To disengage from his learned book, _The Mystic Rose_ (1902), Mr. Crawley’s theory of the origin of exogamy is no easy task. He strongly insists on the ‘religious’ element in all early human thought, and as in ‘religion’ he includes the vague fears, misgivings, and ideas of ‘luck,’ which haunt even the least religious of modern men, we may say that ‘religion,’ in this sense, mingles with the thought of all ages. The present writer, like Dr. Johnson, is an example of the ‘religious’ character, and of Mr. Crawley’s remark that ‘human nature remains potentially primitive.’ To the ‘religious’ man or woman (using ‘religious’ in this sense) the universe is indeed a thing of delicate poise, and may ‘break, and bring down death,’ if we walk under a ladder, or spill the salt, or enter a doorway with the wrong foot foremost, or fail to salute a magpie, or the new moon. The superstitious anthropologist, of course, knows that all these apprehensions of his are utterly absurd, but the savage is careful and troubled about them. The Philistine, on the other hand, is proud of his conquest of these airy terrors: he ‘cannot imagine what people mean by such nonsense,’ and, exactly so far as he is sincere, he cannot comprehend early mankind. Now, as to exogamy, our difficulty is to understand why breach of the rule against certain marriages is, everywhere, so deadly a sin: so black an offence against ‘religion.’ Mr. Crawley’s explanation is not, perhaps, easily to be disengaged from the mass of his work, but it begins in his appreciation of the δεισιδαιμονία of early men, their ever-present sense of ‘religious’ terrors. ‘Thus all persons are potentially dangerous to others, as well as potentially in danger....’[40] This sense of peril arises ‘in virtue simply of the distinction between a man and his fellows.’ Much more, then, are women dangerous to men, and men to women, the sexes being so distinct from each other. We know that the most extraordinary precautions are taken to avoid contact with women in certain circumstances, and a well-known story of Sir John Mandeville’s is only one case of the fact that the bridegrooms of some races, from a superstitious terror, insist on being made _cocus en herbe_. Messrs. Spencer and Gillen give the instance of ‘the marriage ceremony’ (an odious brutality) among the Arunta of Central Australia.[41] It is perhaps intended to deliver the bridegroom from a peril imagined by superstition (as in Mandeville’s tale);[42] and, without it, the Australian would resemble the man derided in the old Scottish song: The Bridegroom grat when the sun gaed doon.