It’s nice when people fall asleep on the train. When they hold still it makes it a bit easier to capture a sketch. This guy fell asleep with his mouth open. It was not pretty, but it occured to me he might not be sleeping at all but simply incubating some ideas. If nothing else, I can imagine he was. Sleep is a great time to solve problems. Go to sleep with something on your mind, a question, and inevitably you wake up with an answer. Try it.