The polarity between the male and female principles exists also within each man and each woman. Just as physiologically man and woman each have hormones of the opposite sex, they are bisexual also in the psychological sense. They carry in themselves the principle of receiving and of penetrating, of matter and of spirit. Man—and woman—finds union within himself only in the union of his female and his male polarity. This polarity is the basis for all creativity.
Erich Fromm, The Art of Loving
philosophy, psychology