Different Images of Copernicus in the Views by Cohen and Kuhn

Both I.B.Cohen and Thomas Kuhn carried out researches on Copernicus,but they drew opposite conclusions on whether a Copernican Revolution existed.Their antithetical ideas lie in their difference on the definitions of Copernican Revolution,the Evaluation Criterion,and their analytical modes and the research aims on history of science.Cohen does not acknowledge the existence of Copernican Revolution because of his standpoint of historical view of positivism,while Copernican Revolution in Kuhn's eye is the result of his rational reconstruction with his scientific view of historicism.