'Nothing, in the sense you wish to convey. Everything, in another sense. You can attach any ideas you please to music, but music, if you will forgive me saying so, rejects them all equally. Art has to do with emotions, not with ideas, and the great defect of literature is that it can only express emotions by means of ideas. What makes music the greatest of all the arts is that it can express emotions without ideas. Literature can appeal to the soul only through the mind. Music goes direct. Its language is a language which the soul alone understands, but which the soul can never translate. Therefore all I can say of the Fantasia is that it moves me profoundly. I _know how_ it moves me, but I cannot tell you; I cannot even tell myself.' Vistas of comprehension opened out before me. 'Oh, do go on,' I entreated him. 'Tell me more about music. Do you not think Chopin the greatest composer that ever lived? You must do, since you always play him.' He smiled. 'No,' he said, 'I do not. For me there is no supremacy in art. When fifty artists have contrived to be supreme, supremacy becomes impossible. Take a little song by Grieg. It is perfect, it is supreme. No one could be greater than Grieg was great when he wrote that song. The whole last act of _The Twilight of the Gods_ is not greater than a little song of Grieg's.' 'I see,' I murmured humbly. '_The Twilight of the Gods_--that is Wagner, isn't it?' 'Yes. Don't you know your Wagner?' 'No. I--' 'You don't know _Tristan_?' He jumped up, excited. 'How could I know it?' I expostulated. 'I have never seen any opera. I know the marches from _Tannhäuser_ and _Lohengrin_, and "O Star of Eve!"' 'But it is impossible that you don't know _Tristan_!' he exclaimed. 'The second act of _Tristan_ is the greatest piece of love-music--No, it isn't.' He laughed. 'I must not contradict myself. But it is marvellous--marvellous! You know the story?' 'Yes,' I said. 'Play me some of it.' 'I will play the Prelude,' he answered. I gulped down the remaining drops in my glass and crossed the room to a chair where I could see his face. And he played the Prelude to the most passionately voluptuous opera ever written. It was my first real introduction to Wagner, my first glimpse of that enchanted field. I was ravished, rapt away. 'Wagner was a great artist in spite of himself,' said Diaz, when he had finished. 'He assigned definite and precise ideas to all those melodies. Nothing could be more futile. I shall not label them for you. But perhaps you can guess the love-motive for yourself.' 'Yes, I can,' I said positively. 'It is this.' I tried to hum the theme, but my voice refused obedience. So I came to the piano, and played the theme high up in the treble, while Diaz was still sitting on the piano-stool. I trembled even to touch the piano in his presence; but I did it. 'You have guessed right,' he said; and then he asked me in a casual tone: 'Do you ever play pianoforte duets?'