Rules with exceptions
Modus ponens may not be truth-preserving, but it still seems valid in some other sense: we still want to infer a rule’s consequent from its antecedent as long as no exception is inferred
? In Reason-Based Logic, this is formally achieved using techniques that (at least) go back to Reiter’s extension definitions
I currently think that it is the mixture of Toulmin’s warrant and Dung’s admissibility (as it occurs in ArguMed 2.0) that replaces truth preservation as a criterion for the validity of rules of inference
? Toulmin, Dung, ArguMed 2.0, Formalism and interpretation in the logic of law