In a church in Halberstadt, Germany, an organ is playing a John Cage piece called Organ²/ASLSP, for “as slow as possible”. The performance began on 5 September 2001 with a rest, and the rest lasted seventeen months; the first sound came in February 2003. The chord changed for the seventeenth time on 5 August 2026, when more than 150 people came to hear one more pipe join in. The next change is on 5 October 2027. The last note is due on 4 September 2640.

You can already buy a ticket for the ending. It costs 2,640 euros and it is inheritable, which makes it less a ticket than a letter: something handed down through a family for six centuries with a note saying where to sit. Nobody who was there at the beginning will hear the end, and nobody at the end will have heard the beginning, though in fairness the beginning was silence. The piece only exists whole the way a cathedral does, or a family, as something carried by people who each get a little of it. The crowd that turned up in August was there for the same reason the one in 2640 will be. It was their turn.