 The idea of Mortimer J. Adler was that the "Propædia" and the "Micropædia" could serve the role of an index.More generally, Dr. Adler felt that the "Britannica" should not merely serve as a reference work, but also aspire to be a categorization of "omne scibile" (everything knowable), to fulfill Francis Bacon's grand conception of epistemology.Thus, the "Propædia" was intended to be the road-map of all knowledge, within which every fact, technique, and theory could be organized.