Page 170, the Q&A for Lecture 5: About Peikoff's list of 20 key items, arranged hierarchically, a student asks: "If metaphysics comes first in the branches of philosophy, then why do the first ten items go back and forth between metaphysics and epistemology?" (The list is presented and discussed on pp. 150-166.) Peikoff says: "Because metaphysics does not come first. Metaphysics and epistemology are simultaneous -- what exists and how we know it are the foundation that starts together. ... The two are completely intertwined."