At this point we may recall the confusing information which Wundt offered us about the double meaning of the word taboo, namely, holy and unclean (see above). It was supposed that originally the word taboo did not yet mean holy and unclean but signified something demonic, something which may not be touched, thus emphasizing a characteristic common to both extremes of the later conception; this persistent common trait proves, however, that an original correspondence existed between what was holy and what was unclean, which only later became differentiated. In contrast to this, our discussion readily shows that the double meaning in question belonged to the word taboo from the very beginning and that it serves to designate a definite ambivalence as well as everything which has come into existence on the basis of this ambivalence. Taboo is itself an ambivalent word and by way of supplement we may add that the established meaning of this word might of itself have allowed us to guess what we have found as the result of extensive investigation, namely, that the taboo prohibition is to be explained as the result of an emotional ambivalence. A study of the oldest languages has taught us that at one time there were many such words which included their own contrasts so that they were in a certain sense ambivalent, though perhaps not exactly in the same sense as the word taboo[88]. Slight vocal modifications of this primitive word containing two opposite meanings later served to create a separate linguistic expression for the two opposites originally united in one word. The word taboo has had a different fate; with the diminished importance of the ambivalence which it connotes it has itself disappeared, or rather, the words analogous to it have vanished from the vocabulary. In a later connection I hope to be able to show that a tangible historic change is probably concealed behind the fate of this conception; that the word at first was associated with definite human relations which were characterized by great emotional ambivalence from which it expanded to other analogous relations. Unless we are mistaken, the understanding of taboo also throws light upon the nature and origin of _conscience_. Without stretching ideas we can speak of a taboo conscience and a taboo sense of guilt after the violation of a taboo. Taboo conscience is probably the oldest form in which we meet the phenomenon of conscience. For what is ‘conscience’? According to linguistic testimony it belongs to what we know most surely; in some languages its meaning is hardly to be distinguished from consciousness.