armies and navies have been prepared, and which are exemplified by the present conflict. For purposes of classification we may roughly distinguish four kinds of wars, though, of course, in any given case a war is not likely to be quite clearly of any one of the four kind. With this proviso we may distinguish: (1) Wars of Colonisation; (2) Wars of Principle; (3) Wars of Self-Defence; (4) Wars of Prestige: Of these four kinds I should say that the first and second are fairly often justified; the third seldom, except as against an adversary of inferior civilisation; and the fourth, which is the sort to which the present war belongs, never. Let us consider these four kinds of war in succession.
By a "war of colonisation" I mean a war whose purpose is to drive out the whole population of some territory and replace it by an invading population of a different race. Ancient wars were very largely of this kind, of which we have a good example in the Book of Joshua. In modern times the conflicts of Europeans with American Indians, Maoris, and other aborigines in temperate regions, have been of this kind. Such wars are totally devoid of technical justification, and are apt to be more ruthless than any other war. Nevertheless, if we are to judge by results, we cannot regret that such wars have taken place. They have the merit, often quite fallaciously claimed for all wars, of leading in the main to the survival of the fittest, and it is chiefly through such wars that the civilised portion of the world has been extended from the neighbourhood of the Mediterranean to the greater part of the earth's surface. The eighteenth century, which liked to praise the virtues
