Blumenfeld's thesis--much too presumptuous a word--is that the decline in the birth rate (and rise in the divorce rate) has led to indiscriminate sex, crime, suicide, gonorrhea and abortion. Much of it is due to spokeswomen like de Beauvoir and Caroline Bird (who coined the phrase ""alternative investments"" of women's energy which Blumenfeld so deplores) and the all too familiar exponents of Women's Lib. Parents' Magazine has fallen off while women read Cosmo and Playgirl. On the other hand if men have lost their clout, it's because they ""can no longer stand the strain and tension of trying to control women."" It's true that ""sexual and emotional compatability are the exception rather than the rule"" and that marriage requires ""self-sacrifice""--so stop writing to Dear Abby; that ""sex, as everyone knows, was invented by nature to facilitate the reproduction of the species""; and that ""men are attracted to women because of their maternal capabilities."" Blumenfeld has read most of the popular literature and discounts all scientific opinion (re zero population growth, the economics of financing a family, etc.) so publish and perish, increase and multiply.