This is the the thirty-third post in my Theories of Knowledge and Reality series. Follow the link for more on the series and for links to other entries as they appear. In the last post, I finished up the final post on the problem of evil. This post begins what I expect to be a four-part series on philosophical theology.
[Note: The next few posts on philosophical theology are derived in part from discussions in Gregory E. Ganssle, Thinking About God (2004) InterVarsity Press.]
Philosophical theology is just philosopher-speak for thinking about what God might be like if God exists. Three philosophically important features traditionally have been omnipotence, omniscience, and complete goodness, and some interesting issues come up in the Ganssle book related to these three. The issue I'm dealing with in this post has come up before in relation to the problem of evil, but I thought it was worth a more extended discussion in light of its relevance for the issues that I think are much more interesting that will come in the next few posts.
The puzzle is sometimes given about whether God could make a rock so big that God could not move it. If omnipotence is the ability to do anything, then it seems God could. But then there would be a rock that God could not move, and that could never be true if God is omnipotent. So God must be unable to make such a rock. But then there is a limit to God’s ability, and does that mean God is not omnipotent? So either way God is not omnipotent. If God can make the rock, then God is not omnipotent. If God cannot make the rock, then God is not omnipotent.
The most common solution to the puzzle is to reexamine the definition of omnipotence. Some people consider omnipotence to be the ability to do anything. Most theists do not agree. They prefer to think of it as the ability to do anything possible. Maybe we can call the ability to do anything by the term ‘super-omnipotence’. But omnipotence itself is just the ability to do anything possible, not the ability to do anything you can put words to. You can put words to the action of making a rock God cannot move, but that does not mean such an action is possible. Some things are not possible. An omnipotent being could not make a square circle, could not make 2+2 be 5, and could not make something both red and not red at the same time in the same way. These are logical and mathematical limits. The actions so described are not real actions, since they are not possible in any sense. So it is not a big limit on God to say that God cannot do things that are not real actions to begin with.
So God is not super-omnipotent, since such a description leads to incoherence. But that does not mean that omnipotence is impossible. There could still be an omnipotent being even if super-omnipotence leads to contradictions.
I should mention the minority position. One famous philosopher, Rene Descartes, did at least at one point think that God is super-omnipotent. He said that God could make square circles. God could make a rock too big even for God to move. Of course, God could then move it. If God can make contradictions true, why couldn’t God move a rock too big even for an omnipotent being to move? Some medieval Christian philosophers attributed a similar position to some of the medieval Islamic philosophers, who said that God is above reason in some sense, and thus reason (and therefore logic) does not control God. I am not 100% sure that these philosophers held this position, but some of the philosophers in the middle ages did take some of them to be saying these things.
Next: Omniscience and Time