Superassertibility and the Equivalence Schema: A Dilemma for Wright’s Antirealist

Abstract

Crispin Wright champions the notion of superassertibility as providing a truth predicate that is congenial to antirealists in many debates in that it satisfies relevant platitudes concerning truth and does so in a very minimal way. He motivates such a claim by arguing that superassertibility can satisfy the equivalence schema: it is superassertible that P if and only if P. I argue that Wright’s attempted proof that superassertibility can satisfy this schema is unsuccessful, because it requires a premise that has not been properly motivated and is prima facie implausible. I further argue that, even if the dubious premise is accepted, the resulting proof is intuitionistically invalid. This is problematic, because a proponent of superassertibility as a truth predicate has independent reasons to affect a logical revision in the direction of intuitionism. The resulting dilemma suggests that superassertibility may not be an adequate truth candidate for any significant ranges of discourse.