Husbands who would consider this average as an imprescriptible right would, however, make wrong pretensions, for it is quite possible for a normal man to contain himself much longer, and it is his duty to do so, not only when his wife is ill, but also during menstruation and pregnancy.

The question of sexual relations during pregnancy is more difficult, on account of its long duration. In this case caution is necessary, but total abstinence from sexual connection is, in my opinion, superfluous.

The Desire of Change in Man.—A peculiarity of the sexual appetite in man, which is fatal for society, is his desire for change. This desire is not only one of the principal causes of polygamy, but also of prostitution and other analogous organizations. It arises from the want of sexual attraction in what one is accustomed to and from the stronger excitation produced by all that is new; a phenomenon of which we have spoken above. On the average, woman has a hereditary disposition which is much more monogamous than man. The sexual appetite thus loses its intensity from the prolonged habit of connection with the same woman, but, becomes much more intense with other women, if not in all men at any rate in most. Such desires may generally be overcome by the aid of a true and noble love, and by sentiments of duty and fidelity toward the family and toward a respected wife. We cannot, however, deny that they exist, nor that they are the cause of the worst excesses, and the most violent scenes, often with a tragic result. We shall return to this subject later.

Excitation and Cooling of the Sexual Appetite.—Without touching the domain of pathology, I must again dwell on the great individual diversity of the objects of the male sexual appetite. It is usually young but mature female forms of healthy appearance, and especially the sight of the nudity of certain parts of the body which are usually covered, particularly the breasts and sexual organs, which most strongly excite the sexual appetite in man. It is the same with the corresponding odors. The voice, the physionomy, the clothing and many other details may also provoke his desires. There are, however, men who are more excited by thin and pale women.

Certain attributes excite one and not another; for instance, the hair, certain odors, certain forms of face, a certain fashion of clothing, the form of the breasts, etc. The peculiarities, which are absent in women with whom a man has been on familiar terms in his youth are generally those which attract the most. In sexual matters contrasts tend to mutual attraction. Thin people often become enamored of fat, short ones of long ones, and inversely. One cannot, however, fix any rules. One often sees young men excited at the sight of women of older age, and old men enamored of very young women, even of children. All these discrepancies constitute the more important points of origin of sexual pathology. In spite of all, there still exist a great number of tranquil men with monogamous instincts and not fond of change. Lastly, we must not forget that super-abundant feeding and idleness exalt the sexual appetite and tend to polygamy, while hard work, especially physical, and frugal diet diminish it.

It is needless to say that the mental qualities react powerfully on the sexual appetite. A quarrelsome temper, coldness and repulsion on the part of a woman cool the desires of the man, while an ardent sexual desire on the part of the woman, her love and tenderness, tend to increase and maintain them. We are dealing here with purely animal sexual instinct, and we may state that the sexual appetite of woman generally excites strongly that of man, and considerably increases his pleasure during coitus. There are, however, exceptions in the inverse sense, in which coldness and disgust on the part of the woman excite the passion of certain men, who have, however, no taste for libidinous women. All degrees are found in this domain.

Active in the sexual act the man desires corresponding sentiments in the woman. But, on the other hand, all want of natural reserve, and delicate sentiment, and all cynical sexual provocation on the part of a woman, produce in the normal man a repulsive effect. The normal woman possesses an admirable instinct in these matters and knows how to betray her feelings in a sufficiently fine and delicate manner, so as not to hurt those of the man.

A phenomenon, which we shall meet with in Chapter VIII, under the name of psychic impotence, shows the powerful and disturbing interference of thoughts on the automatic action of instinctive sexual activity. A momentary psychic impotence is not necessarily pathological. While voluptuous sensations alternate during coitus with desire and corresponding erotic representations, a sudden idea of the ridiculousness of the situation, signs of pain or of bad temper in the woman, the idea of impotence or of the real object of coitus; finally, anything which acts as a contrast to the sensations and impulses of coitus, may interrupt it, so that the voluptuous sensations and sexual appetite disappear and erection subsides. Voluntary efforts are often incapable of putting things right again. The charm is broken, and only new images and new sentiments associated instinctively with the sexual appetite can be reëstablished, by making the subconscious state preponderate over the reasoning consciousness.

Influence of Modern Civilization. Pornography.—Human sexuality has been unfortunately perverted and in part grossly altered by civilization, which has even developed it artificially in a pathological sense. The point has been reached of considering as normal, relations which are in reality absolutely abnormal. For example, it is maintained that prostitution produces normal coitus in man. How can this term be seriously employed in speaking of connection with a prostitute who is absolutely indifferent to it, and who seeks only to excite her clients artificially and to get their money, without mentioning venereal diseases which she so often presents them with! Forgetful of the natural aim of the sexual appetite, civilization has transformed it into artificial enjoyment, and has invented all possible means to increase and diversify it.

As far back as the history of civilization goes we see this state of affairs, and in this sense we are neither better nor worse than our ancestors. But we possess more diverse and more refined measures than barbarian peoples, and than our direct ancestors, to satisfy our unwholesome desires. Modern art in particular often serves to excite eroticism, and we must frankly admit that it often descends to the level of pornography. Hypocritical indignation against those who dare to say this often serves only to cover in the name of art the most indecent excitants of eroticism.