A titillating title (from Jacques PrÃ‰vert) for a tedious text. This is the same old Fox of The Imperial Animal, etc., spouting forth on the primordial horde, on the human mind forming out of hunting and gathering, and on cultures forming around kinship alliances and power hierarchies (in particular, the power of old males to monopolize young females). The natural pattern of culture, according to Fox, is that of older male blocks, young female blocks, and women-offspring blocks; the blocks each want something from the other, and trading off is the rule. What all this has to do with incest is that in most cultures, at most times--Fox says--incest is not much sought after and not a very profitable sexual alternative. Rather than invoke an anti-incest ""instinct,"" however, he suggests that there is an evolutionary ""readiness to learn"" anti-incest behavior. He quotes the now-familiar query about why anyone would want to sleep with his sister and risk losing a brother-in-law (or two). He quotes Freud, on totem and taboo, and on Oedipus and ambivalence: incest is both the strongest desire and the most sternly punished. He tries to reconcile Freud with the Swedish thinker, Edward Westermarck, who theorized that the closer the relations between the sexes in childhood, the greater would be their sexual aversion in maturity. And, in indiscriminate abandon, he quotes countless other ethnographers, behavioral scientists, and littÃ‰rateurs. By the close, he has also managed to inject his usual controversial commentaries on contemporary society, e.g., on feminism: ""Taken to its extreme, the militant position seems to suggest that if Hitler and his cronies had all been women, Nazism would have been just fine."" Or, on teenage pregnancy: ""The U.S.A. can then be seen. . . as once more leading the way back to normality; that is, first pregnancy being teenage."" Bluster.