It is said to be one of the merits of the human mind that it is capable
of framing abstract ideas, and of conducting nonsensational thought.
In this it is supposed to differ from the mind of animals. From Plato
onward the "idea" has played a great part in the systems of idealizing
philosophers. The "idea" has been, in their hands, always something
noble and abstract, the apprehension and use of which by man confers
upon him a quite special dignity.
The thing we have to consider to-day is this: seeing that there
certainly are words of which the meaning is abstract, and seeing that we
can use these words intelligently, what must be assumed or inferred, or
what can be discovered by observation, in the way of mental content to
account for the intelligent use of abstract words?
Taken as a problem in logic, the answer is, of course, that absolutely
nothing in the way of abstract mental content is inferable from the
mere fact that we can use intelligently words of which the meaning
is abstract. It is clear that a sufficiently ingenious person could
manufacture a machine moved by olfactory stimuli which, whenever a dog
appeared in its neighbourhood, would say, "There is a dog," and when
a cat appeared would throw stones at it. The act of saying "There is a
dog," and the act of throwing stones, would in such a case be equally
mechanical. Correct speech does not of itself afford any better evidence
of mental content than the performance of any other set of biologically
useful movements, such as those of flight or combat. All that is
inferable from language is that two instances of a universal, even when
they differ very greatly, may cause the utterance of two instances
of the same word which only differ very slightly. As we saw in the
preceding lecture, the word "dog" is useful, partly, because two
instances of this word are much more similar than (say) a pug and a
great dane. The use of words is thus a method of substituting for two
particulars which differ widely, in spite of being instances of the same
universal, two other particulars which differ very little, and which
are also instances of a universal, namely the name of the previous
universal. Thus, so far as logic is concerned, we are entirely free to
adopt any theory as to general ideas which empirical observation may
recommend.
Berkeley and Hume made a vigorous onslaught on "abstract ideas." They
meant by an idea approximately what we should call an image. Locke
having maintained that he could form an idea of triangle in general,
without deciding what sort of triangle it was to be, Berkeley contended
that this was impossible. He says:
"Whether others, have this wonderful faculty of abstracting their ideas,
they best can tell: for myself, I dare be confident I have it not. I
find, indeed, I have indeed a faculty of imagining, or representing to
myself, the ideas of those particular things I have perceived, and of
variously compounding and dividing them. I can imagine a man with two
heads, or the upper parts of a man joined to the body of a horse. I
can consider the hand, the eye, the nose, each by itself abstracted or
separated from the rest of the body. But, then, whatever hand or eye
I imagine, it must have some particular shape and colour. Likewise the
idea of a man that I frame to myself must be either of a white, or a
black, or a tawny, a straight, or a crooked, a tall, or a low, or
a middle-sized man. I cannot by any effort of thought conceive the
abstract idea above described. And it is equally impossible for me to
form the abstract idea of motion distinct from the body moving, and
which is neither swift nor slow, curvilinear nor rectilinear; and the
like may be said of all other abstract general ideas whatsoever. To be
plain, I own myself able to abstract in one sense, as when I consider
some particular parts of qualities separated from others, with which,
though they are united in some object, yet it is possible they may
really exist without them. But I deny that I can abstract from one
another, or conceive separately, those qualities which it is impossible
should exist so separated; or that I can frame a general notion, by
abstracting from particulars in the manner aforesaid--which last are
the two proper acceptations of ABSTRACTION. And there is ground to think
most men will acknowledge themselves to be in my case. The generality of
men which are simple and illiterate never pretend to ABSTRACT NOTIONS.
It is said they are difficult and not to be attained without pains and
study; we may therefore reasonably conclude that, if such there be, they
are confined only to the learned.
"I proceed to examine what can be alleged in defence of the doctrine of
abstraction, and try if I can discover what it is that inclines the men
of speculation to embrace an opinion so remote from common sense as that
seems to be. There has been a late excellent and deservedly esteemed
philosopher who, no doubt, has given it very much countenance, by
seeming to think the having abstract general ideas is what puts the
widest difference in point of understanding betwixt man and beast.
'The having of general ideas,' saith he, 'is that which puts a perfect
distinction betwixt man and brutes, and is an excellency which the
faculties of brutes do by no means attain unto. For, it is evident
we observe no footsteps in them of making use of general signs for
universal ideas; from which we have reason to imagine that they have not
the faculty of abstracting, or making general ideas, since they have
no use of words or any other general signs.' And a little after:
'Therefore, I think, we may suppose that it is in this that the species
of brutes are discriminated from men, and it is that proper difference
wherein they are wholly separated, and which at last widens to so wide a
distance. For, if they have any ideas at all, and are not bare machines
(as some would have them), we cannot deny them to have some reason. It
seems as evident to me that they do, some of them, in certain instances
reason as that they have sense; but it is only in particular ideas, just
as they receive them from their senses. They are the best of them tied
up within those narrow bounds, and have not (as I think) the faculty
to enlarge them by any kind of abstraction.* ("Essay on Human
Understanding," Bk. II, chap. xi, paragraphs 10 and 11.) I readily agree
with this learned author, that the faculties of brutes can by no means
attain to abstraction. But, then, if this be made the distinguishing
property of that sort of animals, I fear a great many of those that
pass for men must be reckoned into their number. The reason that is here
assigned why we have no grounds to think brutes have abstract general
ideas is, that we observe in them no use of words or any other general
signs; which is built on this supposition-that the making use of words
implies the having general ideas. From which it follows that men who use
language are able to abstract or generalize their ideas. That this is
the sense and arguing of the author will further appear by his answering
the question he in another place puts: 'Since all things that exist are
only particulars, how come we by general terms?' His answer is: 'Words
become general by being made the signs of general ideas.' ("Essay on
Human Understanding," Bk. III, chap. III, paragraph 6.) But it seems
that a word becomes general by being made the sign, not of an abstract
general idea, but of several particular ideas, any one of which it
indifferently suggests to the mind. For example, when it is said 'the
change of motion is proportional to the impressed force,' or that
'whatever has extension is divisible,' these propositions are to be
understood of motion and extension in general; and nevertheless it will
not follow that they suggest to my thoughts an idea of motion without
a body moved, or any determinate direction and velocity, or that I must
conceive an abstract general idea of extension, which is neither line,
surface, nor solid, neither great nor small, black, white, nor red,
nor of any other determinate colour. It is only implied that
whatever particular motion I consider, whether it be swift or slow,
perpendicular, horizontal, or oblique, or in whatever object, the axiom
concerning it holds equally true. As does the other of every particular
extension, it matters not whether line, surface, or solid, whether of
this or that magnitude or figure.
"By observing how ideas become general, we may the better judge how
words are made so. And here it is to be noted that I do not deny
absolutely there are general ideas, but only that there are any ABSTRACT
general ideas; for, in the passages we have quoted wherein there is
mention of general ideas, it is always supposed that they are formed by
abstraction, after the manner set forth in sections 8 and 9. Now, if
we will annex a meaning to our words, and speak only of what we can
conceive, I believe we shall acknowledge that an idea which, considered
in itself, is particular, becomes general by being made to represent
or stand for all other particular ideas of the same sort. To make this
plain by an example, suppose a geometrician is demonstrating the method
of cutting a line in two equal parts. He draws, for instance, a black
line of an inch in length: this, which in itself is a particular line,
is nevertheless with regard to its signification general, since, as it
is there used, it represents all particular lines whatsoever; so that
what is demonstrated of it is demonstrated of all lines, or, in other
words, of a line in general. And, as THAT PARTICULAR LINE becomes
general by being made a sign, so the NAME 'line,' which taken absolutely
is particular, by being a sign is made general. And as the former owes
its generality not to its being the sign of an abstract or general line,
but of all particular right lines that may possibly exist, so the latter
must be thought to derive its generality from the same cause, namely,
the various particular lines which it indifferently denotes." *
* Introduction to "A Treatise concerning the Principles of
Human Knowledge," paragraphs 10, 11, and 12.
Berkeley's view in the above passage, which is essentially the same as
Hume's, does not wholly agree with modern psychology, although it comes
nearer to agreement than does the view of those who believe that there
are in the mind single contents which can be called abstract ideas. The
way in which Berkeley's view is inadequate is chiefly in the fact that
images are as a rule not of one definite prototype, but of a number of
related similar prototypes. On this subject Semon has written well.
In "Die Mneme," pp. 217 ff., discussing the effect of repeated similar
stimuli in producing and modifying our images, he says: "We choose a
case of mnemic excitement whose existence we can perceive for ourselves
by introspection, and seek to ekphore the bodily picture of our nearest
relation in his absence, and have thus a pure mnemic excitement before
us. At first it may seem to us that a determinate quite concrete picture
becomes manifest in us, but just when we are concerned with a person
with whom we are in constant contact, we shall find that the ekphored
picture has something so to speak generalized. It is something like
those American photographs which seek to display what is general about a
type by combining a great number of photographs of different heads over
each other on one plate. In our opinion, the generalizations happen by
the homophonic working of different pictures of the same face which we
have come across in the most different conditions and situations, once
pale, once reddened, once cheerful, once earnest, once in this
light, and once in that. As soon as we do not let the whole series
of repetitions resound in us uniformly, but give our attention to one
particular moment out of the many... this particular mnemic stimulus at
once overbalances its simultaneously roused predecessors and successors,
and we perceive the face in question with concrete definiteness in that
particular situation." A little later he says: "The result is--at least
in man, but probably also in the higher animals--the development of a
sort of PHYSIOLOGICAL abstraction. Mnemic homophony gives us, without
the addition of other processes of thought, a picture of our friend
X which is in a certain sense abstract, not the concrete in any one
situation, but X cut loose from any particular point of time. If the
circle of ekphored engrams is drawn even more widely, abstract pictures
of a higher order appear: for instance, a white man or a negro. In my
opinion, the first form of abstract concepts in general is based upon
such abstract pictures. The physiological abstraction which takes
place in the above described manner is a predecessor of purely logical
abstraction. It is by no means a monopoly of the human race, but shows
itself in various ways also among the more highly organized animals."
The same subject is treated in more detail in Chapter xvi of "Die
mnemischen Empfindungen," but what is said there adds nothing vital to
what is contained in the above quotations.
It is necessary, however, to distinguish between the vague and the
general. So long as we are content with Semon's composite image, we MAY
get no farther than the vague. The question whether this image takes us
to the general or not depends, I think, upon the question whether, in
addition to the generalized image, we have also particular images
of some of the instances out of which it is compounded. Suppose, for
example, that on a number of occasions you had seen one negro, and
that you did not know whether this one was the same or different on
the different occasions. Suppose that in the end you had an abstract
memory-image of the different appearances presented by the negro on
different occasions, but no memory-image of any one of the single
appearances. In that case your image would be vague. If, on the other
hand, you have, in addition to the generalized image, particular images
of the several appearances, sufficiently clear to be recognized as
different, and as instances of the generalized picture, you will then
not feel the generalized picture to be adequate to any one particular
appearance, and you will be able to make it function as a general
idea rather than a vague idea. If this view is correct, no new general
content needs to be added to the generalized image. What needs to be
added is particular images compared and contrasted with the generalized
image. So far as I can judge by introspection, this does occur in
practice. Take for example Semon's instance of a friend's face. Unless
we make some special effort of recollection, the face is likely to come
before us with an average expression, very blurred and vague, but we can
at will recall how our friend looked on some special occasion when he
was pleased or angry or unhappy, and this enables us to realize the
generalized character of the vague image.
There is, however, another way of distinguishing between the vague, the
particular and the general, and this is not by their content, but by
the reaction which they produce. A word, for example, may be said to be
vague when it is applicable to a number of different individuals, but to
each as individuals; the name Smith, for example, is vague: it is always
meant to apply to one man, but there are many men to each of whom it
applies.* The word "man," on the other hand, is general. We say, "This
is Smith," but we do not say "This is man," but "This is a man." Thus
we may say that a word embodies a vague idea when its effects are
appropriate to an individual, but are the same for various similar
individuals, while a word embodies a general idea when its effects are
different from those appropriate to individuals. In what this difference
consists it is, however, not easy to say. I am inclined to think that it
consists merely in the knowledge that no one individual is represented,
so that what distinguishes a general idea from a vague idea is merely
the presence of a certain accompanying belief. If this view is correct,
a general idea differs from a vague one in a way analogous to that in
which a memory-image differs from an imagination-image. There also
we found that the difference consists merely of the fact that a
memory-image is accompanied by a belief, in this case as to the past.
* "Smith" would only be a quite satisfactory representation
of vague words if we failed to discriminate between
different people called Smith.
It should also be said that our images even of quite particular
occurrences have always a greater or a less degree of vagueness. That is
to say, the occurrence might have varied within certain limits without
causing our image to vary recognizably. To arrive at the general it
is necessary that we should be able to contrast it with a number of
relatively precise images or words for particular occurrences; so long
as all our images and words are vague, we cannot arrive at the contrast
by which the general is defined. This is the justification for the
view which I quoted on p. 184 from Ribot (op. cit., p. 32), viz. that
intelligence progresses from the indefinite to the definite, and that
the vague appears earlier than either the particular or the general.
I think the view which I have been advocating, to the effect that a
general idea is distinguished from a vague one by the presence of a
judgment, is also that intended by Ribot when he says (op. cit., p. 92):
"The generic image is never, the concept is always, a judgment. We know
that for logicians (formerly at any rate) the concept is the simple
and primitive element; next comes the judgment, uniting two or several
concepts; then ratiocination, combining two or several judgments. For
the psychologists, on the contrary, affirmation is the fundamental
act; the concept is the result of judgment (explicit or implicit), of
similarities with exclusion of differences."
A great deal of work professing to be experimental has been done in
recent years on the psychology of thought. A good summary of such
work up to the year agog is contained in Titchener's "Lectures on the
Experimental Psychology of the Thought Processes" (1909). Three articles
in the "Archiv fur die gesammte Psychologie" by Watt,* Messer** and
Buhler*** contain a great deal of the material amassed by the methods
which Titchener calls experimental.
* Henry J. Watt, "Experimentelle Beitrage zu einer Theorie
des Denkens," vol. iv (1905) pp. 289-436.
** August Messer, "Experimentell-psychologische Untersuchu
gen uber das Denken," vol. iii (1906), pp. 1-224.
*** Karl Buhler, "Uber Gedanken," vol. ix (1907), pp. 297-365.
For my part I am unable to attach as much importance to this work as
many psychologists do. The method employed appears to me hardly to
fulfil the conditions of scientific experiment. Broadly speaking, what
is done is, that a set of questions are asked of various people, their
answers are recorded, and likewise their own accounts, based upon
introspection, of the processes of thought which led them to give
those answers. Much too much reliance seems to me to be placed upon the
correctness of their introspection. On introspection as a method I have
spoken earlier (Lecture VI). I am not prepared, like Professor Watson,
to reject it wholly, but I do consider that it is exceedingly fallible
and quite peculiarly liable to falsification in accordance with
preconceived theory. It is like depending upon the report of a
shortsighted person as to whom he sees coming along the road at a moment
when he is firmly convinced that Jones is sure to come. If everybody
were shortsighted and obsessed with beliefs as to what was going to be
visible, we might have to make the best of such testimony, but we should
need to correct its errors by taking care to collect the simultaneous
evidence of people with the most divergent expectations. There is no
evidence that this was done in the experiments in question, nor indeed
that the influence of theory in falsifying the introspection was at all
adequately recognized. I feel convinced that if Professor Watson had
been one of the subjects of the questionnaires, he would have given
answers totally different from those recorded in the articles in
question. Titchener quotes an opinion of Wundt on these investigations,
which appears to me thoroughly justified. "These experiments," he says,
"are not experiments at all in the sense of a scientific methodology;
they are counterfeit experiments, that seem methodical simply because
they are ordinarily performed in a psychological laboratory, and involve
the co-operation of two persons, who purport to be experimenter and
observer. In reality, they are as unmethodical as possible; they possess
none of the special features by which we distinguish the introspections
of experimental psychology from the casual introspections of everyday
life."* Titchener, of course, dissents from this opinion, but I cannot
see that his reasons for dissent are adequate. My doubts are only
increased by the fact that Buhler at any rate used trained psychologists
as his subjects. A trained psychologist is, of course, supposed to have
acquired the habit of observation, but he is at least equally likely to
have acquired a habit of seeing what his theories require. We may take
Buhler's "Uber Gedanken" to illustrate the kind of results arrived at
by such methods. Buhler says (p. 303): "We ask ourselves the general
question: 'WHAT DO WE EXPERIENCE WHEN WE THINK?' Then we do not at all
attempt a preliminary determination of the concept 'thought,' but choose
for analysis only such processes as everyone would describe as
processes of thought." The most important thing in thinking, he says, is
"awareness that..." (Bewusstheit dass), which he calls a thought. It
is, he says, thoughts in this sense that are essential to thinking.
Thinking, he maintains, does not need language or sensuous
presentations. "I assert rather that in principle every object can be
thought (meant) distinctly, without any help from sensuous presentation
(Anschauungshilfen). Every individual shade of blue colour on the
picture that hangs in my room I can think with complete distinctness
unsensuously (unanschaulich), provided it is possible that the object
should be given to me in another manner than by the help of sensations.
How that is possible we shall see later." What he calls a thought
(Gedanke) cannot be reduced, according to him, to other psychic
occurrences. He maintains that thoughts consist for the most part of
known rules (p. 342). It is clearly essential to the interest of this
theory that the thought or rule alluded to by Buhler should not need to
be expressed in words, for if it is expressed in words it is immediately
capable of being dealt with on the lines with which the behaviourists
have familiarized us. It is clear also that the supposed absence of
words rests solely upon the introspective testimony of the persons
experimented upon. I cannot think that there is sufficient certainty
of their reliability in this negative observation to make us accept a
difficult and revolutionary view of thought, merely because they have
failed to observe the presence of words or their equivalent in their
thinking. I think it far more likely, especially in view of the fact
that the persons concerned were highly educated, that we are concerned
with telescoped processes, in which habit has caused a great many
intermediate terms to be elided or to be passed over so quickly as to
escape observation.
* Titchener, op. cit., p. 79.
I am inclined to think that similar remarks apply to the general idea of
"imageless thinking," concerning which there has been much controversy.
The advocates of imageless thinking are not contending merely that there
can be thinking which is purely verbal; they are contending that there
can be thinking which proceeds neither in words nor in images. My own
feeling is that they have rashly assumed the presence of thinking in
cases where habit has rendered thinking unnecessary. When Thorndike
experimented with animals in cages, he found that the associations
established were between a sensory stimulus and a bodily movement (not
the idea of it), without the need of supposing any non-physiological
intermediary (op. cit., p. 100 ff.). The same thing, it seems to me,
applies to ourselves. A certain sensory situation produces in us a
certain bodily movement. Sometimes this movement consists in uttering
words. Prejudice leads us to suppose that between the sensory
stimulus and the utterance of the words a process of thought must have
intervened, but there seems no good reason for such a supposition. Any
habitual action, such as eating or dressing, may be performed on the
appropriate occasion, without any need of thought, and the same seems
to be true of a painfully large proportion of our talk. What applies to
uttered speech applies of course equally to the internal speech which is
not uttered. I remain, therefore, entirely unconvinced that there is
any such phenomenon as thinking which consists neither of images nor of
words, or that "ideas" have to be added to sensations and images as part
of the material out of which mental phenomena are built.
The question of the nature of our consciousness of the universal is
much affected by our view as to the general nature of the relation of
consciousness to its object. If we adopt the view of Brentano, according
to which all mental content has essential reference to an object, it
is then natural to suppose that there is some peculiar kind of mental
content of which the object is a universal, as oppose to a particular.
According to this view, a particular cat can be PERceived or imagined,
while the universal "cat" is CONceived. But this whole manner of viewing
our dealings with universals has to be abandoned when the relation of
a mental occurrence to its "object" is regarded as merely indirect and
causal, which is the view that we have adopted. The mental content is,
of course, always particular, and the question as to what it "means"
(in case it means anything) is one which cannot be settled by merely
examining the intrinsic character of the mental content, but only by
knowing its causal connections in the case of the person concerned. To
say that a certain thought "means" a universal as opposed to either a
vague or a particular, is to say something exceedingly complex. A horse
will behave in a certain manner whenever he smells a bear, even if
the smell is derived from a bearskin. That is to say, any environment
containing an instance of the universal "smell of a bear" produces
closely similar behaviour in the horse, but we do not say that the horse
is conscious of this universal. There is equally little reason to
regard a man as conscious of the same universal, because under the same
circumstances he can react by saying, "I smell a bear." This reaction,
like that of the horse, is merely closely similar on different occasions
where the environment affords instances of the same universal. Words
of which the logical meaning is universal can therefore be employed
correctly, without anything that could be called consciousness of
universals. Such consciousness in the only sense in which it can be
said to exist is a matter of reflective judgment consisting in the
observation of similarities and differences. A universal never appears
before the mind as a single object in the sort of way in which something
perceived appears. I THINK a logical argument could be produced to show
that universals are part of the structure of the world, but they are
an inferred part, not a part of our data. What exists in us consists of
various factors, some open to external observation, others only visible
to introspection. The factors open to external observation are primarily
habits, having the peculiarity that very similar reactions are produced
by stimuli which are in many respects very different from each other. Of
this the reaction of the horse to the smell of the bear is an instance,
and so is the reaction of the man who says "bear" under the same
circumstances. The verbal reaction is, of course, the most important
from the point of view of what may be called knowledge of universals. A
man who can always use the word "dog" when he sees a dog may be said,
in a certain sense, to know the meaning of the word "dog," and IN THAT
SENSE to have knowledge of the universal "dog." But there is, of course,
a further stage reached by the logician in which he not merely reacts
with the word "dog," but sets to work to discover what it is in the
environment that causes in him this almost identical reaction on
different occasions. This further stage consists in knowledge of
similarities and differences: similarities which are necessary to the
applicability of the word "dog," and differences which are compatible
with it. Our knowledge of these similarities and differences is never
exhaustive, and therefore our knowledge of the meaning of a universal is
never complete.
In addition to external observable habits (including the habit of
words), there is also the generic image produced by the superposition,
or, in Semon's phrase, homophony, of a number of similar perceptions.
This image is vague so long as the multiplicity of its prototypes is not
recognized, but becomes universal when it exists alongside of the more
specific images of its instances, and is knowingly contrasted with them.
In this case we find again, as we found when we were discussing words
in general in the preceding lecture, that images are not logically
necessary in order to account for observable behaviour, i.e. in this
case intelligent speech. Intelligent speech could exist as a motor
habit, without any accompaniment of images, and this conclusion applies
to words of which the meaning is universal, just as much as to words of
which the meaning is relatively particular. If this conclusion is valid,
it follows that behaviourist psychology, which eschews introspective
data, is capable of being an independent science, and of accounting
for all that part of the behaviour of other people which is commonly
regarded as evidence that they think. It must be admitted that this
conclusion considerably weakens the reliance which can be placed upon
introspective data. They must be accepted simply on account of the
fact that we seem to perceive them, not on account of their supposed
necessity for explaining the data of external observation.
This, at any rate, is the conclusion to which we are forced, so long
as, with the behaviourists, we accept common-sense views of the physical
world. But if, as I have urged, the physical world itself, as known,
is infected through and through with subjectivity, if, as the theory
of relativity suggests, the physical universe contains the diversity of
points of view which we have been accustomed to regard as distinctively
psychological, then we are brought back by this different road to the
necessity for trusting observations which are in an important sense
private. And it is the privacy of introspective data which causes much
of the behaviourists' objection to them.
This is an example of the difficulty of constructing an adequate
philosophy of any one science without taking account of other sciences.
The behaviourist philosophy of psychology, though in many respects
admirable from the point of view of method, appears to me to fail in
the last analysis because it is based upon an inadequate philosophy of
physics. In spite, therefore, of the fact that the evidence for images,
whether generic or particular, is merely introspective, I cannot
admit that images should be rejected, or that we should minimize their
function in our knowledge of what is remote in time or space.