Why does the Biography of Qu Yuan use the Book of Changes?

As we all know, Qu Yuan is the first great patriotic poet in the history of China, the founder of China's romantic literature, the founder and representative author of Songs of the South, and created the tradition of "vanilla beauty", known as "the ancestor of China's poetry" and "the ancestor of Ci". But what everyone doesn't know is that he also has the ability to predict in the Book of Changes. Lisao was written in Miluo, which predicted the development direction of Chu State.

Why is Miluo used for divination? Please see the analysis below.