more from this thinker | more from this text
Full Idea
It is an illusion that many-valued logic constitutes a well-motivated and rigorously worked out theory of vagueness. ...[top] There has been a reluctance to acknowledge higher-order vagueness, or to abandon classical logic in the meta-language.
Gist of Idea
Many-valued logics don't solve vagueness; its presence at the meta-level is ignored
Source
Timothy Williamson (Vagueness [1994], 4.12)
Book Ref
Williamson,Timothy: 'Vagueness' [Routledge 1996], p.130
Related Idea
Idea 21596 Vagueness undermines the stable references needed by logic [Williamson]
| 8942 | Lukasiewicz's L3 logic has three truth-values, T, F and I (for 'indeterminate') [Lukasiewicz, by Fisher] |
| 14263 | Strong Kleene disjunction just needs one true disjunct; Weak needs the other to have some value [Fine,K] |
| 21602 | Many-valued logics don't solve vagueness; its presence at the meta-level is ignored [Williamson] |
| 18787 | Three-valued logic is useful for a theory of presupposition [Mares] |
| 8943 | Three-valued logic says excluded middle and non-contradition are not tautologies [Fisher] |
| 16335 | In Strong Kleene logic a disjunction just needs one disjunct to be true [Halbach] |
| 16334 | In Weak Kleene logic there are 'gaps', neither true nor false if one component lacks a truth value [Halbach] |