"...... the answer has to do with the difference between difficulty and subtlety.... For one thing, difficulty is straightforward — you either figure out what's difficult, or you don't. You might fail, but you aren't going to be misled. (In this sense, and in its implicit endorsement of hard work, difficulty is a concept that has long been central to our shared identity as Americans). Subtlety is different, though. Subtlety wants to be missed by all but the chosen few; it is aloof, withholding and aristocratic — sometimes manipulative and always disguised. It has less to do with theory and technique, which can be learned mechanically, than with style and sensibility, which require intuition. It wants to be looked at but not seen. It's unnerving."

From a review of Elizabeth Bishop's Edgar Allan Poe and the Juke Box