Allegory: The Theory of a Symbolic Mode
Who would think? Not a snappy title about what sounds like a pretty dull topic, yet this book, which I read back in the 1980s was a goldmine. Allegory is more than a literary device, but the way we perceive things, as Paul de Man argues, far more densely, in Blindness and Insight. I remember this book as being exciting, which either means I'm a nerd, or it was one hell of a good book on theory.