As to brother and sister avoidance, if there is an 'instinct,' as Westermarck thinks, against marriage between near relations, if 'close living together inspires an aversion to intermarriage' (pp. 352, 545), then the avoidance of brother and sister would make them especially apt to fall in love together. But they don't. Brother and sister, under the tabu, are the greatest possible strangers to each other. They have not 'lived in long-continued intimate relationship from a period of life at which the action of desire is out of the question' (Westermarck, p. 353). They have done precisely the reverse. So why they do not fall in love with each other is what we have still to explain. All the rigid systems of brother and sister avoidance exist, it would seem, to prevent what never would have occurred, had the young people been allowed to grow up together. For in that case they could have had (we are to fancy) no erotic desires towards each other; that is Dr. Westermarck's idea. But could they not? He tells us that, among the Annamese, 'no girl who is twelve years old and has a brother is a virgin' (p. 292). And the Hottentots do not 'marry out of their own kraals' (p. 347).
Then where are we, exactly? If there is 'a real powerful instinct' against love between persons who 'have lived in a long-continued intimate relationship' from childhood—why does the instinct fail to affect Annamese and Hottentots, for instance? And if to be absolute strangers to each other is apt to make two young people fall in love, why do New-Caledonian brothers and sisters never do it? (Compare Mr. Crawley, The Mystic Rose, pp. 444-446.)
[1] How do we know that homo was still alalus?—A. L.
[2] Later, as we further analyse the chords in the great hymn of human existence, we shall find that this first of all rules of intelligent moral action, however little it may have had of ethical intention in its inception, will ever remain (in its effects) the fundamental note in the harmony of psychical life. All succeeding law is its inevitable corollary, and vibrating in cadence with this fundamental note.