When I consider this carefully, I find not a single property which with certainty separates the waking state from the dream. How can you be certain that your whole life is not a dream?

Neither divine grace nor natural knowledge ever diminishes freedom.

There is a great difference between mind and body insomuch as body is by nature always divisible, and the mind is entirely indivisible.

The principal use of prudence, of self-control, is that it teaches us to be masters of our passions, and to so control and guide them that the evils which they cause are quite bearable, and that we even derive joy from them all.

The senses deceive from time to time, and it is prudent never to trust wholly those who have deceived us even once.

Even if I were to suppose that I was dreaming and whatever I saw or imagined was false, yet I could not deny that ideas were truly in my mind.

An optimist may see a light where there is none, but why must the pessimist always run to blow it out?