The idea is simple. Within these algorithms, notes are treated like the DNA of music. It all starts with an initial population of ‘songs’– each a random jumble of notes stitched together. Over many generations, the algorithm breeds from the songs, finding and rewarding ‘beautiful’ features within the music to breed ‘better’ and ‘better’ compositions as time goes on. I say ‘beautiful’ and ‘better’, but – of course – as we already know, there’s no way to decide what either of those words mean definitively. The algorithm can create poems and paintings as well as music, but – still – all it has to go on is a measure of similarity to whatever has gone before.