Rousseau, Second Discourse I

What is it to know the nature of man?

Rousseau takes up the idea of the natural equality of man, the idea taken as self-evident in the Declaration of Independence. He does so because it is clear that we are not equal now, which raises the question: are these inequalities natural, or are they artificial and conventional? If they are natural, then you must make a case for tinkering with or trying to alter them. If they are not, then not so much.

What are the natural differences among men and are they politically relevant?