"I feel within me a will that is far more extensive than my understanding."

"I desire to live in peace and to continue the life I have begun, adopting as my motto 'to live well, one must live concealed'."

"It is not enough to possess a good mind; one must make good use of it."

"I resolved to feign that all the perceptions I had ever received were no truer than the illusions of my dreams."

"The mind is a substance whose whole essence or nature is to think, and which needs no place, nor depends on any material thing, in order to exist."