Duty is the necessity to act out of reverence for the law.

Prudence reproaches; conscience accuses.

A categorical imperative would be one which represented an action as objectively necessary in itself, without reference to any other purpose.

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.

The schematicism by which our understanding deals with the phenomenal world ... is a skill so deeply hidden in the human soul that we shall hardly guess the secret trick that Nature here employs.

The infinitude of creation is great enough to make a world, or a Milky Way of worlds, look in comparison with it what a flower or an insect does in comparison with the Earth.

Happiness, though an indefinite concept, is the goal of all rational beings