This has come up before, and I've given a few short summaries in other threads, but it's come up often enough that I wanted to give a fuller description of my views on the matter, and put them up for discussion. A warning: this is pretty complicated, and my post won't be able to fully discuss everything. For those interested, a fuller account can be found
here, and in the book
Divine Providence: A Molinist Account by Thomas Flint.
So, God is absolutely free. He is not limited by power or by intelligence, the way humans are. So take the set of possible worlds. God can create any of these he wants, right? Not really. Molinists hold that there is a very important subset to the set of possible worlds: the set of feasible worlds. And it is this set that God chooses among when he creates. You see, God has a very special kind of knowledge, called middle knowledge. He not only knows what happened, what is happening, and what will happen, but he also knows what would have happened. Consider the case of Eric. One day, Eric is out walking, and he walks past the pet shop. God knows, of course, that Eric is walking and walked past the pet shop. God also knows, beforehand, that Eric will walk past the pet shop. But Molinism maintains that God also knows that, if Eric
had walked into the pet shop, Eric would have bought an iguana. More generally we can say that, for all cirumstances C, agents P, and actions A, God knows the truth or falsity of the claim "In C, P would have freely done A". These claims are called "Counterfactuals of Creaturely Freedom"
So what does this have to do with possible or feasible worlds? The feasible worlds are that set of worlds in which all of the actually true counterfactuals of creaturely freedom are true. Note, by the way, that this includes worlds in which C obtains and worlds in which C does not obtain. It includes worlds in which Eric walks into the pet shop and worlds in which Eric does not walk into the pet shop. But in all the feasible worlds in which Eric walks into the pet shop, Eric freely buys an iguana. So God simply chooses a feasible worlds to actualize, and all of the states of affair which obtain in that world, God either strongly actualizes (by, say, making the boiling point of water 100 degrees C) or weakly actualizes (by, say, creating the world in which Eric walks into the pet shop, so that he'll buy the iguana). That is to say, God has control because he has control over what the circumstances we're in are, and he knows what we will freely choose to do in those circumstances. But he doesn't make us choose either way, so we are still free -- whether or not Eric buys the iguana is up to him.
So, what do you think? Does this make sense to you?