lesson from and for Achilles, book 9

In this book, Agamemnon finally relents, and sends Odysseus to Achilles with offers of vast gifts in exchange for his return to battle. In a long speech, Achilles refuses. From his point of view, what lesson should be learned from his argument with Agamemnon? Subsequently, his father-figure and nurse Phoenix delivers a speech, in which he explains to Achilles what he should learn from this conflict. From his point of view, what lesson should be learned?

Write a paragraph that addresses these lessons in book nine. Post your reply here.