Oedipus complex
Penis envy stems from Freud's concept of the Oedipus complex in which the phallic conflict arises for males, as well as for females. Though Carl Jung made the distinction between the Oedipus Complex for males and the Electra Complex for females in his work "The Theory of Psychoanalysis", Freud rejected this latter term, stating that the feminine Oedipus complex is not the same as the male Oedipus because, "It is only in the male child that we find the fateful combination of love for the one parent and simultaneous hatred of the other as a rival." This development of the female Oedipus complex according to Freud begins when the female makes comparisons with another male, perceiving this not as a sex characteristic; but rather, by assuming that she had previously possessed a penis, and had lost it by castration. This leads to the essential difference between the male and female Oedipus complex that the female accepts castration as a fact, while the boy fears it happening.