In a recently published treatise on natural philosophy, Ostwald,[344] a very distinguished German physical chemist, has discussed this question. He calls good “the actions that made easier the existence of other men.” But to what other men are we to apply this rule? “What is the size of the circle of altruistic love,” asked Ostwald. “The general feeling,” he said, “is that it should cover the family and the nation. The feeling that it should cover all humanity appears to most of us as a theoretical demand rather than something practical. And thus have not most of us the tendency to limit our altruistic actions much more in the case of men beneath us than in the case of our social comrades (Stadesgenossen)?” According to this formula, moral action would not stretch beyond our compatriots, and humanity as a whole would be excluded from it. Here we have entered on a problem relating to the principles of normal life. In former times, religion was the chief bond among men. Later on, religion gave way to patriotism, which in default of anything better still holds its place. Community of language unites the individuals of a nation, but the advance of civilisation has undermined the foundation of that source of differentiation. Naturally, when a number of men spoke only one and the same language, great solidarity was the result, as ideas spread only by language. But such a monoglottism is not the end of human progress. As means of communication have improved, the nations have been brought in contact with each other. The knowledge of foreign languages is an elementary necessity of modern life. And so the bonds of nationality certainly will become looser, in this respect following the bonds of family. The dislike that we have to people whose language we do not understand, becomes changed into a feeling of unity with them as soon as we can understand them. In that respect an active development is in progress, and we shall have to seek out some new principle on which to base international solidarity. A good deal has been made of the possession by different nations of the same culture, but the vagueness of the phrase has not been realised. Recognition of the true goal of life and of science as the only means by which that goal may be attained would form an ideal on which men might unite; they would group themselves around that, as in former days men were held together by religion.