If the nations haven’t the sense to be able (if they wish) to limit their families—short of resorting to such methods as War, Cannibalism, the spread of Disease, the exposure of Infants, and the like—one can only conclude that they must go on fighting and preying upon each other (industrially and militarily) till they gain the sense. Mere unbridled and irrational lust may have led to wars of extermination in the past. Love and the sacrament of a true and intimate union may come some day with the era of peace.
 Militating also against the idea of over-population is the fact that so much of our agricultural land is obviously uncared for and neglected.
THE FRIENDLY AND THE FIGHTING INSTINCTS
Fighting is certainly a deeply ingrained instinct in the human race—the masculine portion. In the long history of human development it has undoubtedly played an important part. It has even (such is the cussedness and contrariety of Nature) helped greatly in the evolution of love and social solidarity. There is no greater bond in early stages between the members of a group or tribe than the consciousness that they have a common enemy. It is also obviously still a great pleasure to a very large proportion of our male populations—as, indeed, the fact of its being the fulfilment of a deep instinct would lead us to expect. It does not follow, however, from these remarks that we expect war in its crudest form to continue for ever. There will come a term to this phase of evolution. Probably the impact and collision between nations—if required for their impregnation and fecundity—will come about in some other way.
If fighting is an ingrained instinct, the sociable or friendly instinct is equally ingrained. We may, indeed, suppose it roots deeper. In the midst of warfare maddest foes will turn and embrace each other. In the tale of Cuchulain of Muirthemne he (Cuchulain) and Ferdiad fought for three days on end, yet at the close of each day kissed each other affectionately; and in the present war there are hundreds of stories already in circulation of acts of grace and tenderness between enemies, as well as the quaintest quips and jokes and demonstrations of sociability between men in opposing trenches who “ought” to have been slaying each other. In the Russo-Japanese War during the winter, when military movement was not easy, and the enemy lines in some cases were very near each other, the men, Russians and Japanese, played games together as a convenient and pleasant way of passing the time, and not unfrequently took to snowballing each other.