1948, January: The Kinsey report on sexual activity in human males
Among the varios statements in the influential Kinsey Report is the following:
Males do not represent two discrete populations, homosexual and heterosexual. The world is not to be divided into sheep and goats. Not all things are black nor all things white .... Only the human mind invents categories to force facts into separate pigeonholes. The living world is a continuum in each and every one of its aspects. The sooner we learn this concerning human sexual behavior the sooner we shall reach a sound understanding of the realities of sex.
NOTE:
Alfred C. Kinsey, Wardell B. Pomeroy, Clyde E. Martin. Sexual Behavior in the Human Male. (Philadelphia: Saunders, January 1948), 639.