This remains true even though the doctrine of _Lombroso_ and _Tarnowsky_ should find fuller justification, the doctrine that the practice of prostitution by women is the natural expression of a congenital morbid predisposition, “which impels them, in defiance of their direct advantage, of reason, and of all counter-advice, to adopt this accursed mode of life.” Prostitution, in this view, is to be regarded as the inevitable outcome of congenital moral insanity. This is certainly true of a small proportion of prostitutes, but is as certainly false of the great majority, in whom unfavorable, difficult conditions of life form the determining cause. A certain inherited or acquired mental disposition may, indeed, be assumed to exist in these cases also—an unstable moral equilibrium, an insufficient development of the force of the will and of the power of resistance. The hygienic requirement of married life for woman during the menacme is undoubtedly sometimes hard to fulfil in our day, when the more elaborate and expensive standard of life has increased the difficulty of supporting a family; but from the medical point of view it is necessary to insist forcibly on this categorical imperative, in opposition to the view advanced by the modern women’s rights’ party, that “love is moral also in the absence of legal marriage” (_Ellen Key_); in opposition to the yet more extreme opinion of _George Sand_ and of _Almquist_, who, regardless of consequences, declare marriage to be immoral; and, finally, in opposition to the advocates of “free love,” who wish woman to be as free as man in sexual relations. Much as we may wish that man and wife should be in complete harmony in marriage, and that they should feel themselves to be firmly united alike by mutual love and by a reciprocal sense of duty, none the less we must consider the modern maiden ripe for marriage as unjustified in demanding, before undertaking marriage, “perfect love as typifying the inner yearning of two beings to become one;” and we must regard the latter-day woman as extravagant in insisting that the man shall enter upon marriage in a condition as virgin as that of his contemplated wife. “Perfect love” is as rare and as little to be expected as perfect beauty; and the sexual life of man differs entirely in nature and in the course of its development from the sexual activity of women.