[Sidenote: _Outlines of Educational Doctrine._] =His Work at Königsberg and Göttingen.=--In 1809 Herbart was called to the chair of philosophy at Königsberg, and there established his now historic pedagogical seminary and the small practice school connected with it. The students, who taught in the practice school under the supervision and criticism of the professor, were intending to become school principals and inspectors, and, through the widespread work and influence of these young Herbartians the educational system of Prussia and of every other state in Germany was greatly advanced. In his numerous publications at Königsberg, Herbart devoted himself chiefly to works on a system of psychology as a basis for his pedagogy. After serving nearly a quarter of a century here, he returned to Göttingen as professor of philosophy, and the last eight years of his life were spent in expanding his pedagogical positions. Here he issued the first edition of his _Outlines of Educational Doctrine_ (1835), which gives an exposition of his educational system when fully matured. It contains brief references to his mechanical metaphysics and psychology, but is a most practical and well-organized discussion of the educational process. [Sidenote: An after-thought.] [Sidenote: Mind built up by outside world.] [Sidenote: Genesis and combination of ideas.] [Sidenote: ‘Apperception.’] =Herbart’s Psychology.=--Herbart’s metaphysical psychology seems to have been an after-thought developed to afford a basis for the method of pedagogical procedure that he had worked out of his tutorial experience and his acquaintance with the Pestalozzian practice. But some explanation of this elaborate psychology may serve to make clearer his educational principles. For the most part he holds that the mind is built up by the outside world, and he is generally supposed to have left no place for instincts or innate characteristics and tendencies. With him the simplest elements of consciousness are ‘ideas,’ which are atoms of mind stuff thrown off from the soul in endeavoring to maintain itself against external stimuli. Once produced by this contact of the soul with its environment, the ideas become existences with their own dynamic force, and constantly strive to preserve themselves. They struggle to attain as nearly as possible to the summit of consciousness, and each idea tends to draw into consciousness or heighten those allied to it, and to depress or force out those which are unlike. Each new idea or group of ideas is heightened, modified, or rejected, according to its degree of harmony or conflict with the previously existing ideas. In other words, all new ideas are interpreted through those already in consciousness. In accordance with this principle, which Herbart called ‘apperception,’ the teacher can secure interest and the attention of the pupil to any new idea or set of ideas and have him retain it, only through making use of his previous body of related knowledge.