Of Molecules and Men
The Biology of Ultimate Concern
Biology may be destined to be the science of the future, but there is certainly much about it that is very puzzling at present. Indeed, it is arguable that it can ever be a science of quite the same sort as physics and chemistry, because it has to deal with problems and concepts that these sciences can evade, at least in the more superficial parts of their structure. Biologists in particular are obviously expected to have a view about the status of man himself and the nature of the means that he uses to obtain information about the world and to describe it. Indeed, if the human biologist were really able to tell us what we want to know about ourselves, his account would be at the center of all science and indeed of all knowledge. The information about the knower should in principle comprise all that is known.
Thus paradoxically biology is both the last and the first of the sciences. The reason for this situation can be partly seen if we examine the slow and irregular line of progress by which man has been gradually finding adequate means to explore and control the world around him. Until very recently most thinkers, even the greatest ones, have felt it necessary to use a dualist principle in framing their basic systems, whether of philosophy or of science. Most have assumed that an account of knowledge must start with the “experience” of the individual. There have of course been plenty of materialists, many attempting to be thoroughgoing. But the basic systems of physics, as of philosophy, have been developed without questioning explicitly the status of man as an observer.
We can see how far the issue is from resolution by the fact that almost precisely opposite views can be expressed by biologists as distinguished as Francis Crick and Theodosius Dobzhansky. For example, Crick tells us that “I myself, like many scientists, believe that the soul is imaginary and that what we call our minds is simply a way of talking about our brains.” Dobzhansky does not tell us directly what he thinks about the soul, but he considers such matters serious enough to devote a quarter of his book to the views of theologians, especially P. Teilhard de Chardin. Crick is a molecular biologist and Dobzhansky a geneticist and evolutionist. Both deal with broad perspectives of biology. It is curious that although the evolutionist presents much the wider view, his thought often seems simple-minded compared to the brash biochemist. For example, Dobzhansky says, “‘cogito ergo sum’ is one certainty that even Descartes found it impossible to doubt.” The assumption of dualism seems to be necessary, even for the evolutionist.
THE ATTITUDE of the molecular biologist as a “pure scientist” is in general tough, radical, and skeptical. He uses words as he and his fellows please and leaves the worries about them to philosophers and other more timid souls. This is certainly the position of Crick. He writes directly, frankly, and indeed almost brutally. There is a ring of certainty in his sentences. After emphasizing that the question of how biological systems have arisen is the major problem of biology, he goes on:
The great news is that we know the answer to this question at least in outline…Natural selection, Darwin argued, provides an “automatic” mechanism by which a complex organism can survive and increase in both number and complexity. I say “automatic” to mean that we need not involve a special “life force” or “intelligence” to direct this process.
All this is very admirable and true but, in spite of the discoveries of molecular biology, it does not really carry us beyond the state of knowledge of a hundred years ago. One may agree that “the soul is imaginary,” but this does not tell us why so many people find it necessary to consider that they have one. Molecular biology has indeed given us a wonderful insight into some of the principles upon which living things operate. Most conspicuously it has shown how we can understand the nature of the stable systems of instructions in the nucleic acid molecules (DNA), which ensure the continuity of life. To have described this set of coded symbols in precise chemical terms is indeed a feat that most of us hardly dared to hope would be achieved in our lifetimes. Certainly it is only a prelude to great further discoveries, but it is important to realize that some of the critical ones have not yet been made. The working cell is an exceedingly complicated system. We are only just beginning to understand how the instructions of its DNA help to produce the controlled, steady state of its life. One may feel very hopeful that much of this will come to be understood—but we don’t know much about it yet. Still less, as Crick admits, do we know about the control systems of higher organisms, and in particular ourselves and our memory systems.
The importance of calling attention to these areas of ignorance is not to imply that we shall never know, but to urge people to find out. Crick quotes the examples of two distinguished American scientists, Elsasser and Mora, whose emphasis on what we do not know amounts to a form of vitalism. They seem to feel the need to attribute some special properties to life because, with current mathematical and physical methods, no completely tidy scheme can be produced. But can it in any science? Perhaps they are unrepresentative among biochemists and biophysicists and it may prove unnecessary to worry about such problems; but many people still do worry. The schismatic state of biology on such fundamental questions is shown by the fact that, far from dismissing such concepts as soul and mind, Julian Huxley and many others would regard the “emergence of mind” as one of the greatest steps in evolution.
Again, the mathematical geneticist Sewall Wright, “one of the founders of the modern version of the biological theory of evolution, nevertheless thinks that ‘Emergence of mind from no mind at all is sheer magic.”’ Surely Dobzhansky is right to conclude that with such marked differences of points of view close discussion of the issues is called for.
OBVIOUSLY IT IS EASY to exaggerate differences of points of view, as it is also to minimize them as owing to mere differences in language. Nevertheless it is a serious matter for biology that some of its practitioners should insist on ignoring an element in the material that others regard as fundamental. It is as if some physicists believed that there was a force of gravity, others that it did not “exist.” The division has gone on for a long time. Many psychologists from Watson and Lashley onwards have limited themselves to studies of behavior. Meanwhile some of the most eminent physiologists and neurologists have insisted on the primacy of some sort of mentality—whether it be that of Sherrington, Penfield, or Eccles.
The reasons for particular modes of thinking and expression must surely lie in the ways of operation of man’s brain. Unfortunately all brains are very complicated systems, the human particularly so. It may be some time before we reach as good an understanding of them as we have of the molecules of DNA. It is difficult not to believe that as this knowledge develops it will greatly alter what we now know as philosophy. It is curious, as Dobzhansky points out, how much analytical philosophy has leaned upon mathematics and linguistics rather than upon biology. Yet human biologists and anthropologists can provide us with some insight into the history of our ways of operating. Bernard Campbell, a young British anthropologist, has made a particularly satisfactory survey, especially of our origins. His account is firmly based in the concept that the various characteristics of a species serve to maintain a steady state of life (homeostasis). It is easy to see that this is so for lower animals. The tiger lives because he has the means to hunt and kill his prey, the deer because he can chew, digest grass, run away, and so on. Modern man gets his living mainly by his system of cooperation, based on communication by language. We have to recognize that our most important adaptive features are those that make this system possible. As Campbell shows, these include, for instance the more gentle and mutual methods of love-making that have been evolved by man, making possible the development of family life. This life in pairs has gained in continuity by suppression of the disturbing period of oestrus or heat of monkeys and apes, which is replaced by the system of almost continuous female sexual receptiveness. Again, the long delay in the onset of maturity by children has allowed for the process of education upon which the whole human system depends.
THESE ARE MATTERS which we have begun to understand moderately well in recent years, especially with the increased knowledge of the glandular internal secretions that play such a large part in the control of development and reproduction. Even more fundamental, however, are the adaptions by which we think and speak. Here knowledge is much less advanced, but very interesting developments are appearing. Campbell tells us much about the evolution of culture and tool-making, and just a little about the brain and its use for the production of speech. Penfield’s observations of the brains of conscious people by means of electrical stimulation have confirmed that the areas responsible for speech lie only in the left cerebral hemisphere (of right-handed people). Relevant to the problems of mentality and consciousness are the cases studied by Sperry and his colleagues after severance of the tracts that join one hemisphere to the other. Only activities of the right side of the body are then reported to be “concsious.” As Campbell puts it, this shows:
that speech is necessary to express consciousness. Unfortunately, the experiments do not show whether consciousness is also a correlate of the non-dominant hemisphere and therefore whether or not it is confined to animals with a means of symbolic representation.
THIS BRINGS US BACK to the question whether our worries about mind and matter are primarily a question of words and the means of representation. None of the books under review does more than mention the great advances that are being made by linguistic analysis. The particular point of relevance for the biologist is the growing suspicion that the capacity for grammatical speech depends upon the internal organization of the brain, matured under the influence of heredity in a suitable environment. This might indeed seem obvious as a general proposition, but the detailed analysis of linguists such as Chomsky and Lenneberg seems to be opening the possibility of a detailed understanding of the cerebral and other factors that are involved in language. Indeed, we still have surprisingly little information about how the semantic and logical systems develop in a child. The extensive studies of Piaget, for example, leave one intrigued, but appalled at how much there is to do. The linguistic analysts have covered many special aspects of the development of speech but they still do not tell us whether the practice of speaking about self, mind, awareness, and experience is a built-in feature of our communication system. It may be that study of the modes of operation of the brain and its early learning will provide clues as to why we have to think that such terms as “my feeling,” “my experience” indicate the existence of some inner mental entity. However much we learn later, we probably never lose the modes of receiving information and acting upon it that were appropriate to our earliest communications. When we were babies the human face was the all-important source of welfare, and all actions in the world around us came to be described according to it. Perhaps none of us can completely escape this fundamental source of animism, because it is the way in which our brains must work.
It seems likely that, as our methods of symbolization become better understood, they will also become so much more powerful that present mumblings will seem absurd. There is already a good deal of information on the subject that was not available to Paul Tillich, Teilhard de Chardin, or indeed to the well-meaning scientists who have been so sure that the appearance or extension of mentality is the special feature of man. It may turn out that what has appeared between animal and man is the adoption of particular techniques of symbolic communication. The resolution of this one question would free the energies of biologists for useful inquiry, relegating the vitalists, as Crick says, to the lunatic fringe.