Doctor Logic and Lydia McGrew on Likelilhoods, Design, and Probabilities

Doctor Logic: If an all powerful being were designing life, we don't expect descent, common descent, common composition or a gradual appearance of features and species. How many ways can a God create life in a universe? The number of ways a God can do this is vastly greater than the number of ways unguided evolution can do so. For example, gods don't even need to create life consistent with physical laws because they can create ghosts. There's no need for descent (birth) because God can make animals outright or create factories (no car has ever been born to another car). Even keeping the species the same and changing their natural histories and genomics gives a God vastly more options than evolution. I think theists would be tempted to say that there are infinitely more ways God could create life than ways that evolution could create life.


This is a simple problem in Bayesian reasoning. Finding ourselves in a world that is consistent with unguided evolution implies that the probability that we're designed is extremely close to zero.

In other words, if God exists, then there are a million ways in which God could create things, including Young Earth Creationism, etc. If atheism is true, then if intelligent life is going to emerge, it's got to emerge through naturalistic evolution. So, if the evidence is compatible with naturalistic evolution, then the evidence very strong supports naturalistic evolution, since this evidence is very likely given atheism and vanishingly unlikely given theism.

Lydia McGrew's paper on design and likelihoods might serve as a way for theists to respond here. Because God could do it a certain way doesn't mean that it would be reasonable for God to do so.