A Good Theistic Argument?
Chris Hallquist has blogged on The argument from moral agency. The argument was formulated by an agnostic philosopher and praised by two atheist bloggers, which stirred my curiosity. What is the argument?
In a nutshell, the argument is that moral agents (those who can choose for right or for wrong) have a good chance of existing under the God hypothesis but a really awful chance of existing if God does not exist (Draper uses the fine-tuning data to help support this view).
Knowing how likely it is for moral agents to exist under atheism requires knowing (1) how likely it is to have a universe that can support life (2) how likely a planet that can support life is (3) how often life originates and (4) how often life evolves into moral agents after it originates. What does science say? The science on each of these is very sketchy and uncertain. It is my considered opinion that 1-4 is each very, very improbable. However, I also see good reason to think that each one of them has had a gazillion chances to be actualized in the reality we inhabit. Sentient species may not evolve very often, but there have been billions upon billions of species that have evolved over the course of life’s history, and no doubt many more will evolve before the sun burns out. Life may not originate from a chemical reaction very often, but the earth’s early oceans were doubtlessly creating billions of chemical reactions every day for millions of years before life got started. Life friendly planets may be rare, but then again there are trillions upon trillions upon trillions of planets out there (millions of stars in every galaxy and an estimated 100 billion galaxies, and I’ve even seen estimates as high as 500 billion). Last week, we saw that it is fairly certain we inhabit just one universe among a large plethora of universes. And that last one is really important, because chaotic inflation may produce infinite universes (or at least an incredibly large number of universes). Infinite universes = infinite planets, infinite opportunties for life to arise, and so on, making it certain that it would happen somewhere in the vastness of eternity. A really gigantic (but not infinite) number of universes would still pump up the chances of having moral agents by quite a bit.
So, the probability of moral agents under naturalism changes quite a bit when you take into account what we know about reality. How much does it change? Again, it’s hard to stick any exact numbers on this type of thing, but I can’t see any good reason to think moral agents are less probable under atheism than theism once we take into account the vastness of reality. We could pretend the likelihood of each one of those factors is “one out of a hundred billion,” but we’ve got good reason to think each of them has had or will have over a hundred billion chances to happen. Therefore, it will happen. No god required.