[caption id="" align="aligncenter" width="560" caption="Dilbert Feb 7th 2011"][/caption]
Wikipedia says:
The most widely known version appears in Stephen Hawking's 1988 book A Brief History of Time, which starts: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 tortoise." The scientist gave a superior smile before replying, "What is the tortoise standing on?" "You're very clever, young man, very clever", said the old lady. "But it's turtles all the way down!"[1]
The origins of the turtle story are uncertain.
The quote makes me smile, the story enhances it.