Fitch's Paradox and Probabilistic Antirealism

Fitch’s paradox shows, from fairly innocent-looking assumptions, that if there are any unknown truths, then there are unknowable truths. This is generally thought to deliver a blow to antirealist positions that imply that all truths are knowable. The present paper argues that a probabilistic version of antirealism escapes Fitch’s result while still offering all that antirealists should care for. 1. Antirealism and Fitch’s Paradox. Define antirealism as the thesis that truth is epistemically constrained. While this can be cashed out in various ways, it is commonly taken to imply at least that all truths are knowable, that is,