Dr. Freud determined the libido controls man’s nature. He thought the male child was engaged in a constant struggle to overcome his father in order to claim his mother and demonstrate his power in the world. He said he figured this out because of his own attraction to his mother and jealousy of his father and if it was the case for him it must be the case for everybody.
The female child, meanwhile, was in envy of male potency as symbolized by the male genitalia. I guess he was saying we are all controlled by our physical bodies and our minds simply respond to our animal natures.
Dr. Freud must have thought about sex quite a bit; he ended up having six children.