Science and possible worlds

At least since the 19C, if not earlier (16-17C), there's been an ongoing debate about whether Christianity and science stand in conflict. On the one hand, critics say science has falsified the creation account and the flood account while neuroscience has falsified the immortal soul. I've discussed those allegations on multiple occasions and have nothing new to say at the moment. 

But at a presuppositional level, some apologists argue that the Christian worldview is necessary to justify the scientific interpretation. Elements of this argument include the claim that the rationality of the universe implies a mind behind the universe–while the reliability of human reason needs divine grounding. Likewise, it only works if God created man and the universe in a state of mutual preadaptation, so that the rationality of the universe is at least translucent to human reason, if not altogether transparent. 

I think those are legitimate lines of argument, but rather than flesh them out, I'd like to turn to a different line of argument: 

Stephen Jay Gould (1989) famously argued that evolutionary history is contingent...Gould claimed that if we could rewind the tape of history to some point in the deep past and play it back again, the outcome would probably be different.

Beatty (2006), however, has shown that there are two different senses of ‘contingency’ in play in Gould’s work. In addition to what Beatty calls contingency as causal dependence—basically, sensitivity to initial conditions—there is a second form of contingency that Beatty initially called contingency as unpredictability, but now calls contingency per se (Beatty 2016). These two senses of contingency correspond with two versions of the famous thought experiment that Gould (1989) deployed. Sometimes, Gould imagines rewinding the tape of history, tweaking an upstream variable, and then playing the tape back. On other occasions, he talks about playing the tape back from the same initial conditions. Beatty (2016) thinks that both senses of ‘contingency’ are important, and he takes it that the second sense—contingency per se—must commit us to some sort of causal indeterminism. On the other hand, Turner (2011a) has tried to give an account of this second sense of contingency that is neutral with respect to determinism. His suggestion is that what Gould really cared about was random or unbiased macroevolutionary sorting. Processes such as coin tosses, or random genetic drift, can be random or unbiased (in a sense) without violating causal determinism. One way to think about this is by adopting a frequentist conception of probability: the outcome of a coin toss could be causally determined by small-scale physical influences, but the outcome is still random or unbiased in the sense that over a long series of trials, the ratio of heads to tails will approximate 50:50. 

Finally, historical contingency is a counterfactual notion, and although this issue has not gotten as much attention as it deserves, there is a nascent philosophical literature on historical counterfactuals (Tucker 2004: 227ff; Nolan 2013; Radick 2016; Zhao 2017 in Other Internet Resources). The debate about historical contingency can be construed as a disagreement about the truth of various historical counterfactuals. Gould claimed that if things in the Cambrian had been slightly different, there would be no vertebrates today, let alone humans, while other convergentists claim that humanlike cognitive abilities, language, tool use, and sociality would have evolved even if other things had been different in the past—for example, if the non-avian dinosaurs had not gone extinct.

https://plato.stanford.edu/entries/macroevolution/#HistCont

That's also presuppositional. Is natural history contingent? If so, can we make truth-valued counterfactual statements about natural history (or the future, or that matter)? If that's the case, then what grounds the truth of counterfactual scenarios? According to the correspondence theory of truth, a statement about the past is true if it matches something that happened in the past. But in the nature of the case, counterfactual scenarios never happened in the actual timeline, so what makes them true?

The common explanation is resort to modal metaphysics (i.e. possible worlds). Unexemplified timelines. But that pushes the question back a step. What's the metaphysical basis for possible worlds?

A Christian, or a Calvinist in particular, can say unexemplified timelines inhere in God's imagination and omnipotence. What might have been had God willed an alternative scenario to play out. It may even be the case that these are exemplified rather than unexemplified timelines if God created a multiverse. Unexemplified in our universe, but exemplified in a parallel universe. 

So that's another line of argument for the necessity of the Christian worldview to underwrite the scientific enterprise. Of course, that also needs to be fleshed out. But it's another promising strategy.