Is the nonbeliever at fault for rejecting God?
No, she is not at fault. Consider the following: 1. If one is adequately informed of the consequences of a decision, and willfully choosing to make that decision is clearly irrational, then it is irrational to willfully choose to make it.
2. If one willfully chooses to make an irrational decision, then one's moral or reasoning faculties are defective.
3. If one's moral or reasoning faculties are defective, then this defect was either the result of (a) choices that the agent herself made in the past or (b) external causes.
4. If one's moral or reasoning faculties are defective due to external causes, then it cannot be one's fault that one's reasoning faculties are defective.
5. If one's moral or reasoning faculties are defective due to choices that the agent herself has made in the past, then it cannot be one's fault that her reasoning faculties are defective.
6. If it cannot be one's fault that one's moral or reasoning faculties are defective, then it cannot be one's fault for willfully making an irrational decision.
7. Nonbelievers are adequately informed of the consequences of rejecting God, and willfully choosing to make that decision is clearly irrational. [ assumed only for the sake of argument ]
------------------------
8. Therefore, nonbelievers who willfully choose to reject God are irrational in choosing to make this decision. (from 6, 1)
9. Therefore, those nonbelievers' moral or reasoning faculties are defective. (from 7, 2)
10. Therefore, it cannot be the nonbelievers' fault that their moral or reasoning faculties are defective. (from 8, 5, 4, and 3)
11. Therefore, it cannot be the nonbelievers' fault for willfully choosing to reject God. (from 10, 8, and 6)
Some would question (5). Some, I suspect, are inclined to think that if one's moral or reasoning faculties are defective due to choices that the agent herself has made in the past, then it can be her fault that her moral or reasoning faculties are defective. Not so: we first have to inquire why the agent made the choices she did. Were they rational choices or irrational choices? Was she aware of the fact that her past choices would result in her moral or reasoning faculties becoming defective? If she was aware of this consequence, then her past choices could not have been rational -- hence they were irrational. But if willfully choosing to make those choices was irrational, then her moral or reasoning faculties were already defective.
At some point, after we have inquired into why the agent made the choices she did, we arrive at an external explanation. We thus arrive at conclusion (4): that if one's moral or reasoning faculties are defective due to external causes, then it cannot be one's fault that one's reasoning faculties are defective.
http://debunkingchristianity.blogspot.com/2009/07/is-nonbeliever-at-fault-for-rejecting.html