Month: January 2025

Theisms, naturalisms, and fine tuning

Basic Stuff

Basic Theism =  

  1. There is a supernatural a creator of the universe 
  2. They set the parameters for physics 

Basic Theism generates no expectations over what the parameters of physics end up being. If there are a million different ways the parameters could be set supernaturally, then our expectations of any one in particular becoming actual should be one in a million. It is a flat probability distribution.    

Basic Naturalism =  

  1. There is no supernatural a creator of the universe
  2. The parameters for physics are determined naturally

Basic Naturalism generates no expectations over what the parameters of physics end up being. If there are a million different ways the parameters could be set naturally, then our expectations of any one in particular becoming actual should be one in a million. It is a flat probability distribution.    

The fact that the basic parameters of physics are finely tuned for life is not evidence for Basic Theism over Basic Naturalism. They generate exactly the same predictions, and so the evidence of fine tuning is completely neutral between them.  

Enriched Stuff

Enriched Theism =  

  1. There is a supernatural a creator of the universe 
  2. They set the parameters for physics 
  3. They desire for there to be life 

The standard idea here is that Enriched Theism generates a non-flat probability distribution across all the possible ways the parameters of physics could be set. Because they desire for life, the enriched god is more likely to pick worlds where there could be life; that is, she would be more likely to pick worlds where the laws of nature allow life to exist. For any pair of worlds, w1 and w2, if the parameters of physics allow for life in w1 and not in w2, then (on Enriched Theism) we should expect w1 more than we do for w2.  

Enriched Naturalism = 

  1. There is no supernatural a creator of the universe 
  2. The parameters for physics are determined naturally 
  3. Nature has a metaphysically necessary disposition (somehow) towards setting values for the parameters of physics that allow for life 

It seems to me that Enriched Naturalism generates exactly the same expectations as does Enriched Theism. Let’s just specify that the disposition assigns exactly the same probabilities as does the desire in Enriched Theism.   For any pair of worlds, w1 and w2, if the parameters of physics allow for life in w1 and not in w2, then (on Enriched Naturalism) we should expect w1 more than we do for w2.

The fact that the basic parameters of physics are finely tuned for life is not evidence for Enriched Theism over Enriched Naturalism. They generate exactly the same predictions, and so the evidence of fine tuning is completely neutral between them.  It’s still a tie.

Breaking the tie

We could, of course, try to break the tie by comparing something basic with something enriched. For example, compare Basic Natualism and Enriched Theism. Now the evidence that the parameters of physics are finely tuned for life does favour Enriched Theism (over Basic Naturalism). Basic Naturalism assigns each possible way the parameters could be set an equal probability to every other. Enriched Theism favours worlds where there could be life (like worlds where the parameters are finely tuned for life), and assigns them a higher expectation value.  

But that’s not interesting. We could equally well say that the evidence favours Enriched Naturalism over Basic Theism. After all, Enriched Naturalism generates exactly the same expectations as Enriched Theism. It’s a perfect symmetry. When we compare apples with oranges, the one simpler theory predicts less and so it loses out. When we compare oranges with oranges, it’s a tie.

Stalking horse hypothesis

Let the ‘stalking horse hypothesis’ just be the hypothesis that for any possible enrichment of Basic Theism (by adding auxiliary assumptions), there is a mirror version of enriched naturalism which generates exactly the same predictions. If so, there’s never going to be an oranges to oranges comparison of the type considered here where fine tuning favours theism over naturalism. There will always be a suitable orange ready at hand to be the relevant comparison, guaranteeing the tie.

Is it possible to prove this hypothesis? Not sure at the moment. It’s an interesting idea though, I think.