This month’s blockbuster Marvel comic book movie Dr. Strange will serve as many people’s introduction to the exotic idea of the multiverse, the notion that besides our universe there are a host — maybe an infinity — of unseen other universes, some radically different from our own, some highly similar but distinct in crucial ways.

The film is a worthy and thought-provoking entertainment, but an idea that serves as a good plot device for imaginative counterfactual play in the realm of fiction becomes something very different when taken as an article of faith and used as an explanatory tool in science.

You see, there’s a big divide running through physics, astronomy, and cosmology, and the idea of a multiverse is at the center of the controversy, serving as a crucial means of explaining away some powerful evidence for intelligent design.

The Fine-Tuning Problem

On one side of the controversy are scientists who see powerful evidence for purpose in the way the laws and constants of physics and chemistry are finely tuned to allow for life — finely tuned to a mindboggling degree of precision.

Change gravity or the strong nuclear force or any of dozens of other constants even the tiniest bit, and no stars, no planets, no life. Why are the constants just so? Here’s what Nobel Laureate <href=”#v=onepage&q=leads%20us%20to%20a%20unique&f=false”>Arno Penzias concluded: “Astronomy leads us to a unique event, a universe which was created out of nothing, one with the very delicate balance needed to provide exactly the conditions required to permit life, and one which has an underlying (one might say ‘supernatural’) plan.”

Nobel Laureate George Smoot is another, commenting that “the big bang, the most cataclysmic event we can imagine, on closer inspection appears finely orchestrated.” Elsewhere Smoot describes the ripples in the cosmic background radiation as the “fingerprints from the Maker.”

On the other side of the divide are those who insist with Harvard’s Richard Lewontin that they simply cannot “let a divine foot in the door.” In the case of the fine-tuning problem, they keep “the divine foot” out with a pair of curious arguments. Each involves a fallacy, and one of them the idea of a multiverse.

Fine Tuning and the Firing Squad Fallacy

The first of these goes like this: Sure the universe is fine tuned for life. What did you expect? If it weren’t we wouldn’t be here to register our good fortune.

Think of a prisoner in front of a firing squad. The prisoner shuts his eyes. The shots are fired. The prisoner opens his eyes and finds a perfect bullet pattern outlining his body on the wall behind him. “Hey,” the guard at his shoulder exclaims, “it looks like the firing squad had orders to miss!” The prisoner demurs. “No, the bullet pattern is just blind luck. You see, if they hadn’t missed, I wouldn’t be around to notice my good fortune.”

The prisoner’s mistaken reasoning is the same mistaken reasoning used to explain away the fine-tuning pattern in physics and cosmology. Reasonable Question: “What has the ability to produce the fine-tuning pattern we find in chemistry and physics?” Unreasonable Answer: “We wouldn’t exist to observe the fine-tuning pattern if the pattern didn’t exist.”

The unreasonable answer points to a necessary condition for observing X when what’s called for is a sufficient cause for X. Instead of providing a sufficient cause for the fine-tuning pattern, intelligent design opponents change the subject.

Fine Tuning and the Naïve Gambler’s Fallacy

A second tactic for countering the fine-tuning argument to design runs like this: Our universe is just one of untold trillions of universes. Ours is just one of the lucky ones with the right parameters for life. True, we can’t see or otherwise detect these other universes, but they must be out there because that solves the fine-tuning problem.

Consider an analogy. A naïve gambler is at a casino and, seeing a crowd forming around a poker table across the room, he goes over to investigate. He squeezes through the crowd and, whispering to another onlooker, learns that the mob boss there at the table lost a couple of poker hands and then gave the dealer a look that could kill, then on the next two hands the mobster laid down royal flushes, each time without exchanging any cards. Keep in mind that the odds of drawing even one royal flush in this way is about one chance in 650,000. The odds of it happening twice in a row are 1 chance in about 650,000 x 650,000.

At this point, a few of the other poker players at the table prudently compliment the mobster on his good fortune, cash in their chips and leave. The naïve gambler misses all of these clues, and a look of wonder blossoms across his face. On the next hand the mob boss lays down a third royal flush. The naïve gambler pulls up a calculator on his phone and punches in some numbers. “Wow!” he cries. “The odds of that happening three times in a row are worse than 1 chance in 274 thousand trillion! Imagine how much poker playing there must have been going on — maybe is going on right now all over the world — to make that run of luck possible!”

The naïve gambler hasn’t explained the mobster’s “run of luck.” All he’s done is overlook one reasonable explanation: intelligent design.

The naïve gambler’s error is the same error committed by those who appeal to multiple, undetectable universes to explain the “luck” that gave us a universe fine-tuned to allow for intelligent observers.

A Forest Walker and a Lucky Bullet

Take another illustration, this one articulated by philosopher John Leslie to argue against inferring design from fine-tuning, but taken up by Roger White of MIT and cashed out in a very different way. White writes:

You are alone in the forest when a gun is fired from far away and you are hit. If at first you assume that there is no one out to get you, this would be surprising. But now suppose you were not in fact alone but instead part of a large crowd. Now it seems there is less reason for surprise at being shot. After all, someone in the crowd was bound to be shot, and it might as well have been you. [John] Leslie suggests this as an analogy for our situation with respect to the universe. Ironically, it seems that Leslie’s story supports my case, against his. For it seems that while knowing that you are part of a crowd makes your being shot less surprising, being shot gives you no reason at all to suppose that you are part of a crowd. Suppose it is pitch dark and you have no idea if you are alone or part of a crowd. The bullet hits you. Do you really have any reason at all now to suppose that there are others around you?

So there in the dark forest the walker gets shot and thinks, “Gosh, I guess I’m really surrounded by lots and lots of other people even though I haven’t heard a peep from any of them. That explains me getting shot by chance. A hunter’s bullet accidentally found this crowd, and I’m just the unlucky fellow the bullet found.” The reasoning is so defective you have to wonder if the walker got shot in the head and his powers of rational thought were blasted clean out of him.

The Lucky Bullet Fallacies Miss the Mark

In the firing squad analogy, the prisoner infers a lucky bullet pattern (rather than intentional one) based on the fact that if he hadn’t been fortunate enough not to get shot, he wouldn’t be there to observe the interesting bullet pattern. In the forest analogy, the walker mistakenly invokes many walkers on his way to deciding that a lucky bullet unluckily struck him.

The opponents of intelligent design in physics and cosmology often make a great show of being too rational to even consider intelligent design, but they attempt to shoot down the fine-tuning evidence of design by appealing to these irrational arguments. Both arguments go well wide of the mark.

There’s an irony here. The universe is exquisitely fine-tuned to allow for intelligent designers, creatures able to see, hear, and reason, and to design things like telescopes and microscopes that allow us to uncover just how amazingly fine-tuned the universe is. Fine-tuning allows for intelligent designers such as ourselves, but atheists insist we cannot consider an intelligent designer as the cause for this fine-tuning. Fortunately for us, reason is prior to atheism.

Cross-posted at The Stream.