Thomas Kuhn’s Incommensurability and Relativism

One of the central notions in Thomas Kuhn’s thought is the notion of incommensurability. Generally, we can distinguish two kinds of incommensurability: methodological and semantic incommensurability. The methodological incommensurability is the thesis that the standards of theory appraisal are themselves theory-dependent. So, some kind of standard variance can be recognized at the level of theory appraisal. On the other hand, semantic incommensurability seems to imply semantic variation between theories or paradigms, regarding the terms occurring in them. These two kinds of dependencies have been employed in support of two forms of relativism: truth relativism and epistemic relativism. The main focus of this paper is on the possible relations that one can depict between incommensurability and these two kinds of relativism. First, I outline possible connections articulated by sufficient and necessary conditions. After that, I attempt to assess the viability of the resulting propositions.