Of course, naturalism and dualism have changed over time, especially since the Enlightenment, whose philosophical, but not practical, children have plunged again and again into the Romantic sea. In principle, the opposite of "dualism" (or pluralism) is not naturalism but "monism." Metaphysical naturalists have often made concessions to spirit, and not just because it is always prudent--politically correct--to do so. Many leading dualists concede the truth (more recently, the "truth") of mature natural science, denying truth only to those parts, such as evolutionary biology,`that seem too clearly to exclude spirit, or that deal with qualities of matter that are "irreducible" because infused with spirit, or just too complex. But the naturalist stream, while by far the smaller, has floated many, perhaps most, of the new vessels of human thought these past 300 years. It has borne success, too much success, according to its enemies. As they see it, naturalism and materialism are responsible, via that feathers and wax contraption, technology, for the imminent collapse of Earth's life-support systems. How odd it is that modern dualists, for supporting evidence of this threat, depend solely upon seleced results of naturalist science; and how ironic that some of the most eloquent naturalists, including E. O. Wilson, are leading prophets of the collapse!

   But this gets ahead of my story. I want to discuss the boldest prognosis yet for the future of the Ionian Enchantment, made by the Icarian, Wilson, a quintessential naturalist. (Granted: the Platonic echo in "quintessential" is inappropriate.) I can barely touch here upon the likely response to it from adherents of the current version of dualism, whose condition has been described, even by some of them, as "biophobic"--the claim that biology (body) has little or nothing to do with human behavior (mind), especially with social behavior. I will epitomize it brusquely (actually, it can be quite subtly argued): biology explains nothing interesting about human behavior.

   The code phrase is "biological determinism." To be sure, such dualism has more to do nowadays with culture, or nurture, as antitheses of nature or body or matter, than with spirit or deity. Nevertheless, it is thoroughly dualistic and transcendentalist. The push for it now among Western intellectuals is more from politics (according to its defenders, from "the struggle for social justice") than from religion. It is dualism nevertheless in its denial that laws of nature coming from science offer any true or useful explanation of human behavior and society, or provide us any guidance.

Now I repeat myself--almost: E. O. Wilson's mature goal has been nothing less than unification of the intellectual achievements of our time. Given the growth ofknowledge since Whewell's day, this is an act of hubris even greater than Whewell's. Nor is Wilson's version of consilience exactiy Whewell's. He has borrowed but also modified the idea. Whewell may have hoped for refinement of theology to bring it into line with science, but he would surely not have applauded a public project of explaining religion through science. Whewell's consilience was of inductions within the best science, which was physical science. Wilson's version is much more than explanatory surprise within one or between two adjacent fields (although he gives us some stunning examples). It is more daring than that. Whewell, and other metascientists before modern Darwinism, might well have imagined in privacy a role for natural science in the understanding of human nature. But Wilson, armed by the scietific explosion of the last half-century, has already tried on wings and made some famous preliminary jumps. In Consilience he flies. Whether the wings stay on remains to be seen. Whether they do depends, oddly, upon how many others, similarly talented, care enough to join in the effort of flight. Wilson's consilience, a proposed standard of inquiry leading to truth, refers not only to propositions illuminating the facts within fields of inquiry and levels of organization, but across all the disciplines of knowledge, bottom-up and top-down--all of them.

   Are there examples? Yes. Wilson's book is devoted to them. All it needed for such a book to be written was hubris, encyclopedic knowledge, a sweatshop work ethic, and literary gifts. It needed a Wilson to offer the obvious conclusion to the 20th century knowledge explosion, anticipating and ignoring the inevitable sneers of reductionism and crude scientism. It took, above all, mastery of modern-evolutionary-biology, available to a thinker who has himself helped to create the subject and followed out its implications (what Daniel Dennett called "Darwin's dangerous idea"), all the way from ions at bilayer membranes to neurons, to brains, to emotions, to societies, across the boundaries of discipline and organization. There are a few such thinkers at work nowadays, not just one, but E. O. Wilson, by age and achievements, is first among equals.

   I leave for the reader's pleasure his book's case studies: physics to cell biology and neuroscience, neuroscience to mind. Genes to natural selection and evolution. Evolution to human nature. Human nature to culture. Culture to ethics. Ethics to religion. Instead, for variety and brevity, here is a case of my own, of consilience observed.

Here, however, a little more about Wilson's consilience. He is advertising, after all, an unfamiliar notion. In a chapter of his book entitled "Ariadne's Thread he takes Daedalus's Cretan labyrinth for a "mythic image of the uncharted material world in which humanity was born and forever struggles to understand." Ariadne, the daughter of Minos, loved Theseus. The clever girl gave her hero-lover a ball of thread, by the aid of which he found his way in the maze, killed the anthropophagous Minotaur, and returned to safety. The thread is Wilson's metaphor of consilience. With it, although we can never chart fully the knowledge labyrinth of this world, we (Theseus) can at least move about in it with confidence.

   But a less literary analogy may be, for all that, more instructive. Philosopher Susan Haack, author of Evidence and Inquiry (1993), has an analogy for the relevance of experience (sense data plus introspective awareness of mental states) to the justification of belief. (Remember: to believe is to hold a proposition true). Her model is a crossword puzzle. I simplify it for the present purpose, acknowledging its origin in Haack's work, and that said work is detailed epistemology, while what I offer here is not. Still, it seems to preserve the good sense of the original, which Haack has herself applied, in the Romanell Phi Beta Kappa Lectures, to the unity of inquiry. The clues to the crossword are the available experiential evidence (including recorded results of other, trustworthy inquirers). The filled-in downs and acrosses are beliefs about the clues, or the reasons for such beliefs. The probability that any new entry fits correctly depends upon the quality of the clue, the quality of entries already completed, and how much of the whole puzzle is complete. The better the clues, the more efficient the choice of entries, the faster the cells fill up. The more filled in, the better later entry guesses will be.

   Then, if we take the whole puzzle to refer to a body of knowledge--the past, present, and future of "human nature"--it is clearly prudent to include as many clues from science (such as evolutionary biology) as possible, alongside clues from other kinds of experience of "human nature." Surely, the past and present of human nature are to some degree explained by science. And good fits becoming evident as we proceed, even in unlikely crossings (such as, perhaps, cephalization with cubism), are consiliences. They reassure us when we are on the right track. There is every reason to expect that such consiliences will illuminate human nature, however we defined it initially, including such features of it as the idea of justice, features that seem, with most cells in the puzzle still empty, remote from science.

   Now, my distinguished colleague, philosopher Richard Rorty, who must here stand for other thinkers of like stature, is one of those who might well dismiss, not necessarily science in the practices of medicine and public health, or engineering, but its utility in the greater struggle--for social justice. "I do not have much use for notions like `objective value' and `objective truth,'" he admits. "I think the so-called postmodernists are right in their criticisms of traditional philosophical talk about 'reason.' "And he writes in the same place ("Trotsky and the Wild Orchids") that "at 12 [years of age], I knew that the point of being human was to spend one's life fighting social injustice." Rorty likes being attacked from the left as well as the right, to position himself as the sort of thinker who can do without the (Platonic) absolutes of the Right and the political illusions of the extreme Left. But utopianism remains for him the proper activity of intellectuals who care about social justice, about the elimination of cruelty. And therein he sees no significant role for science. Of the sciences since the 18th century, he wrote in Contingency, Irony, and Solidarity, "they have nevertheless receded into the background of cultural life.... It is not something to be deplored, but rather something to be coped with. We can do so by switching attention to the areas which are at the forefront of culture, those which excite the imagination of the young, namely art and utopian politics." In "Trotsky. . ." he makes this point: "There is nothing sacred about universality which makes the shared automatically better than the unshared. There is no automatic privilege of what you can get everybody to agree on (the universal) over what you cannot (the idiosyncratic)."

   But in science, the universal is better than the idiosyncratic. Wilson's argument is that we must exploit the actual and potential consilience of natural science with the human sciences and the arts in order to get at the uniformities, the basics, of human nature; that knowledge of those basics is necessary for an adequate understanding of the human condition, which is a social condition. That without it social justice will remain--just--a utopianism. Rorty seems to me (with all due respect) to be wrong on a number of issues regarding science, but here, especially, on universals. For him universals and searching for them are Platonism, elitism, invidious comparisons. Universalism distains or suppresses "idiosyncrasy." The odor of authority clings to it. Implicit is the humiliation of others, the work of bullies. But I see no justification thereof in history or in the outcomes of science. Rorty himself admits that since the 18th century the sciences "have...made possible the realization of political goals that could never have been realized without them." How did they accomplish that? Why, by identifying true (or nearly true) universals, such as the common origins, physiologies, aspirations, and feelings of all humankind, and refuting the false ones, such as the divine right of kings, natural slavery, and the general inferiority of women. Yes, by some scientists, and at various times, science has offered false universals, but those have been overthrown only by better science. And without reaching for true, or better-approaching-true commonalities, we would have only the idiosyncrasies of tribes, including those of whatever tribe you or I happen to belong to.

    Now, finally, I can touch the second utility in the consilience of world knowledge, in filling gaps between standing disciplines, not just among the natural sciences. The first, remember, was immediate utility: consilient science broadens knowledge of human biology to the point that some troubles (for example, infection) can be fixed, and life made better, more secure. That, surely, is a kind of social justice, by any definition. But the definitions of social justice themselves are of interest. Whence come they? To what extent do they differ among human societies? To what extent do all of them, if there are uniformities (which seem to exist), differ from whatever social justice means to chimpanzees? Since thtre are social arrangements most of the way down the phylogenetic tree, what regularities have they? How are they related to the conditions of life-reproductive strategies, physiology, development, ecosystem organization? What delights us? What, if anything, delights them? How did the physics and chemistries of delight and avoidance become embedded in brains, in societies? Filling such gaps in the puzzle must have eventual utility in application, like, but much broader than, the utilities of consilient physiology, pharmacology, and biochemistry in healing. What we can learn about the biological correlates of poetry, music, mathematics, a sense of justice, the urge to give comfort, the impulses of religion, must help us to understand--that is, to appreciate--them better. And to appreciate the deep meanings of these things is surely to diminish cruelty, to foster a fundamental kind of justice based upon respect for life.

   Wilson devotes his last chapter to utility. He identifies what he sees as the gravest problems facing all life on this planet, and attempts to show how important it is for us to recognize "a seamless web of cause and effect" in the operation of the world. Among such problems are the prospect of diverting evolution itself through molecular genetics (and genetic engineering), and of damaging the biosphere irreversibly by failing to check the human population explosion and our power to alter the landscape (both consequences of science). This is not the place to judge these. Wilson updates the advocacies of his earlier books. It is, as said, an irony that a pre-eminent metaphysical naturalist should see doom in successes of metaphysical naturalism. But I don't deny the formal cogency of his arguments. While they have to be taken one at a time and examined, his larger point is unexceptionable. These gravest of human issues are not social problems, are not scientific problems, not matters of]ocal politics, tastes, traditions, beliefs, idiosyncrasies. They are all of those, together, at one and the same time. That is the strongest argument for a scholarship of the gaps, that reports honestly and regularly to everyone, not just to allies and competitors in the business. The only question, for me, after long years among intellectuals, is this: are there ever going to be enough of them with the brains, skills in knowledge acquisition, honesty, self-confidence in humility, energy, and social support, to follow Ariadne's thread through the labyrinth, to complete enough of the crossword puzzle, to make a difference--really to put an end to human (and animal) sacrifice?

Reprinted from the Winter 1998 Wilson Quarterly

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