There is a tendency to consider anything in human behavior that is unusual, not well known, or not well understood, as neurotic, psychopathic, immature, perverse, or the expression of some other sort of psychologic disturbance.

Only the human mind invents categories and tries to force facts into separated pigeonholes.

Art alone develops weaklings, science alone, monsters. Somewhere, somehow, we must combine the two.

The very general occurrence of the homosexual in ancient Greece, and its wide occurrence today in some cultures in which such activity is not taboo suggests that the capacity of an individual to respond erotically to any sort of stimulus, whether it is provided by another person of the same or opposite sex, is basic in the species.

The only unnatural sex act is that which you cannot perform.

If biologists so often forget the most universal of all biologic principles [variation], it is not surprising that men and women in general expect their fellows to think and behave according to the pattern that may fit the law-maker, or the imaginary ideals for which the legislation was fashioned, but which are ill-shaped for all real individuals who try to live under them.

The male's difficulties in his sexual relations after marriage include a lack of facility, of ease, or of suavity in establishing rapport in a sexual situation.