I tend to think that the average fiction book is less interesting that the average non-fiction book, but that the best fiction books are much, much better than the best non-fiction ones (and teach you more, and deeper things).

This one is up there with the very best. It is exquisitely well written (John Williams was a literature professor, directing a creative writing program), and despite the plainness of the plot(or maybe because of it?) it offers a remarkable view of what gives meaning to life (IMHO of course. Your millage may vary).