The American Philosophical Society, Oxford University Press and Smith College seem far removed from the mass appeal of Cosmopolitan, the trashy women’s magazine that glorifies sex, career and the unremittingly plunging neckline. But, in a world in which discriminating taste is non-discriminating, whatever is popular must be good. Oxford, you see, is the publisher of Jennifer Scanlon's recently-released Bad Girls Go Everywhere, the biography of Cosmo’s former editor, the jet-setting Helen Gurley Brown, famous for saying "Good girls go to heaven; bad girls go everywhere." The philosophical society provided research funding to Scanlon, a professor at Bowdoin College. She did her historical digging among the treasured Helen Gurley Brown Papers at Smith.  These estimable archives must include at least some of Cosmo’s vast stores of semi-pornographic cover photos, as well as precious manuscripts of Sex and the Single Girl, Brown’s best-selling 1962 book that helped single women adjust to a life of promiscuity and raw ambition, paving the way for Carrie Bradshaw. In the book, Brown called the housewife and mother a “parasite, a dependent, a scrounger, a sponger … a bum.”   Brown grew up poor in Arkansas, a fact which apparently excuses naked ambition and greed. For a time, it seemed the young girl was destined to a life of what Scanlon calls “gender conformity.”  Instead, she discovered the stupendously fulfilling vistas of the workaholic office drudge and passed on her enthusiasm for being single and carefree. Scanlon includes interesting insights into the period of Brown’s ascendancy, a time…