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- Theodore J. Everett (2000). A Simple Logic for Comparisons and Vagueness. Synthese 123 (2):263-278.I provide an intuitive, semantic account of a new logic forcomparisons (CL), in which atomic statements are assigned both aclassical truth-value and a ``how much'''' value or extension in the range [0, 1]. The truth-value of each comparison is determinedby the extensions of its component sentences; the truth-value ofeach atomic depends on whether its extension matches a separatestandard for its predicate; everything else is computed classically. CL is less radical than Casari''s comparative logics, in that it does not allow for the formation of comparative statements out of truth-functional molecules. I argue that CL provides a betteranalysis of comparisons and predicate vagueness than classicallogic, fuzzy logic or supervaluation theory. CL provides a modelfor descriptions of the world in terms of comparisons only. Thesorites paradox can be solved by the elimination of atomic sentences.
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Propositional logic -- Propositions and arguments -- Connectives and argument forms -- Truth tables -- Trees -- Vagueness and bivalence -- Conditionality -- Natural deduction -- Predicate logic -- Predicates, names, and quantifiers -- Models for predicate logic -- Trees for predicate logic -- Identity and functions -- Definite descriptions -- Some things do not exist -- What is a predicate? -- What is logic?
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