“Stubborn and ardent clinging to one’s opinion is the best proof of stupidity.”

One may be humble out of pride.

My trade and art is to live.

There is a sort of gratification in doing good which makes us rejoice in ourselves.

There is no pleasure to me without communication: there is not so much as a sprightly thought comes into my mind that it does not grieve me to have produced alone, and that I have no one to tell it to.

If you don’t know how to die, don’t worry; Nature will tell you what to do on the spot, fully and adequately.

There is no desire more natural than the desire for knowledge.

A wise man sees as much as he ought, not as much as he can.

There is no conversation more boring than the one where everybody agrees.

The soul which has no fixed purpose in life is lost; to be everywhere, is to be nowhere.

Ambition is not a vice of little people.

Marriage is like a cage; one sees the birds outside desperate to get in, and those inside equally desperate to get out.

Nothing is so firmly believed as what we least know.

It is the mind that maketh good or ill, That maketh wretch or happy, rich or poor.

A good marriage would be between a blind wife and a deaf husband.

We can be knowledgable with other men’s knowledge but we cannot be wise with other men’s wisdom.

The public weal requires that men should betray, and lie, and massacre.

One thing I did was grow up as an ardent naturalist. I never grew out of my bug period.