The Act of Creation (80 page)

Chapter X
). Caterpillars belong to the natural
environment of the chick; the perception of the striped creature is
a biologically relevant input while the chick is engaged in pecking;
its horrid taste makes it even more relevant; the visual input will
accordingly be allowed to pass through the filters of the memory
hierarchy, where it will be encoded and serve as an analyser-device for
future inputs. On the other hand, gongs, bells, metronomes, tuning forks,
cardboard figures, red lights, and electric shocks have no biological
relevance to the species dog, nor to the individual dog outside the
laboratory. In its natural environment the dog would pay no attention to
them, but pursue some exciting scent; the cardboard ellipse would never
have a chance to form a stable trace in the dog's perceptual organization.

 

 

How should one explain, then, that the experimenter nevertheless
succeeds in stamping in the response? In the first place, a Pavlov dog
in its restraining harness is not a dog, but a preparation, which can
only be found "in laboratorio". It is immobilized on the experimental
platform, in a soundproof laboratory, alone, cut off from all natural
stimuli and habitual activities; it is, so to speak, isolated under
a glass bell. This state creates a particular stress in the animal,
called the dog's 'laboratory attitude', which is sharply distinguished
from its behaviour outside the lab. Deprived of all other stimuli and
activities, the ticking of the metronome or the figure on the cardboard
are the only events on which the dog's attention can focus; there is no
competition between different inputs; and thus the originally irrelevant
stimuli are gradually transformed into relevant stimuli and encoded in
stable traces. Relevant to what? To the only biologically important
events which are allowed to occur under the glass bell: the periodic
appearance of meat-powder by remote control. The dog's laboratory
attitude is dominated by this periodically repeated event; and as
his perceptual hierarchy becomes slowly readapted to pay attention,
in the absence of other stimuli, to the irrelevant sound of the bell,
the nascent trace of the bell-sound will become incorporated into the
feeding hierarchy. If the sound of the bell always overlaps with the
appearance of the meat-powder, then the sound will eventually trigger off
the feeding code, as the first two bars of the Marseillaise will trigger
off the following bars; the dog will begin to salivate. But salivation
is merely the first, anticipatory act of its feeding behaviour, and if
no meat-powder is actually presented, it will stop there; the dog will
not chew and snap at nothing. In the absence of food, the feeding habit
gets no 'environmental feedback', and the activity comes to a halt at
the expectant, salivatory stage. It is quite untrue, therefore, to say
that the 'conditioned stimulus', e.g. the bell, has been 'substituted'
for the 'unconditioned stimulus', the meat-powder. What happened was that
the dog has learned, by the cumulative effect of its past experience, to
expect
the appearance of the meat-powder after the bell, because
that is the 'rule of the game'. He salivates,
not
because he
confuses the bell with food, but because he expects the food, signalled
by the bell. We can say, with Polànyi [19], that the dog has
arrived at a correct empirical induction; or with Craik, that the dog's
nervous system is now functioning 'as a calculating machine capable of
modelling or parallelling external events' which is 'the basic feature of
thought and of explanation' [20]; or in our own terms, that the invariant
factor in a repeated sequence or experiences has been encoded in the
dog's brain.

 

 

All this is a far cry from the conception of reflex arcs in which USs,
CSs, URs, and CRs are mechanically coupled together or substituted
for each other like railway carriages in a shunting yard. In fact, the
dog's behaviour in the strange, artificial universe where red lights
portend food and metronomes electric shocks, is eminently 'logical';
and the reason why it takes so long to stamp in the lesson is that
the dog must readapt its entire attitude and hierarchy of values --
of what is important in life and what is not -- to that universe, where
natural law is replaced by Pavlov's law; a kind of Nietzschean "Umwertung
aller Werte". Perhaps the highest achievement of the dog is learning
to discriminate between more or less flattened ellipses -- for unlike
its sharp pitch-discrimination, based on native equipment, geometrical
forms must represent the height of irrelevance in canine eyes. Yet once
relevance has been revalued, and the perceptual analyser-devices have been
established, the development of sharper sub-analysers or discriminatory
filters must follow the stages outlined in
Chapter X
.*

 

 

In a seemingly casual aside, Hebb has remarked that 'the characteristic
adult learning (outside of psychological laboratories) is learning that
takes place in a few trials, or in one only'. [21] The implication
is that the stamping-in of responses under artificial conditions in
dogs, cats, or rats is quite uncharacteristic of the normal learning
process. To try to base a human psychology on these procedures was a
rather perverse approach.

 

 

 

Do Insects have Insight?

 

 

The work of Baerends, de Kruyt, Tinbergen, and Thorpe was rarely mentioned
in the controversies to which I have referred, as if wasps, bees, fishes,
and birds belonged to the fauna of another planet. As Thorpe remarked
wistfully: 'Perhaps the arguments as to whether certain performances'
of rats in mazes represent insight or trial-and-error learning would
have been somewhat less prolonged if the abilities of some of the "lower
animals", such as insects, had been known. . . . While it surprises no
one that something like latent learning should be displayed by mammals
and by birds with their proverbial powers of orientation, it may come
as something of a shock to comparative psychologists who work primarily
with mammals to find learning of this kind displayed at a high level
among invertebrates. It is true that, with the confirmation of the work
of von Frisch on the orientation of the hive-bee, we are now prepared to
believe almost anything of bees, but there are certainly many insects
other than bees, and many invertebrates other than insects, in which
latent learning and similar performances can be discerned. The neglect
of the study of invertebrate behaviour has given the impression that
insight-learning is a characteristically human faculty hardly to be
expected in a sub-primate mammal and, of course, out of the question in
an arthropod. We now see what an astonishing misconception this is.' [22]

 

 

While behaviourists denied the rat the capability to acquire a mental
map of a maze, the ethologists have shown that this is precisely what
insects do. Their work merits consideration in some detail -- which is
done best by textual quotation. Tinbergen and de Kruyt have trained wasps
to find their way to the nest by a configuration of certain landmarks
(such as fir-cones and twigs). When these training marks were moved,
and the wasp might have been expected to show complete disorientation, it
'will suddenly utilize new landmarks completely unrelated to the previous
orientation marks on which it had apparently been trained -- a result
which has interesting and suggestive similarity to Krechevsky's work on
hypotheses in maze-learning. Many such examples lead us imperceptibly to
what we may consider as insight-learning. Ammophila hunts caterpillars
which are too heavy to be brought back on the wing, and which may thus
have to be dragged for a hundred yards or more across and through every
imaginable natural obstacle. Here the original learning of the territory
has probably been in the main affected by observation from the air,
and yet the return has to be made on foot. Although the insect may
from time to time leave her prey and take short survey flights, this
is by no means invariable . . . and quite often the wasp seems able to
maintain orientation while on the ground as a result of earlier aerial
reconnaissance.' [23] When large obstacles (metal screens 50 by 120
centimetres) were placed in its path, 'the insect diverged just enough
to carry it round the obstacle on a perfectly smooth, even course of
maximum economy of effort. On one particular occasion the experiment
was immediately repeated twice with the same results, but the third time
the insect walked straight at the screen, climbed with perfect ease to
the top and, without ever letting go of its caterpillar, flew down to
the ground on the other side and continued its journey. On subsequent
occasions this insect would adopt now one type of behaviour, now another,
but in no instance did she ever show trial and error. The solution to
the problem was always smooth, unhesitating, and economical.

 

This and other individuals which behaved in the same way were then
caught and transported in a dark box to a new site, a process taking
less than a minute. On release the insect might have been expected to
be at least momentarily disorientated. On the contrary, it appeared
quite unperturbed and without any orientation flight set out at once
on its new course. It was again given the detour test three times on
its new course, but it reacted as efficiently as before and within a
few minutes had arrived exactly on its nest. Although the insect too,
on occasion, shows some evidence of disorientation, nevertheless the
overwhelming impression given (as also recorded by Baerends (1941) and
other workers) was one of almost uncanny knowledge of the details of the
terrain.' [24]  Thorpe concludes: 'In some instances it is possible that
the homing faculty depends on no more elaborate sensory mechanism than
that involved in simple taxes or light-compass reactions. Nevertheless,
it is certain that in a large number of examples this is inadequate
and that we have a true place memory. [25]

 

In the case of at least the honey-bee, the memory is communicable. The
orientation dance of the bee is certainly as striking an example as one
could wish for, of place-learning encoded and re-coded into a symbolic
motor-pattern. Yet again the question arises: if, following Thorpe,
we call the behaviour of these insects 'insightful', have we not
stretched the word into a kind of rubber concept? And once more the
only description which implies neither too much nor too little seems
to be that the organism has contrived to build a coded model of the
invariant and significant aspects of the territorial environment into
its nervous system.

 

 

 

The Controversial Rat

 

 

Munn's
Handbook of Psychological Research on the Rat
, published in
1950, contains a bibliographical list of over two thousand five hundred
titles; its rate of growth since then is anybody's guess. A considerable
portion of this research was devoted to maze studies. Not even Newton,
as Bertrand Russell remarked [26], could learn a maze by any method
other than trial and error; yet what the rat learns is not a chain
of responses, but the pattern of the maze as a whole -- as shown by
the experiments with mutilated rats, and in others where the rat takes
prompt advantage of short-cuts when a wall is removed, and avoids newly
created cul-de-sacs. The evidence is equally conclusive that the rat is
capable of latent learning and of forming 'hypotheses' by 'provisional
tries'. Yet the Great Rat Controversy was kept going -- partly because
S.-R. theorists kept coming up with ingenious alternative interpretations
of the evidence, and partly because of the weighted character of much of
the experimental procedure itself. A good illustration for this was the
'continuity versus non-continuity' dispute, where Spence and others
represented the behaviourist view against Krech, Lashley, etc. The
results could be interpreted either or neither way; but -- as Osgood
wrote, in summing up the controversy: 'It is significant with respect
to methodology in psychological experimentation that, almost without
exception, the studies supporting the Lashley view have used the jumping
stand, while those supporting the continuity view have used a Yerkes-type
discrimination box.' [27]

 

 

Not only the experimental conditions, but the experimenters' subjective
attitudes seemed to exert their influence on the data obtained. In
this respect Rosenthal's 'experiment on experimenters' must have come
as a shock to students who had taken at least the 'hard and fast'
quantitative data (if not the interpretations) of nearly half a century
of rat experiments for granted. Rosenthal gave one group of his research
workers rats which, he explained, were 'geniuses' specially bred from a
stock with exceptionally good maze-learning records. To a second group
of researchers he gave what he explained were 'stupid rats'. In fact,
all rats were of the same common-or-garden breed; yet the score-sheets
of the 'genius rats' showed unmistakably that they learned to run the
maze much faster than the 'stupid rats'. [28] The only explanation
Rosenthal could offer was that the bias in the research-workers' minds
had somehow been transmitted to the rats -- just how this was done he
confessed not to know. These and other experiments by Rosenthal caused
one science editor to comment: 'The results throw a pall over the entire
range of psychological tests as reported by the psychologists over the
last fifty years.' [29]

 

 

Thus I shall have little more to say about the bar-pressing and
maze-running experiments with rats. In spite of the impressive
mathematical apparatus, and the painstaking measurements of 'rates of
response', 'habit-strength', 'fractional anticipatory goal-responses',
and the rest, rarely in the history of science has a more ambitious
theory been built on shakier foundations.