CRACS Seminar: On the Structure of Natural Deduction Derivations for "Generally"

17 February 2017

Speaker: Leonardo B. Vana

Institution: Universidade Federal Fluminense (UFF), Brazil


We examine the structure of natural deduction derivations for some versions of ‘generally’ represented by generalized quantifiers. Versions of ‘generally’ (e. g. ‘most’, ‘many’, ‘several’) appear often in ordinary language and in some branches of science. To handle assertions with such vague notions, First-Order Logic is extended to logics for ‘generally’, which can be formulated as natural deduction systems with some special rules. These natural deduction systems for ‘generally’ share some macroscopic properties with First-Order Logic, but may differ with respect to some microscopic properties. We introduce some special systems and analyze the inner structure of their natural deduction derivations.


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