Rousseau's beliefs covered many ideas of life. He believed that humans were born good but social interaction changed us, making us bad and corrupt. So we are all born as innocents. This is contrary to Christian religious beliefs that we are born with original sin. We are born with natural differences, like skill and ability. These are fine, but they eventually cause differences in wealth and property. These differences are called "artificial differences." These artificial differences influence social interaction and cause jealousy, envy, and contempt. This is thought of as the Fall.
What set Rousseau apart from other philosophers is that he believed this could be fixed. Not only did he believe that it could be fixed, but it could only be fixed through politics. He believed the right government would supervise all individuals very carefully and there would be very little personal property. Wealth would be spread fairly even to destroy the artificial differences.
There are some similarities between communism and Rousseau's perfect government, like ownership and sharing of wealth evenly.
Rousseau once said, "His fellows shall force him to be free." To explain that, Rousseau supported the idea of general will. Now many believe this leaves out minorities.