated which allows of mathematical treatment. 

We are unimpressed by the argument that social 
science is for ever precluded from the same procedure 
and therefore from the same measure of success that 
physical science enjoys. The proponents of this theory 
offer no argument in defence of their position. They 
seem to have taken the failure of social science and made 
it causal: because there has been no social science, there 
can be no social science. To erect a failure into a necessity 
is orthodox positivism. The door to science must be left 
open. That anything is more than likely to be discovered, 
is the true scientific attitude. Social science is a definite 
possibility. 



THE FUTURE OF SCIENTIFIC EMPIRICISM 205 
THE FUTURE OF APPLIED SCIENCE 

Science, like all rational endeavour, is directed toward the 
future. What has already been accomplished in its short 
past may be taken as the merest hint of what is to follow. 
Theoretical scientific formulations will be utilized for 
practical purposes in the future to a much greater extent 
than they are at present, even though such practicality is 
not at the moment envisaged. 

The future of applied science is not to be conceived 
merely in terms of great improvements along lines 
already laid down by present inventions. It does not 
mean only faster airplanes, better air-conditioning, 
lighter metals of greater tensile strength, etc. Nor must 
the advance of applied science be conceived narrowly in 
terms of mechanical technology and the saving of factory 
labour, although this is one of its services. The application 
of science must be understood more comprehensively in 
terms of the annihilation of the limitations of time and 
space, which is only another way of saying the saving of 
energy. What has formerly been conceived to be the 
'natural' and hence inevitable way of achieving material 
ends is shown by science to be a wasteful and often 
roundabout method. Many years ago no one would 
have dreamed that the production of agricultural pro- 
ducts could have been indefinitely improved and ac- 
celerated. They rather depended on 'nature.' But now, 
by the greater understanding of nature, its processes have 
been speeded up and made more efficient. For instance, 
the 'ageing* of spirituous liquors may be accomplished 
speedily. 'Napoleon' brandy, being a function of the 



206 WHAT SCIENCE REALLY MEANS 

action of enzymes and not of Napoleon, will be made 
overnight. It is not too much to predict that advance in 
biology will make the sowing of vast acres for a small 
yield unnecessary, and the same yield will be obtainable 
on a small patch controlled and not subjected to the 
accidents of weather. 

Since time immemorial, men have kept animals for 
their milk, meat, hides, and hair, and this has necessitated 
the slavery that goes with a parasitic existence. For the 
nomad practically lives like a parasite on cattle, and must 
therefore follow the cattle's way of life. But applied 
science, no less than theoretical science, abstracts to 
dominant functions. Technology poses the question of 
how much can be left out in the solution of any given 
practical problem. If we want only meat, hair, hides, and 
milk from cattle, why go to all the trouble of having 
to take care of herds? If we expect the action of 
enzymes, why wait on 'time' ? Why not merely manu- 
facture items where it is more economical ? Mr. George 
W. Gray points out 3 that given the wholesale manu- 
facture of the Lindbergh perfusion pump and, given the 
technique of keeping organs alive outside the organism 
in vitro perfected by Dr. Carrel, it requires no great 
imagination to suggest the picture of bovine mammary 
glands kept to perform their function udders without 
cows and such products as insulin produced by merely 
keeping part of the pancreatic gland rather than whole 
sheep to be butchered. 

But this is a timid and half-way presentation. Science 
abstracts from abstractions. And applied science will 
3 Harper's Magazine for February 1936. 



THE FUTURE OF SCIENTIFIC EMPIRICISM 207 

finally abstract from even the secretion of glands to the 
manufacture of the essential substances. Certainly milk 
and insulin will be synthesized in the laboratory without 
the useless cultivation of waste by-products. Moreover, 
technology need not copy the so-called natural product; 
it can make better milk and better insulin than the glands. 
What the practical results of a true social science would 
be staggers the imagination. If the world has wasted time 
and energy on material problems because of its ignorance 
of natural science, what was and still is its plight in 
wasted time and energy in social endeavour? Wars, 
revolutions, and social conflicts generally would be 
resolved by a proper social science. The hit-or-miss 
political blundering which goes on unaltered from 
ancient times would at last change into something 
rational and planned. This does not mean, of course, that 
at any stage of advance an effortless Utopia or a heaven- 
on-earth can be achieved. It does mean the resolution 
of those importunate problems which have held down 
human energy by demanding the most of it. This energy 
would be released not for a silly leisure of amusement 
and boredom but for the attacking of problems at a 
higher level. To paraphrase Plato, the purpose of applied 
science is not to create mere material riches (though these 
have their place) and the furtherance of life for its own 
sake, but to set men free for the pursuit of the good life. 

THE FUTURE OF THEORETICAL SCIENCE 

The marvels of applied science are not, however, the 
whole story of science nor even its leading purpose. 
Unfortunately, the public has no comprehension of 



208 WHAT SCIENCE REALLY MEANS 

science other than in its practical capacity. Thus, as H. G. 
Wells says, to most persons science is alchemy. The 
applications are the merest by-products of the great 
domain of science, which is once and for all concerned 
with the truth, and which must hew to that line and let 
the chips fall where they may. In this domain of science 
there are many yeomen who only stand and apply the 
technique, but the real advance of science is due to a few 
leaders who arc entirely occupied with carrying forward 
the theoretical aspects of science. 

The advance of science has been directed in the past 
toward greater specialization within sciences. Chemistry 
has split up, for instance, into physico- and bio-chemistry, 
biology into a score of special branches, each of which 
goes as a separate science. But the advanced science of 
physics begins to manifest another direction besides this 
one. The second movement is toward unification of 
branches previously considered disconnected. For in- 
stance, astronomy and physics have become one science, 
and the attempt is being made to discover a unified field 
theory which will subsume relativity and the quantum. 
The advance of science should move in these two 
directions: toward greater and greater analysis, and thus 
specialization, and toward greater and greater synthesis, 
and thus generalization. 

But the movement toward synthesis in the separate 
sciences is not enough. What is required is a synthesis 
which will be capable of embracing all the sciences 
already known and those to be known under one grand 
science. Such a general science of sciences would have to 
show each science as a special case of its universal laws, 



THE FUTURE OF SCIENTIFIC EMPIRICISM 209 

and thus exhibited the continuity between chemistry 
and biology, biology and psychology, psychology and 
sociology, etc. Its laws would have to be of a generality 
such that the laws of all separate sciences could be deduced 
as special cases, and yet not be superseded by the more 
general. 

With the development of science, a greater and greater 
rationality is required. But this does not mean a greater 
and greater mentality. In other words, men will not have 
to be born with greater cerebral capacity, either quanti- 
tative or qualitative. The advance of the race depends 
upon the discovery of ideas and not upon an advance in 
innate psychological capacity. A fairly stupid man, by 
using trigonometric tables, can accomplish what a great 
intellect would be unable to accomplish without them. 
We have shown that as a science advances it relies less 
and less upon flashes of genius and more and more upon 
a solid deductive background. Were it not for this fact, 
we might indeed look with dismay at the future of 
science, and a fortiori at the future of the human race. 
But with this understanding it may be seen that if all 
sciences advance together, their acceleration may increase 
indefinitely and this without a corresponding increase 
in innate mental capacity. The fact that each stage of 
scientific advance can start from the accumulated body 
of knowledge, and does not have to start from scratch, 
takes science out of the mentalistic psychological category, 
and even in the last analysis out of its reliance upon 
genius. 

We have already enunciated and subscribed to the 
principle of wertfreiheit, according to which science is 



210 WHAT SCIENCE REALLY MEANS 

free from values. But this does not mean that it does not 
start from values and emerge with them. It resolves 
values into rational equivalents, whereby newer values 
are allowed to be actualized. It is by virtue of the fact 
that science proceeds rationally and not affectively, that 
it is able to obtain new values. The achievement of values 
is not obtained through the envisagement of values but 
through scientific rationality which is value-free. 

The whole advance of reasoning may be said to have 
been this very reduction of that which was first normative 
to that which later became empirical. And thereby more 
and higher normative problems are perceived. The 
savage who sees the whole environment as normative 
friendly or unfriendly is not able to manipulate it, 
i.e. to increase its 'friendliness'; and thus he is precluded 
from envisaging higher values. To-day when we look 
to the good intentions of rulers rather than to scientific 
systems of government, and indignantly punish crimi- 
nality, we are in the plight of the savage: we have not 
reduced these normatives to empiricals. 

A similar reduction in the affective has taken place in 
some sciences: 'spirits' to 'properties' and 'properties' to 
pictorial entities, and finally pictorial entities to mathe- 
matical symbols. From the affective to the mathematical 
is the true direction of science. This is only another way 
of stating that the direction of all reasoning is from the 
normative to the empirical. 

The hope of the human race rests upon the develop- 
ment of science, which will discover for it values 
immediately useful and practical, and intrinsic values, 
to be appreciated far beyond anything that may have 



THE FUTURE OF SCIENTIFIC EMPIRICISM 211 

already been indicated. But hope and longing, and 
the attainment of immediate application, will not by 
themselves accomplish anything. All depends upon the 
understanding and allowed procedure of strict scientific 
empiricism. 



INDEX 



Aaron of Alexandria, 37 

Abel, F. A., 63 

Abstract functions, and actuality, 

186 
Abstractive levels, as formal and 

applied, 157 
Abstract systems, as resting on 

facts, 130 

Actual prediction, failure of, 174 
Adelard of Bath, 46 ; importance 

of, 43 

Aethicus, 41 

Agricola, 50 

Al-Battani, 38 

Albertus Magnus, 44 

Al-Biruni, as culmination of 
Moslem science, 39 

Alchemists, compared with chem- 
ists, 51 

Alcmaeon of Crotona, 27 

d'Alembert, 58 

Alexander of Tralles, 37 

Al-Farabi, 39 

Al-Farghani, 38 

Al-Fazari, 38 

Al-Hazan, 39 

Al-Kindi, 38 

Alphonsine Tables, 48 

Al-Quarizmi, 43 

Al-Razi, 38 

Al-Sufi, 39 

Al-Zarquali, 40 

Ampere, 61 

Analysis and synthesis, as direc- 
tions, 1 54 f. 

Analysis, not whole of science, 
103 f. 



Anaxagoras, 27 
Anaximander, 27 
Andalo di Negro, 47 
Anthemius, 36 
Apollonius of Perga, 32, 38 
Applied science, as application of 

pure, 156; future of, 205 
Apuleius, 41 
Aquinas, Thomas, 44 
Archimatthaeus, 42 
Archimedes, 38, 70; and principle 

of specific gravity, 32; quoted, 

31 

Aretaeus, 33 

Argument, summary of, 190 f. 
Aristarchus of Samos, 34, 48 
Aristotle, 28, 30, 36, 40, 46, 141; 

quoted, 29, 90 
Aristoxenus, 28 
Arrhenius, 62 

Astronomy, development of, 57 
Atomism, 158 
Avicenna, 40; as culmination of 

Moslem science, 39 
Avogadro, 62; Law, as scientific 

object, 107 

Babylonian science, 26 

Bacon, Francis, 72 

Bacon, Roger, 45, 46; importance 

of, 44 

von Baer, 63 
Balmer, 20; Law, 151 
Barrow, I., 55 
Bateson, W., 64 
Bauhin, C., 50 
Bayliss, 66 



214 



WHAT SCIENCE REALLY MEANS 



Becquerel, 62, 67 

Bcde, 41 

Bell, E. T., quoted, 143 

Bentham, 77 

Bergmann, E. von, 58 

Bernard, Claude, 63 

Bernoulli, 58 

Biology, failure to use mathe- 
matics, 56 

Biological development, difficul- 
ties of, 66 

Biological sciences, development 
of, 60 

Black Death, 46 

Black, Joseph, 60; phlogiston ex- 
periment of, 58 

Boethius, 41 

Bohr, N., 67 

Boltzmann, L., 62 

Borelli, G. A., 56 

Boyle, R., 54; and development 
of chemistry, 59 

Brahe, Tycho, 47, 50, 155 

Bridgman, P. W., 13, 17, 19, 81, 
1 86; quoted, 69, 91, 93 ff., 
169 

Brilliant insight, place of, 162 

Brock, Werner, quoted, 128 

Bruno, Giordano, 50, 53 

Buffon, G. L. L., 60 

Burtt, E. A., quoted, 49, 52 

Byzantine, and Moslem science, 
continuity of, 37; empire, 35; 
science, renaissance of, 37; 
scientists, kept science alive, 36 

'Can not' confused with 'has 

not,' 89 f 
Cantor, 63 
Capella, Martin, 36 



Carnap, R., 17; quoted, 86 fF. 

Carnot, Sadi, 62 

Carrel, Alexis, 206; quoted, 98, 
101 

Cassiodorus, 41 

Cauchy, A., 63 

Causal laws, and dominant func- 
tions, 184; in nature, 169 

Causality, as deduction from 
premises, 177; a principle of 
nature, 185; and invariance, 
194; confused with temporal 
sequence, 82; defended, 97; 
freedom from time of, 173 f; 
problem of, 168; retained in 
modern science, 170; wrongly 
defined, 174 

Cause and effect, as function, 73 ; 
confused with history, 64 

Cavalieri, B., 52 

Cavendish, H., 58 

Cayley, A., 63 

Celsus, 33 

Chemistry, and quantitative 
method, 58; development of, 
58 

Chloroplast, as function, 117 

Christian and renaissance empiri- 
cism, continuity of, 46 

Church, attitude towards science, 

49 

Circle, as function, 116 
City planning, first work on, 39 
Clausius, R., 62 
Clifford, W. K., 93 
Cohen, M. R., quoted, 75, 79, 151 
Comte, Auguste, 76 ff., 79, 86, 

90; influence of, 77 
Concepts, as functions, 113 
Condillac, 75 



INDEX 



215 



Condorcet, 75 
Constantinus Africanus, 42 
Continuity, and cause and effect, 

173; and causal laws, 71 f.; 

defined, 171 
Copernicus, 51; importance of, 

48 f. 

Coulomb, 58 

Criminality, as function, 118 
Curie, Pierre, 62 

Dagomari, 47 

Dalton, J., 59, 61 

Dampier-Whetham, 68; quoted, 
42, 54 

Darwin, Charles, 66; influence 
of, 64 

Deduction, and induction as com- 
plementary, 146; analysis of, 
147; in scientific method, 161; 
importance of, 163 

Definitions of science, confusion 
of, 13 

Demonstration, as empirical test 
of abstractions, 130 

Density, as function, 116 

Derivatives of abstractions, 129 

Desargues, 52 

Descartes, Renee, 52, 56 

Descriptive sciences, development 

of, 49 

Dicaearchus of Messina, 30 
Diderot, 75 
Dioscorides, 33 
Dirac, P. A. M., 68, 91, 93 
Dufay, G., 58 
Durand, D. B., 47 

Early Christian compendia, 41 
Economic man, as function, 117 



Economy, as check on wild 
speculation, 132 

Eddington, A. S., 17, 69, 83, 96, 
169; quoted, 84, 99, 103, 122 

Edessa, 37 

Egyptian science, 26 

Einstein, Albert, 67, 98, 132; 
quoted, 52, 97 

Empirical, compared with norma- 
tive, 203 ; dogmatism analysed, 
156, dogmatism defined, 155; 
entities, 14, 136, entities, differ 
in various sciences, 135, enti- 
ties, pass in and out of science, 
136, entities, recognition of 
true, 71; facts, as non-sensory, 
124; laws, 152 f, laws, in- 
validity of, 153; objects, as 
functions, 120; philosophy, 
bad effect on scientists of, 73 ; 
proof, direction of, 140, proof, 
involves system, 193; relation 
to logical, 145 ; science, failure 

of, 45 

Empiricism, absence of limits of, 
137; definitions of, 13; in- 
volves theory and fact, 71; 
levels of, 6 1 ; misunderstanding 
of, 69 f. ; not philosophical, 
14; and observation of actual- 
ity, 120; as principle of 
economy, 13 if; and the 
speculative reason, 144; as 
relative, I34f; as true scien- 
tific method, 190; two kinds 
of, 51 

Energy forms, interconnectivity 
of, 62 

English empiricism, as positivism, 



216 



WHAT SCIENCE REALLY MEANS 



Entities, 106; of science, 136 

Entity, and process compared, 1 14 

Erasistratus, 31 

Euclid, 32, 38, 42 f. 

Eudoxus of Cnidos, 28 

Euler, L., 58 

Euryphion of Cnidos, 28 

Eustachius, 49 

Events, as functions, 1 14 f. 

Exception, rejections of, 172 

Experience, analysis of, 122; as 
abstract, 125 f., and the given, 
123; and social agreement, 
124; bruteness of, 123 ; divorced 
from reason, 75 

'Experienceable* analysed, 92 

Experiment, as deduction, 153 f. 

Experimentation, as preoccupa- 
tion of scientists, 191 f.; no 
guide to true empiricism, 70 

Eymeric, 47 

Fabricius, 49 

Fact and reason, occasion for 
divorce of, 191 

Fallopius, 49 

Faraday, M., 61, 70 

Fermat, 52 

Ferminius, 47 

Fictions of science, as non- 
existent, 137 

Fitzgerald, 67, 132 

FlugelJ. C, 90 

Fourrier, J. B., 62 

Franklin, B., 58 

Fresnel, A., 62 

Frontinus, 33 

Function, as cause, 188; defined, 
in; as independent of vari- 
ables, 185 f. 



Functions, and the statistical 
method, 181; as abstractions 
from abstractions, 129; scien- 
tific implications of, 129 

de Fundis, John, 48 

Galen, 33 f., 49 

Galileo, 12, 47, 50, 52 ff., 55 f., 

70 f., 133, 172, 180 
Galvani, L., 58 
Gauss, C. F., 63 
Genetic biology, development of, 

6 5 f. 

Gerard of Toledo, 42 

Gerbart of Aurillac, 42 

Gesner, J. M., 50 

Ginzburg, B., quoted, 34 

Gray, George W., quoted, 206 

Greek, empiricism, early, 27; 
philosophy, stopped experi- 
mentation, 29; science, failure 
of, 28 

Greeks, interest in empiricism, 29 

Grey and Wheeler, 57 

Groot, 47 

Grosseteste, 43 f. 

Hamilton, Sir William, 13, 63, 

148 

Haphazard progress, danger of, 12 
Harvey, W., 49, 56 
Heidel, W. A., quoted, 26, 29 
Heisenberg, W., 68, 91, 93, 96, 

103 
Hellenistic science, too 'practical,' 

32; turned positivistic, 50 
von Helmholtz, H. L. F., 62, 90 

van Helmont, 54 
Henry of Hesse, 47 
Hermann of Dalmatia, 42 



INDEX 



217 



Hero, 33 
Herophilus, 31 
Herschel, J. and W., 57 
Hertz, 61 

Heuristic entities, 136 
Hipparchus, 33 
Hippocrates, 56 
Hippocratic Corpus, 28 
History, examined, 125 
Hooke, R., 56 
Hopkins, 66 
Hugh of Santalla, 42 
Hume, David, 73 f., 75 f., 82, 174 
Huygens, 55 
Hypatia, 36 

Hypothesis, in scientific method, 
159 

Ibn-Qurra, 38 

Ideal science of logic, as abstrac- 
tion from actuality, 142 

Idealism, defined, 17; objections 
to, 19 

Ideas, confused with thoughts, 81 

Impossibilities, later accomplished, 
90 

Indeterminacy, principle of, 97 

Induction, analysis of, 146; and 
deduction as complementary, 
146 

Irrelevance, meaning of, 148 

Isadore of Seville, 41 

Isolatable systems, the start of 
science, 104 

Jabir, 38 

Jacobi, 63 

Jeans, Sir J., 17, 69, 83 f. 

Jeffreys, Harold, quoted, 152 

John of Picardy, 47 



John of Saxony, 47 
Joule, J. P., 62 
Justinian, 37 

Kant, influence of, 76 
Keller, Helen, 127 
Kelvin, Lord, 62 
Kepler, 20, 5 of., 55 
Klein, Felix, 63 ; quoted, 143 
von Kleist, 58 

La Grange, 58 

Lamarck, 64 

Laplace, 57, 61 

Lavoisier, organizer of chemistry, 

59 ff- 

Law of action and reaction, 102; 
positivist view of, 102; men- 
talist view of, 102; realist view 
of, 102 

'Law of probability,' 187 

Laws, 106; as functions, 115 

Leeuwenhoek, 56 

Legendre, A. M., 63, 90 

Leibnitz, 53 

Lenzen, V. F., 169; quoted, 91 fF., 
170 

Leon of Thessalonica, 37 

Levi-Civita, 67 

Levy, H., quoted, 152 

Lindbergh, Charles A., 206 

Linnaeus, 60 

Lister, Win., 56 

Littre, 76 

Lobatchewsky, 63 

Locke, 72 

Logic, as empirical science, 141; 
becomes branch of psycho- 
logy, 78 ; utter reliance on, 87 



218 



WHAT SCIENCE REALLY MEANS 



Logical positivism, 86 fF., as em- 
pirical, 89; as incorrect pro- 
gramme, 91; as logical, 89 

Lorenz, H. A., 67, 132 

Macer, 41 

Mach, Ernst, 86, 92 f. ; father of 
positivism, 80; influence of, 
79; quoted, 79 f., 83 

Maclaurin, 58 

Magic in Middle Ages, 41 

Malpighi, 56 

Marcellus of Bordeaux, 41 

Marsupial, as function, 117 

Materialistic mechanism, diffi- 
culties of, 15; upset by rela- 
tivity, 17 

Mathematical model, substituted 
for mechanical, 68 

Mathematical science, method of, 

H3 

Mathematics, as empirical science, 
142; development of, 58, 62 

Maxwell, C., 61 

McKie, Douglas, quoted, 59 

Mechanical model, breakdown 
of, 83 

Mechanism, analysed, 158; and 
purpose, as mutually impli- 
cative, 160; and purpose, in 
scientific method, 161; and 
scientific method, 159 

Mendel, 64 

Mendeleef, 61 

Mcntalism, rejection of, 109 

Mentalist view, proponents of, 83 f. 

Merle, Wm., 47 

Meroe, 31 

Metaphysics, as empirical science, 
143 ; rejection of, 86 



Meyerson, Emile, 162 

Michelson, 67, 132 

Michelson-Morley experiment,67 

Microscopic physics, 67 

Mill, John Stuart, 77 ff. , 1 49 ; and in- 
ductive science, 78 ; quoted, 174 

Mind of God, as mathematical, 84 

Mind-stuff, 84; analysed, 108 

Minkowski, H., 67 

Modern chemistry, rise of, 54 

Modern physics, interpretive 
difficulties of, 69 

Morgan, T. H., 65 

Morley, 67, 132 

Moslem encyclopaedists and 
translators, 38 

Moslem science, becomes experi- 
mental, 38; decline of, 40 

Muller, J., quoted, 90 

Murphy, Gardner, quoted, 148 

de Murs, John, 47 

Musschenbrock, 58 

Mythologic entities, 136, 163 

Napier, J., 52 

Natural history, division into 

sciences of, 63 
Natural science, falsely divorced 

from social, 203 
Neckham, Alexander, 43 
Ncmorarius, 43 
Neo-pythagoreanism, 32 
Nestorian Christians, 37; in 

Ctesiphon and Baghdad, 37 
Neurath, 86 

New sciences, rise of, 62 
Newton, Sir Isaac, 12, 52 f., 71, 

103, I32f; and mathematical 

interpretation, 5 5 ; work of, 54 f. 
Nicholas of Cusa, 47 



INDEX 



219 



Non-empirical, as becoming em- 
pirical, 136 

Non-euclidean geometry, as ex- 
ample of high abstraction, 1 3 o f. 

Normative compared with em- 
pirical, 203 

Novara, 48 

Occam's Razor, 132 

Occult sciences, difficulties of, 132 

Ohm, 61 

Omar Khayyam, 40 

Operationalism, defined, 94; 

reputation of, 95 
Operationalist view, 91 f. 
Operationalists, and scientific 

functions, 119 
Oresme, Nicholas, 47 
Organizational levels, direction 

of, 138 

Organizational series, 138 
Onbasius, 36 
Origin of Species, 64 
Original science, beginnings of, 43 
Ostwald, W., 92 
Oxygen, discovery of, 59 

Pacioli, 48 
Palissy, 49 f. 
Parliamentarianism, as function, 

118 

Pascal, B., 52 

Pasteur, Louis, 66 ; influence of, 63 
Paul of Aegina, 37 
Pavlov, 1 6 
Pearson, Karl, 79; positivistic 

influence of, 82; quoted, 82 
Peirce, Charles Sanders, quoted, 

90, 146, 171 
Peter of Spain, 45 
Peter the Stranger, 45 



Petrarch, 47 

Petrocellus, 42 

Peurbach, 48 

Philip of Opus, 28 

Philiponus, 36 

Philo of Byzantium, 33 

Philosophical empiricism, not 

philosophy of science, 72 
Philosophy, empirical test of, 144 
Physical sciences, development 

of, 50 

Physicalism, 87; Cartesian, 56 
Physics, increasing objectivity of, 

68 

Pico della Mirandola, 49 
Picturable model, abandonment 

of, 69 
Planck, Max, 67 f, 103; quoted, 

68, 97 f, 168 
Planet, as function, 116 
Plato, 31, 35, 72, 107 
Plato of Tivoli, 42 
Pliny the Elder, 33 
Poincare, Henri, 63, 79, 93; as 

positivist, 80 f. ; quoted, 80 f. 
Poor investigators of science, 47 
Pope John XXI, 45 
Pope Paul III, 49 
Pope Sylvester II, 45 
Positivism, as danger to future of 
science, 196; as logical and 
empirical, 88 ; danger of, 190 f. ; 
defined, 18; denies reason, 
190 f. ; induced from science, 
57; objections to, 19; the 
preference of scientists, 18; 
spread of, 77 
Positivist view, proponents of, 

85 ff. 
Priestley, Joseph, 59 f., 129 



220 



WHAT SCIENCE REALLY MEANS 



Principles, application of, 174 

Probability, a principle of nature, 
185; as false substitute for 
causality, 178; defined, 178; 
examples of, 179, 183; in- 
volves causality, 180; involves 
certainty, 179 

Procedure and philosophy, danger 
of divergence of, 103 

Process and entity compared, 
114 

Processes, 106; as functions, 113 

Proclus, 36 

Profarius, 47 

Properties, 210 

'Protocol language,' 86 f. 

Ptolemaic system, 34 

Ptolemy, 33 f, 38, 48 

Pure science, as unapplied, 156 

Purpose, 158; analysed, 160; and 
mechanism, as mutually im- 
plicative, 160 

Pythagoras, and experiment on 
monochord, 27 

Quantum theory, 67 f. 

Rational dogmatism, analysed, 
156; defined, 155 

Rationality, independent of men- 
tality, 209; of scientific world, 
169 

Realist view, 96 rT. 

Reason, abandonment of, 76 

Regiomontanus, 48 

Reichenbach, H., 86 

Relativity, as example of true 
scientific method, 132 f.; 
general theory of, 67; special 
theory of, 67 



Relevance, as canon of causality, 

176; meaning of, 148 
Revolution in physics, as occasion 

for speculation, 190 
Reyjean, 54 
Riemann, 63 
Right-angled triangles, functions 

of, 112 

Robert of Chester, 42 
Roentgen, 62 
Roman Church, 12 
Rousseau, 76 
Rutherford, Lord, 59, 67 

St. Agobard, 41 

St. Aldhelm, 41 

St. John, quoted, 190 

St. Simon, 76 

Sarchel, Alfred, 43 

Sarton, G., quoted, 34, 40 

Scheele, 59 f. 

Schleiden, 63 

Schlick, M., 86; quoted, 88 

Schrodinger, E., quoted, 68 

Schwann, 63 

Science, abtsract nature of, 98; as 
necessity of interpretation, 16; 
as abstraction from experience, 
127; as abstraction of func- 
tions, 129; aim of, 1 88 f.; and 
increasing use of mathematics, 
68; and instinctive method, 
danger of, 195; and the 
modern world, 1 1 ; and philo- 
sophy, fatal separation of, 34; 
and the public, 23 ; and society, 
race between, 201; as know- 
ledge of external world, 98; 
as deductive system, 163; as 
hierarchy of functions, 164; 



INDEX 



221 



as hope of human race, 210 ; 
as observation of phenomena, 
78 ; as system of relations, 71 ; 
as wertfreiheit, 128 ; begins and 
ends with values, 210; directed 
toward application by society, 
198 f. ; directed toward future, 
205 ; distinguished from 
pseudo-science, 70; hierarchy 
of, I37f.; how it abstracts, 
128; ideal progress of, 164; 
ideal method of, i65f.; in 
twentieth century, rapid de- 
velopment of, 65; low state 
of, 46 ; not isolated affair, 198 ; 
necessity for public under- 
standing of, 22; nineteenth- 
century systematization of, 61 ; 
misunderstanding of, 207 f. ; 
more than method, 101; 
opposed to reason in seven- 
teenth century, 52; popular 
opinions of, 21; public faith 
in, 21 ; regarded by scientists 
as irrational, 75; requires 
metaphysics, 23; relation to 
society, 105; single grand, of 
future, 208 f. ; social require- 
ments of, 198; subject-matter 
of, 101 ; wrong understanding 
of, 192 f. 

Sciences, field of, 139; one way 
direction of, 140 

Scientific, academies, rise of, 53; 
advance, directions of, 208; 
developments, interdepen- 
dence of, 201; distinctions, 
undisturbed by similarities, 
108; endeavour, progress of, 
45; entities, not phenomena, 



no; empiricism, distinguished 
from common-sense empiri- 
cism, 135; inquiry, field of, 
102; laws, not mental sum- 
maries, 20; method, analysis 
of, 151, as application of logic, 
149; correct, 193, dependent 
on philosophy, 106, in mathe- 
matics, 152; objects, abstract 
nature of, 109 , as empirical, 
119, as functions, in, defined 
by functions, H2f., nature 
of, io6f, not actual, 109; 
progress, haphazard, 12; 
theory, as not affecting science, 
103; tradition, no break in, 35 

Scientists, anti-metaphysical bias 
of, 14; vague about science, n 

Scot, Michael, 42 

Scotus, Erigena, 41 

Self-consistency, as scientific re- 
quirement, 131 

Seneca, 33 

Servetus, 49 

Severus of Sebokht, 37 

Social relations, progress of, forced 
by science, 200 

Social science, argument for, 
202 f. ; confused with psy- 
chology, 65; failure of, 200; 
false divorced from natural, 
203 ; forced by physical, 201 f. ; 
possibility of, 204 

Social sciences, rise of, 64 

Social studies, predicament of, 
197 

Society, development of, depends 
on science, 199 

Socrates, 29 

Specialization, increase of, 61 



222 



WHAT SCIENCE REALLY MEANS 



Specific, distinguished from actual, 

72 

Speculation, judicious use of, 72 
Speculative vs. descriptive science, 

S3 

Spirits, 210 

Stallo, 93 

Starling, 66 

Statistical method, and certainty, 
183; syllogism of, 187; use- 
fulness of, 182 

Steno the Dane, 56 

Stephanus of Alexandria, 37 

Stephanus of Athens, 37 

Strabo, Walafrid, 33, 41 

Strato, 28 

Sydenham, 56 

Syene, 31 

Syllogism, logical, 150; of demon- 
stration, 150; of empirical 
laws, 153 

Sylvester, 63 

Synesius, Bishop of Ptolemais, 36 

Systems, hierarchy of, 147; in- 
clusiveness of, 171; infinality 
of, 172 

Swineshead, Richard, 47 

Technology, future development 
of, 206 f. ; ideal future of, 207 

Tensor calculus, 67 

Thales, 27 

Theophilus Protospatharius, 37 

Theophrastus of Lesbos, 30 

Theory and practice, thought 
opposed, 99 

Theory of science, as outside 
science, 99 

Thomson, 67 

Thorndike, L., quoted 41, 43 f. 



nor- 



Toscanelli, 48 
Transformation equation, 67 

Unification, increase of, 61 
Uniformity of nature, 1 171 
Universe, materialistic conception 
of, 64 f. 

Valence, as function, 117 
Value-judgments, as merely 

mative, 204 
Vesalius, 49 
Vienna Circle, 86 
da Vinci, Leonardo, 48 
Virchow, 63 
Vitalism, 158 
Vitruvius, 33 
Volta, 58 

Waismann, 86 

Walcher Prior of Malvern, 42 
Wallace, A. R., 52 
Watson, William, 58 
Watt, James, 59, 148 
Weber, Max, 128 
Wells, H. G., 208 
Weierstrass, 63 
Wertfreiheit, 204, 209 
Wheeler and Grey, 57 
Whitehead, A. N., 13 ; quoted, n 
William of Conches, 43 
William of St. Cloud, 45 
Wilson, 19 
Witelo, 43 

Wittgenstein, L., quoted, 86 
Wrong philosophy retards science, 
104 

Xenophanes of Colophon, 27 
Young, 62 



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