In order to support his revolutionary view on scientific change, Kuhn suggests that there exist two separate aspects of the theory-change from Newtonian to Einsteinian physics that support his incommensurability thesis. For the evidence of his thesis, Kuhn offers the conceptual change in the meaning of the notion of “mass” in the theory-change. And he claims the absence of any neutral observational basis to evaluate the strengths of the two theories. This essay argues that these two cases fail to support his incommensurability thesis.