Three-Valued Plurivaluationism of Vague Predicates

Disagreeing with Williamson on vagueness, the author proposes a solution that he calls “three-valued plurivaluationism” to the age-old sorites paradox. In essence, it is a three-valued semantics for a first-order language with identity with the additional suggestion that a vague language has more than one correct interpretation. Unlike the traditional three-valued approach to a vague language, the so-called three-valued plurivaluationism, so the author argues, can accommodate the phenomenon of higher-order vagueness. And, unlike the tr`aditional three-valued approach to a vague language, the so-called three-valued purivaluationism, so the author argues, can also accommodate the phenomenon of penumbral connection when equipped with “suitable conditionals”. The author also shows that this three-valued purivaluationism is a natural consequence of a restricted form of Tolerance Principle (TR) and a few related ideas, and argues that (TR) is well-motivated by considerations of how we learn, teach, and use vague predicates.