738 THE POPULAR SCIENCE MONTHLY. 



tion of rulers, to the reckless turbulence of the ruled, to the debasing 

 effects of wealth and luxury, and to the devastating wars which have 

 formed a great part of the occupation of mankind, as the causes of the 

 decay of states and the foundering of old civilizations, and thereby 

 point their story with a moral. No doubt immoral motives of all sorts 

 have figured largely among the minor causes of these events. But, 

 beneath all this superficial turmoil, lay the deep-seated impulse given 

 by unlimited multiplication. In the swarms of colonies thrown out 

 by Phoenicia and by old Greece ; in the " ver sacrum " of the Latin 

 races ; in the floods of Gauls and of Teutons which burst over the 

 frontiers of the old civilization of Europe ; in the swaying to and fro 

 of the vast Mongolian hordes in late times, the population problem 

 comes to the front in a very visible shape. Nor is it less plainly man- 

 ifest in the everlasting agrarian questions of ancient Rome than in the 

 Arreoi societies of the Polynesian Islands. 



In the ancient world and in a large part of that in which we now 

 live, the practice of infanticide was or is a regular and legal custom ; 

 the steady recurrence of famine, pestilence, and war were and are 

 normal factors in the struggle for existence, and have served, in a 

 gross and brutal fashion, to mitigate the intensity of its chief cause. 



But, in the more advanced civilizations, the progress of private 

 and public morality has steadily tended to remove all these checks. 

 We declare infanticide murder, and punish it as such ; we decree, not 

 quite successfully, that no one shall die of hunger ; we regard death 

 from preventable causes of other kinds as a sort of constructive mur- 

 der, and eliminate pestilence to the best of our ability ; we declaim 

 against the curse of war and the wickedness of the military spirit, 

 and we are never weary of dilating on the blessedness of peace and the 

 innocent beneficence of industry. In their moments of expansion, 

 even statesmen and men of business go thus far. The finer spirits 

 look to an ideal "civitas Dei"; a state when, every man having 

 reached the point of absolute self-negation, and having nothing but 

 moral perfection to strive after, peace will truly reign, not merely 

 among nations, but among men, and the struggle for existence will be 

 at an end. 



Whether human nature is competent, under any circumstances, to 

 reach, or even seriously advance toward, this ideal condition, is a 

 question which need not be discussed. It will be admitted that man- 

 kind has not yet reached this stage by a very long way, and ray 

 business is with the present. And that which I Avish to point out is 

 that, so long as the natural man increases and multiplies without re- 

 straint, so long will peace and industry not only permit, but they will 

 necessitate, a struggle for existence as sharp as any that ever went on 

 under the regime of war. If Istar is to reign on the one hand, she 

 will demand her human sacrifices on the other. 



Let us look at homo. For seventy years, peace and industry have 



