“Now if the basic moral principles are analytic, the existence of what they describe cannot provide an argument for the existence of God.  An argument could only take off from the truth of some or all synthetic moral truths (e.g., from the fact that it is wrong to drop atomb bombs on Japan rather than from the fact that it is wrong to kill people who will not certainly come to life again).  Now the fact that certain moral truths hold can only confirm, add to the probability of, the existence of God if it is more likely that those moral truths hold if there is a God than if there is not.  Now the synthetic truths that actions, a, b, c, d, are obligatory (or right or wrong as the case may be) depend on a, b, c, d, possessing certain natural properties Q, R, S, T, which analytically make them obligatory (or whatever).  So if there is to be an argument to the existence of God from certain actions being obligatory it will have a structure somewhat as follows: actions a, b, c, d, are obligatory; they would not be obligatory unless they were Q, R, S, T.  It is more probable that there are actions which are Q, R, S, T, if there is a God than if there is not; therefore the obligatoriness of a, b, c, d, confirms the existence of God.”

Richard Swinburne, The Existence of God, pp. 177-178.

Thus, according to Swinburne, analytic moral principles cannot provide an argument for the existence of God.  And an argument from synthentic moral truths to the existence of God would have to look like this in general form:

(1)   Action a is obligatory.

(2)   Action a would not be obligatory unless it possesses natural properties Q, R, S, T.

(3)   It is more probable that there are actions which have natural properties Q, R, S, T if there is a God than if there is not.

(4)   Therefore, the obligatoriness of a confirms the existence of God.

Now consider Craig’s argument that if atheism is true there would be nothing with rape.  As Swinburne argues, fundamental moral principles must be analytic.  And, surely, if any moral principle is analytic, the principle, ‘rape is wrong,’ is analytic.  Thus, the wrongness of rape cannot provide an argument for the existence of God.  But can a synthetic moral truth concerning rape provide an argument to the existence of God?

Let action:

a  =df. Ted Bundy’s rape of an innocent woman

Let natural properties:

Q =df. rape violates the desires of its victim;

R  =df. rape causes suffering; and

S  =df.  rape degrades the victim.

According to Swinburne, here is how an argument from the objective wrongness to the existence of God would have to proceed:

(1)   Ted Bundy’s rape of an innocent woman is objectively wrong.

(2)   Ted Bundy’s rape of an innocent woman would not be objectively wrong unless it violated the desires of his victim, caused her suffering, and degraded her.

(3)   It is more probable that there are actions which violate the desires of victims, cause suffering, and degrade victims if there is a God than if there is not.

(4)   Therefore, the objective wrongness of Ted Bundy’s rape of an innocent woman confirms the existence of God.

If this is fair example of the kind of argument Swinburne was describing–and I am not completely sure that it is–this example strikes me as a very odd argument for God’s existence. Re-read what (3) says. It is equivalent to the conjunction of :

(3.1) It is more probable that there are actions which violate the desires of victims if there is a God than if there is not;

(3.2) It is more probable that there are actions which cause suffering if there is a God than if there is not; and

(3.3) It is more probable that there are actions which degrade victims if there is a God than if there is not.

All of these strike me as bizarre, counterintuitive ‘predictions’ of theism, to say the least. If this is (were?) the only way to get a ‘good’ moral argument for God’s existence, then the prospects for such an argument (would?) look dim.