[17] Macdonald, Oceania, p. 181 sq.
[18] Kubary, ‘Die Bewohner der Mortlock Inseln,’ in Mittheil. d. Geogr. Gesellsch. in Hamburg, 1878-9, p. 251.
[19] Westermarck, op. cit. p. 299 sq. See, besides the authorities quoted there, Roth, Ethnol. Studies among the North-West-Central Queensland Aborigines, p. 182; Spencer and Gillen, Native Tribes of Central Australia, p. 15.
Not less intense is the horror of incest among nations that have passed beyond savagery and barbarism. Among the Chinese incest with a grand-uncle, a father’s first cousin, a brother, or a nephew, is punishable by death, and a man who marries his mother’s sister is strangled; nay, punishment is inflicted even on him who marries a person with the same surname as his own, sixty blows being the penalty.[20] So also incest was held in the utmost horror by the so-called Aryan peoples in ancient times.[21] In the ‘Institutes of Vishnu’ it is said that sexual intercourse with one’s mother or daughter or daughter-in-law is a crime of the highest degree, for which there is no other atonement than to proceed into the flames.[22]
[20] Medhurst, ‘Marriage, Affinity, and Inheritance in China,’ in Trans. Roy. Asiatic Soc. China Branch, iv. 21 sqq.
[21] Leist, Alt-arisches Jus Gentium, p. 394 sq.
[22] Institutes of Vishnu, xxxiv. 1 sq.
Various theories have been set forth to account for the prohibition of marriage between near kin. I criticised some of them in my book on the ‘History of Human Marriage,’ and ventured at the same time on an explanation of my own.[23] I pointed out that there is an innate aversion to sexual intercourse between persons living very closely together from early youth, and that, as such persons are in most cases related by blood, this feeling would naturally display itself in custom and law as a horror of intercourse between near kin. Indeed, an abundance of ethnographical facts seem to indicate that it is not in the first place by the degree of consanguinity, but by the close living together, that prohibitory laws against intermarriage are determined. Thus many peoples have a rule of “exogamy” which does not depend on kinship at all, but on purely local considerations, all the members of a horde or village, though not related by blood, being forbidden to intermarry.[24] The prohibited degrees are very differently defined in the customs or laws of different nations, and it appears that the extent to which relatives are prohibited from intermarrying is nearly connected with their close living together. Very often the prohibitions against incest are more or less one-sided, applying more extensively either to the relatives on the father’s side or to those on the mother’s, according as descent is reckoned through men or women. Now, since the line of descent is largely connected with local relationships, we may reasonably infer that the same local relationships exercise a considerable influence on the table of prohibited degrees. However, in a large number of cases prohibitions of intermarriage are only indirectly influenced by the close living together.[25] Aversion to the intermarriage of persons who live in intimate connection with one another has called forth prohibitions of the intermarriage of relations; and, as kinship is traced by means of a system of names, the name comes to be considered identical with relationship. This system is necessarily one-sided. Though it will keep up the record of descent either on the male or female side, it cannot do both at once;[26] and the line which has not been kept up by such means of record, even where it is recognised as a line of relationship, is naturally more or less neglected and soon forgotten. Hence the prohibited degrees frequently extend very far on the one side—to the whole clan—but not on the other. It should also be remembered that, according to primitive ideas, the name itself constitutes a mystic link between those who have it in common. “In Greenland, as everywhere else,” says Dr. Nansen, “the name is of great importance; it is believed that there is a spiritual affinity between two people of the same name.”[27] Generally speaking, the feeling that two persons are intimately connected in some way or other may, through an association of ideas, give rise to the notion that marriage or sexual intercourse between them is incestuous. Hence the prohibitions of marriage between relations by alliance and by adoption. Hence, too, the prohibitions of the Roman and Greek Churches on the ground of what is called “spiritual relationship.”
[23] Westermarck, op. cit. p. 310 sqq.
[24] Herr Cunow (Die Verwandtschafts-Organisationen der Australneger, p. 187) finds this argument “rather peculiar,” and offers himself a different explanation of the rule in question. He writes:—“In der Wirklichkeit erklärt sich das Verbot einfach daraus, dass sehr oft die Lokalgruppe mit dem Geschlechtsverband beziehungsweise dem Totemverband kongruirt, und demnach das was für die Gens gilt, zugleich auch für die Lokalgruppe Geltung hat.” This, however, is only Herr Cunow’s own inference. And it may be asked why it is more “peculiar” to suppose that the prohibition of marriage between near kin has sprung from aversion to sexual intercourse between persons living closely together, than to assume that the rule which forbids marriage between unrelated persons living in the same community has sprung from the prohibition of marriage between kindred.