The novel use of a word that is now a quite regular part of the language may in many cases first be ascribed to a distinguished writer. Shakespeare is full of expressions which have since, and because of his use of them, become literally household words. Many words that have now a general application arose out of a peculiar local situation, myth, or name. "Boycott" which has become a reasonably intelligible and universal word, only less than fifty years ago referred particularly and exclusively to Boycott, a certain unpopular Irish landowner who was subjected to the kind of discrimination for which the word has come to stand. "Burke" used as a verb has its origin in the name of a notorious Edinburgh murderer. Characters in fiction or drama, history or legend come to be standard words. Everyone knows what we mean when we speak of a Quixotic action, a Don Juan, a Galahad, a Chesterfield. To tantalize arises from the mythical perpetual frustration of Tantalus in the Greek story. Expressions that had a special meaning in the works of a philosopher or litterateur come to be generally used, as "Platonic love."[1] Again words that arise as mere popular witticisms or vulgarisms may be brought into the language as permanent acquisitions. "Mob," now a quite legitimate word, was originally a shortening of _mobile vulgum_, and was, only a hundred years ago, suspect in polite discourse. [Footnote 1: Though this is very loosely and inaccurately used.] Outside the deliberate invention by scientists of terms for the new relations they have discovered, more or less spontaneous variation in the use of words and their unconscious assimilation by large numbers with whose other language habits they chance to fit, is the chief source of language growth. One might almost say words are wrenched from their original local setting, and given such a generalized application that they are made available for an infinite complexity of scientific and philosophical thought. UNIFORMITIES IN LANGUAGE. Thus far we have discussed changes in language from the psychological viewpoint, that is, we have considered the human tendencies and habits which bring about changes in the articulation and meaning, in the sound and the sense, of words. It is evident from these considerations that there can be no absolute uniformity in spoken languages, not even in the languages of two persons thrown much together. Within a country where the same language is ostensibly spoken, there are nevertheless differences in the language as spoken by different social strata, by different localities. There are infinite subtle variations between the articulation and the word uses of different individuals. There are languages within languages, the dialects of localities, the jargon of professional and trade groups, the special pronunciations and special and overlapping vocabularies of different social classes.