The childhood-familiarity theory, suggested by Edward Westermarck, was given a wide hearing in the early 1920s. Westermarck argued that people who have been closely associated with each other since earliest childhood, such as siblings, are not sexually attracted to each other and would therefore avoid marriage with each other.49 This theory was rejected upon the subsequent discovery that some children were sexually interested in their parents and siblings. More recent studies have suggested, however, that there might be something to Westermarck’s theory.
Yonina Talmon investigated marriage patterns among the second generation of three well-established collective communities ( kibbutzim) in Israel. In these collectives, children live with many members of their peer group in quarters separate from their families. They are in constant interaction with their peers from birth to maturity. The study among 125 couples revealed that, despite parental encouragement of marriage within the peer group, there was “not one instance in which both mates were reared from birth in the same peer group.”50 Children reared in common not only avoided marriage, they also avoided any sexual relations among themselves.
Talmon reported that the people reared together firmly believed that overfamiliarity breeds sexual disinterest. As one of them told her, “We are like an open book to each other. We have read the story in the book over and over again and know all about it.”51 Talmon’s evidence reveals not only the onset of disinterest and even sexual antipathy among children reared together but a correspondingly heightened fascination with newcomers or outsiders, particularly for their “mystery.”
Arthur Wolf’s study of the Chinese in northern Taiwan also supports the idea that something about being reared together produces sexual disinterest. Wolf focused on a community still practicing the Chinese custom of t’ung-yang-hsi,or “daughter-in-law raised from childhood”:
When a girl is born in a poor family . . . she is often given away or sold when but a few weeks or months old, or one or two years old, to be the future wife of a son in the family of a friend or relative which has a little son not betrothed in marriage. . . . The girl is called a “little bride” and taken home and brought up in the family together with her future husband.52
Wolf’s evidence indicates that this arrangement is associated with sexual difficulties when the childhood “couple” later marry. Informants implied that familiarity caused the couple to be disinterested and to fail to be stimulated by one another. Such couples produce fewer offspring than spouses who are not raised together, are more likely to seek extramarital sexual relationships, and are more likely to get divorced.53
The Talmon and Wolf findings are consistent with Westermarck’s belief that the incest taboo may indicate avoidance more than it does a prohibition of certain matings. Another study, undertaken by Hilda and Seymour Parker, that may be consistent with Westermarck’s explanation of the incest taboo compared two groups of fathers: those who had allegedly sexually abused their daughters and those who had not.54 To maximize the similarities among the men in their test group, the Parkers selected the fathers from the same prisons and psychiatric facilities. The Parkers found that the fathers who had committed incest with their daughters were much more likely to have had little involvement with bringing up their daughters; they were not at home or rarely at home during the daughters’ first three years of life. The fathers who avoided incest had been more closely involved with their daughters’ early childhood.
Although Westermarck’s theory suggests that sexual aversion develops during early childhood, some researchers have asked whether the childhood familiarity theory could explain the extension of incest taboos to first cousins. The familiarity argument would imply that first-cousin marriage should be prohibited in societies where first cousins grow up in the same community. However, such societies are not more likely to prohibit first-cousin marriage.55
Even if it is likely that familiarity in childhood normally leads to sexual disinterest,56 we must ask why societies need to prohibit marriages that would voluntarily be avoided because of disinterest. And if familiarity breeds disinterest, what are we to make of couples who remain actively interested in each other sexually after years of marriage?