I was waiting for someone to bring this up in the combox on my recent post on Swinburne’s cosmological argument, but no one did. The argument from consciousness (to theism) is a parallel argument to the cosmological argument against theism.
In the cosmological argument against theism, I pointed out that naturalism entails a physical universe whereas theism does not. Since a physical universe exists, it follows that the universe is evidence favoring naturalism over theism.
The parallel argument based on consciousness goes like this. Theism entails that consciousness exists whereas naturalism does not. Since consciousness does exist, it follows that consciousness is evidence favoring theism over naturalism.
We formalize this as follows. Let B be our background information; E be the existence of human consciousness; T be theism; and N be naturalism. Here is the explanatory argument.
1. E is known to be true, i.e., Pr(E) is close to 1.
2. N is not intrinsically much more probable than T, i.e., Pr(|N|) is not much greater than Pr(|T|).
3. Pr(E | T) =1 > Pr(E | N).
4. Other evidence held equal, N is probably false, i.e., Pr(N | B & E) < 1/2.