Electra complex classical psychoanalytic theory, the child's identification with the same-sex parent is the successful resolution of the Electra complex and of the Oedipus complex; his and her key psychological experience to developing a mature sexual role and identity. Sigmund Freud instead proposed that girls and boys resolved their complexes differently—she via penis envy, he via castration anxiety; and that unsuccessful resolutions might lead to neurosis. Hence, women and men who are fixated in the Electra and Oedipal stages of their psychosexual development might be considered "father-fixated" and "mother-fixated". As a psychoanalytic term for daughter–mother psychosexual conflict, the Electra complex derives from
Oedipus complex not such a post-Lacanian interpretation "stretches the Oedipus complex to a point where it almost doesn't look like Freud's any more". Parent-child and sibling-sibling incestuous unions are almost universally forbidden. An explanation for this incest taboo is that rather than instinctual sexual desire, there is instinctual sexual aversion against these unions (See Westermarck effect). Steven Pinker wrote that "The idea that boys want to sleep with their mothers strikes most men as the silliest thing they have ever heard. Obviously, it did not seem so to Freud, who wrote that as a boy he once had an erotic reaction to