Thursday, July 8, 2010

Fine-tuning? Really?

The other day my daughter said something that made me burst out laughing.  When we take long trips in the car (which is anything more than half an hour for children), my daughters and I spend a lot of time pretending.  On that particular day, the sky ahead of us started to become overcast and I said it looked as though it was going to rain.  A few seconds later, the rain came and, to kick off our pretending, I exclaimed "I said it would rain and it does. I control the rain!"  To this my oldest daughter replied "Oh yeah? Then make it stop." Clever girl.

This post marks the fourth installment of my review of William Lane Craig's Five Arguments for God. This time I'll be tackling The Teleological Argument from Fine-Tuning. The argument typically goes something like this:

1. The universe is fine-tuned
2. This fine-tuning is the result of  either physical necessity, chance, or design.
3. It is not due to physical necessity or chance
4. Therefore, the universe was designed

Now there are two things here I'd like to point out.  The first is that, once again, this argument for god makes no mention of god.  At best it argues for design of the universe. The second thing that bears mention is that, also once again, it is not clear in what sense the word universe is used.  Perhaps this argument does show that the (cosmological) universe was designed, but does it show that the (philosophical) universe was?

In his formulation Craig leaves off the first premise, although he does go through an introduction that essentially explains the premise. I include it here because I believe it will be helpful in identifying an underlying assumption.

What does it mean to say that the universe is fine-tuned?  When proponents of fine-tuning speak of it, they talk about this or that universal constant/ratio/etc. being very precise, such that a small change to them drastically alters the cosmological landscape. So is that it? Is fine-tuning simply saying that if things were different that things would be different? Of course not. Craig is kind enough to clarify here and let us know that fine-tuning is in reference to the existence of intelligent life. According to Craig, if these constants and ratios were slightly different, intelligent life would not be possible.

Here then, lies that hidden assumption I mentioned.  If fine-tuning is in regards to intelligent life (life as we define it mind you) and if it is to be at all meaningful, one must assume that the aim of the universe was the production of intelligent life. This, in turn, assumes a purpose or intent to the universe, which assumes some guiding force, and suddenly we're begging the question.

Let me illustrate with an example. Let us say that I take a half dozen paint-filled balloons and throw them randomly at a canvas.  The resulting image is (roughly) that of a man in profile.  Were my throws fine-tuned to produce that image? No, they were not.  They were random and just happened to create the image.  Now let's repeat this example with a slight modification. This time, before I throw the balloons, I sketch out a man in profile which matches the image the balloons create. In this case, my throws were fine-tuned because I had an intended image before I began.

Having exposed fine-tuning for what it is, we have effectively vanquished the fine-tuning argument. Still, there are enough additional flaws that I think a little dead-horse-beating is useful.  Sticking with the first premise, let's examine these constants and ratios that Craig believes are so fine-tuned. 

It turns out that they are not as awe-inspiring as Craig would have us believe. Many of the constants, including the gravitational constant Craig uses as an example, are artifacts of the unit system we are using.  As it so happens, these constants can be changed with no effect on the physics.  Really, then, no fine-tuning there. The ratios fare no better, quite often being required by the laws of physics.

Another problem with the fine-tuning premise, or at least Craig's explanation of it, is the range of variation for these values. Craig says that if they are altered less than a hair's breadth, the balance would be destroyed. Not being up to speed on the latest technical jargon, I'm not certain what numerical value a hair's breadth represents. As it turns out, the amount of variance changes between constants/ratios and is not always necessarily small, even when it is phrased to seem that way. (For example, saying that if I were only 1/10^16 of a light-year taller, I would be one of the tallest people on earth looks like a small change, but when you work it out, you realize that it's a change of approximately 3 feet.) Again, this doesn't exactly sound fine-tuned.

I'm not done with that first premise yet, because now we need to examine the claim that a change to these values would have such a drastic effect.  The scientific community, specifically those people who are involved in the relevant fields of cosmology and physics, do not seem universally impressed. Dozens of papers disputing the idea of fine-tuning exist. Victor Stenger (who just so happens to identify himself with the New Atheists that Craig mentions in his paper) provides an excellent guide to those wishing to know more about the scientific flaws of fine-tuning.

Because I was so harsh on the first premise, I'll go relatively easy on the second.  Honestly, there's not much to say about it, except that it brings up that hidden assumption again.  Because fine-tuning implies intent, nature and chance aren't going to get a fair shake.

The third premise says just that. Nature and chance don't explain fine-tuning. Of course they don't. Saying that something was fine-tuned (unless it is meant in a trivial sense) rules out nature and chance. So instead of talking about fine-tuning, let's talk about the way things are.  Does nature or chance provide a reasonable explanation for the values of these constants and ratios? Yes, they do, as I've explained above. Once you drop the assumption of intent, nothing rules out either option.

Chance, in particular, gets a bum rap because people don't understand it.  It's easy to say that the odds of something happening are 1 in some large number, so isn't it amazing that it happened.  The problem is extremely unlikely events occur every day. That something has low odds of occurrence does not mean that it cannot occur even as the result of a single random instance.

The order of cards in a normal deck of 52 playing cards can be any one of 8.06582 x 10^67 possibilities. Restated, the odds of any specific order of those cards is 1in 8.08582 x 10^67, very low odds by most standards. Thoroughly shuffle those cards though and one of those orders will occur.  Because the odds of that order are so low, should we assume that it was fine-tuned.  Chance and randomness easily explain low odds events if we don't make the mistake of privileging the outcome after the fact.

Coming to the conclusion now, we can see that it just doesn't hold.  There are too many problems with the fine-tuning scheme to merit a conclusion of design. Defusing it turns out to be a matter of asking a question much like my daughter did. Would the universe be pointless if it didn't produce intelligent life? Forgive me for finding that a little conceited. The rain doesn't fall because I tell it to and the universe isn't here for the purpose of producing me.

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