It is undoubtedly depressing to have to recognize this universality of prejudice and to have to abandon the opinion sometimes held that the characteristics of herd belief are limited to the judgments of the vulgar. The selectness of a minority in no way guarantees it against the fallacies of the mob. A minority sufficiently unpopular is, in a sense, a mob in which smallness is compensated for by density. The moral vigour and fortitude which unpopular minorities enjoy are evidences of herd instinct in vigorous action; the less admirable liability to prejudice being a part of the same instinctive process is a necessary accompaniment. We may lay it down, then, as fundamental that all opinion among the members of a nation at war is liable to prejudice, and when we remember with what vehemence such opinion is pronounced and with what fortitude it is defended we may regard as at least highly probable that such opinion always actually is prejudiced—rests, that is to say, on instinct rather than reason. Now, it is common knowledge that in the present state of society opinion in a given country is always divided as to the justice of an actual war. All of it sharing the common characteristic of war opinion in being prejudiced, some will pronounce more or less clearly that the war is just and necessary, some will pronounce more or less clearly against that view; there will be a division into what we may call pro-national and anti-national currents of opinion, each accompanied respectively by its counterpart of what we may call anti-hostile and pro-hostile opinion. It is a significant fact that the relative development of pro-national and anti-national feeling varies according to the degree in which the given war is apprehended as dangerous. A {218} war apprehended as dangerous produces a more complete solution of the minor herds of society into the common body than does a war not so regarded; in consequence there is a nearer approach to homogeneity, and pro-national opinion is far in excess of anti-national opinion, which, if recognizable, is confined to insignificant minorities. A war regarded as not dangerous produces a less complete solution in the common body, a less degree of homogeneity, and allows anti-national opinion, that is, doubt of the justice of the war and opposition to the national policy, to develop on a large scale. These phenomena have been clearly visible in the history of recent wars. The South African War of 1899–1902 was not apprehended as dangerous in this country, and in consequence, though pro-national opinion prevailed among the majority, anti-national opinion was current in a large and respectable minority. The war of 1914–1918, regarded from the first as of the greatest gravity, gave to pro-national opinion an enormous preponderance, and restricted anti-national opinion within very narrow limits. The Russo-Japanese War provided an excellent double illustration of these mechanisms.