There is an old story about a worker who keeps bringing a rock to a supervisor. Each time, the supervisor looks at it, shakes his head, and says, “Bring me another rock.” Back the worker goes. No explanation of what the right rock would be. …

“That was a great meeting! Finally we’re going to make our exhibitions sustainable.” “I agree! It’s about time we considered whether we can pay for these things.” “What? I thought the boss was talking about the environment.” …