The chief source of the history of the analytic conception of libido is Freud’s “Three Contributions to the Sexual Theory.” There the term libido is conceived by him in the original narrow sense of sexual impulse, sexual need. Experience forces us to the assumption of a capacity for displacement of the libido, because functions or localizations of non-sexual force are undoubtedly capable of taking up a certain amount of libidinous sexual impetus, a libidinous afflux.[238] Functions or objects could, therefore, obtain sexual value, which under normal circumstances really have nothing to do with sexuality.[239] From this fact results the Freudian comparison of the libido with a stream, which is divisible, which can be dammed up, which overflows into branches, and so on.[240] Freud’s original conception does not interpret “everything sexual,” although this has been asserted by critics, but recognizes the existence of certain forces, the nature of which are not well known; to which Freud, however, compelled by the notorious facts which are evident to any layman, grants the capacity to receive “affluxes of libido.” The hypothetical idea at the basis is the symbol of the “Triebbündel”[241] (bundle of impulses), wherein the sexual impulse figures as a partial impulse of the whole system, and its encroachment into the other realms of impulse is a fact of experience. The theory of Freud, branching off from this interpretation, according to which the motor forces of a neurotic system correspond precisely to their libidinous additions to other (non-sexual) functional impulses, has been sufficiently proven as correct, it seems to me, by the work of Freud and his school.[242] Since the appearance of the “Three Contributions,” in 1905, a change has taken place[243] in the libido conception; its field of application has been widened. An extremely clear example of this amplification is this present work. However, I must state that Freud, as well as myself, saw the need of widening the conception of libido. It was paranoia, so closely related to dementia præcox, which seemed to compel Freud to enlarge the earlier limits of the conception. The passage in question, which I will quote here, word for word, reads:[244]