Let us now turn to inquire how far it is possible to explain these features of Melanesian systems of relationship by psychological similarity. If it were not for the cross-cousin marriage, what can there be to give the mother's brother a greater psychological similarity to the father-in-law than the father's brother, or the father's sister a greater similarity to the mother-in-law than the mother's sister? Why should it be two special kinds of cousin who are classed with two special kinds of brother- and sister-in-law or with the husband or wife? Once granted the presence of the cross-cousin marriage, and there are psychological similarities certainly, though even here the matter is not quite straightforward from the point of view of the believer in their importance, for we have to do not merely with the similarity of two relatives, but with their identity, with the combination of two or more relationships in one and the same person. Even if we put this on one side, however, it remains to ask how it is possible to say that terms of relationship do not reflect sociology, if such psychological similarities are themselves the result of the cross-cousin marriage? What point is there in bringing in hypothetical psychological similarities which are only at the best intermediate links in the chain of causation connecting the terminology of relationship with antecedent social conditions?
If you concede the causal relation between the characteristic features of a Fijian or Anaiteum or
