There is a story about turtles which has been around for a long time in one form or other.  The story is used to illustrate the philosophic problem of infinite regression—which has also been around a long time (even longer than the story about the turtles) although not everybody has noticed that infinite regression is a problem except philosophers, scientists and other similarly persnickety people.

What problem? Ben Stein asks. There isn’t a problem.

The problem of infinite regression is a problem in bad logic, and some people hate bad logic.  And so they tell the story about the turtles.

Or the enormous elephant.

When John Locke told the story in 1690, his version involved an enormous elephant and lacked the kicky punch line of the story as related by Stephen Hawking, theoretical physicist, superstar scientist and raconteur.  In Hawking’s telling, which is to be found in his A Brief History of Time, a prominent scientist, possibly Bertrand Russell—after giving a lecture about the earth and the sun and the galaxy—is challenged in his cosmology by an elderly woman in the audience.

You’re wrong, insisted the woman. The world is a flat plate balanced on the back of a turtle.

If that is so, the scientist asked, what is the turtle standing on?

“You’re very clever, young man, very clever,” says the woman. “But it’s turtles all the way down.”

Which of course naturally leads to the topic of intelligent design.

Intelligent design has been put forward as an idea which—according to its advocates—is a legitimate scientific idea—upright, clean and morally good—which should be taught in the schools along with evolution, or instead of evolution.  The premise is that there are some structures in nature too complex to be the product of evolution, that is, of random variation subject to natural selection. If evolution could not have produced such complex structures all on its own—and it really couldn’t, insist the advocates of intelligent design—an intelligent hand must have gotten directly involved.

Oh, really.

Evolution can make a tree, says the intelligent designer, but eyes can only be made by higher intelligences like me.

But what is the intelligent designer standing on?

Critics of intelligent design say that the idea is merely creationism dressed up and made to act polite; that it is not a scientific theory but merely religious doctrine with little or no actual scientific content.  

Science by its nature is about testable things.  Articles of faith such as the existence of an intelligent designer, concepts which can neither be proven or disproven, do not belong in science and that is because science has nothing to do with unprovable things.  Sorry.  That rule is written into the definition of science.

Oh no, say its advocates, crossing their fingers behind their backs, we didn’t say it was GOD who was the intelligent designer.  We never said God, no one heard us say God, you can’t prove a thing.

But it's not even a legitimate scientific theory, point out the critics of intelligent design.   Merely insisting that certain structures could not have been produced by evolution is not an argument that stands on its own.  Couldn't have happened?  On whose say-so?  Who can claim that level of understanding of nature that they can say what it is or is not capable of doing--given a planet to play with, life multitudinous, and fourteen billion years to do it in?

Have we figured out nature's every trick?  No sirree.

There are many things that seem impossible at first glance, as anyone realizes who has ever been to a good magic show. Yet an intimate knowledge of what goes on behind an illusion can transform the impossible into the clever but perfectly reasonable.  To see behind the illusion, though, you must first learn how a trick is done, see all the steps gone through by the illusionist, and learn to ignore the misdirection which steers you to illusion.

No reputable scientist discussing evolution would ever insist they knew everything there was to know about it.  Nor would they ever insist that they could not be fooled, and that therefore a trick which they could not figure out must be not be a trick at all.  It must be real magic.

But intelligent design advocates argue exactly that, that they can’t be fooled, and that therefore there must be an intelligent designer.

Anyway, postulating such an intelligent designer merely begs another question.  A perplexing question when you're not allowed to evoke religion.

Because, you see, if an eye is too complex for nature to come up with, then where did theintelligent designer come from?  (And was the designer eyeless?)

Intelligent design says that extreme complexity presupposes a designer.  Yet what could be more complex than the intelligent designer?  That being so, the question arises of who or what designed the intelligent designer? And who or what designed the being who designed the intelligent designer?  And who or what designed the being who designed the being who designed the intelligent designer?  And so on. And so on.

It’s turtles, you see.

All the way down.