Sir John Polkinghorne, the eminent British theoretical physicist-turned-Anglican priest, has a favorite example of what is often called the “fine-tuning” of the cosmos for life.

It’s currently thought that there’s a sort of energy that’s driving the expansion of the universe and that’s linked, simply, with space itself. The most common term for it is “dark energy.” (Formerly, it was termed the “cosmological constant.”)

The strength of this “dark energy” has recently been measured, and it turns out to be much less than what physicists would have predicted it to be. If the data are accurate, the measured value of the dark energy observed by scientists is 10 to the minus 120 times the value that would naturally be expected. In order to represent that figure as a fraction, you would need to write a numerator of one above a denominator of one followed by 120 zeros. (Try writing it out!)

That is, in fact, an astoundingly small fraction. To put it in perspective, the number of atoms in the entire observable universe is estimated to be somewhere between 10 to the 78th and 10 to the 82nd power — that is, between one followed by 78 zeros and one followed by 82 zeros.

If the number were any larger, remarks Polkinghorne, life would be impossible.

And this is just one of a rather large ensemble of numbers that appear, according to contemporary science, to have been precisely fine-tuned to allow for galaxies, stars and life.

How can such things be explained? One obvious way is to see them as indicators of deliberate, intelligent purpose undergirding the universe. On this reading, they point to some sort of powerful mind — or, in other words, to what most people worldwide would call “God.” Polkinghorne is not alone among scientists and philosophers in leaning toward such an understanding.

Another way to explain them is to say that there are many universes, perhaps an infinite or virtually infinite number of them, within an overall “multiverse,” and that we just happen to have lucked out. If our particular universe weren’t as it is, we wouldn’t be here to notice it.

Unfortunately, though, essentially by definition, it’s difficult — if not impossible — to think of a way of ever knowing about such alternate universes, if they really exist. And it’s somewhat amusing to listen as people who disdain faith in an unobserved and unprovable God take refuge, when confronted with the possible religious implications of “fine-tuning,” in the concept of unobserved and unprovable other universes.

A third way of reacting to these new discoveries is simply to accept that that’s just the way the universe is, a brute fact not to be questioned, and to focus on other things. But that seems a curiously unscientific response.

The Canadian philosopher John Andrew Leslie has created a parable to help us think about this question:

Suppose that you’re about to be executed. Ten skilled marksmen armed with rifles are lined up a few feet away; you’re blindfolded and placed against a wall. You hear the officer say “Fire!” and the rifles roar. However, to your surprise and relief, you’re still alive. Untouched, even.

How do you react?

Do you simply respond that, well, that’s the way it is, and then walk away without any questions? Such a reaction would be remarkably incurious, even extremely strange.

Alternatively, you might reason that even the best riflemen sometimes miss and that, if enough executions happen, there must surely be one, somewhere, sometime, in which all 10 members of the firing squad completely miss their target at close range. You simply happen to be the lucky one. Question disposed of. Move along. There’s nothing more to see.

However, Polkinghorne, with many others, finds a third hypothetical response most reasonable. “Maybe,” summarizes Polkinghorne, “there is only one execution scheduled for today, namely yours, but more was going on in that event than you are aware of. The marksmen are on your side, and they missed by design.”

And so it is, he believes, with the universe as a whole.

Sir John Polkinghorne has written prolifically on science and religion. A brief and accessible introduction to his thinking can be found in the remarkable volume of essays edited by Eric Metaxas under the title of “Socrates in the City,” or, in its paperback edition, “Life, God, and Other Small Topics” (Dutton, $17). I recommend the entire book enthusiastically.

Daniel Peterson teaches Arabic studies, founded BYU's Middle Eastern Texts Initiative, directs, chairs, blogs daily at and speaks only for himself.