According to legend, Bertrand Russell gave a public lecture in which he ridiculed the ancient myth where the world rests on the back of a turtle. Russell pointed out the difficulty that such a metaturtle lives in a metaworld, which needs support just as much as the one we live in. An old woman (cultural deconstructionists, jump right in) stood up and retorted, ``You can't fool us Professor Russell: it's turtles all the way down!''
I don't give this story much credence, but I believe that whenever we think we are looking at the bottom turtle, we only demonstrate the limit of our vision.