关键词: 正义, 幸福论, 强者政治学

Abstract: The challenge that Plato has been facing is a fundamental theoretical problem. Sophists think no one can prove that people of justice without power and influence are happy and people who are not justice are not happy. In answering this question, first Plato exchanged the implication of justice,as a result, the so-called real justice that he gained, namely intrinsic justice, is exactly unjust for many people. Plato thank that the man controlling power should be a philosopher,but the philosopher is also unhappy in the country of justice. For the wise persons who believing sophists are more and more, it has not only significance of science but also significance of reality that Plato's political task is convinced or not.

Key words: justice, theory of happiness, politics of the strong man