2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/75878In this paper, we identify some categorical structures in which one can model predicative formal systems: in other words, predicative analogues of the notion of a topos, with the aim of using sheaf models to interprete predicative formal systems. Among our technical results, we prove that all the notions of a ``predicative topos'' that we consider, are stable under presheaves, while most are stable under sheaves.LogicCategory Theory03F50;18A15 (Primary) 03C90;03G30;18C50;18F20 (Secondary)text