Freedom is the alone unoriginated birthright of man, and belongs to him by force of his humanity.

All the interests of my reason, speculative as well as practical, combine in the three following questions: 1. What can I know? 2. What ought I to do? 3. What may I hope?

Heaven has given human beings three things to balance the odds of life: hope, sleep, and laughter.

Do the right thing because it is right.

Suicide is not abominable because God prohibits it; God prohibits it because it is abominable.

Enlightenment is the liberation of man from his self-caused state of minority... Supere aude! Dare to use your own understanding!is thus the motto of the Enlightenment.

It is often necessary to make a decision on the basis of knowledge sufficient for action but insufficient to satisfy the intellect.