Posted: Dec 17, 2011 1:21 am
by jlowder
Thommo wrote:
jlowder wrote:I'm pretty sure I understand the nature of the "multiverse counterargument," as well as the Bayesian version of the fine-tuning argument (FTA). Here's one formulation:

Let F = the apparent 'fine-tuning' of the physical constants of our universe
Let T = classical theism
Let N = metaphysical naturalism

(1) F is known to be true.

I'm not familiar with this formulation, could you perhaps elaborate on this premise (1)?

Hi Thommo -- Sure. (1) basically refers to the fact that the physical constants of our universe make it physically possible for life as we know it to exist in the universe.

Is this intended to be read as "Fine tuning is known to be a feature of the universe" or as "Fine tuning of free parameters in current physical models of the known universe is required for them to accurately describe the known universe"?

Thommo wrote:Because whilst the latter is a reasonable statement the former is indeed refuted by the mere possibility of "many worlds" - consequently where that is the argument being given the refutation is complete.

Of course if the latter of the two statements is intended then (3) is trivially false, as F becomes independent of both T and N, meaning that even the simplistic statement of "Many worlds is possible" is overkill as a refutation.

So I can only assume you perhaps intend it to mean something else?

Like all inductive or evidential arguments, appeals to possibility do nothing to undermine to the claim about probability. Yes, it is possible there is a multiverse and F is merely the result of chance. But that bare possibility does not refute or even contradict premise (3), which says that F is antecedently very much more probable on theism than on naturalism, i.e., Pr(F/T) >!! Pr(F/N).


Jeffery Jay Lowder