raised, and as democracy is perfected, so that each is given opportunity to do the work for which he is fit, the wealth and means of subsistence increase still more rapidly. The law of Malthus and the law of diminishing returns, like the law of the degradation of energy, may ultimately prevail, but not in any future with which we are concerned. The population of a civilized country, in which science is cultivated, need not be limited by famine, pestilence or war. Over-population and the need of expansion by conquest are obviated by democracy and science; the cause of war which may be regarded as inevitable and legitimate is thus abolished. In providing adequately for the subsistence of an increasing population, science has made a contribution to peace the magnitude of which can not be easily overstated.
Another great service for peace to be credited to science is the development of commerce, travel and intercommunication. Steam and electricity are handmaids of peace. Trade disputes and the misadventures of missionaries, travelers and immigrants may serve as causes or pretexts of wars, but the balance of commerce, travel and immigration is large on the side of peace. With the existing commerce among the nations, each dependent on every other, a war of any kind does injury to all. A nation at war destroys its own property throughout the world, and all the nations suffer. A neutral nation can no more afford to countenance a needless war than mobs burning its own cities and killing its own citizens. In New York, London, Berlin and Paris are business houses and representatives of every country in the world. How could any nation wish to destroy or to permit the destruction of these cities? . . .
Science has given us democracy, it has given us ample means of subsistence, it has given us commerce and intercommunication, and these three achievements are the principal factors which have lessened warfare and will eventually lead to its complete abolition. Other contributions of science, though less momentous, are by no means unimportant. Warfare is now in large measure applied science, and this tends towards its decrease. Wars between nations with scientific equipment and savage and barbarous peoples are no longer waged on equal terms and are of short, duration. The extermination, despoliation and subjugation of the non-Caucasian races may be the world's great tragedy, and in so far as some of these peoples are able to adopt our science there will be a readjustment which may be written in blood or may be a triumph of common sense and justice. However this may be, the invincibility that science has conferred on the western nations has made them safe from attack and invasion, and while it may on occasion have led to wanton aggression, it has, on the whole, limited warfare. If we call to mind the centuries of invasion and threats of invasion by Northmen, Ottomans and Saracens, we can appreciate the value of the means of defense which science has given to the civilized nations.
