 Supervaluationists have responded by noting that though the T-schema is not true, a corresponding mutual entailment thesis is not threatened: “‘p’ is true” entails and is entailed by ‘p’. However, the latter claim is strictly weaker than the corresponding claim involving the conditional according to supervaluationism, and one may wonder whether the weaker commitment is sufficient to capture what matters about truth (see Keefe 2000: ch. 8). Others have taken issue with the Williamson argument by pointing out that in the context of nonbivalent approaches to vagueness, negation can be variously defined and that the argument supposes a rejection of bivalence invoking a particularly strong reading of negation. In response Williamson contends that while an appropriately weak account of negation can be offered sufficient to undermine the argument for a general acceptance of bivalence, in the special case of vagueness the phenomenon of higher-order vagueness provides the materials for similarly reducing this weaker rejection to absurdity. (See Williamson 1994a: 193f. and Pelletier &amp; Stainton 2003 for further discussion.)