Superficial knowledge ... is hurtful to those who possess true genius; for it necessarily draws them away from their main object, wastes their industry over details and subjects foreign to their needs and natural talent, and lastly does not serve, as they flatter themselves, to prove the breadth of their mind. In all ages there have been men of very moderate intelligence who knew much, and so on the contrary, men of the highest intelligence who knew very little. Ignorance is not lack of intelligence, nor knowledge a proof of genius.

The wicked are always surprised to find that the good can be clever.

We are less hurt by the contempt of fools than by the lukewarm approval of men of intelligence.

Courage is adversity's lamp.

The falsest of all philosophies is that which, under the pretext of delivering men from the embarrassment of their passions, counsels idleness and the abandonment and neglect of themselves.

It is of no use to possess a lively wit if it is not of the right proportion: the perfection of a clock is not to go fast, but to be accurate.

We are so presumptuous that we think we can separate our personal interest from that of humanity, and slander mankind without compromising ourselves.