In this essay I examine a well-known articulation of human nature skepticism, a paper by Hull. I then review a recent reply to Hull by Machery, which argues for an account of human nature that he claims is both useful and scientifically robust. I challenge Machery’s account and introduce an alternative account—the “life-history trait cluster” conception of human nature—that I hold is scientifically sound and makes sense of our intuitions about—and desiderata for—human nature.

Abstract The only biologically respectable notion of human nature is an extremely permissive one that names the reliable dispositions of the human species as a whole. This conception offers no ethical guidance in debates over enhancement, and indeed it has the result that alterations to human nature have been commonplace in the history of our species. Aristotelian conceptions of species natures, which are currently fashionable in meta-ethics and applied ethics, have no basis in biological fact. Moreover, because our folk psychology (...) finds this misleading Aristotelian conception highly tempting, we are in fact better off if we refrain from mentioning human nature altogether in debates over enhancement. Content Type Journal Article Category Special Issue Pages 1-16 DOI 10.1007/s13347-012-0063-x Authors Tim Lewens, Department of History and Philosophy of Science, University of Cambridge, Free School Lane, Cambridge, CB2 3RH UK Journal Philosophy & Technology Online ISSN 2210-5441 Print ISSN 2210-5433. (shrink)

Many philosophers invoke the "wisdom of nature" in arguing for varying degrees of caution in the development and use of genetic enhancement technologies. Because they view natural selection as akin to a master engineer that creates functionally and morally optimal design, these authors tend to regard genetic intervention with suspicion. In Part II, we examine and ultimately reject the evolutionary assumptions that underlie the master engineer analogy (MEA). By highlighting the constraints on ordinary unassisted evolution, we show how intentional genetic (...) modification can overcome many of the natural impediments to the human good. Our contention is that genetic engineering offers a solution that is more eff icient, reliable, versatile, and morally palatable than the lumbering juggernaut of Darwinian evolution. In Part III, we evaluate a recent attempt to ground precautionary enhancement heuristics in adaptive etiology. Our problem with this approach is two-fold: first, it is based on the same "strong adaptationist" interpretation of evolution that motivates the flawed MEA, and second, the etiological concept of function on which it relies provides indirect and potentially misleading information about the likely consequences of genetic intervention. We offer instead enhancement criteria based on causal relationships in ontogeny. We conclude that rather than grounding a presumption against deliberate genetic modification, the causal structure of the living world gives us good moral reason to pursue it. (shrink)

Philosophers of biology, such as David Hull and Michael Ghiselin, have argued that the notion of human nature is incompatible with modern evolutionary biology and they have recommended rejecting this notion. In this article, I rebut this argument: I show that an important notion of human nature is compatible with modern evolutionary biology.

Appeals to the idea of human nature are frequent in the voluminous literature on the ethics of enhancing human beings through biotechnology. Two chief concerns about the impact of enhancements on human nature have been voiced. The first is that enhancement may alter or destroy human nature. The second is that if enhancement alters or destroys human nature, this will undercut our ability to ascertain the good because, for us, the good is determined by our nature. The first concern assumes (...) that altering or destroying human nature is in itself a bad thing. The second concern assumes that human nature provides a standard without which we cannot make coherent, defensible judgments about what is good.I will argue (1) that there is nothing wrong, per se, with altering or destroying human nature, because, on a plausible understanding of what human nature is, it contains bad as well as good characteristics and there is no reason to believe that eliminating some of the bad would so imperil the good as to make the elimination of the bad impermissible, and (2) that altering or destroying human nature need not result in the loss of our ability to make judgments about the good, because we possess a conception of the good by which we can and do evaluate human nature. I will argue that appeals to human nature tend to obscure rather than illuminate the debate over the ethics of enhancement and can be eliminated in favor of more cogent considerations. (shrink)