Unfruitful” Intercours
Nor should we overlook the fact that human sex organs may be and are used to express, in the deepest and most intimate way open to man, the love of one person for another. Even the most ardent opponents of “unfruitful” intercourse admit that sex does serve this function. They have accordingly conceded that a man and his wife may have intercourse even though she is pregnant, or past the age of child bearing, or in the infertile period of her menstrual cycle. . . .
To sum up, then, the proposition that any use of an organ that is contrary to its principal purpose or function is unnatural assumes that organs have a prin- cipal purpose or function, but this may be denied on the ground that the pur- pose or function of a given organ may vary according to the needs or desires of its owner. It may be denied on the ground that a given organ may have more than one principal purpose or function, and any attempt to call one use or another the only natural one seems to be arbitrary, if not question-begging. Also, the proposition suggests that what is unnatural is evil or depraved. This goes beyond the pure description of things, and enters into the problem of the evaluation of human behavior, which leads us to the fifth meaning of natural.
