We thus find two opinions widely current: one, of world-wide existence and almost universally accepted in those ages and centers in which life is lived most nakedly, according to which the sexual impulse is stronger in women than in men; another, now widely prevalent in many countries, according to which the sexual instinct is distinctly weaker in women, if, indeed, it may not be regarded as normally absent altogether. A third view is possible: it may be held that there is no difference at all. This view, formerly not very widely held, is that of the French physiologist, Beaunis, as it is of Winckel; while Rohleder, who formerly held that sexual feeling tends to be defective in women, now believes that men and women are equal in sexual impulse. At an earlier period, however, Donatus (_De Medica Historia Mirabili_, 1613, lib. iv, cap. xvii) held the same view, and remarked that sometimes men and sometimes women are the more salacious, varying with the individual. Roubaud (_De l'Impuissance_, 1855, p. 38) stated that the question is so difficult as to be insoluble. In dealing with the characteristics of the sexual impulse in women, it will be seen, we have to consider the prevalence in them of what is commonly termed (in its slightest forms) frigidity or hyphedonia, and (in more complete form) sexual anesthesia or anaphrodism, or erotic blindness, or anhedonia.[157] Many modern writers have referred to the prevalence of frigidity among women. Shufeldt believes (_Pacific Medical Journal_, Nov., 1907) that 75 per cent, of married women in New York are afflicted with sexual frigidity, and that it is on the increase; it is rare, however, he adds, among Jewish women. Hegar gives 50 per cent, as the proportion of sexually anesthetic women; Fürbringer says the majority of women are so. Effertz (quoted by Löwenfeld, _Sexualleben und Nervenleiden_, p. 11, apparently with approval) regards 10 per cent, among women generally as sexually anesthetic, but only 1 per cent, men. Moll states (Eulenburg's _Encyclopädie_, fourth edition, art. "Geschlechtstrieb") that the prevalence of sexual anesthesia among German women varies, according to different authorities, from 10 to 66 per cent. Elsewhere Moll (_Konträre Sexualempfindung_, third edition, 1890, p. 510) emphasizes the statement that "sexual anesthesia in women is much more frequent than is generally supposed." He explains that he is referring to the physical element of pleasure and satisfaction in intercourse, and of desire for intercourse. He adds that the psychic side of love is often more conspicuous in women than in men. He cannot agree with Sollier that this kind of sexual frigidity is a symptom of hysteria. Féré (_L'Instinct Sexuel_, second edition, p. 112), in referring to the greater frequency of sexual anesthesia in women, remarks that it is often