Why, though, limit the possible explanations to an intelligent agent or an unintelligent multiverse? Jonathan Witt at Evolution News explains:
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.Here's what Witt says about the multiverse hypothesis:
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 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.
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.Witt gives a couple more illustrations of what he sees as the fallacy in invoking the multiverse to explain the unimaginably high improbability of an undesigned universe being as fine-tuned as is ours, and you might want to check out his column if this topic interests you.
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.