 In the "Discourse on the Arts and Sciences" Rousseau argues that the arts and sciences have not been beneficial to humankind, because they arose not from authentic human needs but rather as a result of pride and vanity.Moreover, the opportunities they create for idleness and luxury have contributed to the corruption of man.He proposed that the progress of knowledge had made governments more powerful and had crushed individual liberty; and he concluded that material progress had actually undermined the possibility of true friendship by replacing it with jealousy, fear, and suspicion.