This edition is, like the second edition (1910), a reprint, with a few verbal corrections, of the first edition (1908). I tried in 1908 to make two main points clear. My first point was the danger, for all human activities, but especially for the working of democracy, of the 'intellectualist' assumption, 'that every human action is the result of an intellectual process, by which a man first thinks of some end which he desires, and then calculates the means by which that end can be attained' (p. 21). My second point was the need of substituting for that assumption a conscious and systematic effort of thought. 'The whole progress,' I argued, 'of human civilisation beyond its earliest stages, has been made possible by the invention of methods of thought which enable us to interpret and forecast the working of nature more successfully than we could, if we merely followed the line of least resistance in the use of our minds' (p. 114). In 1920 insistence on my first point is not so necessary as it was in 1908. The assumption that men are automatically guided by 'enlightened self-interest' has been discredited by the facts of the war and the peace, the success of an anti-parliamentary and anti-intellectualist revolution in Russia, the British election of 1918, the French election of 1919, the confusion of politics in America, the breakdown of political machinery in Central Europe, and the general unhappiness which has resulted from four years of the most intense and heroic effort that the human race has ever made. One only needs to compare the disillusioned realism of our present war and post-war pictures and poems with the nineteenth-century war pictures at Versailles and Berlin, and the war poems of Campbell, and Berenger, and Tennyson, to realise how far we now are from exaggerating human rationality. It is my second point, which, in the world as the war has left it, is most important. There is no longer much danger that we shall assume that man always and automatically thinks of ends and calculates means. The danger is that we may be too tired or too hopeless to undertake the conscious effort by which alone we can think of ends and calculate means.