Mr. Pycraft, in his book on this subject,[5] remarks that the tremendous power of "mate-hunger" has been overlooked by a strange confusion of cause and effect. Almost universally its sequel, the production of offspring, has been regarded as the dominant instinct in the higher animals, but this view has no foundation in fact. Desire, for the sake of the pleasure which its gratification affords, and not its consequences, is the only hold on life which any race possesses. And this is true both in the case of man himself and of the beasts that perish. Those whose business it is, for one reason or another, to study these emotions, know well that "mate-hunger" may be as ravenous as food-hunger, and that, with some exceptions, it is immensely more insistent in the males than in the females. But for this appetite, reproduction in many species could not take place, for the sexes often live far apart, and mates are only to be won after desperate conflict with powerful rivals no less inflamed. It is idle to speak of an equality between the sexes in this matter, either in regard to animals or in the human race. The male is dominated by the desire to gratify the sexual appetite; in the female this is modified by the stimulation of other instincts concerned with the care of offspring. Amorousness is the underlying factor which has shaped and is sustaining human society, and is no less powerful among the lower animals. Much that is considered contrary to human nature, and either outrageous or ridiculous, would be understood and wisely dealt with if knowledge of nature, including man's nature, were cultivated, and took the place of vain assertions as to "what should be," accompanied by ignorance of "what is." [5] "The Courtship of Animals," Hutchinson, 1913.