Sincerity is the indispensable ground of all conscientiousness, and by consequence of all heartfelt religion.

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

An organized product of nature is that in which all the parts are mutually ends and means.

Act in such a way that you will be worthy of being happy.

Philosophy stands in need of a science which shall determine the possibility, principles, and extent of human knowledge à priori.

Ghost stories are always listened to and well received in private, but pitilessly disavowed in public. For my own part, ignorant as I am of the way in which the human spirit enters the world and the way in which he goes out of it, I dare not deny the truth of many such narratives.

Each according to his own way of seeing things, seek one goal, that is gratification.