Contents: The many facets of incommensurability; Incommensurability as untranslatability; Incommensurability and conceptual schemes; In defense of the very notion of conceptual schemes; Case studies: the emergence of truth-value gaps; Toward the presuppositional interpretation; Kuhn's taxonomic incommensurability: a reconstruction; A defense of the notion of semantic presupposition; The structure of a presuppositional language; Existential presumptions and universal principles; Categorical frameworks; The failure of cross-language understanding; Hermeneutic understanding in abnormal discourse; Informative communication breakdown: the transmission model; Dialogical communication breakdown I: Gadamer's conversation model; Dialogical communication breakdown II: Habermas's discourse model; The concept of incommensurability; Bibliography; Index.