A volume, and a very valuable one, might be written on the evolution of this idea of Humanity in history.  We should need in the first place to analyse, with some care, in what sense it is in each case used.  There is the simple sense of brotherhood such as we know to be deeply felt among our allies in Russia.  Of this there must have been germs from the earliest appearance of mankind upon earth.  It is one of those most precious things which the development of wealth and class and distinctive culture has tended to blunt in more elaborate civilizations.  But when we consider that the full conception of Humanity involves a knowledge of man’s evolution, his growth in power, and organization throughout history, as well as the simple but indispensable sense of man’s brotherhood, we shall see how long a road the Russian moujik—­as well as multitudes of his fellows in all other lands—­must travel before he comes in view of the goal.  In the fuller sense of a self-conscious and developing being, the idea of Humanity first appears with the Stoics, after the Greeks had put their leaven of abstract thought into the world.  The whole inhabited world as the City of Man was the Stoic ideal, and it embraced both the idea of the [Greek:  polis] which Platonic and Aristotelian thought had reached in the fourth century B.C., and the extension to the rest of mankind which was in the air just before the Christian era.  Christianity affected the conception in a twofold manner.  On the one hand it limited it, for the Stoic City of Man became the City of God, who was to be sought and worshipped in one prescribed order.  On the other hand it deepened it, for the springs of a common humanity were found to go beneath the superficial facts of a citizen life into the depths of souls which have identical relations with eternal things, with sin and suffering and hopes of the future.

It is not till after the outburst of science in the fifteenth and sixteenth centuries, after that reawakening of the hopes of human powers which takes our minds back to the Greeks, that we find the conception of Humanity appearing in something like the form in which we can now imagine it.  It will have been gathered from our chapter on Science and Philosophy how essential is the growth of organized thought to the realization of any unity in a progressive world.  For the realm of thought is the only one in which no distinctions of race or nation are possible, but it must be thought in which agreement is reached.  So long as men can differ, as they still do, on questions of human affairs, politics, social arrangements, or even archaeological matters where race or national predominance is involved, so far science does not exert her unifying sway.  But in mathematics, physics, chemistry, all the matters in which it is impossible for a man to take another view because he is a Frenchman or a German—­here we reach a haven of intellectual peace; and these calm waters are spreading over the world, in spite of the tempests.