Rationality and Intuition
in Judith Wechsler (ed) On Aesthetics in Sciences
Sir Geoffrey argues that all knowing is based on a form of conceptual architecture and depends, like other skillful doing, on the ability to impose, recognize, and combine forms. He distinguishes this mental capacity from the capacity for logical deduction and analysis and argues that it is underrated and even ignored only because of our unwillingness to admit the existence of mental activities which we cannot fully describe, a reluctance which is itself a product of recent Western culture. He follows this line of thought from the simplest forms of perception and cognition to deliberate physical and social design. - J.W.
Why not “aesthetics in science”? Whence comes the implication that to find aesthetics in science is like finding poetry in a timetable? The answer lies in the sad history of Western culture which, over the last two centuries, has so narrowed the concepts of both Science and Art as to leave them diminished and incommensurable rivals - the one an island in the sea of knowledge not certified as science; the other an island in the sea of skill not certified as Art.
This debasement is relatively new. In medieval universities all fields of knowledge open to organized study were scientiae, and all fields of skill open to organized acquisition were Arts. Rhetoric and astronomy were equally scientiae; but the title accorded to the student who satisfied his examiners in these and the other recognized scientiae was that of a Master of Arts. Similarly, Art was not separated from technology; there was an Art and Mystery of Bricklaying. Cellini made a splendid pair of front doors. Where was the boundary between art and architecture, mason, carver, builder, and architect?
Moreover the two words “Ars” and “Scientiae” not only embraced virtually all skill and knowledge, but also overlapped each other’s territory without offense. Everyone knew that knowing was a skilled activity, an Art. Both words connoted both product and process - on the one hand an accumulating store of knowledge and artifacts; on the other hand a growing heritage of transmitted skills and standards of skill and excellence in knowing and doing.
Science acquired its present limited meaning barely before the nineteenth century. It came to apply to a method of testing hypotheses about the natural world by observations or experiments which might give results inconsistent with the hypothesis to be tested. Thence it came to comprise the growing body of related hypotheses which had survived these tests. The method never explained wholly and often failed to explain at all how the hypothesis originally emerged. But this fact was not generally ac-
This paper is a greatly extended version of a lecture which I gave at the Massachusetts Institute of Technology in April, 1974. It embodies and expands parts of a longer unpublished paper called “The Tacit Norm,” prepared for a symposium on The Moral and Esthetic Structure of Human Adaptation held by the Wenner-Gren Foundation for Anthropological Research at Burg Wartenstein in July, 1969 on which I drew for the original lecture.
knowledged until this century. Even now it courts opposition to describe a scientific theory as a work of art, largely because of the corresponding narrowing of the concept of Art.
Yet few would deny that a scientific hypothesis, a technological invention, a plan for a new city, a painting, a musical composition, and a new law are all human artifacts, skillful making by human minds of designs for ordering or explaining some aspect of what we experience as reality. And few would deny that all such designing involves the creation, imposition, and recognition of form.
Equally, few would deny that particular achievements such as these are episodes in a process of change which proceeds continuously, though slowly and often unconsciously, for example, in the kind of explanation which scientific minds find acceptable, in the kind of methods by which technologists approach their problems, in the aesthetic idiom in which artists express themselves, and in the ethical standards which lead societies to change their laws and customs. History reveals in retrospect the presence of standards in all these fields which guide those who work in them and those who criticize their work and which are themselves changed both by the creations which they guide and by the controversies which they provoke.
I am not denying in the least that there are differences between the different fields in which these “arts” are practiced. Indeed, if I had space to pursue the theme, I would insist that these differences are much greater than are usually admitted either by scientists or by any of those who use the word “science” as a generic term. I would insist that different fields of possible knowledge (scientiae) admit such different kinds as well as degrees of knowledge that it is confusing to class as “science” even all those fields which aspire to the name. There are important differences between the natural sciences and the logical sciences which include all the branches of mathematics and symbolic logic. There are even more striking differences between the natural sciences and what Herbert Simon1 has called the sciences of the artificial, by which he means the fields of knowledge of which the subject matter is partly man-made. Virtually our whole environment, he insists, is partly artificial in this sense. Not only tools, machines, and buildings but also institutions, languages, and cultures are human artifacts. What “scientific” knowledge, he asks, is possible about a subject matter which might be other than it is?
I do not find his answer adequate, even on a
very limited definition of “science,” but I warmly approve of the distinction
which he draws. The regularities to be
found in the “artificial” world are different in origin, kind, and reliability
from those to be found in the natural world. The
notably a knowledge of human history which is open to us only because we ourselves are human.
I do not propose to pursue these differences here because I am concerned to explore the mental processes which are common to them all and especially the element connoted by the word aesthetics in the title to this book. My thesis is that the human mind has available to it at least two different modes of knowing and that it uses both in appropriate or inappropriate combinations in its endless efforts to understand the world in which it finds itself, including its fellow human beings and itself. One of these modes is more dependent on analysis, logical reasoning, calculation, and explicit description. The other is more dependent on synthesis and the recognition of pattern, context and the multiple possible relations of figure and ground. The first involves the abstraction and manipulation of elements, irrespective of the forms in which they are combined. The other involves the recognition or creation of form, irrespective of the elements which compose it. Both are normal aspects of the neocortical development which distinguishes man from his fellow mammals. Both are needed and both are used in most normal mental operations.
They are often referred to as rationality and intuition, and the names would serve as well as any other, were it not that a difference in the character and function of the two capacities has attached to intuition, in our contemporary culture, a load of mischievous and misleading connotation.
The main difference to which I refer is that a rational process is fully describable, whereas an intuitive process is not. Because our culture has somehow generated the unsupported and improbable belief that everything real must be fully describable, it is unwilling to acknowledge the existence of intuition; and where it cannot avoid doing so, it tends to confine it to the area where the creative process is least constrained and most in evidence - namely the narrow contemporary concept of Art - so much so that when this ubiquitous faculty appears in the practice of “science,” it is greeted as a strange incursion from a foreign field called “aesthetics.” But in my view this approach half accepts the cultural confusion which I wish to contest.
The theory of biological evolution is a convenient example. For a century before Darwin and Wallace the fact of biological evolution had been forcing itself into the consciousness of Western man. It was opposed by the strange belief, accepted for more than a thousand years, that each and every possible biological form had been specially created by a divine demiurge so obsessively creative that he could not leave any conceivable form unrealized. Lovejoy2 has documented, in fascinating detail, the history of this theory and its eventual decay.
The main agent in its decay was the discovery of the fossil record. Here in sufficiently exact chronological order was a sequence of biological forms which exhibited continuity and discontinuity through change with time. Eohippus was a far cry from the favorite contemporary racehorse, yet the development of one from the other was clear enough.
Why was it clear? Measurement played no significant part in these acts of recognition. They were exercises in the human capacity of appreciating, comparing, and contrasting form. They threw no light on how these developments took place or why some died out. That had to await a theory. But the apparent fact arrested human attention before there was a theory to explain it and provided the driving power to seek a theory. Without it there would have been no theory of evolution, for there would have been nothing to explain.
This intuitive sense of form entered also into
the theory, the exp1ication, no less than into the explicandum.
The theory of natural selection
implied a theory of particulate inheritance which did not exist in
Are we to identify
It is, of course, perfectly reasonable to mistrust a faculty which is not fully describable (even though we cannot do without it), since its obscurity makes it hard to verify. We should expect then that the main function of the rational process would be to critize and test so far as it can the products of the intuitive process. And this is, of course, precisely what it does, as the history of science so clearly shows. It can do so only in varying degrees and the less it can do so the more trust we have to repose in other tests by which we come to accept or to change the product of our intuition.
The history of the natural sciences is full of once accepted intuitions (such as the “ether”) which were later found to be unneces-
sary or wrong. Some of them held up the progress of science for centuries. Such was the intuitive belief that the paths of the planets must be circular. Some proved useful though wrong. Such was the original atomic theory. For two thousand years science proceeded on the unverified assumption that all material forms must be constructed of basic individual elements, capable of countless combinations but not themselves further divisible. Within a few years after the existence of atoms was first actually demonstrated, it was found that they lacked both the characteristics with which they had been credited. They were neither indivisible nor indestructible. Yet atomic theory, so far from receiving its death blow, took off into the new world of subatomic physics. One of the first dividends was an understanding of at least some of the forces which enabled atoms to combine, a fact predicated in the original theory, yet wholly inexplicable if atoms were, in fact, no more than elemental billiard balls.
I have therefore avoided so far as possible in this paper the use of the expression “science and aesthetics.” I have chosen instead to concentrate on the relation between rationality and intuition. This is, indeed, well exemplified in the recent development of physics and mathematics to which this book is largely directed. But it is not confined to that context. I regard the creation and appreciation of form by the human mind as an act of artistry, whether the artifact be a scientific theory, a machine, a sonata, a city plan, or a new design in human relations. And I believe and seek to show that in all these acts of artistry, intuition and rationality are always involved, usually in the roles of creator and critic.
In the next section I explore the basis for this dualism. We know something about the processes of perception, cognition, and recognition. We know that we come to recognize repetitions and regularities in the physical world long before we have any theories about why these should be. We know that unsupported toys fall from our cots before we know anything about the law of gravitation. We know the reliability or otherwise of mother’s behavior long before we know any psychology. Our knowledge is contextual before it extends to causality; and it grows in both dimensions half-independently. We learn to distinguish more subtly differentiated contexts, just as we learn to distinguish the operations of more generalized laws. And equally, we learn to envisage and create new contexts, just as we learn to detect new causal relations. The technological innovator is a creator of new contexts, just as the scientific innovator is a discoverer of new causal regularities often based on his discovery, or even creation, of new conceptual entities such as elements or particles. Synthesis and analysis, contextual and causal explanation are distinct though insepar-
able aspects of human mental process in all mental activities. It need cause us no surprise that they are equally manifest in physics and mathematics.
I stress the tacit nature of the standards which we develop to guide our intuitive processes because this has become a stumbling block to the “rational” understanding of “intuition,” an aspiration which is obviously not fully attainable if the two are complementary capacities of the human mind.
In a later section I examine a process of design where the imposition of form on experience is more conscious and more obvious. I seek to show that in this case also the choice between possible forms is not governed by criteria which are fully describable and for the same reason.
In a brief last section I summarize the epistemological conclusions to which these reflections lead. They may not yet be orthodox, but they are far more constant with the thinking of our time than they would have been even a decade ago.
According to the view put forward here, knowing and designing are not separate or even separable activities, since our whole schema for knowing is a design, a model of reality consciously and unconsciously made, and constantly revised. Moreover it is a selective model made in response to our concerns which alone determine what we regard as relevant enough to be worth modeling. The design produced by the natural and the logical sciences is more conditioned by independent variables which it cannot “redesign.” But it is a design for all that and a design that is intimately connected with the concerns that drive us to make it, concerns that notably include aesthetic satisfaction.
Professor Christopher Alexander, in his book Notes on the Synthesis of Form,4 says, in effect, that design does not consist in the realization of form but in the elimination of “misfit.” The designer approaches his task with a set of tacit criteria, which appear only when some specific design is found to be inconsistent with one of them. The norm is known only negatively, when it is infringed. For the state of “fit” we have no evidence, except the agreeable absence of misfit. We have scarcely even a vocabulary for it - how vague and how numerous are all the antitheses to pain! Alexander observes that this elusive quality of the norm has been noted in other fields also; he instances the difficulty experienced by doctors when they try to define “positive health,” and by psychiatrists when they try to define psychological normality. 5
I believe that Alexander’s insight is of great generality and importance, and I shall develop it in ways which go beyond his
statement and with which he might not agree. I shall postulate, as the basic fact in the organization of experience, the evolution of norms by which subsequent experience is ordered, and which are themselves developed by the activities that they mediate. I shall suggest that this evolution of norms is a fundamental form of learning; that it provides the criteria not only for ethics and aesthetics, but also for all forms of discrimination (including those used by the various sciences), and that the norms so developed are tacit by logical necessity.
Suppose, for example, that I say, “That is an ash tree.” If you ask why I think so, I can only reply, “Because it looks like one.” If you are not satisfied, we may approach the tree, examine its leaves and the character of its bark and its seeds, if it happens to be seeding. This analysis may or may not confirm my initial judgment but it played no part in making that judgment. The tree was too far away for me to see these details.
If I had said, “That is a beautiful ash tree,” you would have regarded my judgment as “aesthetic” and we might have discussed the basis for my judgment that the tree was beautiful. Did I, for example, mean merely that is was an exceptionally fine specimen of its kind? It is less common to class as an exercise of aesthetic judgment the ability to classify it correctly as an ash tree, irrespective of my emotional response to it. This, nonetheless, is the wide sense in which I am using the words “aesthetic” and “intuitive.” The recognition of form is an exercise of judgment made by reference to criteria which are not fully describable because of the subtle combination of relationships in which they reside and equally because of their dependence on context.
I use the word “norm” in an unusually wide sense, to cover the criterion for every judgment which classifies, whether it seems to involve a judgment of fact or of value. This distinction itself I regard as outmoded for more reasons than I shall have space to include. Professor Pitkin,6 in her book Wittgenstein and Justice, has shown that the many different forms in which this antithesis is expressed (the “is” and the “ought,” descriptive and normative, and soon) have very different meanings. I shall stress that the concern of a human mind is necessary to define any situation and perhaps necessary to define even what we call a fact, since a fact wholly irrelevant to any human concern would not be knowable.
The norms which are best understood scientifically are those which turn visual sensory input into perception. The child learns to recognize and to name, partly by being often exposed to the same stimuli, partly by its own inner activity of ordering its experience, and partly by the persuasion of other human beings, exhorting, encouraging, correcting. In some way not yet fully understood, his central nervous system develops readiness to group
together, attend to, and recognize aspects of his surround - faces, places, belongings, relations - which recur and are of interest to him and to organize his accumulating knowledge by classifying it in an increasing number of overlapping categories. 7
These “readinesses to classify” are commonly called schemata. The word “schema” is important for my purposes because it is the only accepted word in a class much wider than that in which it is commonly used. We clearly develop “readinesses to recognize” not only perceptual gestalten but also situations of great generality and complexity (such as illness and revolution) and concepts of great abstraction (such as entropy and the British constitution). We develop schemata, perceptual and conceptual, partly by being exposed to countless particular examples from which we abstract what they have in common for our purposes (as a doctor does in a hospital or a lawyer in the courts) and partly through the “open-endedness” of language, introducing us to abstractions which later examples make real (like a doctor with his textbook of physiology and a lawyer with his textbook of jurisprudence). It is commonly recognized that a combination of the two is the best way to develop those readinesses to recognize which it is the business of education to teach and of all ages to learn.
The duality of this process, though familiar to experience, has long been an offense to the Western scientific mind and has given rise to a long-drawn controversy whether the mind identifies the familiar by checking a list of characteristics which define its identity or recognizes it by fitting some kind of perceptual gestalt to some kind of mental template. Adherents of either view can find plenty of weaknesses in the other,8 but neither party, until recently, seems to have conceived the possibility that the brain might be capable of both processes and might use them in appropriate - or sometimes inappropriate - combinations. This, nonetheless, seems to be the fact. Brain scientists are much concerned with the neurological basis for this in the difference of function between the two hemispheres of the neocortex. I am not concerned with the problems of location which engage them, but I am intensely concerned with their finding that the human brain is indeed capable of what Dr. Galin 9 calls “two cognitive styles” of activity.
The child learns to see. So does the beneficiary of corneal grafting. So does the doctor learning to diagnose; the radiologist learning to read a radiograph; the stockbreeder and forester learning to distinguish a good specimen from a poor or sick one. So does the connoisseur of Chinese ceramics. All these people, later, can write books about the criteria they use, but they cannot express these fully in a rule which the inexperienced can apply. The future mas-
ter must make these schemata his own by frequent use; and these schemata are also criteria, instruments by which specific misfits are detected, though they themselves cannot be specified.
Professor Woodger10 instances the novice looking through a microscope for the first time. He has a visual experience, but he does not perceive anything because he has not yet built up the schemata by which to recognize the inhabitants of this elfin world. Cognition is the result, as well as the precursor, of recognition. G.H. Lewes 11 expressed this elegantly and generally as long ago as 1879, “… the new object presented to sense or the new idea presented to thought must also be soluble in old experience, be recognized as like them, otherwise it will be unperceived, uncomprehended.” (italics added)
Woodger has no use for the distinction between percepts and concepts. A percept is a concept. The link with the primary world of sensory experience is always tenuous and selective. A rabbit to an anatomist is a different bundle of abstractions from a rabbit to a cook - even if it be the same rabbit. Bruner, Goodnow, and Austin12 agree with him that in perception, no less than in the most abstract thinking, the categories we use are our own invention; the order which we discover is imposed by ourselves and validated by its practical convenience to ourselves.
This is not to say that there is no order to be discovered in the natural world; on the contrary, the confirmation of experiment by the scientist and the less rigorous confirmation of the ordinary man’s experience is taken as evidence that the order devised by the mind bears some valid relation to the order inherent in the “real world out there.” We have at least constructed in our heads a viable analogue. But its viability is measured not only by its conformity with other experience of our own. It must also be sufficiently shared to mediate communication with others. Radical innovations in thinking take time to percolate into other minds and until they have done so, they are impotent and precarious.
Further, the validity of our chosen “order” is measured also by its power to make our own experience acceptable to ourselves. For this it must be sufficiently concordant with the rest of our organizing concepts; and it must also create a world in which we can bear to live. Rokeach,13 referring to “belief systems” (which correspond closely to what I have called ‘appreciative systems”), writes, “Such systems... serve two opposing sets of functions. On the one hand, they are Everyman’s theory for understanding the world he lives in. On the other hand, they represent Everyman’s defense network, through which information is filtered in order to render harmless that which threatens his ego… a belief system seems to be constructed to serve both masters at once; to under-
stand the world in so far as possible and to defend against it in so far as necessary.” This defensive function is not necessarily pathologic, though it always has a cost.
Thus, the world of reflective consciousness-I will call it the appreciated world - in which each of us lives, is structured by readinesses to conceive things and relations in particular ways, readinesses which are developed in our brains by experience, including experience received through human communication. I will extend the word “schemata” to cover all such readinesses, since it is free from the normative implications of such words as “standard,” “criterion,” and “norm” itself. Nonetheless, such schemata do function as norms, standards, and criteria, even in the most purely factual acts of discrimination. Screening experience, they classify what “fits” and reject “misfits.” And they do so equally whether they define a state of affairs in my surround - “That is a bull,” or its implications for me – “That is a threat,” or a situation accepted by myself or others as requiring a particular response - ”That is an obligation.”14
I labor these familiar points because I want to rescue from their normal oblivion three facts which I believe to be highly important: First, facts are not data. They are mental artifacts, selected by human concerns and abstracted from experience by filtering through a screen of schemata. Second, this screen is necessarily tacit; we infer its nature only from observing its operations, but our inferences can never be complete or up to date. Third, the screen is itself a product of the process which it mediates and, though tacit, can be developed by deliberately exposing it to what we want to influence it. (This is the essence of education.)
These schemata do not exist in isolation. They develop within the multiple contexts of experience. I find it convenient to think of these contexts as ordered by a three-dimensional matrix. What we notice is selected by our concerns, and our concerns are excited by what we notice. I will call our concerns our “value system” and call our organized readinesses to notice our “reality system.”15 I think of these as forming two sides of the matrix. The third is, of course, the dimension of time. Our reality system can represent the future and the hypothetical, as well as the actual present, and our value system can both evoke and respond to such constructions. Our most familiar mismatch signals are generated by the comparison of our expectations with our fears and our aspirations-that is to say, by comparing the constructions of our reality system and our value system when both are extended into the future.
I use and offer this simply as a convenient mental model. We are handicapped by lack of a realistic model of how our brains actually work, but communication science, by combining what we know of analogue and digital processes, can already provide us with a much more adequate picture than was possible even a few years ago, as Professor MacKay has shown. 16
These schemata are systematically related; a change in one will involve some change in others and will be resisted in proportion to the extent of the change involved unless this resistance is offset by the perceived benefit promised by the change. The theory of biological evolution, for example, when first put forward, was perceived by some as a hugely liberating idea, by others as hugely threatening. Hence the intense controversy which it aroused among laymen as well as scientists.
The impact of change will also be affected by the ease with which the proposed change can be understood. Biological evolution, however acceptable or unacceptable, was widely understandable, at least in principle. The theory of relativity was not. This difference muted resistance in some quarters and increased it in others.
T. S. Kuhn17 in The Structure of Scientific Revolutions has drawn a distinction between the normal course by which scientific knowledge grows by accretion and the periodic crises which call for a new “paradigm.” He has pointed out that minds attuned to the “normal” course seldom initiate the paradigm shift, though they unconsciously prepare the way for it. He has also observed that the same process is to be seen in art. So long as art worked within the paradigm of representation, its achievements were indeed cumulative. It progressively learned new ways to represent three-dimensional scenes on two-dimensional space. A new paradigm set new standards - not higher standards for the same kind of excellence but standards related to a different kind of excellence.
In fact, even what Kuhn calls “normal” science does not proceed without minor shifts in “tacit norms.” The simplest piece of induction is not explicable or even describable in the way in which we can describe and demonstrate the most complex deductive process. Nonetheless, paradigm shifts are most dramatically visible in the development of individual scientists and individual artists when they occur suddenly and make a major difference. Consider, for example, the story of Kepler, transported with excitement at suddenly seeing in Tycho Brahe’s calculations what Tycho himself could not see - that they were consistent only with elliptical planetary paths, a concept banned from consideration by the authority of Aristotle. Most dramatic of all perhaps is the
story of Kekule, seeing in a dream or vision as he dozed before the fire the benzene ring in the form of a whirling fiery serpent eating its own tail.
Wertheimer18 claims that his discussions with Einstein showed how critical was the moment when it first occurred to Einstein to question the conventional concept of time. And although Miller 19 has criticized Wertheimer’s reconstruction of Einstein’s thought processes, his own well-documented account in this book of those processes, not only in Einstein but in other leading minds who pioneered the amazing subsequent development of quantum theory, provides even more abundant examples of their paradigm shifts. It also reveals how closely these shifts are related to the personality and experience of the particular scientist involved. “Making sense” of the world is, it seems, a highly individual activity, even where the subject matter of our enquiry is the apparently independent fields of the “natural” and the “logical” sciences. Why else should Heisenberg, fully at home in a nonvisualizable universe, call Niels Bohr’s mathematics “disgusting” as described by Professor Miller in his paper in this book?
Similar shifts are seen in the development of individual artists. The development of Picasso’s art, as of many others, in other media as well as painting, illustrates the self-generated shifts of paradigm which a creative mind can achieve. The breakthrough comes sometimes after a spell of inactivity either willed or imposed by the artist’s incapacity to produce. Sometimes it can be seen in retrospect as following a series of tentative struggles towards what, for the artist, was still a hidden goal. In either case, when it emerges it is unmistakable.
These dramatic shifts make visible with peculiar clarity the structure of tacit norms, previously taken for granted, which they assail and replace. I am equally concerned in this paper with the process by which a system of tacit norms changes gradually over time.
I will next examine an example of design of a different kind, the redesign of an urban environment. The effort is far more conscious. Nonetheless, the norms involved remain only half revealed both in the process by which the problem is, ultimately, defined and in the process by which one of many possible partial solutions is chosen. And the reciprocal effect of the effort on the norms by which it is guided, though not fully detectable even with the wisdom of hindsight, is no less important than in the example already examined.
Consider a problem of urban planning. Several criteria can be described in general terms. Buildings must have access to vehicular
and pedestrian traffic appropriate to the activities which they generate; and the two types of traffic must be sufficiently separated to preserve an acceptable level of safety. Noise, air pollution, and interference with light must be kept within acceptable thresholds. And so on. But what in each case is the level of the appropriate and the acceptable? The policymaker may allot target values in each case but he can be sure that, if he pitches them high enough to be unquestioned, some at least, will not be capable of being realized. He cannot even make an exhaustive list, until an actual plan begins to emerge, so that its actual effect can be envisaged in each of the dimensions of success. He must wait for the planner before he can clearly define the problem that he wants the planner to solve.
What of the planner? - in so far as his function can be separated. Each of the requirements which he has to satisfy (and which thus become his concerns) make relevant, as possibilities or limitations, features of the physical site; and these in turn suggest their relevance, for good and ill, to other requirements. Hypothetical solutions begin to shape themselves in his mind and in rough sketch plans; and these engender often unsuspected meanings as they intersect with the various requirements in which he is concerned or even suggest others with which he ought to be concerned. One cell after another in the matrix is activated by such intersections of concern and opportunity; and from each intersection streams of further activation resonate along all the dimensions of the matrix.
This exercise can easily lose itself in boundless complexity. The list of requirements and the facts relevant to each can be extended in number and time with no clear limit, and every extension multiplies their interactions with each other. Alexander, in the book already mentioned,20 makes some valuable suggestions for keeping these many-factored problems under control by identifying those variables which can be grouped together in relatively independent clusters. But in any but the simplest problem, it is, I believe, vain to hope for a solution which will produce for every requirement a “fit” which would have been regarded as acceptable when the exercise began. Any solution will have to deal with some requirements in a way which will become acceptable only in the light of what it will make possible in other dimensions of success or, alternatively, of what is then seen to be the cost of making it any better, when this cost is measured in terms of the limitations it would pose on satisfying other requirements. 21
The designer, then, like the scientist, is engaged in a synthetic exercise. He must produce a single design which will be judged by multiple criteria. Some of these reinforce each other; some conflict with each other; most compete with each other for scarce resources. All are affected in some degree by any change made in
the interest of one of them. The number of possible designs, even within given costs, is unlimited and unknowable, for it depends on possibilities of innovation which cannot be known before they have been made. The comparison of one with another can be made only when both have been worked out and even then depends on the relative value attached to disparate criteria within the framework of a single solution.
However great the number of possible designs, the number submitted to the policy maker is seldom more than one. The resources demanded by large-scale planning are too great to permit detailed alternatives. Hence enormous importance attaches to the rapid and often obscure process by which the basic lines of the proffered solution are chosen, for these soon generate many vested interests, valid as well as invalid. Not least of these is that its sponsors, having grown familiar with its implications, can more confidently exclude the possibilities of unwelcome surprise, which would lurk in any alternative, until it had reached the same degree of elaboration.
The successful designer chooses what proves to be a viable approach by a process which is much better than random and which seems sometimes to be guided by uncanny prescience. So does the technological inventor, the scientific discoverer, the successful policy maker in government and business, and those apparently ordinary mortals whose human relations are at once richer, more varied, and more orderly than those of their neighbors. I do not postulate any unknown mental function - or, at any rate, any more unknown than they all are-when I describe these gifted people as having (like the artist) unusual sensitivity to form. But in thus grouping them together, I do suggest that they have something in common in terms of cerebral organizing capacity. I have no doubt that this something is a specially happy combination of the “two cognitive styles” mentioned by Dr. Galin in the paper already referred to - the one logical, analytic, and explicit; the other (and, in these cases, the more important) contextual, synthetic, and tacit.
This tentative postulate seems to derive support from many sides. The capacity for sensory discrimination varies greatly between individuals. It is most easily charted in music because the sound patterns produced by musical instruments can be formally described,22 even when they are immensely complex, as in concerted orchestral passages. It is demonstrable that people differ, not merely through differences in training, in their ability to recognize, for example, variations on a theme. It seems reasonable to
suppose that this innate capacity for discriminating musical patterns sets limits both to musical interest and to musical achievement.
By discrimination in its most general sense I mean the ability to distinguish figure from ground, signal from noise. 23 It is the basic limitation of any information system. It is distributed between individuals not only unevenly but selectively. Those concerned with the study of gifted children distinguish at least four kinds of giftedness, each of which can be described as unusual power of discrimination. The most familiar are the intellectually gifted, who can be identified with some confidence by tests of ability to recognize logical, including mathematical, relations. Distinct from these are the inventive, whose ability for practical innovation can coexist with quite limited power to handle abstractions. The aesthetically gifted are again a class apart. They are often impractical and sometimes unintellectual; and their gift for appreciating sensory form is highly selective. Aesthetic appreciation of nature may be dissociated from the appreciation of the fine and applied arts; and within these last, sensitivity to one medium may not extend to others.
In the categories of conscious experience, these forms of giftedness cover a wide variety of gifts, but they are all mediated by the brain and central nervous system. They all involve discrimination, in some form, between figure and ground, signal and noise; and they all depend on tacit criteria developed by experience within the inherent limitations of the particular neural heritage.
Some students of human giftedness distinguish a fourth type - social giftedness. These are those who show unusual interest and ability in sensing, maintaining, and creating relations with other people. These gifts too would seem to depend on unusually high capacity for discrimination. Students of human dialogue can show that it involves each party in setting up an inner representation of the other, and that the level of dialogue depends not only on the accuracy and refinement of this model, but also on the attitude of each to his inner representation of the other. G.H. Mead insisted on the social importance of a variable which he described as the ability and willingness to take the generalized role of the other. Communication theory begins to make this concept more precise.
I have distinguished two functions which in practice are never wholly separated but which are, nonetheless, logically distinct as two reciprocating phases in a recurrent process of mental activity. One is the creative process, which presents for judgment a work responsive to many explicit and tacit criteria. The other is the appreciative process, which judges the work by the criteria, tacit as well as explicit, to which it appeals, and finds it good or wanting, better or worse than another. The two phases of the process may
alternate many times in the course of producing the work. The work may never be finished; in a sense it can never be finished, for it is part of an ongoing process. Even the individual works of an artist are part of his “work,” which ends only with his death, or when he has nothing more to say, and which continues even after that in the creative and appreciative minds which it quickens.
In the example last given, the form of the work was an urban design. An urban design may be viewed as a creation in any of the four fields in which we exercise judgment - scientific, technological, ethical, and aesthetic. It may be viewed as a work of art, appealing to aesthetic criteria, like a sculpture or a painting. It may be viewed as an invention, appealing to functional criteria of utility. It may be viewed as a social creation, appealing to criteria of social need and satisfaction. It may be viewed as an intellectual creation, an expression of abstract relations, like a scientific theory. Examples could be chosen which would more clearly emphasise any one of these aspects, rather than another. We may be right to distinguish sharply between these different kinds of knowing and their related criteria. Yet they have notable common features which are likely to correspond to common features in the working of the human brain or in the patterns which our culture imposes on it.
The common features I want to emphasize are the following:
1. The form is produced by the activity of a concerned mind structured by tacit norms as well as by explicit rules. This concerned mind abstracts for attention what I will call a situation, by which I mean a set of related facts relevant to its concern. Part of this situation is seen as not modifiable by the agent; I will call this the context. The rest of the situation is the area to which form is to be given. I will call it the field. 24
2. The form is specific. It is to be realized in particular terms, by arranging the field in particular ways, in relation to the context.
3. Both phases of the process by which form is given to the field change the norms to which they consciously and unconsciously appeal. The appreciative phase changes them by the mere fact of using them to analyze and evaluate a concrete situation, for this may affect both their cognitive and their evaluative settings. The creative phase affects them by presenting new hypothetical forms for appreciation. The realization of the chosen form still further affects the norms involved, for it affects the situation, including its division between field and context. It would thus alter the stream of match and mismatch signals generated by the situation, even if it had not already altered the setting of the norms themselves.
This process of change is the focus of my attention, for I believe it is the key to our understanding of our predicament and of the scope of our initiative. I have argued that we know anything at all only by virtue of a system of largely tacit norms, developed by individual and social experience, which itself is structured by our individual concerns, and that this system has the threefold task of guiding action, mediating communication, and making personal experience meaningful and tolerable. It can change only at a limited rate, if it is not to fail in one or more of its functions. Its failures at the level of the individual can be studied in any mental hospital, and at the social level, in all the more disturbed periods of history, notably the present. Hence the importance of understanding the process of change, its possible patterns, and its inherent possibilities and limitations.
The system of tacit norms, which I call an appreciative system, tends to be self-perpetuating. Our mutual understanding and cooperation, our powers of prediction and effective action depend on its being widely shared and accepted. So any challenge to it awakens protective responses. Each generation has a powerful interest in transmitting it to the next. Representing as it does the accumulation of experience, it is supported both by authority and history.
In the social field it is also to some extent self-validating, since sanctioned mutual expectations tend to elicit the behavior which will confirm them. In the field of the natural sciences, where the variables are more independent, this conservatism is less likely to be self-validating though it may long inhibit change. Michael Polanyi25 lived long enough to see the adoption in his lifetime of a scientific hypothesis formulated by him forty years before, but barred from acceptance in the meantime by its departure from the then most acceptable style of explanation. In his account of this experience he expresses his approval of this degree of inertia, even though it nearly cost him his scientific career.
On the other hand, such systems also contain within themselves the seeds of their own reversals. Each is a work of art, however unconscious, and, like all works of art, attains form only by a process of selection which excludes possible alternative forms. These in time clamour for realization. They are kept alive in the meantime in those individuals and subcultures which are least satisfied by the accepted systems; and they grow at the expense of the accepted system as soon as that system ceases to command the confidence and authority of its heyday.
Furthermore and more conspicuously, the accepted system is challenged by changes in the context, often brought about indirectly by its own development which renders that context no longer appropriate. These changes may be in the physical or the
institutional or the social or even the intellectual context. All are abundantly illustrated in the recent history of the Western world. Physical exploitation has posed problems of pollution which turn growth from a promise into a threat. Market institutions, developing, have changed the nature of the market. Democratic political institutions, developing, have transformed the concept of democracy. “Liberal” values have made a world which increasingly rejects liberal values. Styles of scientific thinking, pushed to their extremes, reveal their limitations and subsume or are overwhelmed by their rivals. “ Teleology,” for example, a word wholly unacceptable to science even fifty years ago, attained respectability almost overnight as soon as it could be applied to manmade machines.
Finally, the accepted system may be challenged by collision with rival appreciative systems. This also is being illustrated by contemporary history as never before. In a world where interactions multiply on a planetary scale, inconsistent subcultures multiply by fission to attest the passionate need of each individual for an apt and shared appreciative system, however small the sharing group. It is in no way surprising that increased physical contacts across the world should have called into being not “one world” but more mutually antagonistic worlds than ever before.
It may be objected that this, even though true in those fields of scientia which are affected by human culture, is not true of the natural sciences. The world’s atomic scientists talk a common language, even though the world’s politicians do not. I have argued that this is true only as a matter of degree.
It seems to me possible, in the light of these ideas, to arrange the different fields of potential knowledge in an order which explains both the extent to which they are open to human knowing and the extent to which our acceptance of our knowledge rests on its survival of rational tests on the one hand and its congruence with tacit standards of form on the other. This “order” does not involve sharp breaks between “scientific knowledge” and “unsupported beliefs.”
It is generally recognized today that even in the natural sciences the scientific method does not “validate” its hypotheses. It can only test them and attach increased credence as they survive those tests. It is recognized also that credence develops at least as much from the congruence of the theory with the existing body of knowledge and from its facility in explaining facts other than those which it was devised to explain and in generating further hypotheses which depend on it.
Less commonly recognized is the limited extent of the knowledge confirmed even to this extent and the status of the remainder. Even in the natural sciences theories rightly retain their power even though well established facts show that they must be at least incomplete. For example, the ascertained facts of what is now (perhaps mistakenly) called extrasensory perception show that our current ideas of sensory perception must be at least incomplete. But in the absence of a theory to link what we do not understand with what we do understand, these facts await incorporation in the general body of knowledge, just as the evidence for biological evolution had to await its explanatory theory. Even an adequate theory may have to wait long for acceptance, as Polanyi’s experience showed, for no better reason than its departure from current fashions of explanation.
Equally often rival theories compete to explain the same set of facts, as did Ptolemaic and Copernican astronomy. The judgment that accepted the second was not the result of “rational” testing. It was not even a preference for simplicity. For Copernicus, retaining circular planetary motion, had as much mathematical difficulty in accounting for his observations as did his Ptolemaic predecessors. Yet his theory, rightly in my view, bears his name, rather than that of Kepler who first gave the theory its manifest superiority in simplicity.
The situation is even more extreme in the field which Herbert Simon has called the “Artificial.” For example, it is sometimes objected that most psychoanalytic theory is “unscientific” because it cannot be disproved. This may be so, but we are not therefore irrational in accepting it in so far as we judge it to serve our need better than others or better than none. Human motivation is complex and culture-bound. Why should we expect to “understand” it completely or once and for all?
The example is also a disturbing reminder of the relation between knowledge and design in the field of the “artificial.” However unsupported these theories may be deemed to be, countless families in the past seventy years have made them true for them simply by accepting them. And more generally they have become part of Western culture to the extent that they have affected our basic assumptions about the areas in which they operate.
It is a minor example of this, for Western culture has been profoundly affected by the findings, the methodology, the attitudes, and the outlook of scientists. It is not wholly the fault of scientists that what has passed into the general culture is grossly distorted in two critical ways. One is the mistaken identification of science with rationality. The other is the exaggerated dichotomy between science and nonscience. These two errors are nonetheless a grevious threat to our understanding of our own mental processes,
for they ignore two basic facts of human epistemology.
The first of these is that our basic knowledge of the world, our neighbors, and ourselves is a set of expectations based on exposure to the regularities of experience. Science has vastly amplified and refined these expectations, but what lies outside its reach is by far the greater part.
Second, the appreciation of form based on tacit standards is as basic to science as to the much wider area of our tacit and explicit assumptions. It emerges most clearly from a study of the great innovations in science, but it is equally important and far more common in conserving and securing general acceptance for the common assumptions on which all our cooperative activity proceeds, not least the cooperative activity of science.
1. Herbert Simon, The Sciences of the Artificial (Cambridge: The MIT Press, 1969).
2. A. O. Lovejoy, The Great Chain of Being (Cambridge: Harvard University Press, 1966).
3. In fact I understand that the theory of
particulate inheritance has itself been so qualified by deeper understanding
of the interactions of the gene pool that genetic theory today is more similar
in its actual effect to that presumed in
4. Christopher Alexander, Notes on the Synthesis of Form (Cambridge: Harvard University Press, 1967).
5. Alexander, Synthesis of Form, p. 198. note 21.
6. Hanna F. Pitkin, Wittgenstein and Justice (Berkeley: University of California Press, 1972).
7. The evidence on the subject of perception is conveniently summarized in M. L. Johnson Abercrombie, The Anatomy of Judgment (London: Hutchinson, 1960). The relation of cognitive capacity to neural development is of course the focus of most of the work of Piaget.
8. This was the focus of contention especially in the second decade of this century between gestalt psychologists (for example, Koehler, Wertheimer) and holistic philosophers (for example, Bergson, Smuts) on the one hand and traditional, analytic, reductionist science on the other. As so often occurs, the manifest facts on which the innovators were insisting were ignored because they were offered, or at least construed, as an “either-or” choice in which acceptance meant the rejection of equally valued insights on the other side. The debate continues to be bedevilled by the “either-or” disease even today when physics has blessed the concept of complementarity. Let us hope that neurophysiologists will prevail on the field on which psychologists and philosophers battled almost in vain.
9. David Galin, “Implications for Psychiatry of Left and Right Cerebral Specialisation,” Archives of General Psychiatry , October 1974, vol. 31.
This paper also contains an extensive review of the literature on this subject. For a special study of its implications for pattern recognition, see Roland Puccetti, “Pattern Recognition in Computers and the Human Brain,” Brit. J. Phil. Sci. 25 (1974):137-154.
10. Woodger, Biological Principles (London and New York: Harcourt, Brace, 1929).
11. G. H. Lewes, Problems of Life and Mind. Quoted in M. L. Johnson Abercrombie’s Anatomy of Judgment.
12. J. S. Bruner, J. J. Goodnow, and G. A. Austin, A Study of Thinking (New York: Wiley, 1956).
13. Milton Rokeach, The Open and Closed Mind (New York: Basic Books, 1960).
14. Professor Rhinelander, in his book/s Man Incomprehensible to Man, expresses his opinion that this view is “essentially accurate” even though it “is at odds with much current philosophical theory and… bristles with controversial assertions and implications.” (Portable Stanford, 1973, pp. 77, 78.)
15. I have developed this concept of interacting reality and value systems elsewhere, notably in The Art of Judgment (London: Chapman & Hall, and New York: Basic Books, 1965) ch. 4 and Value Systems and Social Process (London: Tavistock Publications and New York: Basic Books, 1968), ch. 9.
16. Notably in a paper “Digits and Analogues,”
published in the proceedings of the 1968 AGARD Bionics Symposium,
17. T. S. Kuhn, The Structure of Scientific Revolutions (Chicago: University of Chicago Press, 1970).
18. See M. Wertheimer, Productive Thinking (New York: Harpers, 1959) p. 214.
19. Arthur I. Miller, “Albert Einstein and Max Weitheimer: A Gestalt Psychologist View of the Genesis of Special Relativity Theory,” Hist. Sci. XIII (1975): 75-103.
20. Alexander, Synthesis of Form, ch. 5.
21. Well illustrated in the Buchanan Report on Traffic in Towns (London: H.M.S.O., 1963, p. 16)
22. Jeanne Bamberger distinguishes the formal structure of music from the (much less describable) figural structure imposed by the performer and the hearer and has shown that young children impose a figural pattern even on a sound sequence from which the performer has eliminated all but formal elements. (“The Development of Musical Intelligence I,” July 1975, unpublished.) She is Associate Professor of Education, Division for Study and Research in Education, Massachusetts Institute of Technology and Associate Professor of Humanities (Music) at the same institution.
23. When I refer to “distinguishing signal from noise” I do not wish to imply that there is necessarily only one distinction to be made. Many alternative divisions of figure and ground may be possible. Dr. Hans Selye has described how, as a young medical student making his first contact
with hospital wards, he was struck not by the variety of the patients’ symptoms but by the similarity which distinguished them all from the nurses and doctors around them. They all looked ill. He learned his appointed lesson, which was to distinguish and diagnose their disease. But he did not forget his initial insight. It was later to inspire what was to be his predominant life work as a researcher - the study of the body’s response to stress of any kind - which he was to call the general adaptation syndrome. Hans Selye, The Stress of Life (New York: McGraw-Hill, 1956) pp. 14-17.
24. I take this use of the word “context” from Alexander (4).
25. Michael Polanyi, “The Potential Theory of Adsorption,” Science 141, no. 3585, pp. 1010-1013.