"I have long ago observed that in order to study the truth, it is necessary once in the course of our life to demolish everything completely and start again from the foundations."

"The existence of God is demonstrated by the fact that I have an idea of a perfect being."

"It is not enough to know, one must also apply; it is not enough to wish, one must also do."

"I have always taken the greatest pleasure in seeking out and acquiring knowledge."

"I entirely abandoned the study of letters, resolving to seek no other science than that which could be found in myself, or at least in the great book of the world."