GESTALT
PSYCHOLOGY
BY
DR. WOLFGANG KÖHLER
NEW YORK
HORACE LIVERIGHT
1929
Copyright, 1929, by
Horace Liveright, Inc.
First printing, April, 1929
Second printing, April, 1929
Third printing, August, 1929
Fourth printing, October, 1929
PRINTED IN THE U. S. A. BY
QUINN & BODEN COMPANY. INC.
RAHWAY, N. J.
_To_
MAX WERTHEIMER
_Preface_
I OFFER this book to the patient reader, feeling more than ever how
much I have been inferior to my task. Nothing is easier than to
criticize it. _Gestalt_ psychology, the subject matter I have tried
to present, resembles in 1928 a promising start more than a complete
achievement. At all events it would have been difficult to introduce
it adequately. To present it skillfully in a foreign language was far
beyond my linguistic ability. I have done all that I possibly could.
The greatest difficulty, however, is that only certain simple and
almost crude concepts of _gestalt_ psychology would yield to my painful
efforts to convey them through the medium of English. Under these
circumstances the optimism of my excellent publisher is responsible if
the incomplete portrait of an incomplete thing is here recommended to
public consideration.
Certain other trends in contemporary psychology are discussed in
connection with _gestalt_ psychology. The first question a foreign
psychologist has to answer in America is, of course: How do you like
behaviorism? This vigorous school has energetically drawn certain lines
beyond which a psychologist should never go. And, then, indicating the
only direction that all psychologists must take, it has left little
place open for free discussion of theory and research; in other words,
it has developed into such a fundamentalism that I felt myself forced
to clear my way for a certain liberalism to which I am accustomed in
science.
With introspectionism things are not entirely different. In this
psychological school a scheme of procedure, which is just the
opposite to my own, has become dominant. This is unfortunate. If
behaviorists should refuse to take account of this book because in
it _direct experience_ is employed and referred to without apology,
introspectionists would not treat it any better, since my use of
experience, from their point of view, is not of the right sort. I have
had to explain, then, not only how I could eat the forbidden fruit in
spite of all commandments, but also why I took the common ware from the
street and from the market-place instead of buying the standardized
and sterilized products which introspection would furnish from its
cultivated orchard. It was my aim, however, to make this discussion
productive and, in addition to criticism, the reader will find some of
our own rules of procedure expressed in these first chapters. If the
fighting spirit should be found to prevail in some paragraphs, I beg
you to remember that, as in politics, we sometimes strike at a system
though we are fond of its defenders.
Certain psychologists, both in the United States and in England,
will recognize their own ideas or, at least, find some similarities
to them, in these chapters. Instead of treating all the instances of
this convergence and agreement in detail, I only mention the theory of
“emergent evolution” and the doctrine of Professor Whitehead’s imposing
work, with all the respect which is due them both. Perhaps Professor R.
M. Ogden will allow me to call him a _gestalt_ psychologist. I have not
been able to see quite clearly to what degree there is agreement with
certain other eminent psychologists. In Professor Bentley’s well-known
book, for example, his term “organization” sometimes seems to come very
near the concept of _gestalt_. But there must be some difference, since
on the other hand, the basic doctrine of introspective psychology seems
to be preserved in a manner incompatible with _gestalt_ psychology.
Future development will undoubtedly show whether or not our views can
be brought to a full congruence.
Dr. Mortimer Adler deserves the reader’s thanks as well as my own for
the skill and tact which he displayed in the correction of my text,
which was finally revised by K. Koffka.
My thanks are due to Mrs. L. Köhler, without whose help my work would
have been all but impossible.
To Max Wertheimer I should like to dedicate something of which I could
be prouder than these ten chapters. I hope he will accept them,
however, as a testimony of my good will and of our friendship.
W. K.
Ormor, Sweden,
August 12, 1928.
_Contents_
CHAPTER PAGE
PREFACE vii
I. THE VIEWPOINT OF BEHAVIORISM 3
II. PSYCHOLOGY AS A YOUNG SCIENCE 35
III. THE VIEWPOINT OF INTROSPECTION 70
IV. DYNAMICS AS OPPOSED TO MACHINE THEORY 103
V. SENSORY ORGANIZATION 148
VI. THE PROPERTIES OF ORGANIZED WHOLES 187
VII. BEHAVIOR 224
VIII. ASSOCIATION 269
IX. REPRODUCTION 301
X. INSIGHT 349
INDEX 395
GESTALT PSYCHOLOGY
I
_The Viewpoint of Behaviorism_
THERE seems to be a single starting point for psychology, exactly
as for all the other sciences: the world as I find it, naïvely and
uncritically. The naïveté may be lost as we proceed. Problems may be
found, which were completely hidden from our eyes at first, and for
their solution it may be necessary to devise concepts which seem to
have little contact with uncritical experience; nevertheless the whole
development should begin with a naïve picture of the world. This origin
is necessary because there is no other basis from which a science can
arise. In my case, which may be taken as representative of many others
essentially similar to it, that naïve picture consists, at this moment,
of a blue lake with dark forests around it, a big, gray stone, hard
and cool, which I have chosen as a chair, a paper on which I write,
a faint noise of the wind which hardly moves the trees, and a strong
odor characteristic of boats and fishing. But there is more in this
world: somehow I now behold, though it does not become fused with the
blue lake of the present, another lake of a milder blue, and I find
myself, some years ago, looking at it from its shore in Illinois. I am
perfectly accustomed to beholding thousands of pictures of this kind
which arise some way or other when I am alone. And there is still
more in this world: my hand and fingers moving lightly over the smooth
surface of the paper; now, when I stop writing and look around again,
there is a feeling of health and vigor, but in the next moment I feel
something like a dark pressure somewhere in my interior which tends to
develop into a feeling of being hunted--I have promised to have this
manuscript ready within a few months.
Most people live in such a world permanently, which is _the world_ for
them, and hardly ever find problems or difficulties in its properties.
Crowded streets may take the place of the lake, a cushion in a sedan
that of my stone, some serious words of a business transaction may be
remembered instead of Lake Michigan, and the dark pressure may have
to do with tax-paying instead of book-writing. All these are minor
differences so long as one takes the world at its face-value, as we all
do except in those hours when science disturbs our natural attitude.
There are problems, of course, even for the most uncritical citizen of
this first-hand world. But, for the most part, they do not refer to the
nature of it; they are of a practical or an emotional sort and they
usually mean that, this world being taken for granted, we do not know
how to judge or how to behave in that actual part of it which we face
as our present situation.
Various sciences, most of all physics and biology, began centuries
ago to destroy the simple confidence with which human beings take
that naïve world as _the reality_. Though hundreds of millions still
remain undisturbed, the scientist has found it, in some respects, full
of almost contradictory properties. Fortunately he has been able to
discover another world, as it were, behind it, whose properties, highly
different from those of the everyday world of naïve people, do not seem
to be contradictory at all. No wonder therefore that now, as psychology
begins to be a science, some of its most energetic students should wish
to make it go the way of the exact sciences at once. Indeed, if other
sciences have found the naïve world of everyday reality impervious to
and unavailable for scientific method, what hope of better success can
we as psychologists have? And if the enormous and almost impossible
feat of jumping out of the world of direct, but confused, experience
into a world of clear and hard reality, has already been achieved by
physical science, it would seem wise for the psychologist to take
advantage of that great event in the history of science and begin to
construct psychology on the solid basis laid down by the physicist and
the physiologist outside the field of uncritical experience.
A few words about the history of scientific criticism will help to
define better the material or field to be given up by psychological
investigation and to indicate what shall be taken as a better object
of research. Our naïve experience consists of objects, their properties
and changes, existing quite independently of us. It does not matter to
them and their existence whether or not we see and feel and hear them;
they remain exactly as they are when we state their properties, when
we are not present or are occupied in other matters. It was a great
step when men began to ask how seeing and feeling and hearing occur,
and it was a revolution when they found that colors and noises and
smells, etc., were merely products of some of the influences exerted
on man by his surroundings. Still these surroundings seemed to subsist
in their primary characteristics and to remain “the real world,” if
only you subtracted those “secondary qualities” as purely subjective
ingredients. But finally even the “primary qualities” of naïve realism
were assimilated to the secondary as subjective. The form, weight and
movement of the objects of immediate experience were treated as colors
and sounds, i.e., as functions of the experiencing organism, as end
results of its complicated processes. And therefore we cannot hold that
these objects excite the processes, since, according to this point of
view, their very existence as parts of immediate experience is only a
consequence of these processes. So the picture of the objective and
independent _physical world_ of physical things, of physical time,
of physical movement and physical space, has to be constructed as
something different from the world-picture of direct experience.
Physical objects, which _as such_ we can neither see nor feel, exert
upon each other a great variety of physical influences, which _as such_
similarly do not occur in the world of immediate experience. There is
one physical object more interesting than all the others but in every
way as foreign to naïve experience as they are: that is my physical
body, an astounding system of electromagnetic entities. If the right
influences be exerted upon this system by other physical objects,
those processes will occur in it, the consequences of which I know
as the exterior part of the world of naïve experience, the so-called
external sensory world. But an enormous amount of physical activity
is constantly going on inside my body. We have sufficient grounds,
therefore, to assume that there are still other processes with the
occurrence of which the _inner_ side of our immediate experience is
connected: such are the feeling of strain, when I contract the muscles
of my arm, also that of hunger and fatigue, my “memory image” of Lake
Michigan, fear and hope and so on, almost _ad infinitum_.
At present we shall not consider _how_ the physicist accomplishes the
gigantic task of investigating the properties of a world which does not
appear directly in any part of immediate experience. But there can be
no doubt concerning the remarkable success of his procedure. Whereas
the world of naïve man is somewhat confused, revealing its subjective
character in any critical discussion of its properties, the world of
the physicist gives short shrift to confusion and contradiction. And
though we find ourselves surprised by the rapid changes which physical
theory undergoes in our times, we still have the feeling that progress
is made with most of these changes. Eventually there will be agreement
about all the more important properties of the physical world.
For a while psychology was supposed to be the science of the events of
direct experience, both in its external and its internal aspects, as
contrasted to physical objects and occurrences.[1] By description of
direct experience the psychologist hoped to get not only an orderly
registration of all the possible varieties of such experience, but also
a great deal of information about the functional relations among these
events. He even aimed at formulating laws governing the flow of direct
experience.
The well-known psychological school of behaviorism has leveled
against the older psychology the criticism that it was misguided
both with respect to its subject-matter and its aim. It has not been
possible, according to the behaviorist, to register the varieties
of direct experience in a convincing manner, nor has anything come
of the attempt to describe their functional relationships or to
formulate the laws of so-called “mental life.” In no respect, the
behaviorist holds, do we have the impression that there exists a real
and progressive science of direct experience, clear in its methods
and results. On the contrary, we find endless discussions of minor
and, less frequently, major items, different psychologists giving
quite different descriptions of “facts” which are supposed to be more
or less the same for both of them. Take the example of “images”! One
psychologist claims to have them in numbers, many of them almost as
lively and concrete as perceptions. Others tell us that there are no
real images at all in direct experience and that probably the first
man was deceived by words or other motor phenomena which correspond to
objects and facts not actually present in experience. If the famous
method of “introspection,” i.e., observation of direct experience,[2]
cannot give better results in such a gross investigation, what shall
we expect from it when we are confronted by questions of equal or
even greater importance which are also more subtle and intrinsically
more difficult? Unfortunately, the adherents of introspection do not
seem to trust their own procedure. At least they must have agreed
upon facing important problems as seldom as possible, since they are
occupied mainly with describing the more remote and less exciting
corners of experience, as e.g., minor nuances of sensations, or the
“glassy” appearance of certain parts of space, and so forth. If all I
have to do to develop the science of direct experience is to describe
it, why then not attack the central facts of “mental life” at once,
instead of scratching a little at the surface, or periphery, of it?
There was a time in Germany, not very long ago, when people began to
joke about psychology’s ponderous discussion of trifles. And, indeed,
it was strange to see how the description of a direct experience, what
happens, for instance, during a single comparison of two tones or
colors, could fill hundreds of pages without giving us the slightest
positive idea about how the occurrence and accuracy of such a
comparison might be explained. Even in a state of perplexity a science
can be highly interesting. But psychology, so far as it deals with
direct experience by the method of introspection, has not only been a
complete failure; it has also become boresome for all those who are not
professionally connected with it.
And the behaviorist is not slow in giving us reasons why this must
be so. The meaning of “direct experience,” through opposition to the
world of physics, becomes associated with concepts like “the mental,”
“mind” and “soul,” almost without our being aware of this association.
Thus gradually this term becomes the expression for “spiritual life”
or the name for the effects of a special mental substance, existing
independently of the facts of physics and biology. Consequently, all
the old prejudices and superstitions of religious or metaphysical
extraction slip into the concept and into the treatment of direct
experience. The psychologist loses his impartial judgment; what he has
heard about “mind,” or “soul,” and their miraculous properties since
the early days of his childhood, creeps into his statements and makes
“introspection” an ill disguised rhetoric in favor of prescientific
mythology and medieval darkness.
However, if this were the only argument against introspection, the
introspectionist might answer that if the behaviorist were right in
this point, his criticism would not apply to the description of direct
experience itself, but rather would indicate an accidental source of
defect in the method. Then, some increase of self-criticism and a
careful elimination of religious or metaphysical interests in students
of psychology might be a remedy for these defects, and a very welcome
gesture towards sober behaviorism at the same time.
But the behaviorist has other reasons for not accepting direct
experience as a field of scientific research. First of all, as a
procedure, introspection lacks the chief methodological virtue of
physical research, a position of observation external to the system
under observation; on the contrary, it is a special process _in_ this
system itself, and all chances are against its leaving the “observed”
parts of the system undisturbed. _Hinc illæ lacrimæ!_ An example of
this is the attempt to study introspectively the direct experience
of sorrow and joy; they do not remain the same, but rather tend to
disappear when the selfsame person who has or had the sorrow and the
joy must assume the attitude of introspection.
But even supposing that this difficulty might be overcome by some
scarcely imaginable improvement of the method, we still should
find it useless, the behaviorist argues, because of its miserable
and inevitable subjectivity. What is the first characteristic of
an objective statement as the result of an objective scientific
procedure? That whoever happens to be interested in it can be obliged
to understand it in one determinate meaning, if only you give him exact
definitions of the terms you are using in your statement. So we define
the atomic weight or the atomic number of an element, so analogy and
homology of morphological structures, and there is no physicist or
biologist who does not know the exact significance of those words.
If now you listen to psychologists talking, let us say, about the
“confusion” which they observe in peripheral vision, what exact meaning
can be conveyed by this word so long as it is not fixed by definition?
A real definition, however, seems to be impossible wherever one has to
do with the ultimate data of direct experience. If you are asked for
the definition of “confusion,” you may attempt to define it negatively,
say in terms of “lack of clearness.” But that does not help you very
much, since your friend will then ask what you mean by “clearness.”
You may tell him that a rather high degree of clearness is a normal
property of the central parts of a simple and orderly visual field. But
such a field might have more than one normal property and you did not
give a _differentia specifica_ in your pseudo definition, in addition
to which the words “simple” and “orderly” need definition as badly as
did “confusion” and “clearness.” In any case, you have now resorted
to the only thing which seems feasible where, as in this field of
direct experience, a true definition cannot be achieved, viz., a kind
of _demonstration_. You do not define your term, but you give your
friend a hint about what conditions are necessary in order to have
the specific kind of direct experience about which you are talking.
Supposing that he understands the words by which you describe those
conditions, there is some chance now that he may attach your undefined
term to the precise phase of his actual direct experience that your use
of the term intended. But what a crude and altogether vague procedure
this is, if you compare it with the elegant definitions of the exact
sciences!
And still we have supposed that, given the same conditions, your
friend, who cannot make statements about any direct experience
except _his own_, must find in it the same properties, objects and
occurrences, which you have found in _your_ direct experience. You
cannot, as the physicists seem to do, make your two statements about
one and the same event, neither do you make readings from one and the
same apparatus or scale. You have _two_ events in _two_ experiences.
What is your evidence for assuming that under the same conditions the
ultimate data of experience are the same for both of you? Unfortunately
you shall never know whether this is the case or not. On one hand,
color blindness and similar phenomena show conclusively that such
an identity does not exist; on the other, you have no proof of that
identity even in those cases where all the tests you might imagine
give the same description, i.e., the verbal report you both make. Your
friend may report “red” where you say “red.” Still you do not know
more than that your friend always has the _same_ quality wherever and
whenever you have your “red,” without knowing at all that he has _just
that_ quality which you call “red.” Neither does it help you to a real
identification of qualities in the two direct experiences that what he
calls “red” seems to have (more or less) the same “stimulating” value
as you find verified in your own description, because you will see at
once that he may use the same term “stimulating” in quite a different
meaning, so that he does not have the same kind of experience when he
uses it.
This is subjectivity in its extreme form. If every one has his own
direct experience and if he is forever excluded from that of all other
persons, direct experience is the private affair of each of us, and
with respect to it a common science cannot possibly be achieved.
Indeed, so little can be derived from the direct experience of one man,
concerning similar experiences in others, that, in epistemology, it has
become a truism that I shall never know whether or not there exists
any “direct experience” at all even in my best friend. Whatever I see
or hear when we talk together is a part of _my_ experience. Certainly,
what I call his attitude, or his voice, in my experience, is determined
by physical events in the muscles and in the nervous system, etc.,
of his physical body. It is not only possible but even necessary to
understand these physical events from the viewpoint of pure physics
or physiology. Consequently, there is no proof that some of these
processes in my friend are accompanied by “direct experience” in him.
The behaviorist might add to this criticism that he does not deny
the great contributions which, before his time, the older forms of
psychology have made to the advancement of this science. But he will
say that, looking upon those achievements from the present point of
view, one will easily discover a simple fact: viz., that nearly all of
them are to the credit not of introspection and description but of the
“objective experiment.” The meaning of this word may be explained as
follows: Instead of making a subject observe and describe his direct
experience in a given case, we place him in a well-defined situation
to which he has to react by certain performances. These we can state
and measure without his giving us any description of his experience.
So Weber’s law was discovered; this was the kind of experiment by
which Fechner made psychology an experimental science; memory and the
formation of habits were investigated by research of this type with
almost no introspection; and since Binet and Simon we have learned to
treat intelligence in the same manner. If we are not mistaken, even the
introspectionist gives us “descriptions” of colors and tones, pleasure
and volition, only so long as he has not found a method by which he
might transform them through objective experiments into measurable
achievements or reactions. The introspectionist himself seems to accept
the “descriptive” observation of a fellow introspectionist, according
to the measure in which the other has been able to give objective
experiments as a verification and corroboration of his descriptions.
What, then, is the use of “direct experience” and its description?
From their common criticism all behaviorists do not draw quite the
same conclusions about “direct experience.” None of them, it is true,
find direct experience a matter of interest for science, since as the
private affair of those who have such experience it is not accessible
to the objective observation undertaken by others, as it ought to
be were it a proper object of scientific research. A few members
of the school seem to go so far as to deny the existence of direct
experience altogether; they simply abominate the notion. But these
minor differences of opinion are of no importance for us, because
in the question of _method_ all behaviorists have not only the same
negative but also the same positive opinion. Their program is a simple
consequence of the foregoing argument. In his objective experiment the
psychologist has tacitly accepted the procedure of the exact sciences,
even if he has not become fully aware of the difference in principle
which separates this attitude from that of introspection. Both the
physicist and the chemist are interested in knowing how a system
which they are investigating will react when exposed to a certain
set of conditions; they also ask how the reaction will change with a
variation of those conditions. Both questions are answered by objective
observation, registration and measurement. This is exactly the form of
real experimentation in psychology, too: a subject of a certain type
(child, adult, man, woman, animal) is the system to be investigated;
certain conditions are given and objectively controlled; the most
important of these we call “the stimuli”; and a reaction occurs which
is observed quite objectively.
The only thing which psychologists need, then, is to recognize,
generally and in principle, that this form of procedure is the only
possible one, and also that it is precisely the same as that of all
other exact sciences. Behavior, i.e., the reaction of a living system,
is its only subject-matter, and behavior in no way includes any direct
experience. In the experimental work of the future, even the highest
forms of behavior will be studied and described in purely objective
terms. They _must_ be, since personal, direct experience does not occur
at a single point in the whole experiment. For some this truth is
somewhat hidden by the fact that in most of our experiments language
reactions are of a special importance. If the experimenter himself
enjoys what he calls direct experience and if this experience includes
a great many things associated with words, he will be inclined to
take the words of his subject as signs of similar direct experience
on his part. Nevertheless, the words are registered as responses
of the subject, and as such are purely objective, physical facts,
produced by certain processes in the larynx and the mouth of the
subject. Though the experimenter knows that other objective processes
(of innervation, inhibition, and so forth) will have occurred before
these sound waves are produced by the action of muscles, he will
never be able to decide, according to our analysis, whether there was
any direct experience accompanying those inner processes. Perhaps
we should discipline ourselves to a less frequent use of language
reactions in our experiments, until finally we overcome the danger of
associating language with direct experience, and introspection will
have disappeared from psychology as an exact science.
Of course, not all the reactions of the subject are observed with
equal facility in the objective manner. Sometimes even strong
stimulation will not produce any overt behavior which can be registered
externally with our present methods. But in the majority of these cases
the physiologist can give us highly valuable information about the
functioning of the autonomic part of the nervous system and about the
subsequent reactions which occur in the most important visceral organs,
including the endocrine glands. One of the main tasks of psychology
will be to develop and to adapt the physiological techniques until
these visceral reactions can be registered with perfect ease under the
conditions of behavioristic experimentation. We also have some evidence
for assuming that, in addition to the reactions just mentioned,
so-called “thinking” consists in slight innervations of the muscles
concerned in speech reactions.
* * * * *
So far I hope that I have given a fair statement of the opinions which
prevail among behaviorists. It ought to be the more correct, since I
sympathize with these opinions in several points, most of all in the
criticism of “introspection.” Indeed, much of current introspection
seems to be rather sterile and, in an odd contrast to its ambitions,
to lead research away from the more urgent problems. Whether this be
an intrinsic property of introspection or merely a consequence of some
accidental mistake usually associated with it, we shall discuss later
on.
At present, we have a simpler problem before us. In the natural
sciences, so the behaviorist tells us, methods deal with objective
reality, whereas in the treatment of direct experience--if there
is such a thing--they deal with something entirely subjective. Is
that true? Is that the real reason why natural science has won the
admiration of the world and psychology is still in an embryonic state?
I cannot admit it. It seems to me that, starting with an admirable
enthusiasm for exactness, behaviorism has been misled completely at
this point and that, consequently, the energy spent by behaviorism in
its fight against “direct experience” and “consciousness” has been
spent in the wrong direction. So, at least, the situation appears to me
because, whatever may have happened to the keen leaders of behaviorism
in their individual development, I must give the following report about
myself. It is a well-known story, but some psychologists seem to have
forgotten it.
There cannot be the slightest doubt for me that, as a child, I had
“direct experience” before I even dreamed of a world like that of
physics. Of course, I did not know that term then, which could acquire
its meaning later on only by the very fact that the world of physics
became opposed to it. There were innumerable varieties of experiences
appearing as “objective,” i.e., as existing or occurring independently
and externally. There were other experiences which belonged to me
personally and privately, and insofar were “subjective,” such
as, among others, dreadful fear upon certain occasions, and an
overwhelming, warm happiness at Christmas.
In the following chapters we shall be occupied mainly with “objective
experience.” This term, however, may be misinterpreted rather easily.
So I shall try to specify its meaning a little more. Doing so, I shall
even run the risk of repeating some arguments several times, because
this is the point where most of our difficulties arise.
The name “experience” seems to indicate that, though appearing as
“objective,” those things and events were felt by me as “being given in
my perception” and therefore as “subjective.” Certainly, they were not.
They simply _were there outside_, and at that time I had no suspicion
whatever of their being the effects of something else upon “me.” I
must go further. There was not even a question of their depending upon
my presence; upon my keeping my eyes open, and so forth. When I went
around an object it remained the same identical thing. So absolutely
“objective” were those objects and events, that there was no place left
for a more objective world. Even now, this “objectivity” is still so
strong and natural, that I am constantly tempted to attribute to the
interior of these self-same “things” all those properties which, in the
meantime, physics has taught me to attribute to objects of the physical
world. When, in these pages, I talk about “direct experience” of
the “objective” type, the word is always used in this meaning: e.g.,
a chair as something there outside, hard, stable, brown, generally
without any taint of “being perceived” by me, of being “a subjective
phenomenon.”
In some cases, it is true, the discrimination between the
“objective” and the “subjective” side of direct experience may
become dubious: as with after-images or with the prick of a needle
in my finger. That does not make the discrimination less important
in itself. In physics the discrimination of the conducting
substances from insulators remains of high value, though between
the extremes we find a great many intermediate cases. For us, the
main point is the fact that in “things” and their “movements,”
etc., an almost unsurpassable degree of “objectivity” is reached.
At the time when I began to understand physics I did not learn only
about the physical world. Another lesson was necessarily connected with
studying physics, and it was this lesson that gave the term “direct
experience” its connotation or, better, which introduced me to a manner
of thinking that made the meaning of “direct experience” clear. The
physical world could not be the same as that “objective” world which
I had had around me the whole time. Certain physical objects were
found to influence a particularly interesting physical body, viz., my
physical organism, and what has been called “objective” experience
here, was shown to depend upon subsequent and very complicated
processes in that physical organism. Though that influence, exerted by
other physical objects, starts these processes in the organism, there
is no possibility of identifying the final product, “things” and their
“changes” as I have them in immediate experience, with those physical
objects from which the influences came. If a wound is not the gun which
emitted the projectile, then the “thing” which I have before me, which
I see and feel, cannot be identical with the corresponding physical
object. This object, influencing my physical organism, produces certain
disturbances in it, _the final outcome_ of which is the “thing” before
me in direct experience.[3]
Such “things,” however, were the first items _I knew_. Therefore, a
picture of the physical world had to be _constructed_ after I once
appreciated the necessity of it. Hence it is built up by inference as
something found indirectly or mediately; and, _in contrast to it_, the
world around me, as I had it before and still have it, quite apart from
the physicist’s construction, is now called the world of direct, or
immediate, experience.
But how can I say that a “chair,” for example, is an “objective
experience” if I must admit that it depends upon certain processes in
my organism? Does not the chair become “subjective” then? It does and
it does not. At this very moment the meaning of our terms has changed.
In the last paragraphs “objective” has denoted a certain experienced
property which some parts of my direct experience, in contrast to other
experiences, possess _as such_ (exactly as they have size, color,
hardness and so forth); the term “subjective” in _this_ paragraph means
their genetic dependence upon my physical organism. “Subjectivity,” in
this latter meaning, is not itself a directly experienced property,
but a relationship which we ascribe to “objective” experiences after
we have learnt to regard them as the outcome of organic processes
and, therefore, as distinct from the physical reality external to the
physical organism. Sometimes the two connotations of the term are
confused in the most deplorable manner as though what is “subjective”
genetically ought also to be “subjective” in experience. So most
introspectionists seem to think that, properly speaking, the chair
before me must be a subjective phenomenon _in experience_, appearing
“before me” only in consequence of some illusion. And since there is
no “subjective” chair to be discovered, the behaviorist derides the
introspectionist for dwelling in a world of imaginary ghosts. The
simple truth is that some of the experiences depending upon processes
in my physical organism have the character of “objectivity,” whereas
others, depending upon other processes in the same organism, have
a “subjective” character, this contrast being something altogether
indifferent to the _genetic_ “subjectivity” of _both_ types of
processes and experiences, as depending upon the physical organism.
After this, I hope that no misunderstanding of the term “objective
experience” will be possible. When I talk about “a chair,” the chair
of my everyday life is meant and not some “subjective phenomenon” to
be observed perhaps by highly trained introspectionists, but utterly
unknown to me.
On the other hand, we have seen that we cannot identify the chair of
“objective experience” with the chair as a part of the physicist’s
world. Under these circumstances, the world of direct experience being
the first I had, and since all that I know about the physical world
being inferred later on from the properties of the experienced world,
how can I deny this experienced world which, for me, is the only basis
upon which I can continue to guess about physical realities? No one
can prevent me from thinking, if I choose, that after all the physical
world may be the more important and more essential one. But even then
I must confess that the other world has existed first and always
_for me_, and that I still can see no other way of discovering the
properties of physical reality but by observing “objective experiences”
and drawing my conclusions about the physical world from them. With
future progress of physiology I may become able to discover even the
nervous processes underlying my “observing” and “guessing” and so be
able to give a physical theory of these events. But even then, since
the world of physiology is part of the physical world and _as such_ is
not directly accessible to me, any progress whatever along this line
will depend upon my observing what I call a body or a nervous system
as parts of “direct experience.” It may be otherwise for behaviorists,
so that the physical (and physiological) world _as such_ is directly
known to them, and that for them the term “known” has nothing to do
with direct experience. But that cannot change my report about my
own case in which affairs are as I have described them. It is in the
terms of this description that I must decide whether I shall become a
behaviorist or not.
What then about the behaviorist’s statement that observation in physics
deals with objective reality whereas, in the treatment of direct
experience, it deals with something subjective?
Let me describe my own procedure when I investigate the physical
properties of a physical object. Is there any considerable amount of
H_{4}C_{2}O_{2} in a given mixture of chemical substances? I know
about these substances by the corresponding “objective experience”
before me, and I find the positive answer to the question by smelling,
i.e., in direct experience. This being a rather crude procedure, let
us consider a case of fine measurement. What is the intensity of an
electric current which, under certain conditions, must exist in a given
wire? The position of a needle on the scale of a definite apparatus
will tell me, but it will tell me in direct optical experience, the
whole apparatus being an “objective” part of my actual experience,
exactly as the wire and the given set of conditions must manifest
themselves either as parts of direct experience or by a sufficient
testimony of their existence in some part of experience which I have
learnt to regard as a sign for them. And this is true of all possible
objective statements or measurements which I shall ever be able to make
in physics. They are statements about my actual objective experiences
in these different cases. I shall never be able to make a direct
statement about a physical event _as such_. Therefore my observation of
physical facts will always remain of the same kind in principle as that
of an after-image, or of the “confusion” which I find so characteristic
of peripheral vision, or of my feeling healthy. Therefore, the
exactness of my physical observation cannot depend upon my avoidance of
“direct experience” in physics. I do not avoid it, for I cannot avoid
it. Yet the procedure _works_. _Some_ observations of direct experience
must then be an adequate basis for science.
If all the concrete statements which I can make in physical research
are observations of direct experience, there are some inevitable
consequences. How do I define my terms as a physicist? Since my
knowledge of physics consists entirely of concepts and observations
derived from or contained in direct experience, all the terms which I
use in discussing physical problems must refer either to concepts or
observations or, more probably, complicated combinations of the two--in
any case, products of my direct experience. If I try to define them,
my definitions must refer to other concepts or observations, and so
forth. A gestural denotation toward the locus of the phenomena about
which I am talking, as, for instance, a hint where to make certain
observations or have certain direct experiences, will be the ultimate
step in any process of definition I may attempt. Even the most abstract
concepts of physics, as, for example, that of entropy, can have no
meaning without a reference, indirect though it may be, to truly direct
experiences. I shall never be able to give a definition of my terms in
physics or to understand a definition given by others, which, in this
respect, differs in principle from what I may use as a definition in
psychology. Nevertheless the method of physics is successful. I never
have difficulty with definitions when I talk with physicists about
their science. Hence some definitions, or hints about cases of direct
experience, must be sufficiently safe for exact science. Therefore the
exactness of my definitions in physics cannot be the result of their
being independent of “direct experience,” for they are not independent.
But the behaviorist tells me that observation of my direct experience
is a private affair of mine, whereas in physics, two physicists
can make the same observation on the same galvanometer. I deny the
truth of this statement. If another man observes the galvanometer,
he observes something other than the galvanometer as a physical
object, since the object of his observation is the result of certain
organic processes, determined by the physical galvanometer. Again,
the galvanometer I am observing is the final result of a different
series of processes occurring in _my_ physical organism. By no means
do we “observe the same instrument” then, though physically both
series of processes are started by the same physical object. Still,
our statements about our observations seem to agree so well in a great
many cases, that we do not discuss the question very much, whether
there is an absolute philosophical proof for sufficient similarity
between my galvanometer and his. Again the procedure works. Since I,
at least, do not know about a galvanometer except through “objective
experience,” and yet almost all the statements which the other man
makes agree with my statements, the privacy of direct experience does
not disturb us at all--in physics. Again, in principle, there is no
difference here between physics and psychology. All physicists,
when working with others in such a case, are convinced naïvely that
their fellow-physicists “have a galvanometer before them,” and that
their observations refer to it. In this sense they assume that their
fellow-workers have a very definite “objective experience,” highly
similar to their own experience, and they quite naïvely understand the
words of their colleagues as statements about that experience. That,
however, is allowing private affairs in exact science. It does not seem
to disturb scientific procedure, as it does not disturb the affairs of
everyday life, wherein it is the most general and natural occurrence.
In certain cases, therefore, belief in the “direct experience” of
others must be innocent and is not a hindrance to scientific progress.
If psychology does not make rapid advancement, the reason for it cannot
be that belief as such.
There remains one consequence of the elementary fact that observation
in physics involves observation of direct experience. As a physicist,
observing my apparatus, I do not fear that my activity as an observer
has any serious or distorting influence upon the essential properties
of what I observe, if only I keep myself, as a physical system, at
a certain distance from the apparatus, as another physical system.
Now, as direct experiences both the apparatus to be observed and my
“activity” of observing depend upon processes in the same system, viz.,
my physical organism. Again the behaviorist must be wrong when he
declares that, because of the fact just mentioned, direct experience
can not be observed scientifically, since in this case of observation
in physics, the situation is similar: the material to be observed and
the process of observing belong to the same system. Thus we see that
the physicist and the psychologist are in exactly the same situation
in this respect. It does not matter at all whether I call myself a
physicist or a psychologist in observing a galvanometer. In both cases
my observation is directed towards the same “objective experience.” The
procedure works in physics. Why not in psychology? There must be some
cases in which my observation of direct experience does not disturb the
observed facts seriously.
This argument contains in itself a most remarkable limitation of the
range of its own application. It does not mean at all, that all forms
of so-called introspection are justified, even less does it mean that
_generally_ the products of so-called introspection are independent
of introspection. Here the critical position of behaviorism has
exaggerated the scope of a fair argument and unjustly applied it to
_all_ statements about direct experience, although the critical point
is thoroughly justified in a great many cases.
I have described how, as a physicist, I must deal with direct
experience. Evidently some epistemological difficulties with respect
to the objectivity of procedure in that science may be derived from
that description by a very extreme purist, as the behaviorist seems
to be. But, fortunately, those dilemmas had not yet been discovered,
when in the time of Galileo, Newton and Huyghens the first really
important steps were made in physics. Those great investigators carried
on, pragmatically naïve and happily undisturbed by a “behaviorism” of
physics which might have impeded or blocked the whole development for
the sake of “epistemological purity.” Somehow the procedure has worked
in spite of the fact that logically, perhaps, it is not possible to
certify it as absolutely objective. Sciences which wish to carry on
their researches and be productive often show a certain healthy disdain
of such scruples. It might be better for psychology, too, if, after
listening to a very wholesome critical lesson from behaviorism, it
returns to undertaking productive work with some naïveté, using all
possible means which yield results.