Recent authorities are almost unanimous in rejecting masturbation as a cause of insanity. Thus, Rohleder, in his comprehensive monograph (_Die Masturbation_, 1899, pp. 185-92), although taking a very serious view of the evil results of masturbation, points out the unanimity which is now tending to prevail on this point, and lays it down that "masturbation is never the direct cause of insanity." Sexual excesses of any kind, he adds (following Curschmann), can, at the most, merely give an impetus to a latent form of insanity. On the whole, he concludes, the best authorities are unanimous in agreeing that masturbation may certainly injure mental capacity, by weakening memory and depressing intellectual energy; that, further, in hereditarily neurotic subjects, it may produce slight psychoses like _folie du doute_, hypochondria, hysteria; that, finally, under no circumstances can it produce severe psychoses like paranoia or general paralysis. "If it caused insanity, as often as some claim," as Kellogg remarks, "the whole race would long since have passed into masturbatic degeneracy of mind.... It is especially injurious in the very young, and in all who have weak nervous systems," but "the physical traits attributed to the habit are common to thousands of neurasthenic and neurotic individuals." (Kellogg, _A Text-book of Mental Diseases_, 1897, pp. 94-95.) Again, at the outset of the article on "Masturbation," in Tuke's _Dictionary of Psychological Medicine_, Yellowlees states that, on account of the mischief formerly done by reckless statements, it is necessary to state plainly that "unless the practice has been long and greatly indulged, no permanent evil effects may be observed to follow." Näcke, again, has declared ("Kritisches zum Kapitel der Sexualität," _Archiv für Psychiatrie_, 1899): "There are neither somatic nor psychic symptoms peculiar on onanism. Nor is there any specific onanistic psychosis. I am prepared to deny that onanism ever produces any psychoses in those who are not already predisposed." That such a view is now becoming widely prevalent is illustrated by the cautious and temperate discussion of masturbation in a recent work by a non-medical writer, Geoffrey Mortimer (_Chapters on Human Love_, pp. 199-205).