A citizen should render to the state all the services he can as soon as the sovereign demands them.

The problem is to find a form of association which will defend and protect with the whole common force the person and goods of each associate, and in which each, while uniting himself with all, may still obey himself alone, and remain as free as before.

Too much apparatus, designed to guide us in experiments and to supplement the exactness of our senses, makes us neglect to use those senses...The more ingenious our apparatus, the coarser and more unskillful are our senses. We surround ourselves with tools and fail to use those which nature has provided every one of us.

The empire of woman is an empire of softness, of address, of complacency. Her commands are caresses, her menaces are tears.

There exists one book, which, to my taste, furnishes the happiest treatise of natural education. What then is this marvelous book? Is it Aristotle? Is it Pliny, is it Buffon? No-it is Robinson Crusoe.

The first step towards vice is to shroud innocent actions in mystery, and whoever likes to conceal something sooner or later has reason to conceal it.

He who has the base necessities of life should pay nothing; taxation on him who has a surplus may, if need be; extend to everything beyond necessities.