A few years ago, during the conflagrative, diluvial climax of a performance of the Ring Cycle in Covent Garden, my finger ventured north, on a discreet reconnaissance Mission, into a nostril. Duly it alighted upon, and opportunistically hacked out, a deeply entrenched bogey. This intervention unleashed a tide of blood, which I struggled desperately to staunch in the few remaining moments before lights on. Never have those final bars, so soaring and expansive, been more precious to me. Here was an example of TS Eliot’s ‘objective correlative’, ‘a set of objects, a situation, a chain of events… external facts’ through which art achieves emotional expression. My body itself, oozing liquid fire, had been momentarily invested, consummated, by Wagner’s masterpiece, a rogue cameo in the ultimate music-drama.