The history of evolution alone solves the riddle of the origin of the organs of sexual congress, and renders their purpose clear to us. In a most ingenious manner, W. Bölsche distinguishes three problems in this history of the genital organs: the “aperture-problem,” the “member-problem,” and the “libido-problem.”
The first problem relates to the character and the position of the two apertures from which the sexual products, the reproductive cells, issue; the second relates to the exact mutual adaptation of the male and the female reproductive apertures; the third relates to the impulse to the intimate apposition of the genital apertures in consequence of a powerful nervous stimulus.
The most remarkable fact that we encounter in our consideration of the first problem—the “aperture-problem”—is the intimate association between the sexual aperture and the excretory canal of the urinary apparatus both in woman and in man—in the latter, indeed, the association is more pronounced. There seems to be a sort of parsimony on the part of Nature to combine so closely these two excretory tubes of the urine and of the products of sexual activity. Phylogenetically, indeed, the reproductive products originally passed with the urine freely into the open, and it was there that their conjugation took place. Among certain worms still existing at the present day we find this “urine-love.” Later, the genital canal became separated from the urinary canal, but the two tubes remained partly united at their outlets, opening side by side at the same part of the body. In man, indeed, the urethra still subserves the double purpose of the excretion of urine and the emission of semen. In woman the two excretory apertures are distinct, but they open in close proximity into the genital fissure between the thighs.
The intimate connexion which thus obtains between the urinary and the reproductive organs is not without significance for the understanding of certain aberrations of the libido sexualis. The same is true of the relations between the orifice of the genital passage and the similarly adjacent aperture of the large intestine, the anus. “Anus,” or, better, “cloaca love,” plays a part, indeed, in many fishes, amphibia, and reptiles; in these the act of procreation and the excretion of urine and fæces all take place by way of the cloaca. Among the mammals, at an early stage of phylogenetic development the intestine became completely separated from the sexual rudiment and the sexual excretory passages; and it is only in the proximity of the respective orifices that we find an indication of the primitive association. The act of pæderasty reminds us of the same fact.
The “aperture-problem” itself leads us, in the course of progressive development, to the “member-problem”—that is to say, to the problem of the more accurate apposition of the two reproductive apertures. The penis, by its introduction into the body of a member of the opposite sex, acts as a means for the shortening of distance-love; it serves for the fixation, for the clamping together, of the copulating pair, which in earlier stages of animal life was effected by sucking and biting; for example, in birds, who for the most part lack an actual penis, the cock holds the hen firmly with his beak during intercourse, and the sucking and biting which often occur in human beings in the sexual act persist as a reminiscence of these relations. In various vertebrates other means of fixation are employed: by the shape of fins, of arms, or of legs, a close “embrace” is rendered possible; finally, the evolution of a special member for sexual purposes closed the long series of means of ensuring union. Originally no more than a peg or a spine, in man the penis is first developed into the form of an absolutely free limb. Dogs, beasts of prey, rodents, bats, and apes, have a strong bone in the organ, the so-called “penis-bone.” In man this bone is lacking; the penis has become entirely free. W. Bölsche writes:
“In relation to the large, heavy, massive trunk and thighs, the sharply individualized, independent, mobile penis appears as a kind of spiritualized central point; as it were, a finger or a small third hand to the trunk, appearing to the eye to stand in rhythmical relation with the hands, right and left.”
In phylogenetic parallelism with the development of the penis, proceeds (from the marsupials upwards) the descensus testiculorum, the descent of the male reproductive glands, the testicles, until they attain their final position in the scrotum, beneath the penis. Here also we can recognize the principle of “limb-mobility,” mentally refined mobility.
In the clitoris woman also possesses a rudiment of a primitive penis. By the apposition of the two limbs, a more complete and rapid conjunction of the reciprocal sexual products must have been effected. But the further development of the large sexual aperture of the female checked the progressive development of this primitive penis, made it to some extent superfluous, since now, by the adaptation of the male penis to the female sexual aperture, a sufficient internal fixation in the act of copulation was rendered possible. Thus the female penis came to subserve other purposes: a portion of it formed the labia minora; another portion, the upper, the clitoris, the name of which sufficiently indicates the fact that, like the penis of the male, its function is connected with the voluptuous sense.
This leads us to the third and last problem, the “libido-problem.” In the human species voluptuous pleasure is almost completely divorced from the process of “fusion-love,” the coalescence of spermatozoon and ovum, and has for the most part become a phenomenon of “distance-love.” It appears extremely doubtful if there is anything specific about the voluptuous sensation—whether there is, in fact, a special “sexual sense.” Magnus Hirschfeld assumes the existence of peculiar “sexual cells,” of receptive areas for sexual stimuli, furnished with a sensory substance endowed with a peculiar specific sensibility. He regards love and the sexual impulse as “a molecular movement or force of a quite specific quality, streaming through the nervous system,” and accompanied by a quite peculiar sensation, or pleasure-tone, arising from a condition of excitement of the sexual cells. But, as we have already pointed out, the voluptuous sensation is merely a special case of general cutaneous sensibility; it is very closely allied with the cutaneous sensation of tickling; properly speaking, it is no more than an excessively powerful tickling.[14] It has also intimate relations with the sensation of pain.[15] The structure and position of the nerve-terminal apparatus of the genital organs, by means of which voluptuous pleasure is rendered possible, exhibit great similarity with the touch corpuscles and sensory end-organs of other parts of the skin. In the sexual orgasm the general cutaneous sensation increases to so high a degree of intensity, becomes so powerful, that for an instant consciousness is actually lost. The association of a momentary loss of consciousness with the acme of sensation indicates the summit of sexual pleasure—it is an abandonment, a dissolution, of individual personality.
Voluptuous pleasure plays its part in the human species entirely in the sphere of distance-love. Bölsche has very beautifully described its significance in this relation: