_Moll_, to whom we owe the first great comprehensive work on homosexuality, is of an entirely different opinion. He states: “Considering the sexual instinct not as a means for the attainment of pleasure but as standing in the service of procreation we must look upon exclusive homosexuality as belonging to the realm of pathology.” (_Die kontraere Sexualempfindung_, Berlin, 1899, 3rd edn.) This is an untenable argument. _For there is no procreative instinct as such, only a sexual instinct._ Science is not concerned with the study of purposiveness, it is interested in the ascertainment of facts. Science must not and cannot be placed in the service of teleology. At any rate _Moll_ is inclined to look upon homosexuality as a neurosis: he claims to have found in recent years a growing tendency among investigators to establish a border province between mental health and disease, “and into that realm have been relegated many cases of psychic degeneration—I may mention, for instance, certain compulsory neuroses. I believe it is proper that we should place in the same category the contrary sexual feeling.” (_Loc. cit._ p. 435.) He refers here to _Westphal_ who compares homosexuality to moral insanity.[7] Notwithstanding _Moll’s_ opinion we must state that most modern investigators declare that they have examined many homosexuals whom they have found normal or have at least designated as normal. _Havelock Ellis_ and _Albert Moll_[8] very appropriately state in their last joint work: “_Naecke_ has repeatedly maintained that the homosexuals are perfectly healthy and aside from their specific deviation may be normal in every respect. We have always maintained this view although, contrary to _Naecke_, we assume that _homosexuality is very frequently found in intimate association with minor nervous states_. We agree with _Hirschfeld_ that heredity plays a rôle in no more than 25 per cent of the cases of homosexuality and that, although a neuropathic background may be present in homosexuality, the degenerative factor plays but a small role.” These authors find the hypothesis that every person’s constitution combines the male and female elements a keen concept though rather hypothetical. “But still it is undoubtedly justified, if we look upon homosexuality as an inborn anomaly or, to speak more correctly, as an anomaly resting on constitutional traits, which if morbid, are so only in _Virchow’s_ sense, according to whom pathology is not the science of diseases but of deviations, so that the homosexual may be as healthy as the color blind. Inborn homosexuality ranks on the level of a biologic variation: it is a variation, representing perhaps an incomplete phase of sexual differentiation, but bearing no discernible relationship to any morbid condition of the individual.”