Speculative interest becomes one-sided by confining itself to logic or to mathematics, mathematics perhaps only as treated by the old geometricians; or to metaphysics restricted possibly to one system; or to physics narrowed down perhaps to one hypothesis; or to pragmatic history. Æsthetic interest in one case is concentrated exclusively on painting and sculpture; in another on poetry, perhaps only on lyric or dramatic poetry; in still another on music, or perhaps only on a certain species of music, etc. Sympathetic interest is one-sided when a man is willing to live only with his social peers, or only with fellow-countrymen, or only with members of his own family; while a fellow-feeling for all others is wanting. Social interest grows one-sided if one gives himself up wholly to one political party, and measures weal or woe only by party success or failure. Religious interest becomes one-sided according to differences of creed and sect, to one of which allegiance is given, while those who hold a different view are regarded as unworthy of esteem. Much of this one-sidedness is brought about in later life by one’s vocation. But a man’s vocation must not isolate him. Yet this would happen if such narrowness should make headway in youth. 87. A still more detailed analysis of the varieties of one-sidedness would be possible; it is not needed, however, for ascertaining the position of the above-mentioned high school studies among the subjects of instruction calculated to stimulate interest. Languages, to begin with, form a part of the curriculum; but why among so many languages is the preference given to Latin and Greek? Obviously because of the literature and history opened through them. Literature with its poets and orators falls under æsthetic interest; history awakens sympathy with distinguished men and the weal and woe of society, indirectly contributing in either case even to religious interest. No better focus for so many different stimuli can be found. Even speculative interest is not slighted if inquiries into the grammatical structure of these languages are added. Moreover, the study of history does not stop with the ancients; the knowledge of literature also is widened that the various interests may be developed still more completely. History, if taught pragmatically, assists speculative interest from another direction. In this respect, however, mathematics has precedence; only, in order to effect a sure entrance and abiding results, it must unite with the natural sciences, which appeal at once to the empirical and the speculative interest.