In the essay, we will discuss the problem whether Davidson understands what Kuhn means by “incommensurable”? At the beginning of this book, the background should be mentioned that the term “incommensurability” —meaning the impossibility of comparison by a common measure —has its origin in mathematics, but its current philosophical usage dates back to Kuhn. Hard as it may be to credit, in my opinion, the incommensurability thesis has been one of the main sources of relativistic interpretations of Kuhn. In fact, Kuhn discusses the term "incommensurability" in more details in the postscript of his book. He says that “men who hold incommensurable viewpoints (should) be thought of as members of different language communities.” It clearly shows that Kuhn’s relativism rests on his assumption that scientific theories cannot be compared or assessed independently of the paradigms in which they are embedded, and each paradigm acts as a unique language. This is why Kuhn is criticized by Davidson. To illustrate the paradoxical view he criticizes, Davidson argues that “according to Kuhn, scientists operating in different scientificend traditions (within different 'paradigms') work in different worlds.” Therefore, here is an odd that if there is at most one world, “these pluralities are metaphorical or merely imagined.” However, Kuhn actually gives his another clearest assertion. In the postscript of the book, he says that “only philosophers have seriously misconstrued the intent of these parts of my argument.” When we try to find the mistake made by these “philosophers”, Kuhn presents another deeper problem. He claims how two men can hope to talk together under the incommensurable viewpoints. To this question, Kuhn puts out his view that “what the participants in a communication breakdown can do is (to) recognize each other as members of different language communities and then become translators.” Obviously, “translation” as a method has broken through the dilemma caused by incommensurability. So we can say that Kuhn does not equate incommensurability with a total breakdown of translation. Whereas, in Dacidson’s opinion, ‘incommensurable’ is not ‘intertranslatable’ in Kuhn’s words. He goes on to argue that we could never be in a position to judge others who use radical concepts distinct from ours. In his book, he says that “conceptual relativism…are not so extreme but that the changes and the contrasts can be explained and described using the equipment of a single language.” It can be inferred that Dacidson and Kuhn arrive at the same conclusion. In a word, Davidson misunderstands what Kuhn means by “incommensurable”.