“If you want good laws, burn those you have and make new ones.”

“Those who can make you believe absurdities, can make you commit atrocities.”

“The most important decision you make is to be in a good mood.”

“I have received your new book against the human race, and thank you for it. Never was such a cleverness used in the design of making us all stupid. One longs, in reading your book, to walk on all fours. But as I have lost that habit for more than sixty years, I feel unhappily the impossibility of resuming it. Nor can I embark in search of the savages of Canada, because the maladies to which I am condemned render a European surgeon necessary to me; because war is going on in those regions; and because the example of our actions has made the savages nearly as bad as ourselves. [in response to Rousseau's "The Social Contract"]”

“Our wretched species is so made that those who walk on the well-trodden path always throw stones at those who are showing a new road.”

“Whatever you do, crush the infamous thing, and love those who love you.”

“He showed, in a few words, that it is not sufficient to throw together a few incidents that are to be met with in every romance, and that to dazzle the spectator the thought should be new, without being farfetched; frequently sublime, but always natural; the author should have a thorough knowledge of the human heart and make it speak properly; he should be a complete poet, without showing an affectation of it in any of the characters of his piece; he should be a perfect master of his language, speak it with all its pruity and with the utmost harmony, and yet so as not to make the sense a slave to the rhyme. Whoever, added he, neglects any one of these rules, though he may write two or three tragedies with tolerable success, will never be reckoned in the number of good authors.”