He said that it was very difficult to become an astronaut. I said that I knew. You had to become an officer in the air force and you had to take lots of orders and be prepared to kill other human beings, and I couldn't take orders. Also I didn't have 20/20 vision which you needed to be a pilot. But I said that you could still want something that is very unlikely to happen.
Christopher Boone
The curious incident of the dog in the night-time, Mark Haddon