Post-modernism as the orientation in social sciences opposes modernism, and its noncredulity in reason, and empiria. Reason, and empiria are a solid basis for knowledge acquisition. Credulity in reason means having the agreement of all rational individuals, which post-modernists oppose and do not believe in such agreement. Post-modernists do not believe in general truth existence due to the impact of subjective facts such as faith, gender, culture, and personal attitudes. There is no objective reality as well. Lyotard does not believe in metanarratives such as Marxism or Christianity so that he gives advantage to micro narratives in the sense of subjective stories, which have got he meaning for some people in determined space, and time. He introduces the dichotomy between scientific, and narrative knowledge, oppose them to each other, but he also indicates to their connection. Lyotard also opposes modern concept of language as per which the language has got the meaning because of the fact each word stands for something which exists. He introduces Wittgenstein's comprehension of language as per which words are not given meaning in correspondence with the world, but from the relationships with other words. Communication in meaningrelated sense is possible due to the existence of the rules of the game. Lyotard also criticises Marxism, and liberalism as great metanarratives Both orientations experienced its collapse during the previous century: liberal capitalism entered a great economic crisis, and culminated in fascism, while Marxism based on socialism experiences its end by the dissolution of Eastern bloc. Marxism is an intellectual antipode to liberalism, deadly enemy; the only common core of theirs is the ideal of freedom.