Harvey Mansfield:

It is a pleasure to comment again on Fukuyama's remarkable article of ten years ago. I continue to think "The End of History" to be an overinterpretation of the fall of communism, but I also still wonder at the ingenuity and breadth of the author. Fukuyama, with his knowledge of philosophy, easily surpasses the political science theorists who possess nothing but second-hand Kant, or misread snippets from Thucydides, and whose constructions remind one of an immense suburban development of small houses, all built to be at once the same and different. He also seems to have read The Economist for the past several centuries, and remembered it. The best I can do, by contrast, is to speak from above the facts and arguments he marshals.

As Fukuyama says, his article and book on the end of history have been relentlessly criticized, but he is too modest to add that they have been universally read. The reason they cannot be ignored or dismissed is that they embody our hopes as well as our doubts, both of which Fukuyama has brilliantly expressed. The "end of history" makes sense of our belief in progress because progress, if it goes toward a better life, must have an end in perfect life. A society that is perfectible must have a perfection. Without an end to history we could never know whether history was going forward, as we believe, or going backward.

Yet an end of history also makes us uncomfortable. It leaves us with nothing interesting to do. Moreover, the path of progress was to have been a way around any set definition of the perfect life, any metaphysical or religious summum bonum. To acknowledge a perfect life at the end of history seems to reinstate the authorities claiming to know that life from which modernity wished to liberate us. When Francis Bacon said that the end of modern science was the "relief of man's estate", he did not tell us what man's estate was. But now, when science does so much for man, we need to know what man is, so that we can tell whether his estate has been relieved or aggravated. It does not matter that we did not start with a notion of the perfect life. We need one now as we approach the destination.

Fukuyama seems to me quite equivocal about the perfection of human life at the end of history. On the one hand he says that the perfect life, with its two elements of economics and esteem--the perfection of the body and the perfection of the soul--has been achieved in liberal democracy. (I exaggerate his words but not his claims.) The fall of communism confirms this truth and events since 1989 do not bring it into doubt. But on the other, he agrees with Nietzsche that humanity is close upon the Last Man--meaning not the best but the disappearance of the best. In this view the idea of progress has led us to disaster. Instead of attaining the perfect life we have lost sight of it.

Fukuyama concentrates his doubts on new developments in biotechnology, particularly on two new drugs, Ritalin and Prozac, illustrating the scary character of modern science. Such drugs may seem capable of creating a "new type of human being." But in fact they simply help to constitute the Last Man, whose definition has been available at least since the early writings of Marx. Ritalin tempers the high spirits of boys, and Prozac raises the low spirits of women. The result is that we will no longer be troubled by psychic sexual differences and all will be equally capable of the same equanimity. Anyway, why would we want to be troubled if, life being perfect, there is nothing to be troubled about?

Fukuyama can see that these drugs contribute to the belittlement, not the esteem, of man. Men are belittled when they do not feel joy or despair, even though, or precisely because, such sentiments are often mistaken or excessive. Nothing great is gained for us if nothing important can be lost. The modern project for reducing risk can be seen at work not only in economics but even in the element of esteem, where it moves us to equalize our chances and to smooth out life's ups and downs. Fukuyama rightly wonders whether, when you take such drugs or other soothing therapy, you are still yourself; or have you given your self away to keep it safe?

The situation gets worse if one were to push Fukuyama to decide whether esteem is really recognition in the Hegelian manner. Hegel conceived that recognition is equal because in recognizing what is other, one recognizes oneself. But if the other is always the alienated self, there is nothing in the universe except the self. Then what are we to say of a life devoted to finding the self that is always ready to abandon the self, that vacillates between desiring recognition and settling for prudent submission?
We know that the modern, well-adjusted self belittles man because we know from religions and philosophies wiser than Hegel that it cannot satisfy human nature. Men cannot be satisfied if there is nothing above them to admire and strive for. At the end of history we may decide to rob ourselves of our humanity, and indeed the most telling charge against American education today is that it gives our children nothing to look up to. But if we do that, it will have been our delusion and our fault.

Harvey Mansfield is professor of government at Harvard University.

E.O. Wilson:

In On Human Nature (1978) I also introduced the theme with which Professor Fukuyama closes his essay, and in Consilience: The Unity of Knowledge (1998) developed it in some detail. I am pleased that a political scientist of Fukuyama's caliber has now arrived independently at the same perception.

But there are differences, and my overall conclusion is a great deal more conservative. In On Human Nature I recognized three successive dilemmas encountered during the growth of scientific materialism. The first dilemma is the sapping of religious and ideological authority, leaving no clear transcendent alternative. The second is the choice to be made among the elements of newly understood human nature--which to constrain and which to enhance. The third dilemma is the one that Professor Fukuyama now recognizes, the choices that will be imposed by volitional evolution of the genetic basis of human nature.

To address the question of volitional evolution, which is on the near horizon of technical capability, it is necessary to define human nature. Fukuyama goes partway when he speaks of the statistical preponderance of hereditary temperament and ability, which is open to genetic fine-tuning. But human nature as newly revealed by cognitive neuroscience and anthropology is something much deeper and more interesting.

In a nutshell, human nature is not the genes that prescribe it. Nor is it the cultural universals, such as incest taboos and rites of passage, which are its products. Rather, human nature is the epigenetic rules, the highly diverse inherited regularities of development in mental traits and their physiological modulators. These rules are the genetic biases in the way our senses perceive the world, the symbolic coding by which we represent the world, the options we open to ourselves, and the responses we find easiest and most rewarding to make. In ways that are beginning to come into focus at the physiological and in a few cases even the genetic level, the epigenetic rules alter the way we see and linguistically classify color. They cause us to evaluate in idiosyncratically human ways the aesthetics of artistic design according to elementary abstract shapes and degree of complexity. They lead us differentially to acquire fears and phobias concerning dangers in the environment (as from snakes and heights), to communicate with certain facial expressions and forms of body language, to bond with infants, to bond conjugally, and so on across a wide range of categories in behavior and thought. Most epigenetic rules are evidently very ancient, dating back millions of years in mammalian ancestry. Others, like the stages of linguistic development in children, are uniquely human and probably only hundreds of thousands of years old. For immense periods of time, they have channeled cultural evolution.

An instructive example of an epigenetic rule is the Westermarck effect, which underlies the instinct to avoid incest. When two people live in close domestic proximity during the first thirty months in the life of either one, both are desensitized to later close sexual attraction and bonding. The Westermarck effect has been well documented in anthropological studies, although the genetic prescription and neurobiological mechanics underlying it remain to be studied. What makes the human evidence the more convincing is that all of the non-human primate species whose sexual behavior has been closely studied also display the Westermarck effect. The rule is thus not just human-specific but primate-specific, and it therefore appears probable that the trait prevailed in the human ancestral line millions of years before the origin of Homo sapiens, our present-day species.

Other examples of epigenetic rules I have cited most recently in Consilience: The Unity of Knowledge illustrate the complexity and depth of human nature as now biologically defined. It may be, as Fukuyama suggests, that in the new world of liberal democracies, free global markets and universal communication, and with genomic technology at their disposal, people will proceed to alter the causal webwork between genes and culture. But red flags are already flying. Let me suggest the risks and provide what I perceive to be the main ethical argument for genetic conservatism.

As the era of volitional evolution approaches, geneticists will warn of fundamental properties in inheritance that greatly complicate the interaction of genes and the environment. One is polygenic inheritance, the control of a single trait by multiple genes at different chromosome sites. While it is true that mutations in one or a small set of master genes have large effects, many other genes have additive effects as well. Some of these effects are epistatic, not just adding to the contribution of others but altering their expression. And finally, there is the near universal occurrence of pleiotropy, the contribution of a single gene to more than one trait.

In sum, in heredity as in the environment, you cannot do just one thing. When a gene is changed by mutation or replaced by another gene, unexpected and possibly unpleasant side effects are likely to follow. Although a complete base pair sequencing and then gene mapping are expected to be completed within a decade, we are probably generations away from a complete genomics--the genetic maps plus all the molecular steps by which the code is read out in final phenotypic traits.

By the time the treacherous waters of possible genomic intervention and replacement are charted, I suspect a moral argument will keep Homo sapiens from traveling there except for gene therapy and minor enhancement. The epigenetic rules--human nature--are not just the algorithms by which individuals are assembled. They are the essence of humanity, the product of millions of years of adaptation to this unique, life-giving planet. They are all we have that separates us from carbon-based all-purpose computers, or transformation into jerrybuilt artifacts. It is one thing to evolve toward taller, brighter, more sociable beings; it is quite another to change or even lose our humanity. In my opinion, human beings will never choose to become posthuman. Professor Fukuyama got it right the first time.

E.O. Wilson is university research professor and honorary curator in entomology at the Museum of Comparative Zoology, Harvard University.