15 The philosophical disciplines are to be taught in such a way that the students are first of all led to acquire a solid and coherent knowledge of man, the world, and of God, relying on a philosophical patrimony which is perennially valid and taking into account the philosophical investigations of later ages. This is especially true of those investigations which exercise a greater influence in their own nations. Account should also be taken of the more recent progress of the sciences. The net result should be that the students, correctly understanding the characteristics of the contemporary mind, will be duly prepared for dialogue with men of their time. The history of philosophy should be so taught that the students, while reaching the ultimate principles of the various systems, will hold on to what is proven to be true therein and will be able to detect the roots of errors and to refute them. In the very manner of teaching there should be stirred up in the students a love of rigorously searching for the truth and of maintaining and demonstrating it, together with an honest recognition of the limits of human knowledge. Attention must be carefully drawn to the necessary connection between philosophy and the true problems of life, as well as the questions which preoccupy the minds of the students. Likewise students should be helped to perceive the links between the subject-matter of philosophy and the mysteries of salvation which are considered in theology under the higher light of faith.
Source: Optatam Totius (Vatican.va)