Steven Berlin Johnson contemplates the structure of books:

[T]he real question--a question I don't have the answer to--is what happens in our minds when we enjoy something like a book or song, without being fully aware of what makes it enjoyable. On some level, there is something like an unconscious processing of the information, but it's not an unconscious that looks anything like the Freudian version.

Our brains unconsciously process external information all the time, of course, but usually these are hard-wired skills, more nature than nurture. But a chord progression or a chapter from a non-fiction book are pure works of culture; our brains didn't evolve dedicated resources designed to appreciate their subtle arts. Yet somehow we appreciate those deep structures, even as they fly beneath the radar of our consciousness.

The funny thing is that people will reliably perceive that deep structure in one context: when we get it wrong. Mangle the chords in a popular song and the background will suddenly become foreground.

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