*Fore-pleasure Mechanism.*--But the rôle which devolves upon the erogenous zones is clear. What applies to one applies to all. They are all utilized to furnish a certain amount of pleasure through their own proper excitation, which increases the tension, and which is in turn destined to produce the necessary motor energy in order to bring to a conclusion the sexual act. The last part but one of this act is again a suitable excitation of an erogenous zone; _i.e._, the genital zone proper of the glans penis is excited by the object most fit for it, the mucous membrane of the vagina, and through the pleasure furnished by this excitation it now produces reflexly the motor energy which conveys to the surface the sexual substance. This last pleasure is highest in its intensity, and differs from the earliest ones in its mechanism. It is altogether produced through discharge, it is altogether gratification pleasure and the tension of the libido temporarily dies away with it.
It does not seem to me unjustified to fix by name the distinction in the nature of these pleasures, the one through the excitation of the erogenous zones, and the other through the discharge of the sexual substance. In contradistinction to the end-pleasure, or pleasure of gratification of sexual activity, we can properly designate the first as _fore-pleasure_. The fore-pleasure is then the same as that furnished by the infantile sexual impulse, though on a reduced scale; while the _end-pleasure_ is new and is probably connected with determinations which first appear at puberty. The formula for the new function of the erogenous zones reads as follows: they are utilized for the purpose of making possible the production of the greater pleasure of gratification by means of the fore-pleasure which is gained from them as in infantile life.
I have recently been able to elucidate another example from a quite different realm of the psychic life, in which likewise a greater feeling of pleasure is achieved by means of a lesser feeling of pleasure which thereby acts as an alluring premium. We had there also the opportunity of entering more deeply into the nature of pleasure.[2]
*Dangers of the Fore-pleasure.*--However the connection of fore-pleasure with the infantile life is strengthened by the pathogenic rôle which may devolve upon it. In the mechanism through which the fore-pleasure is expressed there exists an obvious danger to the attainment of the normal sexual aim. This occurs if it happens that there is too much fore-pleasure and too little tension in any part of the preparatory sexual process. The motive power for the further continuation of the sexual process then escapes, the whole road becomes shortened, and the preparatory action in question takes the place of the normal sexual aim. Experience shows that such a hurtful condition is determined by the fact that the erogenous zone concerned or the corresponding partial impulse has already contributed an unusual amount of pleasure in infantile life. If other factors favoring fixation are added a compulsion readily results for the later life which prevents the fore-pleasure from arranging itself into a new combination. Indeed, the mechanism of many perversions is of such a nature; they merely represent a lingering at a preparatory act of the sexual process.