I had therefore to remove knowledge, in order to make room for belief.

Out of the crooked timber of humanity, no straight thing was ever made.

So act that your principle of action might safely be made a law for the whole world.

Act in such a way that you treat humanity, whether in your own person or in the person of any other, never merely as a means to an end, but always at the same time as an end.

Intuition and concepts constitute... the elements of all our knowledge, so that neither concepts without an intuition in some way corresponding to them, nor intuition without concepts, can yield knowledge.