A Case for Extensional Non-Wellfounded Metamodeling

Abstract

We introduce a notion of extensional metamodeling that can be used to extend knowl- edge representation languages, and show that this feature does not increase computational complexity of reasoning in many cases. We sketch the relation of our notion to various existing logics with metamodeling and to non-wellfounded sets, and discuss applications. We also comment on the usability of black-box reductions to develop reasoning algorithms for metamodeling.