B - Philosophy (General)
B1-99: General
B108-708: Ancient
B720-765: Medieval
B770-785: Renaissance
B790-5802: Modern
BC - Logic
BD - Speculative Philosophy
BD10-41: General
BD95-131: Metaphysics
BD143-237: Epistemology
BD240-260: Method
BD300-450: Ontology
BD493-701: Cosmology
BH - Aesthetics
BJ - Ethics