Mood music of the molecules
C. H. Waddington
The Nature of Living Things Stephen Black (Seeker and Warburg/William Heinemann Medical Books £1.95) Stephen Black has written a valuable little book which is well described by its subtitle 'An Essay in Theoretical Biology.' Its importance is more as a stimulus to thought than as an authoritative exposition couched in accurate and precise language. Dr Black sometimes uses technical terms in ways which may cause the professionals to raise their eyebrows: "The potentialities of this inheritance (from your forefathers) is called the 'genotype.' What you actually inherit is the 'phenotype'." Normal usage is to say that what you actually inherit are the potentialities of the genotype, while the phenotype is what these potentialities develop into in the particular circumstances of your life. But if the reader is prepared to see beyond such verbal quibbles, he will find that Dr Black is inviting him to consider some of the profoundest questions concerning the nature of living as opposed to non-living things. What he has to say goes interestingly beyond the conventional orthodoxies, and in some connections is highly original as well as penetrating.
In the first two-thirds of the book, Black develops the thesis that there is a "fundamental difference between the chemistry of life and the chemistry of the inorganic Universe. In the chemistry of inorganic matter the result of a reaction is exclusively the function of energy; and in the chemistry of biology it is also a question of physical fit, as in the construction of a jigsaw . . . life is what happens to matter when it mechanically responds to the information inherent in the improbability of shape or form."
This is a view which shifts the limelight away from DNA, which has usually been billed as the star performer in the cast of the biological drama during the last few years. Black's book is one of the first to describe, in a form easily accessible to the non-professional reader, the opinion that DNA has been allowed to monopolise the stage too long and is beginning to overact its part. Up until now this has been expressed mainly in rather specialist publications, such as the four symposia published by Edinburgh University Press as Towards a Theoretical Biology (see particularly essays by Howard Pattee), although it also formed some of the best parts in that peculiar curate's egg of a book, Chance and Necessity by Jacques Mono, which was aimed at and reached a wide public. Black's exposition, however,
is likely to be found both easier to understand than Monod's, and more revealing about the importance of the idea that the shapes of complex molecules,. of many different kinds, play a much greater role in living than in non-living systems. Unfortunately Black is rather too slapdash in defining the limits within which the idea should be applied. There are a number of systems which no one would dream of calling living, in which the shape of aggregates of atoms or molecules plays a crucial role. For instance, in the crystallisation of complex minerals, such as clays or micas, the precise pattern of arrangements of crystal imperfections or impurities controls the detailed form of the next layer of crystal to be laid down. The point that might have been made about such examples is that some authors (e.g. Cairns-Smith in his book The Life Puzzle) have been tempted to find in them the inorganic precursors out of which living things first evolved.
The most original — and, some readers are likely to think, the most outrageous — part of the book is its short final chapter. In this Dr Black attacks head-on the biological problem which has always proved most impregnable to man's understanding, namely the nature of mind. He does so on the basis of a lifetime's experience in a somewhat unusual field; he, is one of the small number of research scientists who have concerned themselves with psychosomatic medicine and hypnosis. He has long experience of the fact that non-material agencies, which most people would class as mental, such as the words spoken by a hypnotist to his patient, may bring about palpable physical changes in the patient's body; not only muscular movements, but also more deeplying biochemical alterations, such as failure to exhibit the normal allergic response to injected foreign proteins and the like. In such experiences the physical and the mental are commingled with each other more intimately than they are in those from which most people derive their ideas about mind and matter.
Black boldly takes it for granted that "ideas have always been in existence since the beginning of life — as ' meanings' established by association with molecular form in a vast complex of genetic and other information flows throughout the biosphere." He implies that this follows naturally from his earlier expositions of life as "a quality of matter which arises from mechanical realisation of the informational potential inherent in the improbability of form." He quotes in his support a remark about "the mind" of a polyp by a formidable authority, William James; but rather than pursuing a detailed analysis of the logical depths of this argument, he proceeds to develop a view of the mind-body problem capable of dealing with the facts of psychosomatic medicine and hypnosis. Very briefly, the basis of his thesis is that "there are two interrelated informational systems, cerebral and somatic . . . two kinds of mind in all higher animal species . . . there appears to be an underlying mood music of the molecules whiCh constantly influences our behaviour as well as our interpretation of the environmental, or sensory, input to the cerebral system." Here Black is raising problems to which no one can pretend to have a clear answer, and he is doing so from an extensive knowledge of very relevant evidence, about which most people are rather ignorant. His ideas have to be treated with respect, but they clearly call for a great deal more thinking through and chewing over. The reader is likely to be tempted to do a good deal of this himself, but it is much to be desired that Dr Black will give us another book, setting out in more detail his own thoughts on the connection between mind and the traffic of inform ation coded into molecular shape. • In sum then, a short book with much to offer, but, as in the case of many nourishing meals, its flavour will be better appreciated, and its nutritive value enhanced, if some of the dishes on the menu are taken with a pinch of salt.
Professor Waddington is Head of the Institute of Animal Genetics at the University of Edinburgh.