Augustine considers his second error in particular to be "amazing madness." The soul, he now knows, is not itself the fundamental truth or good. It participates in God, but is not itself God or some small piece of God. The error about evil and this error about the soul together constitute, in Augustine's eyes, a massive arrogance characteristic of Manichee beliefs: evil is thought to exist due to God's impotence (rather than human impotence), and humans mistake themselves for God.
With this retraction made, Augustine moves from what he was writing at the time to what he was reading: Aristotle's Categories. Like the Neoplatonists, Augustine now understands Aristotle's work as a system applicable only to this world (and to logical exercises in general), but not to God. At the time, however, he was puzzled and misled. Trying to conceive how God could have beauty and magnitude as attributes (following Aristotle's system), he failed to realize that "you [God] yourself are your own magnitude and your own beauty."
This error led Augustine further into the false problems of trying to imagine God. With the influence of Manichee beliefs all around him, he pictured God as "like a luminous body of immense size and myself a bit of that body. What extraordinary perversity!"