the continuation of the sexual process.  Besides the pleasure of gratification a certain amount of sexual tension appears even in infancy, though it is less constant and less abundant.  We can now understand also why in the discussion of the sources of sexuality we had a perfectly good reason for saying that the process in question acts as sexual gratification as well as sexual excitement.  We note that on our way towards the truth we have at first enormously exaggerated the distinctions between the infantile and the mature sexual life, and we therefore supplement what has been said with a correction.  The infantile manifestations of sexuality determine not only the deviations from the normal sexual life but also the normal formations of the same.

THE PROBLEM OF SEXUAL EXCITEMENT

It remains entirely unexplained whence the sexual tension comes which originates simultaneously with the gratification of erogenous zones and what is its nature.  The obvious supposition that this tension originates in some way from the pleasure itself is not only improbable in itself but untenable, inasmuch as during the greatest pleasure which is connected with the voiding of sexual substance there is no production of tension but rather a removal of all tension.  Hence, pleasure and sexual tension can be only indirectly connected.

The Role of the Sexual Substance.—­Aside from the fact that only the discharge of the sexual substance can normally put an end to the sexual excitement, there are other essential facts which bring the sexual tension into relation with the sexual products.  In a life of continence the sexual activity is wont to discharge the sexual substance at night during pleasurable dream hallucinations of a sexual act, this discharge coming at changing but not at entirely capricious intervals; and the following interpretation of this process—­the nocturnal pollution—­can hardly be rejected, viz., that the sexual tension which brings about a substitute for the sexual act by the short hallucinatory road is a function of the accumulated semen in the reservoirs for the sexual products.  Experiences with the exhaustibility of the sexual mechanism speak for the same thing.  Where there is no stock of semen it is not only impossible to accomplish the sexual act, but there is also a lack of excitability in the erogenous zones, the suitable excitation of which can evoke no pleasure.  We thus discover incidentally that a certain amount of sexual tension is itself necessary for the excitability of the erogenous zones.