From Darkness, Light:
Regardless of whether Emily Howell's work is to your taste, it is compelling evidence that Cope is at least partially right about how composing works. While it's not difficult to guess Howell's influences, the fact that they sound like original, creative pieces is a testament to the database model of composing. Still, I suspect most people will find Cope's theory of composing inherently distasteful. We prefer to think of art as an art, not a science. Not only does Cope disagree, he is an extreme relativist about music. In his opinion, all melodies—any rhythmic string of notes—are equally good. The reason we like some better than others is a product of how we've been socialized in a Western musical tradition. The work that Emmy and Emily Howell produce tends to sound pretty Western, but that's the sort of material they were given to work with.
To stump Cope, I presented him with the famous melody to the second movement of Beethoven's C minor Sonata, the "Pathétique." Could a computer really generate such a beautiful string of notes? Surely this was the product of Beethoven's genius. Cope directed me to Mozart's Piano Sonata 14, also in C minor. A nearly identical melody, in the same key, occurs three minutes into the second movement. Of course, pointing out that Beethoven ripped off Mozart doesn't explain where Mozart got the melody. But Cope makes a convincing case that Mozart, in turn, may well have heard something like it and stored it away. In other words, great melodies (to our Western ears) are products of evolution, not creationism. Even if Mozart never heard the precise melody, he surely heard similar riffs that his mind, which was constantly recombining bits and pieces of his database, stuck together to make the final product. Cope has another program, called Sorcerer, that can scan a piece, compare it to various databases, and look for similar passages in earlier works. Positive matches appear more often than you'd like.
I don't expect Emily Howell to ever replace the best human composers. But as a recent Miller-McCune profile of Cope notes, the field of "artificial creativity," an offshoot of AI research, is only just getting on its feet. (Other "AC" researchers are working on programs to paint pictures, write jokes, and tell stories.) Yet even at this early moment in AC research, Emily Howell is already a better composer than 99 percent of the population. Whether she or any other computer can bridge that last 1 percent, making complete works with lasting significance to music, is anyone's guess.
Correction, May 20, 2010: Aaron Copland's name was originally misspelled as "Copeland." (Return to the corrected sentence.)
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