Wed Nov 16, 2005
234 Moses, 6–8 PM
|Working Group in the History and Philosophy of Logic, Mathematics, and Science
Marc Pauly (Stanford)
Logic, Metamathematics, and the Theory of Social Choice
Axiomatic characterization results in social choice theory are usually compared either regarding the normative plausibility or regarding the logical strength of the axioms involved. Here, instead, we propose to compare axiomatizations according to the language used for expressing the axioms. In order to carry out such a comparison, we suggest a formalist approach to axiomatization results which uses a restricted formal logical language to express the axioms involved. Axiomatic characterization results in social choice theory then turn into definability results of formal logic. The advantages of this approach include the possibility of non-axiomatizability results, a distinction between absolute and relative axiomatizations, and the possibility to ask how rich a language needs to be in order to express certain axioms.