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Like much of Richard Posner's best work, Sex and Reason does many things, and for that reason will no doubt attract a large and diverse readership. This heavily footnoted, exhaustively researched, and imminently accessible book is a welcome introduction to the interdisciplinary study of sex. For the lay reader it presents an arresting set of speculations about human sexuality, drawn from the author's evident familiarity with a sizeable library of studies representing at least half a dozen scientific and social scientific disciplines, assembled in a readable and lively way. Of more interest, perhaps, to academicians and social scientists familiar with the literature, the book also proposes an ambitious, counter-intuitive, and sure to be controversial sociobiological argument about the essential nature of sexuality. This argument aims to account for both the universality of some sexual behaviors, on the one hand, and the extraordinary diversity of sexual customs, beliefs, and practices, on the other.

Sex and Reason is an attempt by our most prominent rationalist to prove the absolute universality of economic reasoning in human choice and behavior by showing the rationality of our presumably most irrational choices and behaviors: those driven by our sexual urges. Thus, as the author states in his opening remarks, the large purpose of this book is to explain the rationality of our sexual behavior, and thereby limit, if not disprove the Aristotelian dictum, quoted in the book's opening epigram, that "[Sexual] pleasures are an impediment to rational deliberation, . . . it is impossible to think about anything while absorbed in them." The author's main target, in other words, is neither liberal nor conservative moralism, but rather the widespread intuition, shared by academicians, legislators, and the lay public alike, that whatever the value of economic reasoning in commercial and maybe even some noncommercial spheres of life, it certainly has no relevance -- no explanatory power -- in controlling behavior and choices so thoroughly irrational -- so emotional, instinctive, biological -- as our sexual inclinations and drives. On the contrary, Posner insists, although forces beyond our control heavily determine our sexual preferences, this hardly distinguishes them from other preferences that are similarly given rather than chosen. Accordingly, the determinism of our sexual preferences hardly disqualifies them from the benefit of dispassionate study and control by the trained economist's eye.

I argue in this review that although Posner's descriptive claim about the rationality of our sexual behavior does indeed have an odd ring to it, it is Posner's normative claims -- his rigid insistence on dispassion and neutrality in the study and regulation of sexual choice -- that is ultimately the Achilles' heel of this book. It becomes quickly apparent on even a casual reading that Posner's insistence on moral neutrality goes well beyond his liberal sounding tolerance of deviant sexual preferences and practices. Rather, the moral neutrality Posner advocates requires a studied moral apathy toward a bewildering array of practices, customs, habits, and inclinations that cause inestimable amounts of human suffering and reveal the existence of manifest unjust subordination of large groups of persons -- primarily, women. I suggest that moral neutrality is not the attitude we ought to take toward such behaviors, as either scientists or legislators.

Publication Citation

81 Geo. L.J. 2413 (1993)