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.

Live your life as though your every act were to become a universal law.

I assert that, in any particular natural science, one encounters genuine scientific substance only to the extent that mathematics is present.

Apart from moral conduct, all that man thinks himself able to do in order to become acceptable to God is mere superstition and religious folly.

[A ruler is merely] the trustee of the rights of other men and he must always stand in dread of having in some way violated these rights.

Everything in nature acts in conformity with law.

That Logic has advanced in this sure course, even from the earliest times, is apparent from the fact that, since Aristotle, it has been unable to advance a step, and thus to all appearance has reached its completion.