Although the phrases “Problem of Evil” and “Argument from Evil” are often used interchangeably, an important distinction needs to be made. The Problem of Evil is, at bottom, a question. “If God exists,” ask atheists and theists alike, “why is there so much suffering in the world?” Or, “If an all-powerful, all-knowing, wholly good being exists, how can evil be a part of any created order?” Or, “Why did God allow Grandma to get cancer?”
Notice that no positive claim is being made here. That is, the person asking the question is not really affirming or denying anything about God. This is significant, because when dealing with the Problem of Evil, skeptics frequently ask a series of questions without any argument whatsoever. “Why did God do X? Why did God do Y? Why does God allow Z?” The implication, of course, is that if theists cannot answer such questions, their position is somehow flawed.
But surely no atheist could consistently employ such a principle against theism. For, if we say that the ability to answer questions is a criterion for truth, the atheist will hardly get very far when we apply this method to atheism (e.g. when we ask where the universe came from, why it is finely tuned for life, how life formed, why there is so much evidence for the resurrection of Jesus, why moral values seem objective, etc.). In other words, questions aren’t enough. What we need are arguments.
This is where the Argument from Evil comes in. Here the atheist isn’t merely asking a question, but making a truth-claim and defending it with evidence. The difference is that, with an argument on the table, we are now in a position to judge whether the evidence really bears on theism. We can make sure that there are true premises and valid logic, and, therefore, that the conclusion actually follows. We can assign definitions to terms, and ask how the skeptic arrived at these definitions. We can test principles, and ensure that the atheist is applying these principles consistently.
A series of questions, however (which, again, is what we typically find atheists posing), is far more difficult to evaluate properly. It’s simply impossible to assess the evidential value of X in the question “Why did God allow X?”
Hence, we should be careful to ascertain when a question is being asked, and when a truth-claim is being made. The beginning of a dialogue, then, might go something like this:
ATHEIST: “Why did God allow the Holocaust?”
THEIST: “Are you trying to make an argument, or are you simply asking a question? If it is the latter, I might exercise a little restraint and say that I don’t know.”
ATHEIST: “No, I’m saying that the Holocaust is evidence against God’s existence.”
THEIST: “Well then, I’ll need to see an argument to that effect.”
ATHEIST: “Fine. If God is all-powerful, he would be able to prevent the Holocaust. If God is all-knowing, he would know how to prevent the Holocaust. If he is all-good, he would want to prevent the Holocaust. But the Holocaust happened. Hence, God does not exist.”
THEIST: “All right. Now we’ve got some premises to examine. . . .”
This would, of course, apply in the other direction as well. A different conversation might begin thus:
THEIST: “If God doesn’t exist, where did life come from?”
ATHEIST: “Well, if you’re only asking a question, I might reply that I don’t know. Or, were you trying to make an argument?”
THEIST: “I’m trying to make an argument. It goes like this. The complexity of even the most primitive life-form imaginable is mind-boggling. Chance is not a reasonable option, since the odds are so overwhelmingly against it. Hence, the best explanation would be some kind of intelligence.”
ATHEIST: “Now we’ve got something to work with. . . .”
The point of all this is that we must be careful to note the difference between (1) evidence against theism, and (2) interesting issues and puzzles for theists. The Argument from Evil, if successful, gives us evidence against theism. The Problem of Evil gives us only mysteries to think about.
Interestingly, from my experience, most of the people who leave Christianity don’t understand this distinction. I’ve heard several former Christians say something like, “Well, I just couldn’t figure out X, and my pastor couldn’t explain it to me. So I left Christianity and became an atheist.” Notice that the atheist here is saying that he left Christianity because of an unanswered question. But if unanswered questions are a problem, atheists have far more to be uncomfortable about than theists.