The Purpose of Literature

In his introduction to the new anthology, Vital Signs: Essential AIDS Fiction (a very good collection, BTW), Dale Peck drops this line:

"It's important to remember that literature doesn't facilitate understanding but rather empathy, which is a very different proposition; and for some people the mere fact of a book's existence can effect extraordinary personal change."

I remember a lot of English teachers telling us that we read to learn and understand about other people and cultures, but Peck's assertion above seems to be more to the point.

Any thoughts?