Holding to the idea of many-sided interest, what justification is there for elective studies? To this, the reply must be made that in elementary and in a part of secondary education the principle of indiscriminate election must be rejected. The only rational election in secondary education, as already explained (65), is election among the various members of a group of similar studies. In this way the destination and ability of the pupil may be regarded, without sacrificing the needed many-sidedness. The case is different in higher education, however, for election and many-sidedness are here quite reconcilable. Higher education is the _comparative study_ of a few branches. Thus, for example, on the social side, the whole civilization of Greece is focussed now in her political history, now in her art, now in her language, now in her education, now in her philosophy. The student who studies any one of these subjects thoroughly gets a comparative view of the whole of Greek life. It is not necessary for him to study them all. The same is true of each important country or epoch. Every culture study is an eminence from which the whole is seen. Likewise in science, to study a typical form of life exhaustively by the comparative method gives one an insight into all related life, as well as many glimpses into physical and chemical science. In a large sense, therefore, we study all nature, whether we elect biology, physics, or chemistry, provided we use the comparative method of higher education. In the college or university, therefore, a large amount of election is justifiable. That would be a one-sided course which neglected entirely all social or all science studies. 90. Under favorable circumstances of time and opportunity, such as obtain in classical and other high schools, effort, as we know, is not restricted to the initial stimulation. Hence the question arises: In what sequence shall the aroused interests be further developed? Of instruction-material there is no lack; we must select and arrange, guided in the main by what was said on the conditions of many-sidedness and of interest. Thus to recapitulate: there must be progress from the simple to the more complex, and solicitous endeavor to make spontaneous interest possible. But in applying these principles we must not shut our eyes to the particular requirements and the difficulties in our way. 91. The empirical material of languages, history, geography, etc., calls for specific complications and series of ideas, together with the network of their interrelations. As to language, even words are complex wholes, made up of stems plus whatever elements enter into inflection and derivation, and further resolvable into single speech sounds. History has its time-series, geography its network of spatial relations. The psychological laws of reproduction determine the processes of memorizing and of retaining.