In spite of its great popularity and extensive influence, Rousseaus famous saying of “Man is born free, and everywhere he is in chains” has always been puzzling for generations of scholars up to recent days, due to its extreme obscurity and diversified ways of interpretation. One important passage in Rousseaus Discourse on the sciences and arts contributes to the clarification of this saying, as well as to the revelation of Rousseaus ultimate intention within all writings of his life. Rousseau accurately discerns the intellectuals’ innovations in the concept of society, and points out the inner connection of the sciences and arts to commercial spirit, which is held in high esteem in the enlightenment. The diversified and careful sayings which Rousseau takes to address the “earthly powers”, “civilized peoples” and “talents”, demonstrate Rousseaus insightful observation of the quality and innate character of enlightenment.