The Illusion of Sociobiology

The tradition of mixing the concepts of biology with philosophy and Weltanschauung stretches back into the last century and has Comte and Spencer as its unfortunate leaders: unfortunate, because their works are by now largely unreadable. Professor Wilson is sharply aware that his writing belongs to this tradition and he is aware of the dangers and deceptions within the tradition; particularly the danger that yesterday’s scientific speculations soon acquire a fusty look. Having been born in the excitement of today’s discoveries, they are then extrapolated into a golden scientific future, which turns out to be quite different.

Jacques Monod’s Chance and Necessity was an immediate predecessor of this book in usefully creating a stir and Professor Wilson also mentions the Huxleys and C.H. Waddington. They all called upon moral and political philosophers to take due account of the theory of evolution and of natural selection, and specifically to adapt their moral values to correspond to the scientifically ascertainable needs of the human race. They all accused philosophers, and humanists of all kinds, of being unnecessarily ignorant of the exactly known formative influences on human nature and of a willful innocence which left them pontificating in a void. Like the priests whom they supposed they had outgrown and displaced, philosophers were accused of turning their backs on ascertained facts in order to be consoled by their own moral inventions.

Professor Wilson says all these things in his new book, but with much more care and with more qualifications. He has not neglected philosophy in the academic sense, and he knows what limits philosophers are likely to place on inferences from scientific theories to moral requirements. He is much less dogmatic and confident of his conclusions than Monod was.

Briefly summarized, his argument runs like this: we have need now of a new discipline, called sociobiology, which will exhibit the junction of biology, in all its recently developing branches, with the social sciences. This new combined discipline will investigate the constraints that limit the options open to us when we wish to improve ways of life and social organization. There are fixities in human nature, as there are also points of plasticity and variability about which we may be uninformed. There are many sources within biology which can yield evidence about these constraints: studies of primate behavior, of brain physiology, studies of identical twins, learning theory, and, above all, studies within genetics of inherited traits and capacities, and of the physical basis of the transmission of them.

Professor Wilson alludes to some recent and current work in these fields, and much of his argument consists of predictions of future developments in these flourishing sciences. They should, he thinks, provide in future the explanatory background to accumulating knowledge in the social sciences; and by social science he seems to mean principally anthropology and sociology. He quotes liberally from social anthropologists to illustrate presumed constancies in sexual roles and in habits of religious observance. He infers that these have a hereditary basis and that they can be seen to confer a natural advantage on human populations organized in social groups. He means a natural advantage in the biologists’ sense of contributing to the adaptation of a population and hence to its survival, though not necessarily to the survival of the individuals who carry the advantage. Sexuality itself can be seen as a naturally selected device to ensure pair bonding, and it is simply bad biology to think of sexual intercourse as primarily designed for reproduction, as the natural law doctrine of the Catholic Church requires. Biology, in this view, corrects moral and social theory.

Professor Wilson characteristically avoids the better known errors of inferring from the behavior of primates to the behavior of men, and he avoids the use of concepts like aggression and territoriality in making such inferences. He remarks that “there is no evidence that a widespread unitary aggressive instinct exists.” He dismisses the claims, familiar in best-sellers on popular biology, that men are uniquely destructive within their own species, or that the persistence of warfare and factional infighting is to be interpreted as a variant of defense of territory, as known in some other species. He does not fall back into any of these variants of simplified social Darwinism.

The theory holding his argument together is that genes establish limits within which culture can develop both as unexamined social convention and as conscious belief. Sometimes a cultural trait is a hypertrophy, or enlargement, of a physically founded disposition and sometimes culture develops by playing variations on a basic, physically determined theme. For example, a tendency to polygyny—the mating of the male with more than one female—probably has an inherited physical basis and confers a natural advantage on the species; but the forms that it takes—polygamy, monogamy, mistresses, multiple marriages and divorces—may be very various.

Professor Wilson even surmises that there is an inherited need, represented in gene pools, for some kind of represented for the sacred, and that this need, passed from generation to generation by physical, not cultural, transmission, sets a limit upon the possibilities of a bare, scientific enlightenment as a basis for social cohesion. Just as the inherited need for pair bonding and some family ties probably makes ideal communal living impracticable, so, according to Wilson, there is an inherited need for some “sacralization,” with its accompanying myth, a need built into the human constitution. This is due to the long tested and selected advantage to a population of preserving social cohesion over many generations; and “sacralization” is a means to social cohesion.

The disputable hypothesis here concerns the method of transmission of these supposed human constancies rather than the constancies themselves. Professor Wilson is distinguishing between, on the one hand, human traits which have been naturally selected as conferring an advantage on descendants and which have therefore been physically transmitted through a population, and, on the other, human traits which are transmitted through specific social customs, and he argues that there is a physically inherited tendency of men to conform to social customs, whatever the customs may be.

The substance of his thesis is the guess that many more of the recognized human constancies than is generally thought are physically, rather than socially, determined. Standing behind this thesis is a philosophical claim that is not fully worked out but that is clearly implied and once or twice stated: that thought and belief and sentiment, and all that composes culture, are epiphenomena in human nature. That is, human nature is in the first place constituted by the transmission of genetic material which incorporates a program for human behavior—a program, however, that has a certain range of indeterminacy and that leaves options open.

The preprogramming, Wilson acknowledges, is unspecific when compared with the preprogramming of other species, and the cortex, and the human brain as a whole, is (as far as we know) a uniquely elaborate piece of machinery, designed through natural selection to record and respond to an immense variety of stimuli with an immense variety of patterns of behavior. More particularly, the human brain is now adapted not only to learning languages but also to pursuing knowledge indefinitely, and these inbuilt dispositions lead to complexities and elaborations in behavior which cannot be computed, even in outline. The question of whether there is a sense in which the multiply varied human responses must be assumed to be determined, even though they are probably incalculably complex, Wilson leaves to one side, wisely.

Professor Wilson naturally concludes that we can now apply the knowledge of biological possibilities and limits that we have just acquired in more intelligent social planning. His last chapter has the title “Hope,” and this application of biology to social science and planning is the hope. Men have, he says, inherited mythopoeic tendencies which served them well in primitive conditions, and he believes that scientific materialism by itself will not be rich enough as a replacement for religion and as solid social cement. What he calls “the evolutionary epic” is “probably the best myth we will ever have. It can be adjusted until it comes as close to truth as the human mind is constructed to judge the truth.” If the rather obscure end of this last sentence is overlooked, one can hear once again the steady hum of scientific optimism which was first given classical form in Condorcet’s great “Esquisse d’un tableau historique des progrès de l’esprit humain.”

This very bare summary of the argument is unfair if it has not given an impression of the good sense with which Wilson’s claims for scientific enlightenment are advanced, and of the caution with which the underlying issues of choice and determinism are reasonably left on one side. But still the argument of the book, and the philosophical assumptions behind it, seem to me misconceived and wrong.

One root of my disagreement is that Professor Wilson’s scientific materialism stops short of being materialistic enough. For instance, in the chapter on religion he asks: “Is the readiness to be indoctrinated a neurologically based learning rule that evolved through the selection of clans competing against each other?” The concept of indoctrination, I think, has no place in a physical science, and vast obscurities are concealed in that phrase “neurologically based.” One man’s indoctrination is another man’s learning, according to their evaluations of the propositions learned: do they have a different physical basis? Or again: “The mind is predisposed—one can speculate that learning rules are physiologically programmed—to participate in a few processes of sacralization….” But sacralization is not a concept that can be fitted into physical theory, if only because no criterion or sufficient test of whether a process is a process of sacralization is to be found in observable behavior. The thought of the subject is essential, as it is also essential to distinguishing indoctrination from other learning processes.

Another example of an inherited trait cited by Wilson will serve as a contrast: the dispositions that are involved in competitions among males for dominance in a group, and in recognizing and deferring to the dominant male. Being value-free and having behavioral criteria, these can be sufficiently revealed to observation, or can be tested by experiment; skilled observation may be sufficient to show, without indeterminacy, whether or not the dispositions are present. Therefore male dominance is a concept that can be introduced into a scientific theory without obscurity or indeterminacy.

Where the line is properly to be drawn between that which is observable and that which is not observable or testable is within limits open to discussion and argument; and more or less austere and restrictive definitions can be accepted for different purposes and in different sciences. Similarly, what counts as thought is also variable, although only within limits. The objection that I am bringing against Professor Wilson’s kind of scientific materialism, so called, is not just a methodological one, nor is it a technical point in the philosophy of science. Nor is it an objection which empiricist philosophers of the present day would particularly stress rather more than rationalists. It is a more general issue which has been at the center of philosophy since the seventeenth century, and the objections to sociobiology as a possible science cannot be understood until this issue has been clarified.

Like most men who in the last resort follow established common-sense habits of thought, and who temper common sense with love of the natural sciences, Professor Wilson is an “interactionist,” believing that there will turn out to be natural laws, scientifically established, exhibiting a two-way causation between mental and bodily states. But he is an interactionist who thinks he is a materialist, because he also believes that the dominance of physical causes in interactions between mind and body have not been understood up until now.

This is why he speaks of thought and of culture as epiphenomena in relation to the physical causes operative in heredity. This view of causal dependencies between body and mind is the natural response of common-sense thinking to the accelerating success of the physical sciences; and yet it is, I believe, and an incoherent view when its full implications are traced; it is a halfway house, a working compromise. The implicit incoherences of the compromise lead to no trouble, and are scarcely even noticed, until a theoretician, scientist, or philosopher comes forward with a speculative project such as sociobiology.

The incoherences come to the surface as soon as we enter the sphere of systematic theory. We can happily talk about psychogenic lesions and psychosomatic illnesses as a way of recording regular correlations between the physical and mental that we have noticed in ordinary experience—as long as we do not ask for systematic explanations of them. As unquestioning and practical interactionists, we have an embarrassing thought and we find that we immediately blush; the correlation between our thought and its physical effect seems clear; we take a tranquilizer and immediately have more serene thoughts. This level of knowledge of causal connections between mind and matter is exactly like the empirical knowledge of causes which enables most of us to manipulate physical things without knowing the laws of mechanics which would explain their reactions. But if we have serious plans for future research, we had better find an engineer who knows some mechanics and physical theory; and sociobiology is intended to be a science and not merely an unexplained list of useful causal correlations.

The incoherence of Professor Wilson’s project for sociobiology is probably best explained by the example of Descartes; he was certainly not an epiphenomenalist in Professor Wilson’s sense, but he did foresee the essential problem which a systematic physics would present to common-sense thinking. Every physical motion, whether on an astronomical scale or a subatomic scale, has to be explicable by universal laws of motion, quantitatively expressed, and these laws are themselves intelligibly related parts of a single systematic theory. This requirement applies to the motions of a man’s body, and of his limbs, no less than to any other observable object. So when I go for a walk and wave to a friend, these observable movements must have a complete explanation, with any degree of precision required, within the laws of physics and by reference to initial conditions stated in physical terms.

When adequate explanation, in the sense of lawlike and systematic explanation, is in question, physical changes can only be explained by physical changes, and no spiritual forces can burst in from outside, as it were, as if by miracle. So much for what Descartes required of the physical sciences. Equally, and on the other side, thought has its own connectedness and continuity, a connectedness that is quite different from that of things extended in space; and a thought can only be adequately explained through its connection with another thought in accordance with universal laws of thought. There are evidently looser causal connections, well known at the empirical level, between states of body and states of mind which include thoughts; and we rely on this empirical knowledge from day to day. But it is not knowledge which has the structure and organization of a science.

Descartes was a dualist in the sense that he represented the created world as divided into two self-contained domains of objects in space and of thoughts, and the two domains have a meeting point in human personality. Professor Wilson, in his plans for sociobiology, represents thought, as it enters into culture and social customs, as in part to be explained scientifically by physical determinants, without claiming that there can be an adequate explanation of physical states outside physics. Biology therefore advances into the territory of the social sciences, but no reverse process of social scientists explaining physical phenomena to biologists is called for.

Professor Wilson has the Cartesian spirit in that he predicts more secure foundations for knowledge in the human sciences on the basis of the sensational discoveries in molecular biology in the last thirty years, as did Descartes on the basis of Galileo’s physics. But he seems not to have heeded the case repeatedly made against Descartes. When I go for a walk and wave to a friend, the scientific descriptions of motion and change in the language of physics and biology make no reference to the gesture of waving, or to friends, or even to going for a walk. These are concepts from the mixed descriptions of common sense, and common sense is not principally concerned with the purely physical mechanisms that will explain the observed physical events scientifically. This mixed vocabulary was not designed for the purposes of scientific theory or for adequate explanation. Rather it has developed to meet the needs of communication between persons, and, most important, to meet the needs of decision-making and of discussing intentions and sentiments with others.

The beliefs, desires, sentiments, and intentions that initiate and guide my actions have been formed in my head, or heart, for some good or bad reasons, and often for reasons which I then explain to others. At the same time I see the behavior of others as indications of their beliefs, desires, and sentiments and as realizing their intentions. Our verbs of action and names and descriptions of persons and things—e.g., “waving,” “friendly,”—depend for this meaning largely on the social institutions, customs, and rituals to which they refer, or which provide a necessary context for them.

A keen-eyed observer from outer space, where they have quite different ways of life, would not see the point of much of our behavior, and would not be able to infer the beliefs, desires, and sentiments which inspire it. He would not recognize the furniture, or classify patterns of behavior as we do. The options open to him in his planning would be correspondingly different. Similarly, an old man arriving in contemporary California from some backward area might not be able to identify what middle-aged professors are doing running through the streets in shorts: they are running, plainly, but with what intention or meaning? “Jogging” is the name of a new institution, with a particular context of belief and desire, and to identify someone’s running as jogging implicitly invokes this background and setting.

It is a general characteristic of common-sense and prescientific descriptions of conduct that the imputation of intentions and sentiments to the subject always invokes a context wider than any one particular occasion. What a man can be truly described as intentionally doing depends on the range of his beliefs and interests, and these in turn depend in part upon his culture, in the sense of the social customs and the language which he has learned; and what the action is depends also on the social circumstances surrounding it. Tarzan might go through the same motions on a sunny afternoon in the jungle as the California professor; but certainly he is not jogging.

These features of common-sense discourse about persons are not accidental or alterable. They arise from the fact that we must use the same vocabulary in thinking about our own present decisions as in thinking about our past behavior and about the behavior of others; while we have to invent a special vocabulary, with its own distinct type of concepts, for purely theoretical and scientific purposes. To take one example of the necessarily mixed categories of common sense: when I ask myself why I am doing something, I ask myself for the reasons that explain my action; when from curiosity I ask myself for an explanation of this same conduct in retrospect, this reason becomes also a cause, or causal factor. But it is not the kind of cause that has its place in explaining the operations of a physical mechanism, whether at the biological or chemical or fundamental physical level. Its operation is not experimentally established, and it does not have the degree of independence of its effect, and also of its unobserved setting, which experimental confirmation requires.

If I want an explanation that will be not only exact and testable but also that will fit into a general and systematic theory, then I must change the terms under which my conduct is considered. In satisfying these demands for comprehensive and exact explanation, I shall find that I am investigating the mechanisms of the performance rather than the performance identified and described as a social and cultural phenomenon, and as an expression of thought. The descriptions of behavior which can be fitted into a scheme of scientific explanation must be appropriately determinate and exact; they must not depend for their interpretation on the context of use and they must be equally testable by all observers. Psychological terms, drawn from the common vocabulary, do not satisfy these two central conditions.

The central incoherence in the idea of sociobiology arises at the junction of two forms of explanation which, serving different purposes, cannot be welded into a continuous whole: physical theory lies on one side of the join, and what Professor Wilson calls culture, the domain of the social sciences, and particularly of anthropology, lies on the other side. It is important that one should not see this irreparable break as a division in reality, but rather as a division between two divergent sets of human interests, both irreplaceable interests. The division between the extended, or spatial, world and the world of thought has generally been represented by philosophers as a metaphysical division and as such left altogether unexplained. Professor Wilson similarly conveys a picture of the superstructure of culture imposed on the main structure of man’s physical nature, with the consequent idea of a single science which would represent the workings of both.

But this picture can be, and should be, reversed, by taking as the starting point not the ultimate nature of reality, but the needs of human beings, one species among other products of evolution, who happen to have developed a physical mechanism, the human brain and central nervous system. This mechanism confers some peculiar powers: principally the power to develop forms of speech, and therefore forms of reflection and of self-consciousness, which permit forward planning of future action and also the search for laws of nature, and these in turn open up new technologies at an accelerating pace.

These technologies will increasingly be used not only to develop greater powers of perception, but to improve the performance of the brain and of adjuncts of the brain. The structure and development of scientific knowledge can be studied as a form of human behavior, but this second-order study subdivides into two quite different enterprises. The first is the study of the physical mechanisms of human intelligence, principally (at the present state of knowledge) the physiology of the brain and machine simulation of mechanisms of thought. The second includes a historical study of the habits of thought and of the social settings which are likely to be favorable to the development of knowledge. It includes as well a study of the strategies which, at different stages of knowledge, are likely to be most successful. And these second kinds of studies require philosophical, as well as historical, reflection.

I am not arguing that there are only two types and forms of inquiry: inquiry into thought and culture, and inquiry into physical mechanisms. My argument does not support a dualism in this sense. Rather my claim is that human beings, while studying themselves and their own kind, must pursue at least two irreplaceable types of inquiry because of their own nature as embodied and self-conscious thinkers. One is an inquiry aiming at a purely theoretical understanding of their own physical functioning, in which human beings are seen as objects that conform to universal laws of nature; the other is an inquiry aiming at an understanding of their own thinking, and the thinking of others, in various normal social settings and in different languages.

The alternation between two viewpoints, one from that of disinterested observer and the other from that of social agent, constitutes the peculiarity of our species. Professor Wilson’s materialism stops short of recognizing that physical theory, as it has developed, is not concerned with matter, as this word was originally understood; rather physical theory retains its identity as an inquiry in virtue of its purpose and of its structure, as being always experimental and comprehensive and exact. The force of gravity was sometimes thought in the eighteenth century to be too immaterial to be acceptable in physics, and the forces and particles that constitute the elements of the physical world, as revealed in modern physics, are more and more remote from the medium-sized material things such as a man’s palpable body. No one can predict what will be the elements picked out as fundamental in physical theory fifty years from now, if the human race suffers no catastrophe. But we can be fairly sure that the mechanisms of genetic endowment, and of the operations of the brain, will be increasingly understood as deterministic, or semi-deterministic, systems, some of which can be to some unknown degree controlled by physical inputs through new technologies.

This understanding of bodily processes does not entail a loss of the autonomy of thought which follows its own laws in deciding which manipulations of physical reality, including the human body, should be undertaken and with what purposes in view. The notion that men think with their brains before making decisions, and that their brains function in conformity with physical laws, should be no more disturbing than the recognition that men see with their eyes, which equally conform to the laws of physics. The thought that enters into their decisions and actions, like the thought that enters into their recognition of objects seen, is governed to some degree by logic and to some degree by the syntax and vocabulary of a particular language, and to some degree also by the association of ideas in an individual’s imagination. Very different thoughts, conforming to the laws of thought, will accompany the same physical transaction in different men or in the same man at different times.

In his trenchant polemic against sociobiology and Professor Wilson,^* Professor Marshall Sahlins remarks, for example, that the same genealogical and physical family relationships bear utterly different labels in the context of different social customs in different societies. As an anthropologist he denies that there can be a valid argument from general genealogical facts to the natural selection advantage conferred by particular sexual customs and particular family relationships. For these customs and relations are not characteristic of the entire species and they serve the function of providing social cohesion under different social conditions, and not the function of ensuring the better survival of a gene pool under comparable physical conditions.

Professor Wilson in effect ignores the distinguishing feature of human beings: false speciation, as it is sometimes called—namely, the attachment of normal men through thought and language to the habits, and way of life, of a particular subgroup, accompanied by some measure of hostility or indifference to the habits and ways of life of other subgroups of the same species. That human beings are innately disposed to learn some language, but are not innately disposed to learn one particular language, is a fact about human beings which provokes a question in natural history: what advantage was conferred on the species by the disposition to learn diverse languages and to fall into tightly coherent social groups which are often hostile to one another?

This question may be unanswerable, or unanswerable within the limits of present knowledge. But it is at least evident that this linguistic dispersion of the species is only one part of a deep-seated characteristic of dispersion, and that therefore the truly scientific study of human nature, necessarily concerned with universal laws, will leave the explanation of human thought, conscious and unconscious, untouched, except for the abstractions of logic, which are detached from the grammar of any particular language and also from any particular social context.

It is not difficult to understand, from direct experience, that our thought interprets bodily movements and physical change, whether they are our own movements or not, in accordance with regular sequences or chains of thought. These sequences have to be understood in their own terms as thoughts, governed by the continuities of thought and not by laws of motion. I have to know something about the concepts that are liable to be present to a man’s mind and the alternative actions that he is likely to consider, if I am to explain his thought and intentions. To explain his thought at any particular time, as also to explain my own, entails filling in the context of surrounding thought. To explain the intentions and purposes that animate my behavior at any time entails specifying my desires and my beliefs about my situation; and it also entails filling in the context of thought surrounding these particular desires and beliefs.

Asking why I have particular thoughts immediately raises the need for a justification and endorsement of them; most of the thoughts that are dragged into my conscious scrutiny have probably been formed in preconscious thought, far away from critical scrutiny. Fitting my thoughts into a coherent pattern of thought is both correction and explanation, and is not the discovery or the invention of a mechanism.

Social anthropology, often cited by Professor Wilson, is a disciplined inquiry into human nature and culture which is a “social science” for the purposes of university administration. But neither in method nor in purpose does the inquiry have much in common with the physical sciences. It is not an experimental science, and it does not attain, or generally aim at, comprehensive, exact, and systematic theories. Rather it tries to interpret the distinguishing habits of thought and the intentions incorporated in the social customs of the indefinitely varied social groups which are open to study. Its method is interpretation and translation, and the provision of a context of thought for beliefs and desires which otherwise, and considered in isolation, are unintelligible. Anthropologists try to exhibit as coherent in all their variety customs and conventions and religious and sexual practices and family arrangements and arts and games. These are all expressions of thought, not objects of exact and systematic scientific theory.

In arguing against Professor Wilson’s sociobiology and scientific materialism, I have continually mentioned thought, and the explanation of thought, while Professor Sahlins, like many other anthropologists, writes about “symbolic” systems as his objects of study, using Ernst Cassirer’s terminology. To the degree this usage omits considerations of the full range of thought, with all its complexities of practical reasoning and reflection, it seems too restrictive.

Also, there is a philosophical point to be made by the use of the word “thought” when materialism is in question. The distinction between understanding and explaining thought by reference to causes, and understanding and explaining physical change by reference to causes, is a distinction made unavoidable by the most elementary facts about us: particularly, the fact that we are born with the physical equipment that makes it possible for us to think and to talk to others about our activities and movements tomorrow. The most tough-minded scientific materialist, who is ex hypothesis an active thinker, has to think of his future in the light of his accumulating knowledge of the natural course of events. He knows that accretions to his knowledge of independent causes will present him with new possibilities of action, to which he may wish to respond differently.

All this he knows most vividly and directly through the control of his own body, which places him in the observed physical world and ties him to it and makes him conform to its physical laws. He is not only, or principally, the observer of his body; he is also the thoughtful interpreter of its movements; his thought lends them sense and direction, in so far as he interprets them as conforming to his desires and beliefs. He will think of his body’s movements as his “actions” when they conform to his leading desire and when he knows or believes that the immediate cause of the movement is in him, and in the physical embodiment of his desire in the structures of his brain.

If he is a thoroughgoing scientific materialist, unlike Professor Wilson, he will not think of the relation between his desire and its physical embodiment in the brain as a causal relation; he will point to a parallel between this relation and the relation of the physical processes of color vision to the recognition of colors. Just as the same genealogical relations—e.g., that between maternal grandmother and son, or between aunt and nephew—may be interpreted by different concepts in different kinship systems and different languages, so there will be many different intentions embodied in movements which, from the standpoint of a scientific observer, are the same movement. One does not therefore need to go to the exalted level of the academic disciplines to find that the scientific materialist is one who believes that the world as we observe it proceeds in accordance with the laws of physics, and that our desires, beliefs, and other thoughts, including the belief in materialism, have a perceptible, and therefore physical, embodiment in the brain, as our perceptions have a physical embodiment in the eyes. But the scientific materialist should also recognize that the nature of these thoughts, including the belief in materialism itself, can only be adequately explained by their contexts and by the connections peculiar to thought.

The sense in which Professor Wilson is not sufficiently a materialist is that he expects too much from immaterial causes in science, and from a technology based on them; and this is the vice of all those who still expect too much from the social sciences, and particularly from sociology. It is by operation on the physical mechanisms of heredity and intelligence that we can expect planned changes, for better or worse, of a kind that could not be achieved by persuasion and argument—that is, by thought.

Sociobiology as a project has the ring of Condorcet’s optimism, of the hopes of the Enlightenment and of Comtean positivism; it suggests a picture of the history of different societies and cultures as best understood as a history of humanity’s successive adaptations to a natural environment. Apart from being philosophically incoherent, this seems to me a dangerous illusion about history. Catastrophe is also a feature both of natural history in biological time and of the comparatively short history of human cultures. Improbably favorable mutations that lead to better adaptations to particular environments in the short run can also lead to maladaptation and extinction in the longer run. Do we know that the developments of the brain associated with intelligent speech and self-consciousness and social diversity may not in the longer run prove disastrous? If forced to speculate in the longer run I think that it is a reasonable belief, on present evidence, that the species will not for very long survive and will prove to have been in this sense an evolutionary failure. Dispersion through language and custom may be a net disadvantage in the long run.

Obviously this is as much mere speculation as a contrary belief would be. But the better contribution of a biologist might be to indicate the chanciness of human survival and the very narrow limits of human knowledge. Seen from the standpoint of contemporary physics and contemporary biology alone, and without the consolations of revealed religion, human knowledge of the universe must always be a very small thing and the future development of science entirely unpredictable. Our categories and concepts are limited by our powers of observation and of thought, and we do not know how far we may extend these powers by manipulation of their physical embodiments. But we have no assurance of a unique destiny for the human race, unless from supernatural evidences.

Recognition of the contingency of evolution and of natural selection should reasonably be combined with recognition of present uncertainty. Neither with respect to survival nor with respect to the perspective from which we learn about the universe are we uniquely privileged, as far as we know; and the record does not suggest that we have a very distinguished and happy future. The monuments of human thought, and not least the physical sciences, are evidently impressive. But our knowledge and understanding will always be narrowly limited by our inherited physical constitutions, and there is no reason to believe that we have some central or essential part in nature’s whole design. The universe would proceed regularly on its way without human beings. If it does, perhaps the dolphins, and also the whales, will move untroubled through the silent seas, evolving still along their own appropriate path.