|Proof Theory: mathematics, logic is about the existence or nonexistence of finite strings of symbols allowing to derive a statement. Therefore, proof theory is a part of the syntax, as opposed to the model theory, which belongs to the semantics. See also model theory, syntax, semantics.|
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|Proof Theory||ad HC I 119
Validity/Propositional Calculus: truth tables are not sufficient for an evaluation of formulas in the propositional calculus - because we cannot assign specific individual variable and predicate variables.
Geist und Welt Frankfurt 2001