Reasons of space make it impossible to survey the further developments to which social organization is subject under the sway of locality. It is, perhaps, less essential to insist on them here, because, whereas totemic society is a thing which we civilized folk have the very greatest difficulty in understanding, we all have direct insight into the meaning of a territorial arrangement; since, from the village community up to the modern state, the same fundamental type of social structure obtains throughout. Besides local contiguity, however, there is a second principle which greatly helps to shape the social order, as soon as society is sufficiently advanced in its arts and industries to have taken firm root, so to speak, on the earth's surface. This is the principle of private property, and especially of private property in land. The most fundamental of class distinctions is that between rich and poor. That between free and slave, in communities that have slavery, is not at first sight strictly parallel, since there may be a class of poor freemen intermediate between the nobles and the slaves; but it is obvious that in this case, too, private property is really responsible for the mode of grading. Or sometimes social position may seem to depend primarily on industrial occupation, the Indian caste-system providing an instance in point. Since, however, the most honourable occupations in the long run coincide with those that pay best, we come back once again to private property as the ultimate source of social rank, under an economic system of the more developed kind. In this brief sketch it has been impossible to do more than hint how social organization is relative to numbers, which in their turn are relative to the skill with which the food-quest is carried on. But if, up to a certain point, it be true that the structure of society depends on its mass in a more or less physical way, there is to be borne in mind another aspect of the matter, which also has been hinted at as we went rapidly along. A good deal of intelligence has throughout helped towards the establishing of the social order. If social organization is in part a natural result of the expansion of the population, it is partly also, in the best sense of the word, an artificial creation of the human mind, which has exerted itself to devise modes of grouping whereby men might be enabled to work together in larger and ever larger wholes.