This relation is not an isolated phenomenon; on the contrary, it is entirely in the line of experience. Language is the most important factor which determines usage and influences character; this result is effected through the literature, oral or written, with which, in virtue of the possession of a particular speech, any given people is brought into contact. In this process race goes for little. Borrowing the tongue of a superior race, a subject population receives also the songs, tales, habits, inclinations which go with the speech; human nature, in all times essentially imitative, copies qualities which are united with presumed superiority; to this process not even racial hostility is a bar; assimilation and transmission go on in spite of hatred directed against the persons who are the object of the imitation; such a process may be observed in the recent history of Ireland. Reception of new ideas, however, though promoted by the possession of a common language constituting a means of exchange, is not limited by its absence; on the contrary, in all historical time among contiguous races takes place a transference of ideas which dislike and even warfare do not prevent. Here the law seems to be that the lower culture has relatively little effect on the higher with which it is in contact, while the superior civilization speedily influences an inferior one. Nor is the effect confined to the higher classes of any given society; beginning with these, the new knowledge descends through all ranks, and everywhere carries its transforming influence. What is true of written literature in a less degree is true of oral; songs and tales, rites and customs, beliefs and superstitions, diffuse themselves from the civilization which happens to be in fashion, with a rapidity greater or less according to the interworking of a multitude of modifying forces. In the other direction, from the lower culture to the higher, exchange is slow, albeit likely to be promoted, in certain cases, by peculiar conditions, such as the deliberate literary choice which seeks opportunity for archaistic representation, or the respect which an advanced race may have for the magical ability of a simple tribe, believed to be nearer to nature, and therefore more likely to remain in communion with natural forces.