"The difference between us is that I am a man of the world, and you are a man of books."

"I am certain that I am a thinking thing, and that I have a body, and that I am distinct from my body."

"I perceived it was possible to arrive at knowledge highly useful in life; and that, instead of the speculative philosophy usually taught in the Schools, we might find a practical, by means of which, k…"

"I know that I exist, but I do not know what I am."

"The greatest good is to live with reason, and therefore, to live without passions."