 As well as treating the Pragmatic Maxim as part of a constructive account of the norms that govern inquiry, Peirce, like James, gave it a negative role as a tool for demonstrating the emptiness of a priori metaphysics. In section 3.1 we shall see how pragmatic clarification of reality may be used to undermine a flawed ‘nominalistic’ conception of reality that led to the ‘copy theory of truth’, problematic Cartesian certainty-seeking strategies in epistemology, and Kant’s concept of a ‘thing in itself’. A more vivid non-logical example of using the maxim to undermine spurious metaphysical ideas was Peirce’s early argument that the Catholic understanding of transubstantiation was empty and incoherent. Since all we mean by wine is something that has certain distinctive effects upon the senses, ‘to talk of something as having all the sensible characters of wine, yet being in reality blood, is senseless jargon’ (EP1: 131f). It is important to note, however, that the maxim is in the end only a tool for clarifying meaning; not Peirce’s theory of meaning proper. This is to be found in his theory of signs or semiotic, which is discussed below (4.4). 