|Worn books are loved books.|
A better question would be, why do we need a canon anyway? I would argue that we do. A common literature gives us common references, a common education. But no one can agree on more than a few books because we all have such different ideas about what's good literature and what's important. The more I learn about literature outside of British and American writers, I realize how little the rest of the world is represented in the nebulous thing we call the canon.
It's a lot of fun to debate each other about what everyone should read, but I suspect that at true canon would be a really short list.
And Shakespeare would be on it.