A simple design argument
December 1, 2010 — 16:35

Author: Alexander Pruss  Category: Existence of God  Tags: , , , ,   Comments: 43
  1. P(the universe has low entropy | naturalism) is extremely tiny.
  2. P(the universe has low entropy | theism) is not very small.
  3. The universe has low entropy.
  4. Therefore, the low entropy of the universe strongly confirms theism over naturalism.

Low-entropy states have low probability. So, (1) is true. The universe, at the Big Bang, had a very surprisingly low entropy. It still has a low entropy, though the entropy has gone up. So, (3) is true. What about (2)? This follows from the fact that there is significant value in a world that has low entropy and given theism God is not unlikely to produce what is significantly valuable. At least locally low entropy is needed for the existence of life, and we need uniformity between our local area and the rest of the universe if we are to have scientific knowledge of the universe, and such knowledge is valuable. So (2) is true. The rest is Bayes.


A family of design arguments
August 10, 2009 — 13:22

Author: Alexander Pruss  Category: Existence of God  Tags: , ,   Comments: Off

A standard kind of design argument is one that takes a nomic generalization, and asks why the law in question holds. One can either ask about particular laws (e.g., fine-tuning arguments do that) or about why there are laws at all. I have nothing against such arguments, but I want to suggest that it’s worth thinking about a different family of design arguments: arguments from non-nomic generalizations in science.

Here are some generalizations that appear to be non-nomic:

  1. Every species on earth, with the exception of one root species, has an evolutionary explanation of its existence.
  2. Every particle is a P1 or a P2 or … or a Pn. (Here, n is a small finite number, many orders of magnitude smaller than the number of particles in existence. Physics isn’t yet capable of making this generalization, since we don’t yet have a complete list of all particles.)
  3. Every planet in the solar system is in approximately the same orbital plane.

Now, in some cases, one might seem to have a perfectly fine physical explanation. It seems we can explain (3) in terms of the way our solar system actually formed from a bulgy disc around the sun. There may, further, be facts that imply that this method of planetary formation is much more probable than other methods, given the initial conditions. But, while I am willing to concede this case, I want to make two points. The first point is that the explanation may well end up depending on non-nomic (and perhaps only statistical) generalizations about the initial conditions of our universe, so the problem may simply get pushed back. The second is that the explanation depends on the principle that nothing can come from nothing. After all, if planets could come into existence ex nihilo, then to explain why all planets in the solar system have coplanar orbits would require us to explain why no new planets came into existence ex nihilo with weird orbits. And it is not clear that one can, in the end, defend the principle that nothing comes from nothing without defending the most controversial premise of the cosmological argument.