To adduce more historical evidence of modern love would serve no purpose; in the next chapter I shall discuss its metaphysical consummation, the love-death.  But I will briefly point out the not quite obvious difference between synthetic love and sexuality projected on a specific individual.  In several of the higher animals the sexual instinct is to some extent individualised, but nevertheless it is no more than instinct, seeking a suitable mate for its gratification.  All the well-known theories of “sexual attraction,” from Schopenhauer to Weininger, accounting love as nothing but a mutual supplementing of two individuals for the purpose of the best possible reproduction of the species, do not apply to love in the modern sense, but to the sexual impulse; they completely disregard the individual, and are only aware of the species; they apprehend individualisation as an instrument in the service of the race.  But genuine personal love is not kindled by instinct; it is not differentiated sexual impulse; it embraces the psycho-physical unity of the beloved without being conscious of sexual desire.  It shares with the purely spiritual love the eagerness of man to raise and glorify the beloved woman, without ulterior motive or desire.  This distinction may be called hair-splitting, and I admit that it is frequently impossible to make it in practice, but it is important in principle because it goes back to origins and finds in the metaphysical climax of the third stage, the love-death, its practical anti-generic proof.  But with all this it is of common occurrence that spiritual and sensual love are at different times projected on one and the same woman.

Schopenhauer’s instinct of philoprogenitiveness has to-day become an article of faith with the learned and unlearned.  Schopenhauer was the first, probably, to conceive the idea that love was the consciousness of the unconscious instincts in the service of the species, and had no other content or purpose than the will of the species to produce the best possible offspring.  In a chapter of his principal work, entitled The Metaphysics of Love, he essayed to promulgate and prove his theory in detail.  “All love, however ethereal it may pretend to be, is rooted solely in the sexual instinct; it is nothing more nor less than specialised, strictly speaking individualised, sexual desire.”  Schopenhauer’s conception of love does not rise above this specialised impulse.  He calmly ignores all phenomena such as those I have described because they do not fit his theory.  With the exception of his cheap observation that contrasts attract each other (which is the pith of all his “truths”) he does not adduce the smallest evidence for the truth of his myth of “the genius of the species spreading his wings over the coming generation.”  However much the results of breeders may be applicable to the human species, they have nothing to do with love, and the believers in the theory of the instinct of philoprogenitiveness