Jan 08 2015

The Science of God

Recently Eric Metaxas wrote an opinion piece in the Wall Street Journal in which he argues that, “Science Increasingly Makes the Case for God.” (Sorry, it’s behind a paywall, but I will quote the salient parts.) Metaxas is an author and speaker, but not a scientist, and it shows in his writing.

His essay is based on two instances of the anthropic principle, which simply notes that in order for life to exist the universe must possess conditions compatible with life. He applies the anthropic principle to the Earth specifically and to the universe as a whole. Starting with the Earth he writes:

As factors continued to be discovered, the number of possible planets hit zero, and kept going. In other words, the odds turned against any planet in the universe supporting life, including this one. Probability said that even we shouldn’t be here.

Today there are more than 200 known parameters necessary for a planet to support life—every single one of which must be perfectly met, or the whole thing falls apart. Without a massive planet like Jupiter nearby, whose gravity will draw away asteroids, a thousand times as many would hit Earth’s surface. The odds against life in the universe are simply astonishing.

He states this as if it is an accepted scientific fact without any kind of reference. It is hard to know, therefore, exactly what he is talking about. What are these 200 known parameters? The only references I can find to such a claim is from Christian apologist sites trying to make the case for god, as is Metaxas.

This site, for example, lists 68 parameters. In them we can see the error in logic that this line of argument is making. First, Metaxas is being imprecise with his wording. He is referring to “advanced life,” not any life. If we assume that he is talking about complex life as it exists on Earth, he is still making a massive error in logic – a common error referred to as the lottery fallacy.

Essentially Metaxas and other apologists are asking the wrong question – what is the probability of the kind of life found on Earth coming into existence. This is like asking what the probability is of John Smith winning the lottery, rather than asking the better question, what is the probability of anyone winning the lottery.

Of course life on Earth is fine-tuned for and takes advantage of conditions on Earth, because that is where it evolved. Lawrence Krauss correctly points out in an open letter to the WSJ:

This is more likely an example of life being fine-tuned for the universe in which it evolved, rather than the other way around.

We only have one example of life. It seems likely that there are very different beings on a very different planet in another part of the universe marveling at how well suited their environment is for them.

Going through lists of alleged parameters it is also clear that Metaxas is massively overstating his case. There is no reason to believe that each parameter (if it has to be met at all) has to be “perfectly met.” As we are increasingly learning from extremophiles, life can evolve to adapt to a wide range of conditions. Conditions that we would find hostile might be perfectly comfortable to life that evolved in those conditions.

In fact if anything over the recent decades scientists have discovered that life can probably exist over a much wider range of conditions than previously imagined. Life in the universe is getting more likely, not less.

Metaxas is also partly falling for an Earth-centric bias. For example, we think of stars and therefore planets as existing within galaxies. However, in 2014 scientists discovered that as many as half of all stars exist in the space between galaxies. This just doubled the number of stars in the universe that can host planets and life. Also, life is probably safer between the galaxies, far away from gamma ray bursts and supernovae. Perhaps more life exists between galaxies than within them.

There are also more rogue planets in the galaxy than planets around stars. Conditions on rogue planets are likely to be very different from Earth, but that doesn’t mean they can’t support complex life. Again, I can imagine beings on a rogue planet assuming incorrectly that life on a planet near a star would be impossible.

Assuming that every one of these alleged 200 parameters need to be perfectly met also makes many unwarranted assumptions. It ignores, for example, the role that life plays in the homeostasis of the environment.

Metaxas then follows up with:

There’s more. The fine-tuning necessary for life to exist on a planet is nothing compared with the fine-tuning required for the universe to exist at all. For example, astrophysicists now know that the values of the four fundamental forces—gravity, the electromagnetic force, and the “strong” and “weak” nuclear forces—were determined less than one millionth of a second after the big bang. Alter any one value and the universe could not exist. For instance, if the ratio between the nuclear strong force and the electromagnetic force had been off by the tiniest fraction of the tiniest fraction—by even one part in 100,000,000,000,000,000—then no stars could have ever formed at all. Feel free to gulp.

Multiply that single parameter by all the other necessary conditions, and the odds against the universe existing are so heart-stoppingly astronomical that the notion that it all “just happened” defies common sense. It would be like tossing a coin and having it come up heads 10 quintillion times in a row. Really?

This is just the old anthropic principle argument. Yes – the physical properties of the universe allow for complex life. But again Metaxas is committing the same lottery fallacy again.

It is possible that the laws of the universe are not random (as Metaxas is assuming with his coin-flipping analogy). Perhaps they have to be what they are for some deeper reason. We just don’t know.

It is also possible that there are many configurations of physical laws that allow for complex life (although very different from our own), and this is just one.

It is also possible that there are many universes, perhaps even infinite. In those universes where the laws are such that complex life is allowable, such life would consider itself highly unlikely – just like every lottery winner considers themselves extremely lucky and must marvel at the impossible odds that led to their win.


Metaxas’s arguments fail on multiple levels. I also found them not only unconvincing, but profoundly lacking in that he did not even acknowledge the counterarguments that are already out there. Either he ignored them or was unaware of them.

I also found his arguments an excellent example of motivated reasoning. He is trying a bit too hard to make the scientific case for god, grossly exaggerating his position and ignoring counterarguments.

We currently do not know how common life in general, complex life, or intelligent life is in the universe. There are simply too many variables, and we do not yet understand the full possibilities for which this universe might allow. The universe might be teeming with complex life. It is also quite possible that life as we know it on Earth is very rare, perhaps even unique. As Sagan himself noted, someone has to be the first intelligent species in the universe, and they would correctly find themselves to be unique.

Perhaps we have won the cosmic lottery. That does not mean there is a purpose behind our existence.

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