Incest is the prohibited sexual relations between members of a close kinship group, such as parents and children or brothers and sisters. The term includes actual intercourse and other sexual acts, such as touching, self-exposure, masturbating, and posing for pictures.

Although the incest taboo is almost universal, notions of kinship vary greatly from culture to culture. Some cultures would consider sexual relations between first cousins incest, whereas others would not. The same premise holds true for intercourse between a stepfather and stepdaughter. The very rare exceptions to incest, such as those found in ancient Egyptian and Incan societies, usually involve mandatory incestuous unions within royal families, which may have been motivated by economic or theocratic considerations.

In classical psychoanalytic theory, the development of children between three and five years of age is characterized by naturally incestuous desires toward the parent of the opposite sex. Sigmund Freud called these desires in males the Oedipus complex, referring to the accidental incest between the title character and his mother in the classical Greek tragedy, Oedipus Rex. Freud asserted that young boys form a sexual attachment to their mothers, accompanied by resentment and hostility toward their fathers, whom they regard as rivals for their mother's attention. The fear of retaliation by the father, which takes the form of castration anxiety, leads the boy to renounce his forbidden desire for his mother and identify with his father. Thus, a boy assumes his proper gender identity and gains a superego (conscience) composed of his father's moral values.

Freud's colleague Carl Jung (1875–1961) posited roughly the same condition, in reverse, for girls. He called this the Electra complex, based on the title character in Sophocles’ play. The widespread existence of incestuous desire appears irrefutable; many theorists claim it is demonstrated by the very universality of the incest taboo. Contemporary psychologists, however, differ widely about the nature and developmental importance of incestuous feelings.

Among the various types of incest, sexual relations between brother and sister and between father and daughter occur more frequently than mother-son incest. Incest takes place within a broad spectrum of relationships; perpetrators of incest can be aunts, uncles, cousins, nieces, nephews, step-parents, stepchildren, grandparents, or grandchildren. Perpetrators of incest do not always have a direct blood or legal relationship to the victim. A parent's lover or live-in babysitter may perpetrate incest. The phenomenon of covert incest has also been noted in families; a mother may act toward her son in a sexualized manner without actually seducing him. Often other members of the family are aware of an incestuous relationship, and this family secret governs the psychodynamics of the entire family structure. According to reports by incest survivors, most child sexual abuse is committed by male relatives who have a history of psychological problems and emotional deprivation. Fathers often start an incestuous relationship with more than one daughter. In many cases, the mother is aware of the abuse, but feels powerless to stop it or colludes with the father for reasons of her own.

See also Child abuse ; Dysfunctional family ; Freud, Sigmund; Jung, Carl; Oedipus complex ; Psychosexual stages ; Sexual abuse .



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Maisch, Herbert. Incest. New York: Stein and Day, 1972.

Wolf, Arthur P. Incest Avoidance and the Incest Taboos: Two Aspects of Human Nature. Stanford, CA: Stanford University Press, 2014.


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