We desire truth, and find within ourselves only uncertainty. We seek happiness, and find only misery and death. We cannot but desire truth and happiness, and are incapable of certainty or happiness.

We know the truth not only through our reason but also through our heart. It is through the latter that we know first principles, and reason, which has nothing to do with it, tries in vain to refute them.

We are so presumptuous that we wish to be known to all the world, even to those who come after us; and we are so vain that the esteem of five or six persons immediately around us is enough to amuse and satisfy us.

When we do not know the truth of a thing, it is good that there should exist a common error which determines the mind of man, as, for example, the moon, to which is attributed the change of seasons, the progress of diseases, etc. For the chief malady of man is a restless curiosity about things which he cannot understand; and it is not so bad for him to be in error as to be curious to no purpose.

The least movement is of importance to all nature. The entire ocean is affected by a pebble.

Instead of complaining that God had hidden himself, you will give Him thanks for having revealed so much of Himself.

Contradiction is not a sign of falsity, nor the lack of contradiction a sign of truth.