A Biology of Russian Dolls

After a century of tissue rejection, the grafting of Darwinian evolution theory into the body of French thought is at last proceeding with all deliberate speed. One says “deliberate” because even now very few true evolutionary biologists are to be found in either the universities or the medical schools of France. The paleontological and physiological traditions of Cuvier and Bernard are still influential among French academic biologists and medical scientists; and neither of these essentially structural modes of thought displays any great compatibility with Charles Darwin’s populational approach. Yet at the pinnacle of the scientific hierarchy, at the Institut Pasteur and the Collège de France, there is a small group of remarkable biologists who are at last determined to achieve a successful transplant, and to install within the Cartesian world picture of French science a functioning account of variation, natural selection, and the rest—ideas that have hitherto provoked in France the reactions proper to “foreign bodies.”

The two principal figures in this group are Jacques Monod and François Jacob, who are internationally known for their “operon” theory. This theory is designed to explain how the biochemical processes taking place along macromolecules in cell nuclei are switched on and off, and so to account for the puzzling latency and intermittence of gene action. For why are not all genes active all the time? The philosophical attitudes underlying their enterprise were first presented to a wider public a few years ago in Monod’s book Le Hasard et la Nécessité¹ and now we also have Jacob’s La Logique du Vivant, in a perfectly respectable and readable translation.²

Jacob’s book was well worth waiting for. It is an altogether more serious piece of work than Monod’s, more tightly argued, better organized, and less rhetorical: an admirable addition to the popular literature of French science. Where Monod put forward a lawyer’s brief, in which the crucial distinction between the intentional (teleological) activities of human beings and the mechanically self-correcting (teleonomic) processes of biology was deliberately obscured behind the common word projet, Jacob tells his story absolutely straight. As a result, it is possible to see at last exactly what is going on: i.e., how this improbable union of neo-Cartesian physiology and neo-Darwinian natural history is being effected.

To put the point in the kind of biological terms that Jacob himself appreciates,³ the Institut Pasteur group sets out to achieve a viable transplant of Darwinian evolution by using the new science of molecular biology to inhibit rejection. Hitherto French biologists have found the theory of natural selection uncongenial because there was no clear way of meshing it in with the mechanistic view of bodily structures they inherited from Descartes. Until the creation of molecular biochemistry in the years after 1945, by Delbrück and Kendrew, Crick, Watson, and others,⁴ there was indeed no way of relating the population genetics on which neo-Darwinism rests—or even the chromosomal genetics of T.H. Morgan and his successors—to the actual physicochemical make-up of organisms and their minute parts. Molecular biology supplied that link. By means of the new concepts of macromolecular structure and the “genetic code,” it was shown that the unit factors of heredity first invoked hypothetically by Mendel, and later established by twentieth-century geneticists, have a quite definite and specific “structural” aspect. In a manner of speaking (it seemed) genes actually “were” molecules of nucleic acid.⁵

That is the key discovery toward which François Jacob’s entire exposition is directed. He is writing a history of ideas about heredity and organic reproduction, from the late sixteenth century to the present day—but it is history with a philosophical message and a ready-made destination. From 1600 on (he argues) the interlocking structures of le vivant have been unraveled step by step; the focus has narrowed from complete organisms to constituent organs, to cells and cell nuclei, chromosomes, genes, and finally macromolecules; and, by now, the hidden structures and mechanisms that impose a common logique on all the functions and operations of the living creature stand revealed. Inside every organism, smaller and smaller structures and systems are packed one within another like Russian dolls—the image is his own—and at the very heart, on the smallest scale of all, they can at last be described and explained in physicochemical terms.

Separated for so long from physics and chemistry by differences of method and concept, biology, Jacob argues, can at last join hands with the physical sciences. After a century of quarantine, Darwin can be made an honorary Frenchman:

Each living system has to be analyzed on two planes…which can be separated only for the sake of explanatory convenience. On the one hand, one has to distinguish the principles governing the integration of organisms, their construction, their functioning; and on the other, the principles that directed their transformations and their succession. The description of a living system requires reference to the logic of its organization, as well as to the logic of its evolution. Today biology is concerned with the algorithms of the living world. [Page 300, italics added]

Given his over-all synthesizing aim, and the compression that comes from dealing with 400 years in 280 pages, Jacob handles his historical tale with grace, style, and reasonable accuracy. There are some inevitable obscurities. For example: on page 47, he quotes Buffon calling in question the reality of all taxa, by saying, “There are really only individuals in Nature,” yet five pages further on—without warning—we find Buffon contradicting himself, “An individual is nothing in the universe…. Species are the only beings in Nature.”⁶ Still, when all allowances are made, Jacob’s historical survey is exposed to only one major objection; though this particular criticism (as we shall see) is highly damaging to his deeper philosophical message.

The point of contention has to do with the temporal or historical aspect of the theory of evolution. For Darwinists, the manner in which organic populations become adapted to their specific environments, and to one another, is quite as crucial a question as the physicochemical nature of the mechanisms involved in heredity. In Britain and America, accordingly, modern evolution theory has rested on two quite distinct pillars: one of them being cellular genetics, from which Jacob himself starts, the other being the application of statistical and genetical analysis to the dynamics of evolving populations. (This latter, populational analysis, was inaugurated by Sewall Wright, R.A. Fisher, and J.B.S. Haldane, and has since been refined by Ernst Mayr and G.G. Simpson, and more recently by Richard Lewontin, Richard Levins, and others.)

Despite all his concern with the “logic” of evolutionary change, François Jacob—believe it or not—tells us absolutely nothing about this second, crucial support of evolution theory. While he acknowledges that “adaptation” is a key feature of organic evolution, he mentions no attempts to analyze the concept of a “population” more recent than those of Malthus and Darwin. True: he allows that “the study of large populations and the introduction of the statistical method” has had important consequences for biology (page 195); but this leads him to discuss only Maxwell, Gibbs, and Boltzmann, the founders of statistical thermodynamics. So far as the most eminent French evolutionists are concerned (it seems) Fisher, Wright, and Haldane have written entirely in vain!

This omission is a bit of a giveaway. For the charm of Jacob’s basic analogy between structure and history—between the logique of physiological organization and the logique of temporal evolution—depends on keeping the historical messiness of populational changes under a hat. Statistical thermodynamics and information theory, its stepchild, are in fact theories of a very different kind from population dynamics and population genetics. The former are decent, ahistorical, Platonizing systems, concerned with physicochemical Being, and highly congenial to the Cartesian spirit. Population dynamics and genetics, by contrast, provide an essentially temporal, neo-Aristotelian account of organic Becoming, in which historical factors are the heart of the matter, not mere “boundary conditions” of some more basic, ahistorical theory.

If the adaptation of organic populations were simply one further statistical phenomenon governed at bottom by the laws of large numbers, like Boyle’s law of gas expansion, we might see it as yet one more consequence of timeless, mechanical processes. Unfortunately for Jacob’s case, this is not so. Darwinian evolution theory remains irreducibly historical, and continues even now to resist exhaustive translation into the ahistorical terminology of physics and biochemistry.

So there is something premature, even specious, about Jacob’s suggestion (pp. 299-300) that with the advent of molecular biology the older dialectical stresses in biological theory—discrete species vs. continuity of forms, mechanism vs. vitalism, etc.—have finally been outgrown; and about his idea that we can now construct a unitary pattern of theory—extending all the way from macromolecules to individual organisms, and on to organic species, societies, languages, and cultures—around a common general idea of organized systems, or “integrons.” (The neologism is his.)

Even within biology itself, to say nothing of human affairs, the dialectic between physical structure and historical adaptation is unresolved, and probably unresolvable. At the opposite extreme from such molecular biochemists as Jacob, for instance, there are those contemporary population biologists (e.g., Lewontin) who see subcellular mechanisms, of DNA replication, etc., as quite secondary to the understanding of evolution. Far from DNA macromolecules being identical with genes, they are merely the tactical means that populations employ in responding to the strategic, and historical, problems of adaptive change in varied environments. Nor will this opposition be easily overcome. In biology as in the human sciences, structural perspectives—in the spirit of Descartes and Newton—can at most complement, never displace, the temporal perspectives of Vico or Darwin.

The root of the trouble is this. Jacob declares, rightly enough, that

Biologists no longer study life today. They no longer attempt to define it. Instead, they investigate the structure of living systems, their functions, their history. [Page 299, italics added]

Yet there is no doubt that, for him, the greatest of these three is “structure.” Organic functions and history become truly intelligible to him only when accounted for in structural terms. Jacob’s entire history of heredity is, indeed, designed to establish a structural picture of organisms and their activities; and his parallel between the “logic of organization” and the “logic of evolution” leads the reader to understand that, once this is done, the temporal sequence of organic evolution, which is biological history, will prove to have a “logic,” conform to a “program,” and be governed by a “code” or “algorithm,” analogous to the logic / program / code of macro-molecular structure.⁷

This point is more than a parochial one. For the final twenty-five pages of Jacob’s book range, in conclusion, over the entire field of life and culture, behavior and society. In short order, Jacob sweeps sociology and linguistics, anthropology and political theory into the net of his Biological Structuralism:

A new hierarchy of integrons is thus set up. From family organization to modern state, from ethnic group to coalition of nations, a whole series of integrations is based on a variety of cultural, moral, social, political, economic, military and religious codes. The history of mankind is more or less the history of these integrons and the way they form and change. [Page 320]

There are essential analogies, in his view, between Nature and Nurture or between genetic inheritance and socio-cultural transmission; and these analogies are to be captured by adopting the language of information theory—i.e., by analysis in terms of “codes,” “messages,” and “programs.”

This vast extension of Jacob’s natural philosophy into human affairs may be appealing to students of transformational grammar.⁸ But the rest of us would do well to tread more carefully. For human affairs—notoriously, in Descartes’s own view—lack precisely the kind of tight and self-correcting, or “systemic,” organization typical of physiological systems in organisms. The “organization” of entire societies is something less than organic; the behavioral “codes” of human groups are only very partially codifiable; the so-called “social system” is a good deal less than systemic.⁹ In short, the integration of Jacob’s “cultural and social integrons” is far from complete. If the course of History did indeed conform to a standard mathematical procedure or “algorithm,” how happy that would have made Hegel! Failing that, the extension of terms like “logic,” “code,” and “algorithm” from molecular biology into evolutionary history—and still more into human affairs—involves a somewhat questionable set of metaphors.

Here again, of course, Jacob’s sketch of a sociology of integrons is in a familiar French tradition. (When did he last read Durkheim?) Yet the deficiencies inherent in any organic theory of politics, culture, and society are not overcome simply by restating it in the terminology of information theory and molecular biology. Far more to the point is Jacob’s suggestion that we explore further the parallels between sociocultural change and organic evolution.¹⁰ An evolutionary analysis of the processes by which cultures and institutions, languages and concepts change over time will, however, have to be an essentially historical and populational analysis. So the evolutionary analogies we need in order to improve our understanding of society and culture are those that come, not from molecular biology and cell physiology, but from population dynamics and population genetics: i.e., from precisely those aspects of organic evolution that Jacob himself ignores.

After all, syntactical and other “codes” can acquire a semantic sense only when put to use in larger human Lebensformen; “programming” is an activity by which computers are enculturated to our historical situations and problems; while—as our experience with nineteenth-century historicism testifies—“logic,” even when supplemented by “dialectic,” has proved a feeble instrument for the analysis of historical processes.

Like all Cartesians, the structuralists will no doubt go on trying to enclose the flux of history in fixed, universal categories; and the results of their efforts will often be illuminating, up to a point. But, in the last resort, the Protean character of history—especially, the history of human life and problems—will continue to overflow all such tidy boxes.