THE SCIENTIFIC IMAGINATION
Psychology, or the science of mental life as revealed in behavior, has
been greatly indebted to physiologists and to students of medicine in
general. Any attempt to catalogue the names of those who have approached
the study of the mind from the direction of the natural sciences is
liable to prove unsatisfactory, and a brief list is sure to entail many
important omissions. The mention of Locke, Cheselden, Hartley, Cabanis,
Young, Weber, Gall, Müller, Du Bois-Reymond, Bell, Magendie, Helmholtz,
Darwin, Lotze, Ferrier, Goltz, Munk, Mosso, Maudsley, Carpenter, Galton,
Hering, Clouston, James, Janet, Kraepelin, Flechsig, and Wundt will,
however, serve to remind us of the richness of the contribution of the
natural sciences to the so-called mental science. Indeed, physiology
would be incomplete unless it took account of the functions of the sense
organs, of the sensory and motor nerves, of the brain with its
association areas, as well as the expression of the emotions, and the
changes of function accompanying the development of the nervous system,
from the formation of the embryo till physical dissolution, and from
species of the simplest to those of the most complex organization.
At the beginning of the nineteenth century the French physician Cabanis
was disposed to identify human personality with mere nervous
organization reacting to physical impressions, and to look upon the
brain as the organ for the production of mind. He soon, however,
withdrew from this extreme position and expressed his conviction of the
existence of an immortal spirit apart from the body. One might say that
the brain is the instrument through which the mind manifests itself
rather than the organ by which mind is excreted. Even so, it must be
agreed that the relation between the psychic agent and the physical
instrument is so close that physiology must take heed of mental
phenomena and that psychology must not ignore the physical concomitants
of mental processes. Hence arises a new branch of natural science,
physiological psychology, or, as Fechner (1860), the disciple of Weber,
called it, psycho-physics.
Through this alliance between the study of the mind and the study of
bodily functions the intelligence of the lower animals and its survival
value, the mental growth of the child, mental deterioration in age and
disease, and the psychological endowments of special classes or of
individuals, became subjects for investigation. Now human psychology is
recognized as contributing to various branches of anthropology, or the
general study of man.
Wilhelm Wundt, who, as already implied, had approached the study of the
mind from the side of the natural sciences, established in 1875 at the
University of Leipzig the first psycho-physical institute for the
experimental study of mental phenomena. His express purpose was to
analyze the content of consciousness into its elements, to examine these
elements in their qualitative and quantitative differences, and to
determine with precision the conditions of their existence and
succession. Thus science after contemplating a wide range of outer
phenomena--plants, animals, earth's crust, heavenly bodies, molecules
and atoms--turns its attention with keen scrutiny inward on the thinking
mind, the subjective process by which man becomes cognizant of all
objective things.
The need of expert study of the human mind as the instrument of
scientific discovery might have been inferred from the fact that the
physicist Tyndall read before the British Association in 1870 a paper on
the Scientific Use of the Imagination, in which he spoke of the
imagination as the architect of physical theory, cited Newton, Dalton,
Davy, and Faraday as affording examples of the just use of this creative
power of the mind, and quoted a distinguished chemist as identifying the
mental process of scientific discovery with that of artistic production.
Tyndall even chased the psychologists in their own field and stated that
it was only by the exercise of the imagination that we could ascribe the
possession of mental powers to our fellow creatures. "You believe that
in society you are surrounded by reasonable beings like yourself....
What is your warrant for this conviction? Simply and solely this: your
fellow-creatures behave as if they were reasonable."
On the traces of this brilliant incursion of the natural philosopher
into the realm of mental science, later psychologists must follow but
haltingly. Just as in the history of physics a long series of studies
intervened between Bacon's hypothesis that heat is a kind of motion
(1620) and Tyndall's own work, _Heat as a Mode of Motion_ (1863), so
must many psychological investigations be made before an adequate
psychology of scientific discovery can be formulated. It may ultimately
prove that the passages in which Tyndall and other scientists speak of
scientific _imagination_ would read as well if for this term, intuition,
inspiration, unconscious cerebration, or even reason were substituted.
At first glance it would seem that the study of the sensory elements of
consciousness, motor, tactile, visual, auditory, olfactory, gustatory,
thermal, internal, pursued for the last half century by the experimental
method, would furnish a clue to the nature of the imagination. A visual
image, or mental picture, is popularly taken as characteristic of the
imaginative process. In fact, the distinguished psychologist William
James devotes the whole of his interesting chapter on the imagination to
the discussion of different types of imagery. The sensory elements of
consciousness are involved, however, in perception, memory, volition,
reason, and sentiment, as they are in imagination. They have been
recognized as fundamental from antiquity. Nothing is in the intellect
which was not previously in the senses. To be out of one's senses is to
lack the purposive guidance of the intelligence.
The psychology of individuals and groups shows startling differences in
the kind and vividness of imagery. Many cases are on record where the
mental life is almost exclusively in visual, in auditory, or in motor
terms. One student learns a foreign language by writing out every word
and sentence; another is wholly dependent on hearing them spoken; a
third can recall the printed page with an almost photographic
vividness. The history of literature and art furnishes us with
illustrations of remarkable powers of visualization. Blake and Fromentin
were able to reproduce in pictures scenes long retained in memory. The
latter recognized that his painting was not an exact reproduction of
what he had seen, but that it was none the less artistic because of the
selective influence that his mind had exerted on the memory image.
Wordsworth at times postponed the description of a scene that appealed
to his poetic fancy with the express purpose of blurring the outlines,
but enhancing the personal factor. Goethe had the power to call up at
will the form of a flower, to make it change from one color to another
and to unfold before his mind's eye. Professor Dilthey has collected
many other records of the hallucinatory clearness of the visual imagery
of literary artists.
On the other hand, Galton, after his classical study of mental imagery
(1883), stated that scientific men, as a class, have feeble powers of
visual representation. He had appealed for evidence of visual recall to
distinguished scientists because he thought them more capable than
others of accurately stating the results of their introspection. He had
recourse not only to English but to foreign scientists, including
members of the French Institute. "To my astonishment," he writes, "I
found that the great majority of men of science to whom I first applied
protested that mental imagery was unknown to them, and they looked on me
as fanciful and fantastic in supposing that the words 'mental imagery'
really expressed what I believed everybody supposed them to mean. They
had no more notion of its true nature than a color-blind man, who has
not discerned his defect, has of the nature of color." One scientist
confessed that it was only by a figure of speech that he could describe
his recollection of a scene as a mental image to be perceived with the
mind's eye.
When Galton questioned persons whom he met in general society he found
"an entirely different disposition to prevail. Many men and a yet larger
number of women, and many boys and girls, declared that they habitually
saw mental imagery, and that it was perfectly distinct to them and full
of color." The evidence of this difference between the psychology of the
average distinguished scientist and the average member of general
society was greatly strengthened upon cross-examination. Galton
attributed the difference to the scientist's "habits of highly
generalized and abstract thought, especially when the steps of reasoning
are carried on by words [employed] as symbols."
It is only by the use of words as symbols that scientific thought is
possible. It is through coöperation in work that mankind has imposed its
will upon the creation, and coöperation could not have been carried far
without the development of language as a means of communication. Were it
not for the help of words we should be dependent, like the lower
animals, on the fleeting images of things. We should be bound to the
world of sense and not have range in the world of ideas. Words are a
free medium for thought, for the very reason that they are capable of
shifting their meaning and taking on greater extension or intension. For
example, we may say that the apple falls because it is heavy, or we may
substitute synonymous phraseology that helps us to view the falling
apple in its universal aspects. The mind acquires through language a
field of activity independent of the objective world. We have seen in an
earlier chapter that geometry developed as a science is becoming
gradually weaned from the art of surveying. Triangles and rectangles
cease to suggest meadows, or vineyards, or any definite imagery of that
sort, and are discussed in their abstract relationship. Science demands
the conceptual rather than the merely sensory. The invisible real world
of atoms and corpuscles has its beginning in the reason, the word. To
formulate new truths in the world of ideas is the prerogative of minds
gifted with exceptional reason.
To be sure, language itself may be regarded as imagery. Some persons
visualize every word spoken as though it were seen on the printed page;
others cannot recall a literary passage without motor imagery of the
speech organs or even incipient speech; while others again experience
motor imagery of the writing hand. With many, in all forms of
word-consciousness, the auditory image is predominant. In the sense of
being accompanied by imagery all thinking is imaginative. But it is the
use of words that permits us to escape most completely from the more
primitive forms of intelligence. So directly does the printed word
convey its meaning to the trained mind that to regard it as so much
black on white rather than as a symbol is a rare and rather upsetting
mental experience. Words differ among themselves in their power to
suggest images of the thing symbolized. The word "existence" is less
image-producing than "flower," and "flower" than "red rose." It is
characteristic of the language of science to substitute the abstract or
general expression for the concrete and picturesque.
When, therefore, we are told that the imagination has been at the bottom
of all great scientific discoveries, that the discovery of law is the
peculiar function of the creative imagination, and that all great
scientists have, in a certain sense, been great artists, we are
confronted with a paradox. In what department of thought is imagination
more strictly subordinated than in science? Genetic psychology attempts
to trace the development of mind as a means of adjustment. It examines
the instincts that serve so wonderfully the survival of various species
of insects. It studies the more easily modified instinct of birds, and
notes their ability to make intelligent choice on the basis of
experience. Does the bird's ability to recognize imply the possession of
memory, or imagery? Increased intelligence assures perpetuation of other
species in novel and unforeseen conditions. The more tenacious the
memory, the richer the supply of images, the greater the powers of
adaptation and survival. We know something concerning the motor memory
of rodents and horses, and its biological value. The child inherits less
definitely organized instincts, but greater plasticity, than the lower
animals. Its mental life is a chaos of images. It is the work of
education to discipline as well as to nourish the senses, to teach form
as well as color, to impart the clarifying sense of number, weight, and
measurement, to help distinguish between the dream and the reality, to
teach language, the treasure-house of our traditional wisdom, and logic,
so closely related to the right use of language. The facts of abnormal,
as well as those of animal and child psychology, prove that the
subordination of the imagination and fancy to reason and understanding
is an essential factor in intellectual development.
No one, of course, will claim that the mental activity of the scientific
discoverer is wholly unlike that of any other class of man; but it leads
only to confusion to seek to identify processes so unlike as scientific
generalization and artistic production. The artist's purpose is the
conveyance of a mood. The author of _Macbeth_ employs every device to
impart to the auditor the sense of blood-guiltiness; every lurid scene,
every somber phrase, serves to enhance the sentiment. A certain picture
by Dürer, a certain poem of Browning's, convey in every detail the
feeling of dauntless resolution. Again, a landscape painter, recognizing
that his satisfaction in a certain scene depends upon a stretch of blue
water with a yellow strand and old-gold foliage, proceeds to rearrange
nature for the benefit of the mood he desires to enliven and perpetuate.
It is surely a far cry from the attitude of these artists manipulating
impressions in order to impart to others an individual mood, to that of
the scientific discoverer formulating a law valid for all intellects.
In the psychology of the present day there is much that is reminiscent
of the biological psychology of Aristotle. From the primitive or
nutrient soul which has to do with the vital functions of growth and
reproduction, is developed the sentient soul, concerned with movement
and sensibility. Finally emerges the intellectual and reasoning soul.
These three parts are not mutually exclusive, but the lower foreshadow
the higher and are subsumed in it. Aristotle, however, interpreted the
lower by the higher and not vice versa. It is no compliment to the
scientific discoverer to say that his loftiest intellectual achievement
is closely akin to fiction, or is the result of a mere brooding on
facts, or is accompanied by emotional excitement, or is the work of
blind instinct.
It will be found that scientific discovery, while predominantly an
intellectual process, varies with the nature of the phenomena of the
different sciences and the individual mental differences of the
discoverers. As stated at the outset the psychology of scientific
discovery must be the subject of prolonged investigation, but some data
are already available. One great mathematician, Poincaré, attributes his
discoveries to intuition. The essential idea comes with a sense of
illumination. It is characterized by suddenness, conciseness, and
immediate certainty. It may come unheralded, as he is crossing the
street, walking on the cliffs, or stepping into a carriage. There may
have intervened a considerable period of time free from conscious effort
on the special question involved in the discovery. Poincaré is inclined
to account for these sudden solutions of theoretical difficulties on the
assumption of long periods of previous unconscious work.
There are many such records from men of genius. At the moment the
inventor obtains the solution of his problem his mind may seem to be
least engaged with it. The long-sought-for idea comes like an
inspiration, something freely imparted rather than voluntarily acquired.
No mental process is more worthy to command respect; but it may not lie
beyond the possibility of explanation. Like ethical insight, or
spiritual illumination, the scientific idea comes to those who have
striven for it. The door may open after we have ceased to knock, or the
response come when we have forgotten that we sent in a call; but the
discovery comes only after conscious work. The whole history of science
shows that it is to the worker that the inspiration comes, and that new
ideas develop from old ideas.
It may detract still further from the mysteriousness of the
discovery-process to add that the illuminating idea may come in the
midst of conscious work, and that then also it may appear as a sudden
gift rather than the legitimate outcome of mental effort. The
spontaneity of wit may afford another clue to the mystery of scientific
discovery. The utterer of a witticism is frequently as much surprised by
it as the auditors, probably because the idea comes as verbal imagery,
and the full realization of their significance is grasped only with the
actual utterance of the words. The fact that to the scientific
discoverer the solution of his problem arrives at the moment when it is
least sought is analogous to the common experience that the effort to
recall a name may inhibit the natural association.
The tendency to emphasize unduly the rôle played by the scientific
imagination springs probably from the misconception that the imagination
is a psychological superfluity, one of the luxuries of the mental life,
which should not be withheld from those who deserve the best. The view
lingers with regard to the æsthetic imagination. James could not
understand the biological function of the æsthetic faculty. On the
alleged uselessness of this phase of the human mind A. J. Balfour has
recently based an argument for the immortality of the soul. This view is
strikingly at variance with that which inclines to identify it with that
mental process which creates scientific theories and thus paves the way
for the adjustment of posterity to earthly conditions.
REFERENCES
Baldwin, J. M., _History of Psychology_, 1913. 2 vols.
Dessoir, Max, _Outlines of the History of Psychology_, 1912.
Klemm, Otto, _A History of Psychology_, 1914.
Merz, J. T., _History of European Thought in the Nineteenth Century_,
vol. II, chap. XII, On the Psycho-physical View of Nature.
Rand, Benjamin, _The Classical Psychologists_, 1912.
Ribot, T. A., _English Psychology_, 1889.
Ribot, T. A., _German Psychology of To-day_, 1886.