Xinli Wang

Against the received translation-failure interpretation, this book presents a presuppositional interpretation of incommensurability, that is, the thesis of incommensurability as cross-language communication breakdown due to the incompatible metaphysical presuppositions underlying two competing presuppositional languages, such as scientific languages. This semantically sound, epistemologically well-established, and metaphysically profound interpretation not only affirms the tenability of the notion of incommensurability and confirms the reality of the phenomenon of incommensurability, but also makes some significant contributions to the discussion of many related issues, such as the notion of conceptual schemes, the notion of truth-value status and truth-value conditions, and the issue of cross-language understanding and communication.

According to the accepted translation-failure interpretation, the problem of incommensurability involves the nature of the meaning-referential relation between scientific languages. The incommensurability thesis is that some competing scientific languages are mutually untranslatable due to the radical variance of meaning or/and reference of the terms they employ. I argue that this interpretation faces many difficulties and cannot give us a tenable, coherent, and integrated notion of incommensurability. It has to be rejected. ;On the basis of two case studies, I find that the confrontations between many classical incommensurable languages are not confrontations between two untranslatable languages with different distribution of truth values, but rather the confrontations between incompatible fundamental presuppositions at the ontological level. We can always identify a truth-value gap between two incommensurable languages. Such a truth-value gap indicates a communication breakdown between the two language communities on the one hand, and is caused by the incompatible fundamental presuppositions underlying them on the other. ;I thereby identify the truth-value functional relationship between sentences, instead of the meaning-referential relationship between terms, as the dominant semantic relation between two incommensurable languages. According to my presuppositional interpretation of incommensurability, the real secret of incommensurability lies in the ontological setup of two competing presuppositional languages. When two presuppositional languages with incompatible factual commitments encounter with each other, the confrontation leads to a truth-value gap, and consequently a communication breakdown between them. Formally put, two scientific languages are incommensurable when core sentences of one language, which have truth values when considered within its own context, lack truth values when considered within the context of the other due to an ontological gap between them. ;The presuppositional interpretation makes many significant contributions to the discussion of the issue of incommensurability and the related metaphysical and epistemological issues: It confirms the existence of the phenomenon of incommensurability and makes it metaphysically and epistemologically significant. It establishes the tenability and integrity of the notion of incommensurability. It avoids many alleged unattractive epistemological and metaphysical consequences of the translation-failure interpretation.

What is the ontological status of facts? Are facts linguistic or extra-linguistic entities? If facts are extra-linguistic entities, are they mind-independent or relative to languages, theories or conceptual schemes? Based on a minimal definition of facts, the author argues that what are specified by true statements are not identical to true propositions expressed, so facts are not linguistic entities. Furthermore, what are specified by true statements are not to which a true statement corresponds, so facts are not mind-independent, either as concrete entities in the universe or as abstract entities in the world as it is. Last, the author presents an internal factual realist answer: although facts are neither in the world as it is, nor in a language, facts are real and exist in a world under consideration. A fact, as a non-linguistic correlate of a true statement of a language, exists in a world specified by the language.