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Entailment/Wessel: = implication (not an operator, but a predicate) >paradoxes, because content can be contradictory, even if the form is valid - Conditional: (e.g. scientific statement) would be false for the same reason (because the content does not form a context)
Logical Entailment/Wessel: statement about the context (of two statements), not about two objects - in the rules of entailments no semantic terms must occur - tA: "the statement A" (term or name) -
Entailment/Sense/Wessel: If A I- B, then not only with regard to the truth value, but also in terms of sense - but not merely assertion that "linked by sense" - context guaranteed by occurrence of the same variables or the "same material of terms and statements.
Use/Mention: logical entailment: A I- B: talks about statements (i.e. precisely not content) - Conditional: A -> B: talks about content and about what is being talked about in the statements (e.g. current, magnetic field) - Question/(s): mention = if statements are not talked about in terms of content? - Use = if e.g. the truth is found out? - But: "A is true" - precisely does not mean "the current flows".
Conditional/Wessel (s): empirical if-then, no logical necessity conditional operator I- not truth-functional.
Conditional/Wessel: e.g. from empirical studies, from statements about entailment, from axioms, from definitions, from other statements according to rules of inference.
Conclusions on the conditional cannot be made from a conjunction (empirical) - E.g. Potsdam >100,000 inhabitants and state capital, i.e. if P >.... false.
Conditional/Wessel: subjunction follows from conditional statement - ((s) but not vice versa.)
Existence Load/Wessel: cannot be determined like this in conditionals, because not truth-functional.
Logik Berlin 1999