  Category theory has become central to certain aspects of theoretical physics.
Bain [Synthese, 190:1621--1635 (2013)] has recently argued that this has
significance for ontic structural realism. We argue against this claim. In so
doing, we uncover two pervasive forms of category-theoretic generalization. We
call these `generalization by duality' and `generalization by categorifying
physical processes'. We describe in detail how these arise, and explain their
significance using detailed examples. We show that their significance is
two-fold: the articulation of high-level physical concepts, and the generation
of new models.
