Two Fedoras

After having heard a lecture given by the philosopher and psychologist William James concerning the solar system, a woman rose to her feet and explained that the Earth does not circle the Sun and that it it instead insisted that it rode atop the back of an enormous turtle. Mr. James questioned the woman asking “If your theory’s correct, madam, what does this turtle stand on?” “A second far larger turtle, of course!” she snorted back. “But what does that stand on?” pressed the philosopher. “It”s no use, Mr James”, snorted the old lady triumphantly, “it”s turtles all the way down!”

Finally, this video comes along and provides us with conclusive evidence that the woman was not entirely accurate in her description of the universe. It’s clearly not turtles all the way down, as the order is observably and thus empirically established to be “Cat, Tortoise, World, Turtle, Turtle, Turtle, …”

source: QI’s Stephen Fry & Geekologie