(1) If God exists he is omniscient, omnipotent, and wholly good.
[Hypothesis that the theists' God exists]
(2) Evil occurs.
[Statement of the undisputed fact of evil]
(3) If someone did not prevent the occurrence of evil despite having full knowledge in advance that it would occur if he were not to prevent it and despite also having unlimited power to prevent it, then that person is morally culpable for its occurrence.
[Generalized principle of command responsibility]
(4) By virtue of his omniscience, God knew in advance that evil would occur unless he was to prevent it.
[From 1 by definition of omniscience]
(5) By virtue of his omnipotence, God had the ability to prevent the occurrence of evil.
[From 1 by definition of omnipotence in terms of absence of nonlogical limits to God's ability]
(6) God did not prevent the occurrence of evil.
[From 2 by double negation]
(7) God had the ability to prevent evil from occurring and knew it would occur if he did not prevent it.
[From 4 and 5 by conjunction]
(8) God is morally culpable for the occurrence of evil.
[From the conjunction of 3, 6, and 7 by modus ponens]
(9) God is not wholly good.
[From 8 by definition of "wholly good"]
(10) God does not exist.
[From 1 and 9 by modus tollens]
7.4 Conclusion
The theist's God was supposed to be morally perfect as well as omnipotent and omniscient. But from the undisputed fact that evil exists in the world whose existence he supposedly brought about, it follows--by the unassailable moral truth expressed in the Generalized Principle of Command Responsibility--that he can't have all three properties at once. Ipso facto, such a God does not now, and never did, exist. It is the logic of the new Down-Under Disproof, not of Plantinga's Free Will Defense, that triumphs.
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