What could this sign possible mean? A reminder to vertigo sufferers of which way is up? A public service campaign in a country of pessimists to “look up at the sky, hold your head high?” The unexpectedness combined with the curiosity it generates in the observer resulted in the powerful ability of this visual to control my reaction and look up at the empty sky. I couldn’t help it. Was the purpose of this visual control to make me look up? It’s unknown and ambiguous. Few visual controls are as effective, or as useless.