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logical operators / Wessel: e.g. and, not, or, all, some, "the fact that", "the non-fact that" ..- Termini / Terms / Wessel: e.g "the fact that metals conduct electricity ’"H2O", "brother and sister", "divisible by three" ... - no terms are: and, all, in, or, "the earth revolves around the sun".
Operator / Wessel: must not occur more than once in provable formulas of propositional logic -
(Operator / (s): (e.g. subjunction) does not lead to paradoxes, because it is not "predicated of something" like predicates (implication) - ((s) Operator / (s): rather purely formal - in contrast: predicate: content).
Logik Berlin 1999