And there’s none more rigorous than Joe Carducci’s Rock and the Pop Narcotic. Carducci may be a bit of a reactionary, but his theory of rock is grounded in a precise, materialist definition of it as music, rather than ‘attitude’, ‘spirit’, ‘rebellion’, or any other metaphysical notions. Rock’s essence, says Carducci, is the real-time interaction of drums, bass and rhythm guitar. A group should be a rhythmic engine creating kinetic energy; ‘breathing’ as an organic entity.