Usually the problem of evil is a problem for those who believe in a good and powerful God, but Marilyn McCord Adams thinks it's also a challenge for optimistic and idealistic atheists -- she makes an argument that is analogous to Kant's argument for immortality* in this past podcast from Philosophy Bites .....
[the problem of evil] is also a problem for unbelievers because the world is riddled with what I've called horrendous evils -- they're not a rare thing. it's easy to become a participant in them, and thousands, millions of people are participating in them now even as we speak. And so, what I want to say to people who don't believe in God is this: if you're optimistic and idealistic, if you think life is worth living and you have high purposes in your life, this is not a rational posture unless you think there is some super-human power who is capable of making good on the many and various horrors that human beings perpetrate every day on one another .... if you really open your eyes and see how riddled with horrors the world we live in is, and you still find yourself deeply optimistic and idealistic, then a condition of the possibility of your posture in life being reasonable is a belief in a God who is good enough and resourceful enough to make good on it all.
The guys at Philosophy Bites didn't seem to buy this argument, and I agree it's not compelling. But still I do wonder how it's possible for caring people to be aware of how very badly things are going for so many and yet to feel positively about life.
* In the Critique of Practical Reason, Kant argued that this Highest Good for Humanity is complete moral virtue together with complete happiness, the former being the condition of our deserving the latter. Unfortunately, Kant noted, virtue does not insure wellbeing and may even conflict with it. Further, there is no real possibility of moral perfection in this life and indeed few of us fully deserve the happiness we are lucky enough to enjoy. Reason cannot prove or disprove the existence of Divine Providence, nor the immortality of the soul, which seem necessary to rectify these things. Nevertheless, Kant argued, an unlimited amount of time to perfect ourselves (immortality) and a commensurate achievement of wellbeing (insured by God) are “postulates” required by reason when employed in moral matters. -- Kant's Moral Philosophy
