Mathematical logic and algebra have always had a certain affinity and have been drawing closer in some ways in recent years. The research project of A. Blass deals with several problems at the interface between category theory, particularly topos theory, on the one hand, and logic, particularly set theory and combinatorics, on the other hand. The problems lie in three general areas: (1) logical aspects of geometric morphisms and classifying topoi, (2) set theory in topoi, and (3) applications of the category-theoretic perspective to concepts in set theory and combinatorics.
