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] |
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] |