Mantegazza very finely describes, in his "Physiology of Love," the longings, impulses, fears, of the awakening sexual life, existing long before that life is capable of manifesting itself in the precreative act; tracing their influence on the mind and emotions, and giving their subtle impetus to the trend of human feeling, in such a way as to show that, whatever our definition of it may be, sexuality not only begets humanity but shapes its destiny; and showing that in the religious, as well as the sexual life, love is transcendental.

In neither realm can it be reduced to any rule of empirical knowledge. It becomes, therefore, in all its mental processes, wholly a creature of the imagination; and as the intensification of one element of life naturally intensifies those other elements with which it is associated, it may be readily seen how the extreme development of the ethical may affect the sexual idea, in the quest of that immortal object which is the ultimate purpose of both. Only in one point do they differ. In sexual love, the true purpoee of its creation—the propagative one—is lost sight of in the consciousness of the act, the strength of desire being God's all-sufficient safeguard for the fulfilment of a duty which is paramount in creation, and which otherwise might be overcome by the multiplicity of opposing motives. In religion, the reverse is the case.