Fine-Tuning 11: Fine-Tuning Doesn’t Imply a Fine-Tuner

I feel obliged to address what I consider to be a gross misunderstanding of fine-tuning from theistic philosopher Hans Halvorson. In an article in Cosmos, Halvorson argues that fine-tuning actually counts as evidence against the existence of God. He writes,

“Suppose that you’re captured by an alien race whose intentions are unclear, and they make you play Russian roulette. Then suppose that you win, and survive the game. If you are convinced by the fine-tuning argument, then you might be tempted to conclude that your captors wanted you to live.

But imagine that you discover the revolver had five of six chambers loaded, and you just happened to pull the trigger on the one empty chamber. The discovery of this second fact doesn’t confirm the benevolence of your captors. It disconfirms it. The most rational conclusion is that your captors were hostile, but you got lucky.

Similarly, the fine-tuning argument rests on an interesting discovery of physical cosmology that the odds were strongly stacked against life. But if God exists, then the odds didn’t have to be stacked this way. These bad odds could themselves be taken as evidence against the existence of God.” – Hans Halvorson

To understand why Halvorson’s objection is so misguided, it suffices to understand the problem with his analogy. In the analogy, the aliens have left the question of your survival up to chance: they have loaded a gun with five bullets, and they have let chance determine whether or not you live.

This is precisely what the design hypothesis is not saying: the designer has left the survival of our universe up to chance. God has not loaded a computer with a list of 10^120 different universes and allowed the computer to randomly select one, leaving it up to chance whether or not the universe is life-permitting. That would be the “chance” hypothesis, which we already considered and ruled out earlier in this series. That is not what the design hypothesis is saying.

The idea behind design is that the designer has designed the universe to be life-permitting. They have twiddled the knobs exactly where they need to be allow for intelligent life, leaving nothing to chance. So whereas the probability of a life-permitting universe would have been infinitesimally small if we were to select a universe at random, the probability of a life-permitting universe is large if a designer has designed the universe to permit life.

Let’s take Halvorson’s analogy to the extreme: suppose the aliens hand you an alien gun with 1,000,000,000 chambers and asks you to play Russian roulette. You fire, and you survive. Then, the alien opens up the chamber and allows you to see that the other 999,999 chambers had bullets. If you’re Hans Halvorson, you would evidently conclude that the the aliens must really, really hate you, since the odds of surviving were only 1 in 1,000,000,000, and you just got really, really lucky. But if you’re more reasonable, you’d conclude that the game must have been rigged: for some reason or another, the aliens must have arranged (or fine-tuned, if you will) the game to ensure that you got the empty chamber. This is the idea behind design: something which appears very improbable might not be, if we can find another explanation for it.

This really isn’t that complicated or unusual. If you were to randomly throw paint on a canvas, the odds of producing a human face would be extraordinarily small. So when you see the Mona Lisa, you conclude that it must have been designed, because the odds of a human face arising by design are much larger than the odds of a human facing arising by chance.

I could keep going, but I hope you get the point. Halvorson’s objection is clearly in error, but it is useful in that it helps us develop a better understanding of the proposed designer: this designer is not like the aliens who leave your survival up to chance; he is like da Vinci, carefully tuning his masterpiece until it is just right.