Some three years ago a young philosophy teacher living in Paris bought a cheap Japanese guitar. He knew a lot of Spinoza and no chords but before long he was explaining to the Director of the Ecole Normale Superieur that the strange songs he now found himself writing were undermining his tolerance for syllogisms – ‘All men must die so Socrates must die’ is irrefutable but ‘Round round I get around’ is inspirational; a rhythm, a creed, a water-tight system, a meaning of life.