1. Two puzzles about omnipotence
Michael Lacewing
© Michael Lacewing

2. Omnipotence Omni-: all; potent: powerful
But is omnipotence the power to do everything?
What about the logically impossible?
Could God make = 5?

3. Omnipotence
Aquinas: no. What is impossible is a contradiction in terms
The words that you use to describe the impossible literally contradict each other
So any description of a logically impossible state of affairs or power is not meaningful
So what is logically impossible is not anything at all.
This is no limitation on God’s power – there is still nothing that God can’t do.

4. Omnipotence and supreme goodness
To commit evil is to fail to be supremely good.
If God is supremely good, then God cannot commit evil.
Therefore, if God is supremely good, there is something that God cannot do.
Therefore, God cannot be both supremely good and omnipotent.

5. Three solutions
God can commit evil (omnipotence), but always chooses not to (goodness).
There is no distinct power of ‘committing evil’ because ‘evil’ is not a type of act
God has all the powers to do the act which would be evil, but chooses not to.

6. Three solutions
Aquinas: there is no distinct power of ‘committing evil’ because ‘evil’ is simply the absence of good
Being ‘able’ to fail is not a power, but a lack of power to succeed
God does not lack the power to do good, so God cannot commit evil.

7. The paradox of the stone
Can God create a stone so heavy that he can’t lift it?
If yes, he can’t lift it; if no, he can’t create it.
Mavrodes: ‘The power to create a stone an omnipotent being can’t lift’ is logically incoherent, so it’s not a possible power
The fact that God can’t create a stone that God can’t lift does not mean that God lacks any power.

8. Savage on the paradox of the stone
Savage: Mavrodes’ solution begs the question
In talking of ‘a stone that an omnipotent being cannot lift’, it assumes that the concept of an omnipotent being is coherent
But that is just what is at issue.

9. Savage’s argument
Either x can create a stone which x cannot lift, or x cannot create a stone which x cannot lift.
If x can create a stone which x cannot lift, then, necessarily, there is at least one task which x cannot perform (namely, lift the stone in question).
If x cannot create a stone which x cannot lift, then, necessarily, there is at least one task which x cannot perform (namely, create the stone in question).

10. Savage’s argument
Hence, there is at least one task which x cannot perform.
If x is an omnipotent being, then x can perform any task.
Therefore, x is not omnipotent.
The concept of an omnipotent being is self-contradictory.

11. Agreed solution
Mavrodes offers a second solution: there is no limit on God’s power of lifting stones, so there is, in fact, no limit on God’s power of creating stones.
Savage agrees: ‘God cannot create a stone which God cannot lift’ only means that ‘if God can create a stone, then God can lift it’
God can create a stone of any size and then lift it – no limitation.