After the great affirmation of Thus Spake Sarathustra (1883-5), Nietzsche produced a devastating diagnosis of the worthlessness of contemporary existence. In Beyond Good and Evil (1886) Nietzsche returned to a favourite theme: how cultures lose their creative drive and become decadent. He offers a wealth of fresh insights into the self-destructive urge of Christianity, the prevalence of 'slave moralities' and the terrible (and now very obvious) dangers in the headlong pursuit of philosophical or scientific truth. And yet, as always in Nietzsche, his savage criticisms are only a prelude to a more optimistic vision. While his complete commitment to what is 'life-advancing' may not convince everyone, Beyond Good and Evil still possesses an uncanny power to unsettle almost all of our received opinions.