Happiness is not an ideal of reason, but of imagination.

We are not rich by what we possess but by what we can do without.

Experience without theory is blind, but theory without experience is mere intellectual play.

Whereas the beautiful is limited, the sublime is limitless, so that the mind in the presence of the sublime, attempting to imagine what it cannot, has pain in the failure but pleasure in contemplating the immensity of the attempt.

All thought must, directly or indirectly, by way of certain characters, relate ultimately to intuitions, and therefore, with us, to sensibility, because in no other way can an object be given to us.

In law a man is guilty when he violates the rights of others. In ethics he is guilty if he only thinks of doing so.

The only objects of practical reason are therefore those of good and evil. For by the former is meant an object necessarily desired according to a principle of reason; by the latter one necessarily shunned, also according to a principle of reason.

But although all our knowledge begins with experience, it does not follow that it arises from experience.

Out of timber so crooked as that from which man is made nothing entirely straight can be carved.

Metaphysics is a dark ocean without shores or lighthouse, strewn with many a philosophic wreck.

It is not God's will merely that we should be happy, but that we should make ourselves happy.

It is beyond a doubt that all our knowledge that begins with experience.

Perpetual peace is only found in the graveyard.