This paper expounds the basis of the Newton's laws and the universal gravitation law as well as the Coulomb's law established，the basis of several important physical quantities introduced，finally discusses how to properly evaluate the symmetry and the conservation law in the college physics teaching. The purpose of this paper is to express a kind of teaching ideas，namely，to clearly expound or profound interpret for the rich physical thoughts and the special way of thinking in physics，is an important embody of the academic level of a physics course，so the efforts to enhance the academic level of physics courses should become an important aspect of improving the quality of the college physics teaching.