Marriage between close relatives, called incest or incest, is prohibited in all states and is condemned in all cultures as one of the most abhorrent acts.
The ancient Greek myth of Oedipus, the Karelian-Finnish legend of Kullervo - in all these plots, incest appears as a grave sin, incurring a curse, and sometimes not only on the sinner himself, but also on those around him. It is noteworthy that for both heroes incest was not conscious - Oedipus did not know that Jocasta was his mother, Kullervo did not know that he had fallen in love with his sister - but this does not save anyone from retribution.
Modern ban on closely related marriages
The prohibition of incest in the modern world is based on genetic data.
Defective genes that carry deafness, blindness, cystic fibrosis and other congenital pathologies are recessive in most cases. In other words, for such a gene to manifest itself, it must be inherited from both parents. Otherwise, a person is born with a genetic defect, but not sick.
In a family where there is a defective gene, all people are carriers of it. If a man and a woman from such a family marry, the likelihood of having a child with a double defective gene increases dramatically. Of course, in an ordinary marriage, it happens that two carriers of the defective gene meet, but the likelihood of such an event is negligible.
Thus, the prohibition of closely related marriages helps prevent the inheritance of genetic pathologies.
The ancient prohibition of incest
Of course, the ancient people did not know anything about genes and chromosomes, nevertheless, there was a ban on marriage with relatives. This is reminded not only of the already mentioned terrible mythological stories, but also folk tales, where the hero always goes for the bride "to the distant kingdom." Initially, it was about the territory where a foreign family lives - you cannot choose a bride in your family. This custom was called exogamy.
Paradoxically, exogamy did not protect against closely related relationships. If two clans, living in relative proximity to each other, regularly exchange brides for many years, then a representative of a foreign clan may be a cousin to a man, and kinship with a girl from his own clan may be very distant (in the modern world, such relatives may not be known even aristocrats).
Ancient exogamy pursued very different goals. It was designed to eliminate feuds over women within the tribal community. On the other hand, exogamy promoted the establishment of friendly relations between clans, overcame the initial isolation of the ancient clan - after all, exogamy did not appear immediately.
Initially, the ancient clan community was a closed system; people preferred not to deal with other clans. This was the era of endogamy - intrapartum marriages. Her memory is also preserved in folklore and epics. For example, the daughters of the biblical hero Lot come into closeness with their father - and no heavenly punishment befalls them for this, on the contrary, their sons, conceived in such an unnatural way, give rise to two tribes.
Endogamy did not lead to degeneration, because a woman of a kind was not always a native or even a cousin. But in a later era, the custom of endogamy, preserved "at the pinnacle of power," turned into a marriage between brothers and sisters. This was done, for example, by the Egyptian pharaohs - the clan of the "living gods" should not be related to anyone.
A distant echo of such a custom could be observed in some aristocratic families of later times, where even in the 19th century. the tradition of marrying cousins was preserved.
