Hence national self-consciousness can never develop except in the form of an idea of strong affective tone, that is to say a sentiment. Hence, whenever we speak of national self-consciousness or the idea of the nation as a powerful factor in its life, the sentiment is implied, and I have implied it when using these expressions hitherto. This national sentiment, which, if we use the word in its widest sense, may be called patriotism, is, like all the other group sentiments, developed by way of extension of the self-regarding sentiment of the individual to the group, and may be further complicated and strengthened by the inclusion of other tendencies. A point of especial importance is that this great group sentiment can hardly be developed otherwise than by way of extension of sentiments for smaller included groups, the family especially. For the idea of the nation is too difficult for the grasp of the child's mind, and cannot, therefore, become the object of a sentiment until the intellectual powers are considerably developed. Hence the development of a family sentiment, or of one for some other small easily conceived group, is essential for the development in the child of those modes of mental action which are involved in all group feeling and action. For this reason the family is the surest, perhaps essential, foundation of national life; and national self-consciousness is strongest, where family life is strongest.
The development of the group spirit in general and of national self-consciousness in particular is favoured by, and indeed dependent upon, conditions similar to those which develop the self-consciousness of individuals. Here is another striking point of the analogy between the individual and the national mind. Passing over other conditions, let us notice one, the most important of all. The individual's consciousness of self is developed chiefly by intercourse with other individuals--by imitation, by conflict, by compulsion, and by co-operation. Without such intercourse it must remain rudimentary. The individual's conception of himself is perpetually extended by his increasing knowledge of other selves; and his knowledge of those other selves grows in the light of his knowledge of himself. There is perpetual reciprocal action. The same is true of peoples. A population living shut off, isolated from the rest of the world, within which no distinctions of tribe and race existed, would never become conscious of itself as one people and, therefore, would not become a nation. Some such conditions obtained for long ages among the pastoral hordes of the central Eurasian Steppes, which, so long as they remained there, have never formed a nation; and the same was true of the tribes of Arabia, until Mahomet impelled them by his religion of the sword to hurl themselves upon neighbouring peoples.