Aug 13 2015

Does Science Prove God?


I could just stop there, but I’ll elaborate. Earlier this year Prager University posted a Youtube video hosted by Eric Metaxas in which he argues that science is the best argument for the existence of god. (The text is the same as his 2014 WSJ article.) It was nothing surprising – he simply trots out the old fine-tuning of the universe argument. (I wrote about this here, but it’s making the rounds again so I’ll take another swipe.)

He starts, however, by quoting Carl Sagan from a 1966 Time article. Sagan said that there were only two criteria for life to exist, the right kind of star and a planet the proper distance from that star. he wrote:

Given the roughly octillion—1 followed by 24 zeros—planets in the universe, there should have been about septillion—1 followed by 21 zeros—planets capable of supporting life.

This of course was a rough order of magnitude estimate based upon what information we had at the time, prior to any exoplanets being discovered. Metaxas then goes on to argue that since Sagan science has discovered that there are more than 200 factors, and the number of potential planets therefore has shrunk to “thousands.”

I cannot find any reference to what these 200 factors are outside of his book, which I have not read. There is no scientific basis for it that I, or anyone else, apparently, can find. He names a few, the role of Jupiter in protecting the Earth from asteroids, for example.

There are several major problems with this line of argument. The first is that he is moving the goalpost. Sagan was talking about “life” and Metaxas changed the criterion to advanced intelligent life without explicitly stating that he was doing so.

In fact, I think Sagan was being too pessimistic. Since then we have learned that most stars have a planetary system. Most are not like our own, true, but current estimates are that there are perhaps 20 billion Earths in our own galaxy.

Life, however, is probably more versatile than that. There may be life in the oceans beneath the surface of Europa, for example. If there is, think of the number of moons of gas giants that may harbor life. The “habitable zone” around stars could be much more vast than we think.

Further, there may be as many as 100 quadrillion rogue planets in our galaxy – planets wandering between the stars. While certainly most of these worlds are frozen and dead, some may have conditions where life is possible. Gas giants may have moons of ice and subsurface oceans warmed by tidal forces, for example, with life living off of chemical energy or geothermal.

If anything science has increased the possibility for life in the universe since Sagan.

But let’s take Metaxas’s unstated criterion for advanced life, not just life. There are no scientific sources that establish his “more than 200 parameters” claim. Given his examples, however, it seems clear that he is basing this claim on a dubious premise, that the conditions on Earth are necessary for any intelligent life.

This assumes that the particular conditions on Earth are the only ones that could result in the long term stability necessary for intelligent life to develop. This is an unreasonable assumption, given the number of systems and planets out there in the universe. Perhaps there are billions of configurations that will do, and we know of only one.

Metaxas is also making the classic “puddle” fallacy – that of a puddle of water marveling at the fact that the hole in which it exists was perfectly formed to hold it. Obviously it is the water that is conforming to the hole.

Likewise, life evolved to adapt to the conditions on Earth, and it is just as absurd as the puddle to think that Earth was made to perfectly support the life that is on it.  Life could adapt to a wide range of conditions, including temperature, radiation level, environmental variability, tides, atmospheric pressure, etc.

Alien life that evolved on a planet extremely hostile to humans would likely think their world is perfect. Another perfect day in paradise, the acid levels are just right, it’s comfortably below the boiling point of water, and both suns are in the sky.

Here is a list of 68 conditions supposedly necessary for life. Looking through the list it is clear that, first, the list is massively padded. Further, the criteria are very narrow. It’s ridiculous to think that life could not adapt, for example, to a slightly different iron content in the soil.

Finally Metaxas commits the classic lottery fallacy. He argues that since the Earth is so statistically unlikely it is absurd to think that it occurred by chance alone. This is identical to thinking that because winning the lottery is 100 million to one against, whoever wins could not have won by chance alone. For someone who did win, they may have the overwhelming sense that it was destiny, because their win was so unlikely.

But someone eventually is likely to win the lottery. That someone won is actually quite likely.

Similarly, that there is life, even advanced life, somewhere in the universe, given the size of the universe and the number of possibilities, is almost certain. Even very unlikely events, given enough opportunity, become very likely.

We are clearly the winners of the cosmic lottery, and it would be a fallacy to argue that therefore it could not have been by chance. An octillion planets is still a huge number. Metaxas’s argument actually contains its own refutation.

Metaxas then goes on to state the fine-tuning of the universe argument. He supports this argument with the classic creationist trick of quoting people out of context. He even quotes Christopher Hitchens as saying that the fine-tuning argument is the best argument of the other side. He completely ignores, however, Hitchens’ refutation of this argument.

Essentially this is a god of the gaps argument – we don’t know why the laws of the universe are the way they are, but this does not give licence to simply say goddidit. We don’t know, for example, if there are reasons that the laws have to be the way they are. It’s also possible that there are infinite universes, and only those with physical laws compatible with intelligent life will host intelligent beings contemplating the unlikeliness of their existence.

Perhaps we won two cosmic lotteries, but odds are someone would.

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