If we could see ourselves... as we really are, we should see ourselves in a world of spiritual natures, our community which neither began at birth nor will end with the death of the body.

Morality is not properly the doctrine of how we may make ourselves happy, but how we may make ourselves worthy of happiness.

Things which we see are not by themselves what we see ... It remains completely unknown to us what the objects may be by themselves and apart from the receptivity of our senses. We know nothing but our manner of perceiving them.

. . . as to moral feeling, this supposed special sense, the appeal to it is indeed superficial when those who cannot think believe that feeling will help them out, even in what concerns general laws: and besides, feelings which naturally differ infinitely in degree cannot furnish a uniform standard of good and evil, nor has any one a right to form judgments for others by his own feelings. . . .

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

Even the song of birds, which we can bring under no musical rule, seems to have more freedom, and therefore more for taste, than a song of a human being which is produced in accordance with all the rules of music; for we very much sooner weary of the latter, if it is repeated often and at length. Here, however, we probably confuse our participation in the mirth of a little creature that we love, with the beauty of its song; for if this were exactly imitated by man (as sometimes the notes of the nightingale are) it would seem to our ear quite devoid of taste.

A lie is the abandonment and, as it were, the annihilation of the dignity by man.