The Modal Collapse Objection to Divine Simplicity

INTERVIEWER: The modal collapse objection to divine simplicity – the name alone is enough to make people a little bit afraid. But what is this objection, and then let's talk a little about that.

DR. MULLINS: Right. Okay, so let me say what a modal collapse is. Modality is about concepts like potential and actual, necessary and contingent, so those are different categories. When you have a modal collapse, it's when all of those get collapsed into a single category, so everything becomes necessary, or everything becomes contingent. And so what I've done in my own published work is I've articulated several different ways you could develop a modal collapse, where when you look at certain claims that Christians want to make about God's freedom, God's power, God's knowledge, and then you throw simplicity into the mix, then you get a modal collapse where everything becomes necessary. And that's bad because then nobody has freedom, not even God.

DR. CRAIG: I think there are a number of ways to result in modal collapse from the doctrine of divine simplicity. Here's just a couple of very simple ways to understand it. Everything that God knows, he knows essentially, according to the doctrine of simplicity. His knowledge is identical to himself, so he has no contingent knowledge. What that means is, since everything that God knows is true, that the same propositions are true in every possible world. In other words, there is only one possible world. So modal collapse results from God's knowledge being essential to him. Or the absence of potentiality in God. Since God is pure actuality with no potential, he has no potential to do anything else than what he is doing. Therefore there is no other possible world in which God does anything different, because if there were, then God has the potential to do it. So the absence of potentiality also leads to this sort of modal collapse. And what this results in is a sort of logical fatalism where everything that is or happens is and happens necessarily, which is absurd.