[T] It is important that it should be quite clear that we have been speaking here of the reaction of the general body of a nation to the occurrence of war, and not of the reasons for which a given war was undertaken. In England and in Germany the feeling of the people that the late war was just and necessary was equally intense and equally a direct consequence of the danger to the herd it represented. It was therefore a non-rational instinctive response without reference to objective justice in either case. Had the threat to the herd on either side seemed less grave, opinion as to the justice of the war would in that country have been correspondingly more divided. By her calculated truculence in the years before the war Germany—intending doubtless to intimidate a decaying people—had made it certain that when the threat to this country did come it should be apprehended at once as dangerous to the last degree, and had thus herself organized the practical unanimity of her chief enemy. All such reactions upon the outbreak of war are instinctively determined. It is the burden of the statesman that his decision in a crisis in favour of war _automatically_ renders impossible _rational_ confirmation by the people. We thus arrive at the discouraging conclusion that in a belligerent country all opinion in any way connected with the war is subject to prejudice, either pro-national or anti-national, and is very likely in consequence to be of impaired validity. Must we then conclude further that speculation upon war themes is so liable to distortion that reasoned judgments of any practical value are impossible? Now, it is guidance in just such a difficulty as this that a psychology having any pretensions to be called practical may fairly be expected to yield, and psychology does in fact provide certain broad precautionary principles, which, although by no means infallible guides, do profess to be able to keep within bounds the disturbing effects of prejudice on judgment and so render possible the not wholly unprofitable discussion even of matters the most deeply implicated by war-time passion.