The Problem of Evil - Common Sense Atheism

The Idea of God 23
impossible. It is as impossible as a thing can be. In no possible world
does such a procedure exist. But logic alone does not suffice to establish
its impossibility, and, if the logically possible comprises everything that
is not logically impossible, it is therefore ‘‘logically possible’’. That is to
say, logical possibility is not a species of possibility. I must not spend
anymoretimeonthishobbyhorseofmine. 4 Suppose it is granted that
my scruples in the matter of logical possibility are well-founded. Might
we not accommodate them simply by saying that omnipotence is the
power to do anything that is metaphysically possible? We might indeed.
But if we did, we should still face the second of the two difficulties I
mentioned, and that difficulty is not at all controversial. It is this: most
theists contend that there are metaphysically possible acts that God is
unable to perform. Two well-known examples are lying and promise
breaking. Unlike trisecting the angle, lying and promise breaking are
certainly metaphysically possible things. (I don’t know about you, but
I’ve actually seen them done.) But, it’s commonly said, God is unable
to do either of these things because, although someone’s doing them is
metaphysically possible, his doing them is metaphysically impossible.
Let’s suppose that the philosophers and theologians who say that it is
metaphysically impossible for God to lie and to break his promises are
right. Does it follow from their thesis that God is not omnipotent?
According to the proposed definition, yes. But the way the case has
been described immediately suggests another definition, a definition one
frequently sees in works of philosophical theology, a definition designed
to meet exactly the difficulty we have been considering: to say that God
is omnipotent means that he can do anything such that his doing that
thing is metaphysically possible.
This definition meets the two difficulties I have mentioned, but it
has problems of its own. The most important of them is this: it doesn’t
tell us what God can do. Another way to put essentially the same point
would be to say that, at least as far as any human being is able to judge,
there might be two beings each of which was able to do everything
it was metaphysically possible for it to do and which were yet such
that one of them was vastly more powerful than the other. Suppose,
for example, that God exists, that he is able to do everything that it is
metaphysically possible for him to do, and that among the things that
it is metaphysically possible for him to do is to create things ex nihilo.
Suppose further that God creates a being, Demiourgos, who, although
he is very powerful by human standards, is unable to do many of the
things God can do. He is, for example, unable to create things ex nihilo.