Consilience: The Unity of Knowledge. Edward O. Wilson. 322 pp. Alfred A. Knopf, 1998. $26.
Like his hero Francis Bacon, Edward O. Wilson here takes all knowledge for his province and composes an eloquent summons to the reform of learning. He draws the arresting word "consilience" from Whewell's usage in Philosophy of the Inductive Sciences, where it has the sense of the accordance of two or more lines of induction drawn from different sets of phenomena. Knowledge, Wilson argues, is one at bottom. Science consists of strictly causal explanations of empirically established laws. Investigation encounters no fundamental boundary between the history of the physical universe and of humanity, nor between science and the humanities. The goal of consilience is to achieve progressive unification of all strands of knowledge in service to the indefinite betterment of the human condition.
This is a noble vision. Wilson sees its origin in the Ionian Greek belief that the cosmos is an orderly whole running by laws discoverable in thought. His own inspiration is the commitment of the 18th-century Enlightenment to enlisting secular knowledge in the advancement of human welfare and rights. What opened the prospect for modernity was the Scientific Revolution of the 16th and 17th centuries. The success of science in Europe then, and thereafter throughout the world, was owing to the fortunate concatenation of three features in the capacity of fine minds: insatiable curiosity, the power of abstraction, mathematical reasoning applied to natural phenomena. All phenomena, finally, are reducible to laws of physics that transcend cultural differences.
Put baldly, this sounds like arid monistic materialism. Wilson does not put it baldly. He brings to his subject a disarming mixture of personal modesty and intellectual rigor. His reading is wide and his learning extensive. He writes as well of arts and letters as he does of science. It is difficult to think of a finer evocation of Milton's genius than Wilson's passage on Satan's invasion of the garden of Eden. There is no question in his mind but that conveying the essence of truth and beauty pertains to the arts. The part of science is only to explain the possibility. C. P. Snow's division between the two cultures is better envisioned as a little-known terrain to be explored with good will from both sides. Wilson attributes the failure of the Enlightenment to carry the day to inattention to emotion and inability to establish secular grounds for ethics. He understands the turn toward Romanticism and admires the sensibility of a Goethe, who, bad though his science was, filled the void of feeling.
Equally tolerant of religious fundamentalists, among whom he was brought up, Wilson expresses personal empathy for their aversion to an evolutionary theory that has, however, become the only credible mode of understanding living nature. He even suggests that the blackest of his bêtes-noires, such theorists of postmodernism as Paul de Man and Jacques Derrida, whom he has read carefully, may have inadvertently performed science a service by forcing it to defend itself in a cultural debate. He admits, finally, that the argument for a scientifically based explanation of society and culture may be wrong—although if so, or if it is right and not put into effect, he sees no way out of the abyss into which unthinking plundering of our habitat is plunging us.
Wilson would now extend the reach of Darwinian evolutionary theory beyond the problem of explaining altruism, the centerpiece of his Sociobiology (1975). It here embraces all phenomena of culture and behavior. The bridge is a genetic account of the brain, the physical locus of the operations of mind and hence the seat of knowledge. For me at least, quite ignorant until now of the work he adduces in neurophysiology and cognitive psychology, this subject is the most fascinating in a generally engrossing book. Evolution of the brain occurred over the three million years between our simian ancestors and the advent of Homo sapiens about a million years ago. The strangest feature of the process is that the capacity of the brain should far exceed the needs of mere survival. A further curiosity is that, once the brain was fully formed, the enormous differentiation of cultures occupied mere millennia, while only the twinkling of an evolutionary eye separates us from the earliest records of any civilization. The time is orders of magnitude too brief for genetic evolution alone to have been the operative factor. The structure of the brain is determined by more than 3,000 of the 50,000 to 100,000 genes composing the human genome. The mind is the brain at work, and culture is the creation of manifold individual minds composing a civilization wherein the legacy is handed on from one generation to the next. Genes and cultures must be linked, as are the distant genetic history of the species and the recent cultural evolution of humanity. The great puzzle is how these complexes were, and are still, connected. As a start toward resolving it, Wilson adduces the notion of gene-cultural coevolution. Among paleolithic peoples, the genes imprinted upon individual minds certain pathways for mental development, certain epigenetic rules which, taken together, compose the complex that is human nature. Examples are the nearly universal human fear of snakes, the general taboo on incest and the transcultural uniformity of facial expressions. At this early stage in the evolution of humanity, these traits and others like them had obvious survival value while the individuals not so endowed were penalized and left an ever-diminishing posterity. The genes prescribing such rules thus spread throughout the species. Different peoples incorporated them into myth or religious prescription in accordance with local circumstance and behaved accordingly. Cultural norms, for their part, are passed on through generations, some proving more adaptive than others. Cultural evolution has been far speedier than was its background, or than is the accompanying genetic evolution. Nevertheless, the linkage is unbreakable. The right-hand side of the gene-culture hyphenation is never independent of the left, and the two are driven by the same law.
The difficulty with the social sciences, and notably with anthropology, sociology and economics, is that their adepts proceed as if tribal activity, social organization and economic exchange are entirely governed by their respective sets of rules. Wilson admires the great scholars who formed those disciplines. His account of their findings is sympathetic and interesting. Economics in particular has all the trappings of a scientific discipline, including regular recourse to mathematical modeling. But kinship patterns on the one hand and the functioning of the market on the other are solipsistic systems. Only when explanation of cultural and economic behaviors is carried back, largely by way of cognitive psychology, to their causal basis in biology will an analysis be scientific. The false boundary separating the social from the natural sciences will then be exorcised. All roads to the truth will be scientific. Evocation of the meaning and quality of life and experience will continue to be the province of the arts, their appreciation enhanced by an informed criticism newly aware of the cultural and genetic basis. The choice between a transcendental and an empirical foundation for ethics will vanish, leaving only the latter, while religion will be a vehicle for incorporating the highest values of humanity in the poetic form of myths consistent with reality.
This is a grand prophecy beautifully expressed. I can only hope that it comes to pass. Historian though I am, I share the author's predilection for both the Enlightenment and science and his distaste for postmodernism, a term that has all the appeal but none of the clarity of posthumous. Still, one has certain reservations. Wilson's most unsatisfactory discussion may be his attempt to rescue free will from the overall determinism of biological necessity. In his perception, our sense of making choices for which we are responsible is an adaptive illusion depending on our inevitable ignorance of the totality of material factors involved. More generally, an air of reverse Panglossianism hangs about the overarching competence of natural selection. To ordinary good sense, the proposition that all is for the best in the best of all possible worlds is no more persuasive when it is adduced as an outcome than it was when derived from Leibniz's principle of pre-established harmony. Its rejection by Wilson's favorite philosophes, Voltaire at their head, opened the program he would complete of enlisting science in improvement of the world. For them the nascent social sciences were to be the instruments, as in a scientifically based form they are to be for him.
Is that realistic? The stretch between the examples he cites of epigenetically determined behaviors and the complexities of contemporary society seems inordinate. Can we expect it to be narrowed anytime soon to the degree that will admit of developing socioeconomic programs cogently constructed on biological underpinnings? Can we really suppose that, having understood the full range of natural selection, humanity is about to outlive the process that has produced us and engineer its future by manipulation of the genome? Wilson himself cites the spectre of eugenics as a warning of what may go wrong. He also alludes in several passages to the problem of complexity as the greatest challenge facing all science. One has the impression that even in physics it is being met by the search for intermediate levels of explanation that may be put into effect in appropriate applications. How much more is that likely to be true, say, of economics. One would not wish, and Wilson does not wish, the Federal Reserve Board to be denied the guidance of monetary theory until its consilience with natural selection can be demonstrated.
To my way of thinking, the weakest feature of Wilson's splendid essay is (what was not true of Bacon) the lack of any political dimension. His theory of scientific knowledge is exclusively intellectual. With respect to cognitive aspects, that is, I agree, entirely correct. Wilson gets it exactly right when he dismisses the so-called sociological strong program that would politicize and socialize the content of science. Nevertheless, science is anything but apolitical in its application, practice and very possibility. What else but politics decided the fate of the Superconducting Supercollider, which might indeed have fortified the laws of physics? More to the immediate point, Wilson hails the guidelines adopted at the June 1992 Earth Summit held in Rio de Janeiro, and merely mentions in passing his regret that political quarrels have limited its implementation to lip service. His concluding pages are a powerful argument in favor of responsible environmental policies. We will have to hope that finding the will to enforce them is not contingent on widespread acceptance of the premise that knowledge is consilient.
The rain forest cannot wait.