But he also studied carefully Kant's Critique of Pure Reason during a course taught by Bruno Bauch, and was one of very few students to attend Gottlob Frege's courses in mathematical logic.
Pero tamén estudou coidadosamente a Crítica da razón pura de Kant nun curso impartido por Bruno Bauch, e foi un dos escasos estudantes que acudiu aos cursos de Frege sobre lóxica matemática.