Incest

Incest ( ) is human sexual activity between family members or close relatives. This typically includes sexual activity between people in consanguinity (blood relations), and sometimes those related by affinity (marriage or stepfamily), adoption, or lineage. It is strictly forbidden and considered immoral in most societies, and can lead to an increased risk of genetic disorders in children.

The incest taboo is one of the most widespread of all cultural taboos, both in present and in past societies. Most modern societies have laws regarding incest or social restrictions on closely consanguineous marriages. In societies where it is illegal, consensual adult incest is seen by some as a victimless crime. Some cultures extend the incest taboo to relatives with no consanguinity such as milk-siblings, step-siblings, and adoptive siblings, albeit sometimes with less intensity. Third-degree relatives (such as half-aunt, half-nephew, first cousin) on average have 12.5% common genetic heritage, and sexual relations between them are viewed differently in various cultures, from being discouraged to being socially acceptable. Children of incestuous relationships have been regarded as illegitimate, and are still so regarded in some societies today. In most cases, the parents did not have the option to marry to remove that status, as incestuous marriages were, and are, normally also prohibited.

A common justification for prohibiting incest is avoiding inbreeding: a collection of genetic disorders suffered by the children of parents with a close genetic relationship. Such children are at greater risk of congenital disorders, death and developmental and physical disability, and that risk is proportional to their parents' coefficient of relationship—a measure of how closely the parents are related genetically. However, cultural anthropologists have noted that inbreeding avoidance cannot form the sole basis for the incest taboo because the boundaries of the incest prohibition vary widely between cultures and not necessarily in ways that maximize the avoidance of inbreeding.

In some societies, such as those of Ancient Egypt, brother–sister, father–daughter, mother–son, cousin–cousin, aunt–nephew, uncle–niece and other combinations of relations within a royal family were married as a means of perpetuating the royal lineage. Some societies have different views about what constitutes illegal or immoral incest. For example, in Samoa, marriage between a brother and an older sister was allowed, while marriage between a brother and a younger sister was declared as unethical. However sexual relations with a first-degree relative (meaning a parent, sibling or child) are almost universally forbidden.

Terminology

The English word '' incest'' is derived from the Latin ''incestus'', which has a general meaning of "impure, unchaste".
It was introduced into Middle English, both in the generic Latin sense (preserved throughout the Middle English period) and in the narrow modern sense.
The derived adjective ''incestuous'' appears in the 16th century.
Before the Latin term came in, incest was known in Old English as ''sib-leger'' (from ''sibb'' 'kinship' + ''leger'' 'to lie') or ''mǣġhǣmed'' (from ''mǣġ'' 'kin, parent' + ''hǣmed'' 'sexual intercourse') but in time, both words fell out of use. Terms like ''incester'' and ''incestual'' have been used to describe those interested or involved in sexual relations with relatives among humans, while ''inbreeder'' has been used in relation to similar behavior among non-human animals or organisms.

History

Antiquity

In ancient China, first cousins with the same surnames (i.e. those born to the father's brothers) were not permitted to marry, while those with different surnames could marry (i.e. maternal cousins and paternal cousins born to the father's sisters).

Several of the Egyptian Kings married their sisters and had several children with them to continue the royal bloodline. For example Tutankhamun married his half-sister Ankhesenamun and was himself the child of an incestuous union between Akhenaten and an unidentified sister-wife. Several scholars, such as Frier et al., state that sibling marriages were widespread among all classes in Egypt during the Graeco-Roman period. Numerous papyri and the Roman census declarations attest to many husbands and wives being brother and sister, of the same father and mother. However it has also been argued that available evidence does not support the view that such relations were common.

The most famous of these relationships were in the Ptolemaic royal family; Cleopatra VII was married to two of her younger brothers, Ptolemy XIII and Ptolemy XIV, whilst her mother and father, Cleopatra V and Ptolemy XII, were also brother and sister. Arsinoe II and her younger brother, Ptolemy II Philadelphus, were the first in the family to participate in a full-sibling marriage, a departure from custom. A union between children of the same parents was very common in both Greek and Macedonian tradition so it evidently caused some degree of astonishment: the Alexandrian poet Sotades was put to death for criticizing the "wicked" nature of the marriage, while his contemporary Theokritos more politically compared it to the relationship of Zeus with his older sister, Hera. Ptolemy and his sister-wife, Arsinoe, put emphasis on their incestuous union through their mutual adoption of the epithet Philadelphos ("Sibling-Lover"). They were the first full-sibling royal couple in the kingdom's known history to produce a child, Ptolemy V, and for the subsequent century and more the Ptolemies participated in full-sibling unions wherever possible.

It may have been observation of their next-door Ptolemaic competitors that guided the Seleukids to their own experimentations with sibling unions. The daughter of Antiochus III and Laodice III, Laodice IV, married her two full-blooded older brothers, Antiochus and Seleucus IV, and also her younger brother, Antiochus IV. Her second and third brother-husbands ruled as king one after the other, making her the queen in both her marriages. She bore children to all three of her brothers from her union with them. One of them was her son, Demetrius I, who also took the throne at one point and married a full-sister of his own, Laodice V. Laodice V bore her brother-husband three children, and their marriage is the last known sibling marriage in the kingdom's history.

There are records of brother-sister unions in some of the smaller kingdoms of the Hellenistic era, though none of them seems to have pursued it with the zeal and resolve of the Ptolemies. The Pontic and Kommagenian kingdoms had full-sibling unions in a few ages. Mithridates IV of Pontus married his sister Laodice; the couple adopted the double epithet "Philadelphoi", which they publicized on their coinage, where, as Ptolemy II and Arsinoe II, they were depicted in jugate coinage, with the likeness of Hera and Zeus on the back. Mithridates VI Eupator also wed a sister called Laodice. In Commagane the later pro-Roman King Antiochus III Philokaisar wed his sister Iotapa, the couple procreated themselves exactly, producing their son, Antiochus IV Epiphanes, and their daughter, Iotapa, who would unite with him and also adopt the epithet "Philadelphos".

The fable of '' Oedipus'', with a theme of inadvertent incest between a mother and son, ends in disaster and shows ancient taboos against incest, since Oedipus blinds himself in disgust and shame after his incestuous actions. In the ‘sequel’ to Oedipus, '' Antigone'', his four children are also punished for their parents' incestuousness. Incest appears in the commonly accepted version of the birth of Adonis, when his mother, Myrrha, has sex with her father, Cinyras, during a festival, disguised as a prostitute.

In ancient Greece, Spartan King Leonidas I, hero of the legendary Battle of Thermopylae, was married to his niece Gorgo, daughter of his half-brother Cleomenes I. Greek law allowed marriage between a brother and sister if they had different mothers. For example some accounts say that Elpinice was for a time married to her half-brother Cimon.

Incest was sometimes acknowledged as a positive sign of tyranny in ancient Greece. Herodotus recounts a dream of Hippias, son of Pesistratus, in which he "slept with his own mother," and this dream gave him assurance that he would regain power over Athens. Suetonius attributes this omen to a dream of Julius Caesar, explaining the symbolism of dreaming of sexual intercourse with one's own mother.

Incest is mentioned and condemned in Virgil's '' Aeneid'' Book VI: ''hic thalamum invasit natae vetitosque hymenaeos;'' "This one invaded a daughter's room and a forbidden sex act".

Roman civil law prohibited marriages within four degrees of consanguinityPatrick Colquhoun, ''A Summary of the Roman Civil Law, Illustrated by Commentaries on and Parallels from the Mosaic, Canon, Mohammedan, English, and Foreign Law'' (London: Wm. Benning & Co., 1849), p. 513-4 but had no degrees of affinity with regards to marriage. Roman civil laws prohibited any marriage between parents and children, either in the ascending or descending line ''ad infinitum''. Adoption was considered the same as affinity in that an adoptive father could not marry an unemancipated daughter or granddaughter even if the adoption had been dissolved. Incestuous unions were discouraged and considered '' nefas'' (against the laws of gods and man) in ancient Rome. In AD 295 incest was explicitly forbidden by an imperial edict, which divided the concept of ''incestus'' into two categories of unequal gravity: the ''incestus iuris gentium,'' which was applied to both Romans and non-Romans in the Empire, and the ''incestus iuris civilis,'' which concerned only Roman citizens. Therefore, for example, an Egyptian could marry an aunt, but a Roman could not. Despite the act of incest being unacceptable within the Roman Empire, Roman Emperor Caligula is rumored to have had sexual relationships with all three of his sisters (Julia Livilla, Drusilla, and Agrippina the Younger). Emperor Claudius, after executing his previous wife, married his brother's daughter Agrippina the Younger, and changed the law to allow an otherwise illegal union. The law prohibiting marrying a sister's daughter remained. The taboo against incest in ancient Rome is demonstrated by the fact that politicians would use charges of incest (often false charges) as insults and means of political disenfranchisement.

During the first two centuries A.D., in Roman Egypt, full sibling marriage occurred with some frequency among commoners as both Egyptians and Romans announced weddings that have been between full-siblings. This is the only evidence for brother-sister marriage among commoners in any society.

Strabo reported that the Persian magi and the Irish had sex their own mothers. Ctesias' ''History of Persia'' mentions how some Macedonians who saw a performance of ''Oedipus Tyrannus'' were perplexed at why Oedipus felt the need to mutilate himself after learning the truth about his birth; they booed the actor, and urged each other "Go for your mother".

In Norse mythology, there are themes of brother-sister marriage, a prominent example being between Njörðr and his unnamed sister (perhaps Nerthus), parents of Freyja and Freyr. Loki in turn also accuses Freyja and Freyr of having a sexual relationship.

Biblical references

The earliest Biblical reference to incest involved Cain. It was cited that he knew his wife and she conceived and bore Enoch. During this period, there was no other woman except Eve or there was an unnamed sister and so this meant Cain had an incestuous relationship with his mother or his sister. According to the Book of Jubilees, Cain married his sister Awan. Later, in Genesis 20 of the Hebrew Bible, the Patriarch Abraham married his half-sister Sarah. Other references include the passage in Samuel where Amnon, King David's son, raped his half-sister, Tamar. According to Michael D. Coogan, it would have been perfectly all right for Amnon to have married her, the Bible being inconsistent about prohibiting incest.

In Genesis 19:30-38, living in an isolated area after the destruction of Sodom and Gomorrah, Lot's two daughters conspired to inebriate and rape their father due to the lack of available partners to continue his line of descent. Because of intoxication, Lot "perceived not" when his firstborn, and the following night his younger, daughter lay with him.

Moses was also born to an incestuous marriage. Exodus 6 detailed how his father Amram was the nephew of his mother Jochebed. An account noted that the incestuous relations did not suffer the fate of childlessness, which was the punishment for such couples in levitical law. It stated, however, that the incest exposed Moses "to the peril of wild beasts, of the weather, of the water, and more."

From the Middle Ages onward

Many European monarchs were related due to political marriages, sometimes resulting in distant cousins – and even first cousins – being married. This was especially true in the Habsburg, Hohenzollern, Savoy, and Bourbon royal houses. However, relations between siblings, which may have been tolerated in other cultures, were considered abhorrent. For example, the false accusation that Anne Boleyn and her brother George Boleyn had committed incest was one of the reasons given for both being executed in May 1536. Historians agree that the false accusation against Anne Boleyn and George Boleyn was trumped up in order to ensure the king could go on to marry Jane Seymour.

Incestuous marriages were also seen in the royal houses of ancient Japan and Korea, Inca Peru, Ancient Hawaii, and, at times, Central Africa, Mexico, and Thailand. Like the kings of ancient Egypt, the Inca rulers married their sisters. Huayna Capac, for instance, was the son of Topa Inca Yupanqui and the Inca's sister and wife.

The ruling Inca king was expected to marry his full sister. If he had no children by his eldest sister, he married the second and third until they had children. Preservation of the purity of the Sun's blood was one of the reasons for the brother-sister marriage of the Inca king. The Inca kings claimed divine descent from celestial bodies, and emulated the behavior of their celestial ancestor, the Sun, who married his sister, the Moon. Another reason the princes and kings married their sisters was so the heir might inherit the kingdom as much as through his mother as through his father. Therefore, the prince could invoke both principles of inheritance.

Half-sibling marriages were found in ancient Japan such as the marriage of Emperor Bidatsu and his half-sister Empress Suiko. Japanese Prince Kinashi no Karu had sexual relationships with his full sister Princess Karu no Ōiratsume, although the action was regarded as foolish. In order to prevent the influence of the other families, a half-sister of Korean Goryeo dynasty monarch Gwangjong became his wife in the 10th century. Her name was Daemok. Marriage with a family member not related by blood was also regarded as contravening morality and was therefore incest. One example of this is the 14th century Chunghye of Goryeo, who raped one of his deceased father's concubines, who was thus regarded to be his mother.

In India, the largest proportion of women aged 13 to 49 who marry their close relative are in Tamil Nadu, then Andhra Pradesh, Karnataka, and Maharashtra. While it is rare for uncle-niece marriages, it is more common in Andhra Pradesh and Tamil Nadu.

Others

In some Southeast Asian cultures, stories of incest being common among certain ethnicities are sometimes told as expressions of contempt for those ethnicities.

Marriages between younger brothers and their older sisters were common among the early Udege people.

In the Hawaiian Islands, high ''ali'i'' chiefs were obligated to marry their older sisters in order to increase their ''mana''. These copulations were thought to maintain the purity of the royal blood. Another reason for these familial unions was to maintain a limited size of the ruling ''ali'i'' group. As per the priestly regulations of Kanalu, put in place after multiple disasters, "chiefs must increase their numbers and this can be done if a brother marries his older sister."

Prevalence and statistics

Incest between an adult and a person under the age of consent is considered a form of child sexual abuse that has been shown to be one of the most extreme forms of childhood abuse; it often results in serious and long-term psychological trauma, especially in the case of parental incest. Its prevalence is difficult to generalize, but research has estimated 10–15% of the general population as having at least one such sexual contact, with less than 2% involving intercourse or attempted intercourse. Among women, research has yielded estimates as high as 20%.

Father– daughter incest was for many years the most commonly reported and studied form of incest. More recently, studies have suggested that sibling incest, particularly older brothers having sexual relations with younger siblings, is the most common form of incest, with some studies finding sibling incest occurring more frequently than other forms of incest. Some studies suggest that adolescent perpetrators of sibling abuse choose younger victims, abuse victims over a lengthier period, use violence more frequently and severely than adult perpetrators, and that sibling abuse has a higher rate of penetrative acts than father or stepfather incest, with father and older brother incest resulting in greater reported distress than stepfather incest. South Africa, Saudi Arabia, Sudan, Pakistan and Nigeria are some of the countries with the most incest through consanguineous marriage.

Types

Between adults and children

Sex between an adult family member and a child is usually considered a form of child sexual abuse, also known as child incestuous abuse, and for many years has been the most reported form of incest. Father–daughter and stepfather–stepdaughter sex is the most commonly reported form of adult–child incest, with most of the remaining involving a mother or stepmother. Many studies found that stepfathers tend to be far more likely than biological fathers to engage in this form of incest. One study of adult women in San Francisco estimated that 17% of women were abused by stepfathers and 2% were abused by biological fathers. Father–son incest is reported less often, but it is not known how close the frequency is to heterosexual incest because it is likely more under-reported. Prevalence of incest between parents and their children is difficult to estimate due to secrecy and privacy.

In a 1999 news story, BBC
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