Closely connected with this question is the more psychological problem of sexual jealousy. The existence of sexual jealousy, especially on the part of the males, has been often referred to by various authors in order to criticize the theories of primitive promiscuity and group marriage. On the other hand, it was pointed out that motives of jealousy are much less strong among some primitive peoples; and many instances have been adduced to prove this assumption. So _e. g._ about the Australians, Spencer and Gillen say: "Amongst the Australian natives with whom we have come in contact, the feeling of sexual jealousy is not developed to anything like the extent to which it would appear to be in many other savage tribes." ... "It is indeed a factor which need not be taken into serious account in regard to the question of sexual relations amongst the Central Australian tribes."[345] [345] _Nat. Tr._, pp. 99, 100. It seems to be beyond any doubt that sexual jealousy, as _we_ conceive it, is completely absent from the aboriginal mind. It has always been a serious defect in ethnological reasoning that such ideas and feelings as those connected with our meaning of "jealousy" have usually not been analyzed, nor the question asked whether they had any meaning and place in a given society, or whether we must assume other corresponding elements to give a new content to the word. Our sexual jealousy--the ideas as well as the feelings involved therein--is moulded by innumerable social factors; it is connected with the notion of honour; it is the result of ideals of pure love, individual sexual rights, sacredness of monogamy, etc. One of the strongest motives is the care for the certainty of physiological fatherhood: paternal affection is strongly enhanced by the idea of blood connection between a man and his offspring. All these factors are obviously either absent or deeply modified in the Australian aboriginal society. It is, therefore, quite wrong to use the word jealousy and ask if it is present among them, without trying to give to it its proper content.