(P1) Carrie's murder was, in itself, a very bad thing.
(P2) If there was no sufficiently good point served by allowing this very bad thing to happen, then God, if he exists, would have prevented it.
(P3) There was no sufficiently good point served by allowing this very bad thing.
(C1) Therefore, if God exists, he would have prevented this thing from happening.
(P4) God did not prevent this thing from happening (since it did happen).
(C2) Therefore, God does not exist.
(p1) After careful reflection, we see no good point served by allowing this bad thing to occur.
(p2) If, after careful reflection, we see no sufficiently good point served by allowing some bad thing to occur, then we have some reason to believe there is no sufficiently good point served by allowing it to occur.
(c1) Therefore, we have some reason to believe there is no sufficiently good point served by allowing it to occur.
(p3) We have no outweighing reason to believe the contrary (that there is a sufficiently good point served by allowing this evil).
(p4) If we have some reason to believe some proposition, and no decent reasons to believe the contrary, then on balance, reason requires us to believe that proposition.
(c2) Therefore, reason requires us to believe that there is no sufficiently good point served by allowing this bad thing to occur.