| Quote #4
And then Caspian showed up in his true colours as a brutal tyrant and said out loud for everyone to hear that anyone found "stealing" water in future would "get two dozen." I didn't know what this meant till Edmund explained to me. It comes in the sort of books those Pevensie kids read. (5.13)
Eustace recognizes that his cousins have knowledge that he doesn't, but he reacts by looking down on them and disdaining the kind of reading they do.
| Quote #5
What awaited them on this island was going to concern Eustace more than anyone else, but it cannot be told in his words because after September 11 he forgot about keeping his diary for a long time. (5.20)
Eustace doesn't need to maintain control of his narrative once he becomes his own hero. If you're the protagonist, you don't need to be the narrator, too (although it's certainly possible).
| Quote #6
Edmund or Lucy or you would have recognised it at once, but Eustace had read none of the right books. (6.6)
Strangely the books that have educated Edmund and Lucy for their experiences in Narnia are fantasy stories – usually the last texts anyone would accuse of teaching valuable lessons!