At first, in art, the sex organs were represented by pictures of them, but as man developed and ideas of morals changes, such representations seemed offensive or crude, and they were therefore gradually modified until the symbols could scarcely be recognized as sexual in origin. Other explanations and meanings where invented for the masses, who were no supposed to understand the true meanings. Thus, symbols came to have two meanings, the esoteric and the exoteric. - Charles G. Berger