The curtain rises. It is a sultry summer night; the black woods stand round a garden; on the left is the castle of Mark, with a torch blazing at the doorway, making the surrounding night blacker. Sounds of hunting-horns are dying away in the distance. Brangaena and Isolda are there listening, and Brangaena, to music of enchanting beauty, is warning Isolda that the hunters can be no great way off. "Listen to the brook," says Isolda. "How could I hear that if the horns were near?" Then comes one of Wagner's matchless bits of painting—the brook rippling through the silent night. Isolda is now going to extinguish the torch, as a signal to Tristan that he may approach. Brangaena protests, and warns Isolda against Melot, who has arranged this night hunt as a trap to catch Tristan; and she bewails the officiousness which led her to substitute the love-philtre for the poison. The rest of the scene may be passed over. The music is woven out of themes just quoted, and another which will play a big part in the love-duet:
Of course, Isolda prevails. Brangaena is sent to keep watch, and Isolda throws down the torch to the Death motive. Tristan rushes in, and the most passionate love-duet ever written begins.
After the first ecstasies have subsided the lovers converse. They must talk about something—what should it be? As Wagner's thoughts were occupied with Schopenhauer at the time, he makes them talk a sort of pseudo-Schopenhauer. Light is their enemy; only in night—extinction—can perfect joy be found. It was the deceitful phantoms of daylight—worldly ambitions—that betrayed Tristan into acting so basely towards Isolda (before the drama opens); it was the light of the torch that kept him so long from her this night; and now in the darkness they find rapturous peace. This is the substance of what is said. Twice Brangaena warns them that the dawn is at hand, but they do not heed her. Her songs are exquisite enough, surely, but the lovers, steeped in their bliss, have no ears for them. Their own music is far more beautiful:
And again:
The lovers are presently awakened. At the very climax of a mad, tumultuous passage Brangaena gives a scream; Kurvenal rushes in, and then—enter Mark, Melot and the other hunters. Melot's trap has worked satisfactorily.
The cold red dawn slowly breaks. The phantoms of the daylight have broken in upon the dream of night, which alone is true. It is here that many would have the act terminate. Such an ending would leave the idea of the act half expressed, and shatter the noble architectonical scheme of the whole drama. The idea of the act—that the light is the lovers' enemy, the dark their friend and refuge—has to be worked out to prepare for the last act; the idea of the drama—that the lovers must be seen gradually thrust away from life (which is light) to death (which is eternal night)—must be carried one step further. Mark, in an agony of grief, asks them why they, the two he loves best in the world, dishonour him in so frightful a fashion. He presses home to them their sin and his suffering, his affection and their indifference to it; and he ends up with the question, "Why?" Tristan cannot answer; he perceives only that Mark's love is a more terrible menace for them than any trap laid by Melot. Without their passion they cannot live, and it is not Melot and the general outside world that threaten to sunder them, but their protector and dearest friend. The passion is irresistible, and Tristan faces the inevitable. He asks Isolda if she will follow him where he is now going: she replies that she will; and he, after taunting Melot with his treachery, lets him thrust him through with his sword. The drama has moved a stage further on, and there remains now only the logical completion. Anyone who thinks all this is to read into the opera a meaning that is not there merely accuses me of being greater than Wagner; without this we have only a commonplace Divorce Court episode.