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C.I.Lewis VsParadoxes of the implication: "strict implication": modal: instead of "from contradiction any statement": "from impossible ..." - WesselVsLewis, C.I.: circular: modal terms only from logical entailment relationship - 2.Vs: strict Implication cannot occur in provable formulas of propositional calculus as an operator.
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Paradoxes of implication: strategy: avoid contradiction as antecedent and tautology as consequent.
Paradoxes of implication/quantifier logic: Additional paradoxes: for individual variables x and y may no longer be used as any singular terms - otherwise from "all Earth's moons move around the earth" follows "Russell moves around the earth" - solution: Limiting the range: all individuals of the same area, for each subject must be clear: P (x) v ~ P (x) - that is, each predicate can be meant as a propositional function - Wessel: but that is all illogical.
Logik Berlin 1999