The most common argument that God does not exist proceeds from the existence of evil.
1) God is omniscient.
2) So God knows if evil exists.
3) God is omnibenevolent.
4) So God desires good.
5) God is omnipotent.
6) So God can eliminate evil.
7) There is no evil.
Since if there were evil God would know about it, would desire to eliminate it, and could eliminate it.
8) However, we see there is evil.
9) Therefor there is no being that knows about evil, desires it to be eliminated, and can eliminate evil; ie, there's no being that is omniscient, omnipotent, and omnibenevolent; ie, there is no God.
Below I will discuss a version of the problem that I think is particularly tough.
Apologetics is the field of theology and philosophy of religion that seeks to "apologize" for God's failure to eliminate evil from the world and other criticisms of religion. That is, apologetics seeks to explain how the existence of evil could in fact be consistent with the "tri-omni" God of the Western philosophical tradition.
One solution is to say that God exists but reject the tri-omni conception. Fundamentalists do this, embracing the Bible or other religious text as a literal story, in which God is not omnibenevolent at all, but instead has many qualities of human moral frailty such as jealousy, fits of rage, and even--in the Abrahamic tradition--favoritism of specific tribes over others, even ordering the Israelites to commit genocide against the Midianites, a tribe descended from one of Abraham's sons that inhabitted (roughly) the Gaza Strip.
Most reasonable people reject that kind of fundamentalism in favor of more nuanced and metaphorical readings of (eg) God's relationship to the Israelite's history, and a rich tradition of thought about social justice can frequently spring from the very same stories and texts that fundamentalists misunderstand. This is true of Islam, Christianity, and Judaism alike. For these more liberal interpretive traditions to flourish as something more than literary criticism of mythologies (as foundations for religion in a rational and secular society) a rich philosophical concept of God is necessary to replace the anthropomorphic deity of cruder traditions.
A major apologetic against the Problem of Evil invokes human free will. Basically, the apology objects that God sees a higher good in creating moral creatures and that this requires a capacity for moral choice. Since we can choose, we can choose evil. We and not God are responsible for evil. There are several lines one might take against this argument. First, the concept of "free will" has been notoriously difficult to clearly explicate. It's one of those things that you think you have an understanding of until you start trying to say what exactly you mean. Maybe "free will" is a term without any sense. Even if we can make sense of free will, it is not immediately clear that God could not have created us so that we can and do choose good, or that maybe he could have just created us so that we can and do choose good more often than humans do. Furthermore, what about natural evil, like tsunamis and hurricanes.
These are all interesting lines of inquiry that have been explored in relative depth. To a certain extent, apologists have answers that might be satisfying for lots of people to each of these objections. I pose a new formulation of the problem of evil that I think creates special difficulty for the apologist.
People do evil thinking that they are doing God's Will.
It's important to note that I don't think that this is necessarily the only reason anyone does evil. Rather, I think that it is one source of evil and that if God existed then this kind of evil would not exist. The cause of this evil is not a failure of some humans to choose the good. They are sincerely seeking to do good by choosing to do what they believe is God's Will. The problem is that they don't know God's Will. In the jargon of religious folks, it's a failure of discernment. Some of those that do evil thinking that it is God's Will even sincerely seek to know God's will. The blame for this failure of discernment lies squarely with God, should God exist; in fact, evil of this type shows that God does not exist.
The free will defense cannot resolve this. The problem isn't with choices, but that choices are made on the basis of insufficient information. An omnipotent, omnibenevolent being could resolve information deficits with respect to His Will without taking a way freedom of choice as such. One more refuge of apology might be the "mysterious ways" defense. Maybe God has a good reason for failing to meet sincere requests for discernment and I just can't think of it because I am a measely wretch and incapable of comprehending His Infinite Will. I don't find that particularly interesting or convincing.
Of course, I'm aware of my own fallibility and limitted imagination and am open to hearing what reasons God might have for allowing failures of discernment, but the mere possibility of being wrong is not a defeater for rational belief in the validity of an argument. We rarely have certain proof of much of anything. That doesn't mean that we don't have knowledge. Just because I sometimes make simple errors, like forgetting to carry the one, I don't stop trusting my ability to do arithmetic altogether, and I certainly don't say that any method of calculating sums (including wild guesses) is just as good as the next. You need to show me or I need to see where I forgot to carry the one (eg). Pointing out that God might have a reason but not saying what it might be is like saying that I might have made an error in arithmetic but not showing me any error.
In other words: I'll believe in God when he gets his various fan clubs in order. With the recent violence between various and sundry fan clubs, there's been an unusual eruption of religious talk here at Kos. "A Free Man's Worship" by Bertrand Russell is a nice place to start if you are trying to make sense of yourself and the world you live in without the mythical crutches that cause and exascerbate so much strife.
Crossposted: http://ifthenknots.typepad.com/...