This paper argues that, given a certain apparently inevitable thesis about content, we could not know our own minds. The thesis is that the content of a thought is determined by its relational properties.

Self-consciousness constitutes an insurmountable obstacle to functionalism. Either the standard functional definitions of mental relations wrongly require the contents of self-consciousness to be propositions involving “realizations” rather than mental properties and relations themselves. Or else these definitions are circular. The only way to save functional definitions is to expunge the standard functionalist requirement that mental properties be second-order and to accept that they are first-order. But even the resulting “ideological” functionalism, which aims only at conceptual clarification, fails unless it incorporates (...) the thesis that the mental properties are fully “natural” universals. Accordingly, mental properties are sui generis: first-order, nonphysical, natural universals. (shrink)

Almost every contemporary theory of knowledge is a version of fallibilism, yet an adequate statement of fallibilism has not yet been provided. Standard definitions cannot account for fallibilistic knowledge of necessary truths. I consider and reject several attempts to resolve this difficulty before arguing that a belief is an instance of fallibilistic knowledge when it could have failed to be knowledge. This is a fully general account of fallibilism that applies to knowledge of necessary truths. Moreover, it reveals, not only (...) the connection between fallibility and error, but the connection between fallibility and accidental truth as well. (shrink)