What makes a counterfactual true?
A counterfactual is a conditional proposition. For example, "If Shi goes to Jason's house, then she will kiss him." In an earlier blog, I was explaining how Plantinga showed that there are possible worlds an omnipotent God can't create. After writing it, I got to thinking about it some more. Remember that by the law of excluded middle, one of the following two propositions is true:
1. If Shi goes to Jason's house, then she will kiss him.
2. If Shi goes to Jason's house, then she will not kiss him.
Since one of those is true, there are possible worlds God can't actualize. If (1) is true, for example, then God can't actualize any possible world in which Shi goes to Jason's house and does not kiss him.
I got to thinking that the only reason one of these counterfactuals is true, and not the other, is because of which world God chooses to actualize. If God chooses to actualize a world in which Shi goes to Jason's house and kisses him, then (1) is true. If so, then it's up to God which counterfactual is true, and if it's up to God which counterfactual is true, then Plantinga's argument is faulty. God can actualize any possible world he wants to.
After thinking about this for a while, I discovered the error of my ways. You see, Plantinga is assuming libertarian free will. Shi is free to choose whether she is going to kiss Jason or not. That's one of the stipulations of Plantinga's argument. If Shi is free to choose, then it's Shi who determines which counterfactual is true, not God. The only way God can make one counterfactual true and not the other is by elminating Shi's free will. If God determines what Shi's choice will be, then Shi isn't really free. So Plantinga's argument is valid after all.