I draw the line at harm, but defining harm can be a slippery matter, too. Human beings are “stomach philosophers”-we allow our gut feelings to make decisions about other people’s sex lives on the basis of whether or not we’re personally disgusted or uncomfortable with their erotic desires or behaviors. The more one learns in this area, paradoxically, the more uncertain one becomes. But if there’s one thing I discovered while working on this book, it’s that the strength of one’s moral convictions about sex usually reflects the depths of one’s ignorance about the science of sex. It’s certainly one of those areas where everyone has an opinion. Why do you think we’re so prone to staunchly believing that how we feel about a sexual behavior is automatically true? One of the themes that comes through is that we feel so sure about the origins and motivations of various sexual behaviors, and for a good many of them there’s no scientific basis for feeling this way – indeed, in many cases science is far from reaching a conclusion.
