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.

He who has made great moral progress ceases to pray

Feminine traits are called weaknesses. People joke about them; fools ridicule them; but reasonable persons see very well that those traits are just the tools for the management of men, and for the use of men for female designs.

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.

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.

In every department of physical science there is only so much science, properly so-called, as there is mathematics.

Even a man's exact imitation of the song of the nightingale displeases us when we discover that it is a mimicry, and not the nightingale.