“I have chosen to be happy because it is good for my health.”

“Clearly,” I said, “we should choose not to have good sense, if that good sense contributes to our misery.” Everyone agreed with me, and yet I found no one who wanted to accept the bargain of becoming ignorant in order to become content. From this I concluded that though we greatly value happiness, we place even greater value on reason.But yet, upon reflection, it seems that to prefer reason to happiness is to be quite insane.”

“We all look for happiness, but without knowing where to find it: like drunkards who look for their house, knowing dimly that they have one”

“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"]”

“Being unable to make people more reasonable, I preferred to be happy away from them”

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

“Fools have a habit of believing that everything written by a famous author is admirable. For my part I read only to please myself and like only what suits my taste.”