Truth pluralism and many-valued logics: A reply to Beall

Abstract

Mixed inferences are a problem for truth pluralism, a doctrine which aims at combining truth assessability and anti-realism with respect to allegedly non-descriptive sentences, such as moral sentences. It seems that truth pluralists have to give up the classical account of validity. Against this, JG Beall suggests that truth pluralists can adopt the account of validity used in many-valued logics: validity can be defined as the conservation of designated values. The problem, I argue, is that there is ground to believe that on this account sentences which are true in one or other way also fall under a genenc truth predicate. I also argue that mixed conjunctions make for a further problem for truth pluralism, and more particularly for Beall's version of it. Finally, I consider the deeper worry that the distinction between truth which does and truth which does not entail realism is inferentially irrelevant. © The Editors of The Philosophical Quarterly, 2000.