Chapter 2, “The Scholastic Traditions” Part 2 “How Man Truly Knows: Theories of Knowledge from Augustine to Ockham” pp. 42-62
Ozment details the different ways Augustine, Aquinas, and Ockham viewed knowledge. Augustine was initially strongly influenced by the Manichaean philosophy, which Ozment discusses on pp. 43ff. Beginning on p. 45 Ozment addresses Augustine’s Platonist influence. From these two categories of thought, Augustine had a view of sharp moral categorical distinctions and a view of true knowledge being that of the eternal. To know, then, is to know the Christ who dwells within us.
Aquinas, influenced more strongly by Aristotle, viewed knowledge differently (Ozment 1980, 47ff). Knowledge comes from the observable world rather than from interior illumination. Aquinas, then, reasoned from measurable evidence rather than from any internal impression.
William of Ockham, discussed p. 55ff, pursued a spare form of explanation. What is observed is not a universal unless it is absolutely logically necessary. Simpler is better.