MEMORY OBJECTIVELY REGARDED
We are concerned in these chapters with what we can know about other
men by merely observing their behaviour. In this chapter, I propose
to consider everything that would commonly be called “memory”, in so
far as it can be made a matter of external observation. And perhaps it
may be as well, at this point, to state my own view of the question
of “behaviourism”. This philosophy, of which the chief protagonist is
Dr. John B. Watson, holds that everything that can be known about man
is discoverable by the method of external observation, _i.e._ that
none of our knowledge depends, essentially and necessarily, upon data
in which the observer and the observed are the same person. I do not
fundamentally agree with this view, but I think it contains much more
truth than most people suppose, and I regard it as desirable to develop
the behaviourist method to the fullest possible extent. I believe that
the knowledge to be obtained by this method, so long as we take physics
for granted, is self-contained, and need not, at any point, appeal
to data derived from introspection, _i.e._ from observations which a
man can make upon himself but not upon any one else. Nevertheless,
I hold that there are such observations and that there is knowledge
which depends upon introspection. What is more, I hold that data of
this kind are required for a critical exposition of physics, which
behaviourism takes for granted. I shall, therefore, after setting forth
the behaviourist view of man, proceed to a scrutiny of our knowledge of
physics, returning thence to man, but now as viewed from within. Then,
finally, I shall attempt to draw conclusions as to what we know of the
universe in general.
The word “memory” or “remembering” is commonly used in a number
of different senses, which it is important to distinguish. More
especially, there is a broad sense, in which the word applies to the
power of repeating any habitual act previously learnt, and a narrow
sense, in which it applies only to recollection of past events. It is
in the broad sense that people speak of a dog remembering his master or
his name, and that Sir Francis Darwin spoke of memory in plants. Samuel
Butler used to attribute the sort of behaviour that would usually be
called instinctive to memory of ancestral experience, and evidently he
was using the word “memory” in its widest possible sense. Bergson, on
the contrary, dismisses “habit-memory” as not true memory at all. True
memory, for him, is confined to the recollection of a past occurrence,
which, he maintains, cannot be a habit, since the event remembered
only occurred once. The behaviourist maintains that this contention is
mistaken, and that all memory consists in the retention of a habit. For
him, therefore, memory is not something requiring special study, but
is merged into the study of habit. Dr. Watson says: “The behaviourist
never uses the term ‘memory’. He believes that it has no place in an
objective psychology.” He proceeds to give instances, beginning with a
white rat in a maze. On the first occasion, he says, it took this rat
forty minutes to get out of the maze, but after thirty-five trials he
learnt to get out in six seconds, without taking any wrong turnings. He
was then kept away from the maze for six months, and on being put in it
again he got out in two minutes, with six mistakes. He was just as good
as he had been before at the twentieth trial. We have here a measure of
the extent to which the habit of the maze had been retained. A similar
experiment with a monkey showed even more retentiveness. He was put
into a problem box which at first took him twenty minutes to open, but
at the twentieth trial he opened it in two seconds. He was then kept
away from it for six months, and on being put back in it he opened it
in four seconds.
With human beings, we know that many of the habits we learn are
retained through long periods of disuse--skating, bicycling, swimming,
golf, etc., are familiar instances. Perhaps Dr. Watson goes a trifle
too far when he says: “If a poor shot or an inexpert golfer tells you
that he was good five years ago but that lack of practice has made him
poor, don’t believe him; he never was good!” At any rate, this is not
the belief of violinists and pianists, who consider it essential to
practise every day. But even if it be somewhat of an exaggeration, it
is certainly true that we retain bodily habits pretty well. Some, such
as swimming, seem to be more completely retained than others. The power
of talking a foreign language, for example, is one which is greatly
impaired by disuse. The whole matter is quantitative, and easily tested
by experiment.
But memory in the sense of recollection of past events, if it can be
explained as a habit, will have, one might suppose, to be a _verbal_
habit. As to this, Dr. Watson says:
“What the man on the street ordinarily means by an exhibition of memory
is what occurs in some such situation as this: An old friend comes to
see him, after many years’ absence. The moment he sees this friend,
he says: ‘Upon my life! Addison Sims of Seattle! I haven’t seen you
since the World’s Fair in Chicago. Do you remember the gay parties we
used to have in the Wilderness Hotel? Do you remember the Midway? Do
you remember ... etc.,’ _ad infinitum_. The psychology of this process
is so simple that it seems almost an insult to your intelligence to
discuss it, and yet a good many of the behaviourists’ kindly critics
have said that behaviourism cannot adequately explain memory. Let us
see if this is a fact.”
He goes on to say that during the period, long ago, when the man on
the street was seeing Mr. Sims, they formed verbal and manual habits
towards one another, so that “finally, just the sight of man, even
after months of absence, would call out not only the old verbal
habits, but many other types of bodily and visceral responses.”
He sums up: “By ‘memory’, then, we mean nothing except the
fact that when we meet a stimulus again after an absence, we
do the old habitual thing (say the old words and show the old
visceral--emotional--behaviour) that we learned to do when we were in
the presence of that stimulus in the first place.”
This theory is preferable to ordinary psychological theories in many
ways. In the first place, it is not an attempt to treat memory as
some sort of mystical “faculty”, and does not suppose that we are
always remembering everything that we should remember if a suitable
stimulus were applied. It is concerned with the causation of specific
acts of remembering, these acts being all externally observable. I do
not see any good reason to question it. Bergson’s contention that the
recollection of a unique occurrence cannot be explained by habit is
clearly fallacious. There are many instances, both with animals and
with human beings, of a habit becoming firmly established through one
experience. It is, therefore, quite possible that a stimulus associated
with a previous occurrence should set going a train of bodily events
which, in turn, produce words describing that occurrence. There is
here, however, a difficulty. The memory of a past occurrence cannot
be a _verbal_ habit, except when the occurrence has been frequently
related. When Watson’s man on the street says “Do you remember the
Midway”, he is not using words that have become habitual; very likely
he never used these words before. He is using words which a verbal
habit associates with an event that is now happening in him, and the
event is called up by a habit associated with Mr. Sims. So at least
we must suppose, if we accept Watson’s view. But this diminishes the
plausibility and the verifiability of his view. It is not our actual
language that can be regarded as habitual, but only what our words
express. In repeating a poem we have learned by heart, the language is
habitual, but not so when we recount a past incident in words we never
used before. In this case, it is not the actual words that we repeat,
but only their meaning. The habitual element, therefore, if it really
accounts for the recollection, must not be sought in words.
This is something of a difficulty in the Watsonian theory of language.
When a rat learns a maze, it learns certain definite bodily movements;
so do we when we learn by heart. But I may say to one person, “I met
Mr. Jones in the train to-day”, and to another “Joseph was in the
9.35 this morning.” With the exception of the words “in the”, these
two sentences have nothing verbally in common, yet they may relate
the same fact, and I may use either indifferently when I recall the
fact. Thus my recollection is certainly _not_ a definite verbal
habit. Yet words are the only overt bodily movements by which I make
known my recollections to other people. If the behaviourist tells me
that my recollection is bodily habit, and begins by telling me that
it is a _verbal_ habit, he can be driven by such instances to the
admission that it must be some other kind of habit. If he says this,
he is abandoning the region of observable fact, and taking refuge in
hypothetical bodily movements invoked to save a theory. But these are
hardly any better than “thoughts.”
This question is more general than the problem of memory. Many
different forms of words may be used to express the same “meaning”, and
there seems no reason in mere habit to account for the fact that we
sometimes use one form of words and sometimes another when we “think”
of that which all the various forms of words express. The association
seems to go, not direct from stimulus to words, but from stimulus to
“meaning” and thence to words expressing the “meaning”. You may, for
instance, be quite unable to recollect whether you were told “Jacob is
older than Joseph”, or “Joseph is younger than Jacob”, though you may
remember quite definitely that you were told the fact which both these
forms of words express. Again, if you are learning, say, a proof of a
mathematical theorem, you do not learn by heart what the book says,
unless you are a very bad mathematician; you learn, as people say, to
“understand” the proof, and then you can reproduce it in symbols quite
different from those in the book. It is such facts, among others, that
make it difficult to explain the mechanism of association, whether in
memory or in “thought” in general, if we assume that words, or even
sentences, are the terms associated.
Perhaps, however, the theory as to the “meaning” of words which we
developed in an earlier chapter may help us out of the difficulty.
We defined the “meaning” of a word by means of its associations;
therefore, if two words are synonyms, they have the same associations;
and any stimulus which calls up one may also call up the other. The
question which of two synonyms we use will then depend upon some
extraneous circumstance.
This is all very well so far as single words are concerned; it would
account satisfactorily, for instance, for the fact that I call a man
sometimes by his surname and sometimes by his Christian name. But it
is hardly so adequate when we come to the question of sentences. To
revert to the illustration of a moment ago, in response to the stimulus
“Did anything happen on your journey?” you may say either “I met Mr.
Jones in the train to-day”, or “Joseph was in the 9.35 this morning”,
or any one of an indefinite number of other sentences expressive of the
same occurrence. Are we to suppose that, while you were in the train,
you were rehearsing all these different sentences to yourself, so that
each of them became firmly associated with the words “journey to-day”?
Clearly such a supposition would be absurd. Yet all the separate words
of your sentence have many other associations; it is only the sentence
as a whole that is associated with your journey. You have met other
people besides Mr. Jones; you have had other contacts with Mr. Jones
besides meeting him this morning; “train” and “to-day” equally are
appropriate to other occurrences that you might relate. Thus it has
to be the whole sentence that is the associative unit, and yet the
sentence may never have been in your head before. It seems clear that
it is possible to state in words something that you remember, although
you never put it into words before. Suppose I say “What did you have
for breakfast to-day?” Probably you will be able to tell me, though
it is very likely that you have not given names to the things you ate
until this moment.
This whole matter is connected with the distinction between sentences
and single words, which we found important when we were discussing
language. But even when we confine ourselves to single words, there
are difficulties in Dr. Watson’s view. Cases are alleged in which
children, after learning to speak, can recall incidents which occurred
before they could speak, and describe them in correct words. This would
show that the memory had persisted in a non-verbal form throughout
the period before they learned to speak, and had only subsequently
found verbal expression. Such extreme incidents are rare and might be
questioned, but in a less extreme form it ought not to be difficult to
obtain examples of the same sort of thing. Suppose, for example, that a
young child hurt his wrist badly before he knew the word “wrist”, and
that some time afterwards he learnt it; I should not be surprised if he
could relate that he had hurt his wrist. Such instances, however, would
not refute the essence of Watson’s theory. He would allow “visceral”
memory, for example, and the association with the word “wrist” might
be grafted on to this. The real difficulty in Dr. Watson’s view, to my
mind, is the fact that our sentence may vary verbally as much as it
likes so long as it retains the same “meaning”, and that we clearly do
not rehearse to ourselves beforehand all the possible sentences having
the “meaning” in question.
It should be realised that behaviourism loses much of its
attractiveness if it is compelled to postulate movements that no one
can observe and that there is no other reason to assume. Dr. Broad,
in his book on _The Mind and its Place in Nature_, distinguishes
between “molar” and “molecular” behaviourism: the former assumes only
such bodily movements as can be observed, while the latter allows
and utilises hypothetical minute movements, more especially in the
brain. Now here we must make a distinction. Physics believes in a large
number of phenomena which are too minute to be observed even with the
strongest microscope, and if physics is at all correct, there must be
minute movements in all parts of a human body, of a sort which we can
never hope to see. We cannot reasonably demand of the behaviourist that
he should abstain from an hypothesis which physics asserts for very
good reasons. And in the process which leads from stimulus to reaction
there are bound to be small occurrences in the brain, which, though
they cannot be observed, are essential to the physiological explanation
of what occurs. But when the behaviourist assumes small occurrences
for which there is no ground in physics, and which are needed solely
in order to safeguard his theory, he is in a less strong position.
Dr. Watson asserts, for instance, that whenever we “think” there are
small movements in the larynx which are beginnings of the movements we
should make as if we spoke words out loud. It may be that this is true;
certainly I am not prepared to deny it. But I am not prepared to say
that it _must_ be true merely because, if it were not, behaviourism
would be false. We do not know in advance that behaviourism is true;
we have to find out whether it will explain observed facts. Whenever
it has to postulate something unobserved merely in order to avoid a
refutation, it weakens its case. And if it maintains, as, from Dr.
Watson’s language, it seems to do, that we only remember an occurrence
by forming a verbal habit in connection with it, then it is obliged to
postulate much implicit use of words of which we have no evidence.
To sum up this discussion. While it is quite possible, by behaviourist
methods, to ascertain whether a person remembers a past occurrence or
not, unless he is deliberately obstructing the observer, and while
much memory can be quite adequately explained as habit, there do seem
to be great difficulties in the view that memory consists _entirely_
of habit, at least in the case of the recollection of an event. These
difficulties seem insuperable if we suppose memory to be _essentially_
a verbal habit. They are not insuperable if we postulate sufficient
minute unobservable bodily movements. We have not considered whether
they can be overcome by introducing data derived from introspection,
since we wish, for the present, to maintain a strictly objective
attitude to human behaviour. The introspective discussion of memory
will be taken up at a later stage.