Fine Tuning and Physical Necessity

Hello Dr. Craig,
I'm looking for some clarity regarding your argument about the explanation for the fine-tuning of the cosmos for intelligent life, in which you identify either physical necessity, chance, or design as explanatory options.
You rule out necessity by saying that the laws of nature (and/or their values) are contingent and could have been different. This seems intuitively correct to me, and I have heard secular scientists like Brian Green state similar views on his PBS documentary (only in the context of the multi-verse). However, I'm wondering what kind of evidence we have for such a claim (i.e., that the weak/strong nuclear forces or gravity could have taken on different values, or be reversed, or have completely different characteristics all together)?
Evidence aside, you imply (but haven't explicitly stated) that such necessity would be disconfirming of theism. This is inferred by the way you dichotomize necessity from design. However, I don't see why the necessity of physical reality could not be merged with design. Wouldn't a grand unified theory (if it could show that the natural laws and their values COULD NOT have been any different) just bring up an even more important question...that is, 'why does a life permitting universe HAVE to exist?' Would this question be incoherent in the light of proven physical necessity? Otherwise, it seems to me that a proof for the necessity of the physical laws would be strongly confirming of theism (i.e., necessity by design), especially in the absence of a multi-verse.
Aaron
United States

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