One winter shortly before the Six Weeks War my tomcat, Petronius the Arbiter, and I lived in an old farmhouse in Connecticut... the place had eleven doors to the outside. Twelve, if you counted Pete's door. I always tried to arrange a door of his own for Pete- in this case a board fitted into a window in an unused bedroom and in which I had cut a cat strainer just wide enough for Pete's whiskers. I have spent too much of my life opening doors for cats- I once calculated that, since the dawn of civilization, nine hundred and seventy eight man-centuries have been used up that way. I could show you figures.
the door into summer, Robert A. Heinlein