|Conservativity, philosophy, logic: Conservativity is the demand not to introduce a new vocabulary, or to examine, when introducing new vocabulary, which conclusions are legitimate. Firstly, new expressions may occur in premisses, but not in true conclusions. See also introduction, introduction rules, extensions, translation.|
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Conservativity/Extension/Language/Tonk/Brandom: pro conservative extension: if the rules are not inferentially conservative, they allow new material inferences and can change the contents that were associated with the old vocabulary - expressive logic/Brandom: requires that no new inferences that contain only old vocabulary are rendered appropriate (if they have not been previously).
E.g. "boche"/Dummett: non-conservative extension: statements that do contain the expression (!) could be inferred from others that do not contain the expression either - E.g. conclusion from German nationality to cruelty - BrandomVsDummett: this is not about non-conservativity: it only shows that the expression "boche" has a content which is not contained in the other expressions - e.g. the term "temperature" has also changed with the methods of measurement - it s not about the novelty of a concept, but about unwanted conclusions.
Especially the material content of concepts is lost when the conceptual content is identified with the truth-conditions.
Expressive Vernunft Frankfurt 2000
Begründen und Begreifen Frankfurt 2001