The rise of generic distinctions has lately reached a climax of absurdity, such that we can name off the top of our heads: house, witch house, dub, dubstep, hardstep, dancehall, dance-floor, punk, post-punk, noise, “Noise,” new wave, nu wave, No Wave, emo, post-emo, hip-hop, conscious hip-hop, alternative hip- hop, jazz hip-hop, hardcore hip-hop, nerd-core hip-hop, Christian hip-hop, crunk, crunkcore, metal, doom metal, black metal, speed metal, thrash metal, death metal, Christian death metal, and, of course, shoe-gazing, among others. (Meanwhile, 1,000 years of European art music is filed under “classical.”) Some people listen to some of these; others, to only one; and others still, to nearly all. And this accomplishes a lot of handy social sorting, especially among the young, whenever music is talked about or played so that more than one person can hear it.