| The dissertation takes Modernity as the fundamental topic of Habermas' thought. After simply giving thought history of Modernity, it emphasizes his concept of communicative ration, moreover it tries to discuss his social evolution theory putted forward by reconstructed historical materialism. According to Habermas, the crux of modernity lies in that social systems controlled by purpose ration breaks away from dimension of rational communication, which results in "colony of life world". The project of communicative ration is to overstep the narrow form of modernity, by which demonstrates a new form of process ration, and reproof the Enlightenment movement's thought of modernity, i.e. reconstruction of society on basis of ration. Reconstructing historical materialism means stressing the logic of communicative ration along with social evolution process. |