This article provides a description of methodology of Jurgen Habermas and his analysis of positivism and Carl Popper's critical rationalism. Also, Habermas's attempt to develope a comprehensive rationality by the means of describing the three concerns of human kind and their relation with the knowledge of natural sciences, historical sciences and hermeneutics, and critical sciences is portrayed. Finally, the way in which Habermas used Gadamer's hermeneutics and Freud's psychoanalysis to develop these sciences along with the goals and limitations of each science is explained.
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