A1: God exists
A2: Plantinga has successfully argued for one of his big conclusions in Warranted Christian Belief: that if God exists, then belief in God is likely to be warranted.
Now, suppose Smith has a properly basic belief that God exists. Smith has also read WCB and believes the conclusion of Plantinga's argument on the basis of that argument. Can Smith appropriately reason as follows?
1) God exists
2) If God exists, then my belief that God exists is likely to be warranted.
3) Therefore, my belief that God exists is likely to be warranted.
Granted, there is some circularity going on here. Smith is using his belief that God exists as a premise in his reasoning to prove something about the epistemic status of his belief.
But many epistemologists have come to be okay with such circular reasoning. (For example, Mike Bergmann would probably be okay with it so long as Smith had no significant doubts about God exists or it's not the case that he ought to have. And I don't think anybody's provided a good criticism of Bergmann's defense in the literature.)
Q1) Is Smith's reasoning okay? (granted my assumptions)
Q2) Anybody know of any literature that assesses the sort of reasoning Smith is engaging in (w/r/t theistic belief)?
[AUTHOR'S EDIT: MY FIRST COMMENT BELOW, IN RESPONSE TO THE NATES, MAKES IT MUCH MORE CLEAR WHY I THINK THAT THERE IS EPISTEMIC CIRCULARITY GOING ON. PLEASE READ THAT IF YOU PLAN ON RESPONDING TO THIS POST.]