A condition in which the normal heterosexual impulse contains a trace of homosexuality, or the latter a portion of the former. In probably plainer terms, when, along with habitual desire for the same sex, desire for the opposite sex may occur, or when habitual desire for the opposite sex is associated with transient desire for the same sex, one desire being secondary to the other in degree, and the weaker manifesting itself only episodically, or under conditions of unusual sexual stimulation.

Thus, married men, who will be found, however, to have usually some pre-existing homosexual taint, will frequently sustain sexual relations with men;1 and married women with other women; although I doubt whether the occurrence of such phenomena, or the definiteness of the feeling involved, warrants the separation of the latter from the sphere of simple sexual inversion ; or bestowing upon it very different treatment, or consideration, than the latter calls for.

1 In more than one place in this work the reader will doubtless be struck with the fact that the author, while recounting the various views of others, refrains, for the most part, from expressing his own. This is intended to imply that further research is not only passible but necessary. When all arguments are exhausted, only, is the writer justified in formulating a conclusion; in all other cases, as Goethe wisely remarks, the inquirer being "simply one of a jury." All departments of human knowledge necessarily blend with one another, and in order to a complete view of any one, we must take more or less cognizanc" Of all the rest, I take it thai tin- main putpn*- uf :i work of this character is to review what has already been written on the subject, add whatever is possible of original knowledge, suggest probabilities, as well as the application of given principles, and then leave his work to the judgment of his readers; particularly where, as in this case, those readers are presumed to be careful students of the same subject.

Many cases of uxorial and marital coldness may, possibly, be thus accounted for; but it is always well to remember that, even to the pronounced homosexualist, intercourse with the opposite sex is rarely, if at all, wholly impossible; and also, that to many who have forsaken the homosexual, and adopted, permanently, the heterosexual role, traces of the older instinct will frequently appear; so that a differential diagnosis between simple inversion and psychosexual hermaphroditism, so long as any vestiges of normality survive in the abnormal, or any symptoms of abnormality, appear in the normal, is not only difficult, but impossible, from a standpoint of strict scientific accuracy.

A man may be a confirmed masturbator, and yet enjoy fairly healthy intercourse with a woman; another man, by the mere vigor of his vita sexualis, may be led into pederasty, or fellatio; while a third, though normally homosexual, may be drawn into heterosexual relationship by some aesthetic, or ethical, factor which he found lacking in the contrary case. Thus, everything considered, the line of demarcation seems so faintly drawn between the two conditions as not to justify, in my view at least, the separate treatment which Kraff t-Ebing, and other writers, have accounted them. I have seen fit, therefore, to include the phenomena of both, where I judge them properly to belong, among those of simple sexual inversion.