C.S. Lewis’s An Experiment In Criticism. 
It is one of those books you read and re-read! I've read mine twice now and it remains one of the best things I have ever read, about reading.
Typical of Lewis's deeper insight into things, his "Experiment" consists in a reversal of the usual method of literary judgment. Instead of classifying books, he classifies readers and how they "use" or "receive" books.
The true (unbiased) critic does not pontificate a judgment of 'good' or 'bad' upon a book without careful consideration of the possible confusion between degrees of merit and differences of kind.
"I want to convince people," says Lewis, "that adverse judgments are always the most hazardous... A negative proposition is harder to establish than a positive. One glance may enable us to say there is a spider in the room; we should need a spring-cleaning (at least) before we could say with certainty that there wasn't. When we pronounce a book good we have a positive experience of our own to go upon... In calling the book bad we are claiming not that it can elicit bad reading, but that it can't elicit good. This negative proposition can never be certain."
Central to his argument is the fact that the same book may be read in different ways.
It follows then that there is a certain speculative nature to evaluative criticism, and therefore no amount of reliance upon literary criticism can absolve one from the responsibility of becoming a GOOD READER© .
And what is a good reader?
Well, that is the question isn't it?
In my opinion, I feel that Lewis's "Experiment" can answer that question more effectively than anything I've ever come across. I would encourage you to read it, and see where you fit into his categories of the "literary" and the "unliterary" person (too lengthy to enumerate here). If at any point, you feel offended and want to hurl the book across the room... you are probably of the latter category.
Lewis deplored the technical dissection of what he loved so dearly... the simple act of reading.
I loved his image in chapter 2 of the "status seeker" type of readers, gathered to discuss the finer (and, of course hidden) points of "approved literature" while the only real literary experience in such a scenario "may be occurring in a back bedroom where a small boy is reading Treasure Island under the bed-clothes by the light of an electric torch."
Lewis sought in books (as he called it here) an "enlargement of his being".
He says on page 52, "I am probably one of many who, on a wakeful night, entertain themselves with invented landscapes. I trace great rivers from where the gulls scream at the estuary, through the windings of ever narrower and more precipitous gorges, up to the barely audible tinkling of their source in a fold of the moors. But I am not there myself as explorer or even as tourist. I am looking at that world from outside."
This is a terrific/significant book that will be read, re-read, and cherished by anyone who has ever had similar musings.
Oh, and by the way... all GOOD readers have!