Chapter XVI
).
One might speculate that in the formation of picture-strip memories these
older, primitive levels in the hierarchy play a dominant part. There are
some further considerations in favour of such a hypothesis. Abstractive
memory generalises and schematises, while the picture-strip particularises
and concretises -- which is a much more primitive method of storing
information.*
* The term 'information' in modern communication-theory is used in a
more general sense than in common parlance. It means any input
which 'informs' the organism, i.e., reduces its uncertainty. Thus
information includes anything from the colour and taste of an apple
to the Ninth Symphony of Beethoven. Irrelevant inputs -- i.e.,
those which do not reduce uncertainty -- convey no information and
are called 'noise' -- on the analogy of a noisy telephone line.
Abstractive memory may be compared with insightful learning, the
picture-strip with conditioning. It may also be related to so-called
eidetic images. It has been experimentally established [3] that a
considerable percentage of children have this faculty. The child is
told to fixate his eyes on a picture for about fifteen seconds, and
is afterwards able to see it 'projected' on an empty screen, to point
out the exact location of each detail, its colour, etc.
Eidetic images occupy an intermediary position between retinal
after-images and what we commonly call 'memory images'; Kluever speaks
of these three types or levels of visual memory, and seems to imply that
they are hierarchically ordered. Unlike after-images, eidetic images
can be produced at will, and after long intervals (even years). They
are like hallucinations, except that the child knows that the picture
he sees is not 'real'.
But though quite common in children, eidetic memory fades with the onset
of puberty and is rare among adults. Children live in a world of vivid
imagery: the eidetic child's way of 'imprinting' pictures on the mind
may represent a phylogenetically and ontogenetically earlier form of
memory-formation -- which is lost when abstractive, conceptual thinking
becomes dominant.
Images and Schemata
Leaving eidetics and picture-strips aside, when normal adults talk about
their memory images and assert that they can literally 'see' a remembered
scene or face in their mind's eye, they are usually victims of a subde
form of self-deception. One way of showing this is the Binet-Muller
test. The subject is asked to concentrate on a letter-square of, say,
five rows of five letters each, until he thinks that he has formed a
visual image of the square which he can 'see' in his mind's eye. When the
square is taken away, he can in fact fluently 'read' out the letters --
or so he thinks. But when asked to 'read' the square back to front or
diagonally, he will take up to ten times longer. He honestly believes
that he has formed a visual image, whereas in fact he has learned the
sequence by rote; if he could really 'see' the square, he could read it
in all directions with equal speed and ease.
This fallacy has been known for a long time. One of the earliest students
of the subject, Richard Semon (who coined the word 'mneme' for memory),
wrote half a century ago that visual recall 'renders only the strongest
lights and shadows'. In fact, even shadows are usually absent from visual
memories, and all but the crudest shades of colour. An image is defined
as 'a revived sense-experience in the absence of sensory stimulation'
[4]; but since most details of the experience were lost in the filtering
process of memory-formation, our visual images are much vaguer and
sketchier than we are wont to believe. They are skeletonised visual
generalisations -- outlines, patterns, schemata -- abstracted from the
original output by several interlocking visual hierarchies, much as
the melody, the timbre of voice and the words are extracted from the
Caruso aria.
We use various, often confusing, words for these optic schemata --
confusing because visual configurations are not easily translated
into verbal terms. Yet the caricaturist can evoke the face of Hitler
or Mao by a surprisingly few strokes, which schematise what we call a
'general impression'; adding perhaps a 'vivid detail', by sticking a
cigar in Churchill's mouth. When we try to describe a person's face,
we use expressions like 'bony', 'humorous', 'brutal', 'sad'. Verbally,
each of these attributes is extremely difficult to define; visually,
they are generalisations stripped of detail, but each definable by a
few strokes of a pencil: they are perceptual holons.
Recognising a person does not mean matching his retinal image against a
lantern-slide in the memory-store containing his photographic likeness;
it means subjecting the input to a hierarchy of scanning devices which
extract from it certain basic configurations -- the 'R-nesses', so to
speak. Several perceptual hierarchies may collaborate in the task. A
face, or a landscape, may have a 'melody', a 'timbre', a 'message'
and several other attributes. My attitude to the person or landscape
will determine which aspects are to be considered as relevant, to be
abstracted and stored, and which to be filtered out. For purposes of
recognition, the 'melody' alone may be sufficient. But the recall of the
face in its absence will be the more complete the more branches of the
perceptual hierarchy have participated in retaining it. The richer the
network connecting them, the more effectively it will compensate for the
impoverishment of experience in the process of storing it. The outstanding
memories which some great men are said to have possessed may be due to
this multi-dimensional way of analysing and storing experiences.*
* In the language of the information theorist: 'When information
is put in outline form, it is easy to include information about the
relations among the major parts and information about the internal
relations of parts in each of the sub-outlines. Detailed information
about the relations of sub-parts belonging to different parts
has no place in the outline and is likely to be lost. The loss of
such information and the preservation mainly of information about
hierarchic order is a salient characteristic that distinguishes
the drawings of a child or someone untrained in representation from
the drawing of a trained artist' (Simon [5]).
But for the great majority of people, recall is much less of a pictorial
nature than they believe -- see the experiment with the letter square. We
overestimate the precision of our imagery, as we overestimate the precision
of our verbal thinking; quite often we think that we know exactly what we
want to say, but ah, when it comes to putting it on paper! We are unaware
of the blurs and gaps in our verbal thinking, as we are unaware of the
missing detail, the empty spaces between the visual schemata.
Learning by Rote
The dullest sort of memory, which I have not mentioned so far, consists
of word-sequences which have been learned by rote. But even here we find
hicrarchic order. The items memorised are not single elementary bits,
but larger holons which tend to form patterns. A poem learned by heart
is given coherence by patterns of rhyme, rhythm, syntax and meaning,
superimposed on each other on the colour-print principle. The job of
memorising is thus reduced to fitting the patterns together and filling in
the gaps they leave. The same applies to learning a piano sonata, where
the structure of the musical holons -- the architecture of movements,
of themes and variations, development and recapitulation, rhythm and
harmony -- is equally obvious. Where the data to be stored show no
apparent cohesion, as in the case of memorising the dates of battles
and reigns, or a string of nonsense syllables, all sorts of mnemonic
devices or jingles will be invented to provide some structural pattern.
Thus even rote-learning is never purely mechanical. A certain amount
of 'stamping in' by repetition is often indispensable to provide
cohesion. How much 'stamping in' is needed depends on the meaningfulness
of the task, and on the subject's capacity for comprehending it. At one
extreme there is the dog in the Pavlovian laboratory, who needs days or
weeks of monotonously repeated experiences to cotton on to the fact that
the figure of an ellipse shown on a cardboard signals food, but a circle
does not. No wonder -- for outside the laboratory, food is not signalled
by ellipses on cardboards, and the dog's perceptual hierarchies are not
attuned to treating them as relevant events. Similar considerations apply
to Thorndike's cats in puzzle-boxes and Skinner's pigeons. They are all
given tasks to learn for which they lack the native equipment, and which
they can only learn by 'stamping in'. To proclaim this procedure to be
the paradigm of human learning was one of the grotesque aberrations of
flat-earth psychology.*
* For a more detailed discussion, see The Act of Creation,
Book Two, Chapter XII.
Gestalt theorists, on the other hand, are inclined to equally
extreme views of the opposite kind. They would maintain that true
insightful learning excludes all trial and error and is based on a
total understanding of the 'total situation'. In the present theory,
insight and understanding are regarded as matters of degree, and not,
as the Gestalt school holds, an all-or-nothing affair. Insight depends
on the multi-dimensional analysis of the input in its various aspects, on
extracting relevant messages from irrelevant noise, identifying patterns
in the mosaic until it has become saturated, as it were, with meaning.
To sum up: we must assume the existence of multiple, interlocking
hierarchies of perception which provide the multi-dimensionality or
multi-colouration of experience. In the process of storing memories
each hierarchy strips down the input to bare essentials, according to
its own criteria of significance.
Recalling
the experience requires dressing it up again. This is
made possible, up to a point, by the co-operation of the hierarchies
concerned, each of which contributes those factors which it has deemed
worth preserving. The process is comparable to the superimposition
of colour-plates in printing -- or of the wallpaper-maker's several
stencils. Added to this are touches of 'vivid detail', perhaps fragments
of eidetic imagery, which carry a strong emotive charge -- and the result
is a kind of collage, with glass eyes and a strand of genuine hair stuck
onto the hazy schematised figure.
It may also happen that fragments of different origin are mistakenly
incorporated into the collage included in the recall of experiences
to which they do not belong. For memory is a vast archive of abstracts
and curios, which are all the time being rearranged and revalued by the
archivist; the past is constantly being re-made by the present. But most
of the making and remaking is not consciously experienced. The canons
of perception and memory operate instantaneously and unconsciously;
we are always playing games without awareness of the rules.
VII
THE HELMSMAN
The human being is the highest self-regulating system.
Ivan Petrovich Pavlov
I have used the terms 'interlocking' or 'interlacing' hierarchies. Of
course hierarchies do not operate in a vacuum. The liver is part of
the digestive, the heart of the circulatory, system; but the heart
is dependent on the glucose which the liver provides, and the liver
depends on the correct functioning of the heart. This truism of the
inter-dependence of the various processes in an organism is probably
the main cause of the confusion which has obscured from view its
hierarchic structure. It is as if the sight of the foliage of entwined
branches in a dense forest made us forget that the branches originate
in separate trees. The trees are vertical structures. The meeting
points of branches from neighbouring trees form horizontal networks
at several levels. Without the trees there could be no entwining, and
no network. Without the network each tree would be isolated and there
would be no integration of functions. Arborisation and reticulation
(from
reticulum
= net) seem to be complementary principles in the
architecture of organisms.
To get a possible misunderstanding out of the way, I must insert here
a rather obvious remark. A forest consists of a multitude of trees. A
living orgasm is an integrated whole -- a single tree. And yet I
have been talking of perceptual and motor hierarchies as if they were
separate entities. In fact, of course, they are merely main branches
on the same tree, or 'sub-hierarchies'. But to call them that would
be unnecessarily pedantic, as each branch of a hierarchy is itself
hierarchically structured. Thus it is often convenient to regard the
Foreign Office and the War Office as separate hierarchies, although they
are branches of Government joined at Cabinet level.
Sensory-Motor Routines
The most obvious example of interlocking hierarchies is the sensory-motor
system. The sensory hierarchy processes 'information' and transmits it in
a steady flow to the conscious ego at the apex; the ego makes decisions
which are spelled out by the downward stream of impulses in the motor
hierarchy. But the apex is not the only point of contact between the
two systems; they are connected by entwining 'networks' on various levels.
The network on the lowest level consists of so-called local reflexes.
They are short-cuts between the ascending and descending flow, like
loops connecting the opposite traffic streams on a motor highway:
routine reactions to routine types of stimuli, like the knee-jerk,
which do not require the intervention of higher mental processes. The
level to which decision-making is referred depends on the complexity of
the situation. The knee-jerk, or the blink-reflex, is usually completed
before the stimulus has reached awareness.
One of the fundamental errors of the crude Watsonian brand of Behaviourism
was the assumption that complex activities result from the summation
of isolated local reflexes. We now know that the opposite is true, that
local reflexes are the last to make their appearance in the development
of the nervous system in the embryo: 'Behaviour develops in man . . . by
the expansion of a total pattern that is integrated as a whole from the
beginning, and by individuation of partial patterns (reflexes) within
the unitary whole' (Coghill [1]). Moreover, reflexes are influenced by
higher levels of the hierarchy: even the knee-reflex goes haywire if
the patient knows what the doctor is up to. Human behaviour is not a
succession of knee-jerks and eye-blinks, and any attempt to reduce it
to these terms leads again to flat-earth psychology.