An important clue in this connection has recently been given to us in the view expressed by a philologist (H. Sperber, of Upsala, who works independently of psycho-analysis), that sexual needs have had the largest share in the origin and development of language. He says that the first sounds uttered were a means of communication, and of summoning the sexual partner, and that in the later development the elements of speech were used as an accompaniment to the different kinds of work carried on by primitive man. This work was performed by associated efforts, to the sound of rhythmically repeated utterances, the effect of which was to transfer a sexual interest to the work. Primitive man thus made his work agreeable, so to speak, by treating it as the equivalent of and substitute for sexual activities. The word uttered during the communal work had therefore two meanings, the one referring to the sexual act, the other to the labour which had come to be equivalent to it. In time the word was dissociated from its sexual significance and its application confined to the work. Generations later the same thing happened to a new word with a sexual signification, which was then applied to a new form of work. In this way a number of root-words arose which were all of sexual origin but had all lost their sexual meaning. If the statement here outlined be correct, a possibility at least of understanding dream-symbolism opens out before us. We should comprehend why it is that in dreams, which retain something of these primitive conditions, there is such an extraordinarily large number of sexual symbols; and why weapons and tools in general stand for the male, and materials and things worked on for the female. The symbolic relation would then be the survival of the old identity in words; things which once had the same name as the genitalia could now appear in dreams as symbolizing them.