Our study thus far has made it clear that there are mystic dangers to be guarded against from human as well as extra-human sources. There is weakness to be feared as well as power, as shown by the food and sex taboos. And once again there is mystery in the different, the unusual, the unlike, that causes avoidance and creates taboos. Man's dislike of change from the old well-trodden way, no matter how irrational, accounts for the persistence of many ancient folkways[6] whose origins are lost in mystery.[A] Many of these old and persistent avoidances have been expanded in the development of social relationships until we agree with Mr. Crawley that taboo shows that "man seems to feel that he is treading in slippery places." Might it not be within the range of possibility that in the study of taboo we are groping with man through the first blind processes of social control?[B] [Footnote A: Prof. Franz Boas explains this tendency: "The more frequently an action is repeated, the more firmly it will become established ... so that customary actions which are of frequent repetition become entirely unconscious. Hand in hand with this decrease of consciousness goes an increase in the emotional value of the omission of these activities, and still more of the performance of acts contrary to custom."[7]] [Footnote B: No study of the tabu-mana theory, however delimited its field, can disregard the studies of religion and magic made by the contributors to L'Année Sociologique, notably MM. Durkheim and Levy-Bruhl, and in England by such writers as Sir Gilbert Murray, Miss Harrison, Mr A.B. Cook, Mr F.M. Cornford, and others. In their studies of "collective representations" these writers give us an account of the development of the social obligation back of religion, law, and social institutions. They posit the sacred as forbidden and carry origins back to a pre-logical stage, giving as the origin of the collective emotion that started the representations to working the re-enforcement of power or emotion resulting from gregarious living. This study is concerned, however, with a "social" rather than a "religious" taboo,--if such a distinction can somewhat tentatively be made, with the admission that the social scruple very easily takes on a religious colouring.]