|Calculus: a calculus is a system of symbols for objects (which are not further specified) as well as rules for the formation of expressions by the composition of these symbols. There are other rules for transforming composite expressions into other expressions. As long as no specified objects are accepted for the individual symbols, the calculus is not interpreted, otherwise interpreted.|
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artificial language / formal language/ counterpart / Mates: the statements of the natural language correspond the artificial formulas, as a counterpart, not as abbreviations - if symbols are associated with no sense, then it is an uninterpreted calculus.
Propositional calculus /p.c.: has no quantifiers.
Elementare Logik Göttingen 1969