Once, when I was thinking about renting a small office to write in, I looked at a space being vacated by another writer. The place was perfect — lots of light, and just big enough to stand up and stretch your legs every so often but not big enough for a comfortable sofa, which is a thing I find impossible to resist after lunch. I need to rent a place to work, I told myself. I’m already renting a place to sleep.

The place was empty except for a single index card, taped solidly to the wall at about the height where the writer’s desk was. On the index card, he had written this: