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.

Despair is the greatest of our errors.

Despair exaggerates not only our misery but also our weakness.

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

Whatever affection we have for our friends or relations, the happiness of others never suffices for our own.

All that causes one man to differ from another is a very slight thing. What is it that is the origin of beauty or ugliness, health or weakness, ability or stupidity? A slight difference in the organs, a little more or a little less bile. Yet this more or less is of infinite importance to men; and when they think otherwise they are mistaken.

We are very wrong to think that some fault or other can exclude virtue, or to consider the alliance of good and evil as a monstrosity or an enigma.