Sex and Reason
Posner, Richard A. 1994. Sex and Reason. Harvard University Press.
Sex and Reason is basically a liberal, rational choice theorists effort to explain both why people behave the way they do sexually and to justify why most sexual behavior should be considered perfectly acceptable. The book covers a wide range of topics, include: theories about sex, a history of sex and sexual mores, the biology of sex, the morality of sex, regulation of sex and marriage, homosexuality, pornography, rape and sexual abuse, adoption, artificial insemination, and sex and the courts.
In many ways this book succeeds. The historical analysis, while of necessity brief and somewhat superficial, offers a good grounding for anyone interested in how sexuality has changed over time. Also, the connection of sex to the courts and the law is an aspect of sexuality that I had not thought about as deeply as this book forces one to do.
Where I have serious reservations with the book is in the primary choice of theory: rational choice theory. Rational choice theory is rooted in the idea that all people are rational actors who attempt to behave in fundamentally rational ways. Both of those assertions are likely to be flawed, depending on how you define “rational”. If, as many rational choice theorists do, you define rational tautologically as whatever people choose to do is rational, then you have a theory of, well, nothing. Such a theory fails to predict anything. If you hold to a more rigorous definition of rational, as something along the lines of behavior that maximizes what most people would consider to be benefits and minimizes what most people consider to be negatives, you likely could explain some human behavior, but there will be many instances of human behavior that run counter to your theories. Why? Because humans are only partially rational and don’t always behave in rational ways.
This theoretical approach basically results in a book in which the author’s particularly perspective can never be wrong, as rational choice theorists can always find a way to explain why something is happening or should happen. There are no instances in this book when rational choice theory fails to predict sexual behaviors, which suggests that the theory is either perfect or that the theory is so flawed that it can be easily manipulated to make it seems as thought it is perfect by predicting behavior ex post facto. Such a theory, then, offers little in the way of predicting human behavior.
Overall, it’s hard to be critical of a book that tries very hard to justify many of the beliefs I hold. However, the theoretical approach is so flawed as be frustrating for the discriminating reader who sees the tautological problems in most of the explanations provided. The book is somewhat redeeming when it comes to its superficial historical treatments of sexuality and its legal analysis.