A well-known scientist (some say it was Bertrand Russell) once gave a public lecture on astronomy he described how the earth orbits around the sun and how the sun in turn orbits around the center of a vast collection of stars called our galaxy At the end of the lecture a little old lady at the back of the room got up and said What you have told us is rubbish The world is really a flat plate supported on the back of a giant totroise The scientist gave a superior smile before replying What is the tortoise standing on You re a very clever young man very clever said the old lady But it s turtles all the way down! - Taken from A Brief History of Time From The Big Bang to Black Holes by Stephen W Hawking