On the basis of sense realism, Ratich anticipated many principles of modern pedagogy, but he was unsuccessful in applying his ideas. Comenius (1) produced texts for teaching Latin objectively, (2) crystallized his educational principles in the _Great Didactic_, and (3) attempted an encyclopædic organization of knowledge. He wished to make this knowledge part of the course at every stage of education, and, while he was not consistently inductive, he made a great advance in the use of this method. Through sense realism, rudimentary science was introduced into the elementary schools; the _Ritterakademien_ and the pietist schools stressed the subject; and professorships of science were founded in the universities. [Sidenote: Earlier realism a transition to sense realism.] [Sidenote: Opposition to the sciences.] =The Development of the Sciences and Realism.=--The realistic tendency did not pause with reviving the ideas represented by the words nor with the endeavor to bring the pupil into touch with the life he was to lead. The earlier realism seems to have been simply a stage in the process of transition from the narrow and formal humanism to a realism obtained through the senses, which may be regarded as the beginning of the modern movement to develop the natural sciences. Science had started to develop as early as the time of the schoolman, Roger Bacon (1214-1294), but for three centuries it was not kindly received. Even during the Renaissance the Church had continued to oppose it bitterly, because it tended to conflict with religious dogma, although this age did not object to the revival of the classics. Accordingly, the latter subject became strongly intrenched in educational tradition, and its advocates offered the most obstinate opposition to the sciences. Its numerous representatives struggled hard to keep the sciences out of education. [Sidenote: Development of physics and astronomy in the seventeenth century.]