There is nothing so absurd that some philosopher has not already said it.

It is of no avail to know what is about to happen; for it is a sad thing to be grieved when grief can do no good.

Virtue is a habit of the mind, consistent with nature and moderation and reason.

Every generous action loves the public view; yet no theatre for virtue is equal to a consciousness of it.

Oh, how great is the power of truth! which of its own power can easily defend itself against all the ingenuity and cunning and wisdom of men, and against the treacherous plots of all the world.

The following passage is one of those cited by Copernicus himself in his preface to De Revolutionibus: "The Syracusan Hicetas, as Theophrastus asserts, holds the view that the heaven, sun, moon, stars, and in short all of the things on high are stationary, and that nothing in the world is in motion except the earth, which by revolving and twisting round its axis with extreme velocity produces all the same results as would be produced if the earth were stationary and the heaven in motion. . . ."

The man who commands efficiently must have obeyed others in the past, and the man who obeys dutifully is worthy of someday being a commander.