When we come to "General Moral Causes," heredity plays the first part. This may be direct, i.e., the son of a genesiac will have the same tastes as his father, or transformed; what is phthisis in one generation assuming the form of sexual aberration in another. Bad education and exposure to bad examples, together with imitation, are insisted on more vaguely. The "Individual Moral Causes" include impressions received in early youth, on which I think perhaps Moreau does not lay sufficient stress, and certain tendencies to subjective preoccupations with ideal ideas, certain abnormal physical conditions which disturb the whole moral sensibility. Passing to Pathological Anatomy, Moreau declares that it is as yet impossible to localise the sexual sense. The brain, the cerebellum, the spinal marrow? We do not know. He seems to incline toward the cerebellum. It is not necessary to follow Moreau in his otherwise interesting account of the various manifestations of sexual disease. The greater part of these have no relation to the subject of my work. But what he says in passing about "pæderasts, sodomites, saphists," has to be resumed. He reckons them among "A class of individuals who cannot and ought not to be confounded either with men enjoying the fulness of their intellectual faculties, or yet with madmen properly so called. They form an intermediate class, a mixed class, constituting a real link of union between reason and madness, the nature and existence of which can most frequently be explained only by one word: Heredity" (p. 159). It is surprising, after this announcement, to discover that what he has to say about sexual inversion is limited to Europe and its moral system, "having nothing to do with the morals of other countries where pæderasty is accepted and admitted" (p. 172, note). Literally, then, he regards sexual inversion in modern Christian Europe as a form of hereditary neuropathy, a link between reason and madness; but in ancient Greece, in modern Persia and Turkey, he regards the same psychological anomaly from the point of view, not of disease, but of custom. In other words, an Englishman or a Frenchman who loves the male sex must be diagnosed as tainted with disease; while Sophocles, Pindar, Pheidias, Epaminondas, Plato, are credited with yielding to an instinct which was healthy in their times because society accepted it. The inefficiency of this distinction in a treatise of analytical science ought to be indicated. The bare fact that ancient Greece tolerated, and that modern Europe refuses to tolerate sexual inversion, can have nothing to do with the etiology, the pathology, the psychological definition of the phenomenon in its essence. What has to be faced is that a certain type of passion flourished under the light of day and bore good fruits for society in Hellas; that the same type of passion flourishes in the shade and is the source of misery and shame in Europe. The passion has not altered; but