In all these promptings of instinct, in all these categorical imperatives of the nerves and the blood, human beings must be at the same time obedient listeners and strict masters. On this depends the future happiness of love, and with it a happier future race. The people of to-day live under inherited morals and newly acquired transgressions of morality. Both must be conquered before soul and sense in love can become inseparable, or in other words, before this unity is recognised as the only possible moral basis of the relation between man and woman. Talented men, as well as one-sided advocates of women's rights, think that the development will take quite a different course, after the low impulse which is at the basis of love has been laid bare and scientifically analysed. They say that the superior person will satisfy the impulse shamelessly and animally, without any emotional decoration; or he will isolate himself from its influence and devote to more noble purposes that vital power, that emotional capacity, which is now consumed by love. Nothing impossible is to be found in this point of view. I have shown more than once that woman by her maternal functions, uses up so much physical and psychical energy, that in the sphere of intellectual production she must remain of less significance. What I at an earlier period assumed intuitively, has been substantiated since then by a specialist. A Finnish doctor has shown how the vital power of lower organisms, is concentrated in sexual production. But the higher man goes, so much more power is made free. This power which is not consumed in the production of new generations, can serve intellectual production. Each of the two different productive expressions of human vital action must to a certain extent limit the development of the power of the other, and restrict its capacity of work. The same writer contends that this is the natural cause of the more limited fertility of civilised man, and will be, according to the pessimists named above, the decisive factor in the prophesied downfall of love.