1Clinical and cultural materials have demonstrated that three is a symbol of the male genitals. In this case the male genital is considered a unit consisting of three parts: the penis and testicles.

2Different factors that determined this symbolism in a particular patient are discussed. (a) The penis and testicles are in close proximity resulting in the visual perception of a "good Gestalt." (b) The intellectual knowledge that the penis and testicles are anatomically and functionally related leads one to consider them as a unit. (c) My emphasis has been on the role of the similarity of perceptive changes occurring simultaneously in the penis and testicles during sexual excitement in determining the development of the symbol three. I have demonstrated how similar changes take place in penis and testicles—both rise and fall; both become congested and swollen. I have demonstrated that these changes can be perceived through the visceral and somatic sensory nervous systems