Freedom is the alone unoriginated birthright of man, and belongs to him by force of his humanity; and is independence on the will and co-action of every other in so far as this consists with every other person's freedom.

Innocence is indeed a glorious thing; but, unfortunately, it does not keep very well and is easily led astray.

All false art, all vain wisdom, lasts its time but finally destroys itself, and its highest culture is also the epoch of its decay.

Have the courage to use your own reason- That is the motto of enlightenment. "Foundations of the Metaphysics of Morals" (1785)

There can be no doubt that all our knowledge begins with experience.

Reason can never prove the existence of God.

We assume a common sense as the necessary condition of the universal communicability of our knowledge, which is presupposed in every logic and every principle of knowledge that is not one of skepticism.