Ah, sex -- "the most mysterious, misunderstood and rewarding of human functions," as TIME wrote in 1970. The subject then was Masters and Johnson's book Human Sexual Inadequacy, one of four studies of Americans' sex habits to which TIME has devoted cover stories. The others: Alfred Kinsey's Sexual Behavior in the Human Female (1953), Shere Hite's Woman and Love, a Cultural Revolution in Progress (1987) and The Social Organization of Sexuality, the University of Chicago study that is the subject of this week's cover.
Kinsey had some shocking news for mid-century America: women enjoy sex. In the cover story Henry Anatole...