Christians are often confronted with the problem of evil. If God is all-good, then how can He allow evil things to happen? There are varied answers to the question, oft debated and discussed. However, how does the atheist answer the same problem from a naturalistic/materialistic perspective?
Firstly, the problem needs to be properly framed. And the first key question is whether evil, from a materialist sense, actually exists? If we deny the existence of evil, then we deny the need for any moral conduct, since morality at the very least describes acts of right and wrong, or, good and evil personified. The universal existence of moral code, varied as it may be, and a universal sense of how we ought to behave, exists without question. It may differ from society to society, but every society is morally governed in some sense. I think it is therefore safe to conclude that if determination of right from wrong exists, then good and evil does exist.
We can further justify the existence of evil by the universal condemnation of what is perceived to be evil acts. Genocide, theft, rape and imperialism, for example, are almost universally rejected, except by the perpetrators of course.
The second issue to be addressed then is if evil does indeed exist, then what is the nature of evil? Here we must be extremely careful not to confuse acts of evil and evil itself. Or put another way, is evil a cause or an effect?
If evil acts, as discussed above, are indeed the very nature of evil, then evil is an effect, but of what? For the atheist, there is but one answer, it is the effect of impersonal and random processes. But how can processes that are random and impersonal result in effects that are personal (moral indignation and suffering) and specific (groups or individuals affected). Furthermore, if all evil acts are the result of naturalistic processes, then on what grounds can the atheist condemn evil acts? It is surely just the inevitable outcome of what the laws of nature determined, and cannot be right or wrong if so determined. To summarize then, evil as an effect is a fatalistic outcome of predetermined laws, and as such, moral indignation is misplaced.
But I think it is somewhat shallow to argue that evil is equal to evil acts. The act of evil has to be caused by an underlying motive or force, human moral decisions are not as instinctive as the killing of prey by lions, for example. Something predetermines our moral reactions, whether it be societal norms or something in our genes. The fact is, evil acts are motivated by something else. What are the possible causes of evil acts? If evil itself exists separately from evil acts, as we surmised in the first paragraph, and it is not just evil acts, then it becomes the cause of evil acts. The atheist must then account for evil as a cause of evil acts, and the task becomes even harder. The very causes which are responsible for the progression of nature, including survival of the fittest, becomes the personification of evil. The removal of the weaker from the gene pool is generally viewed as morally wrong, yet this selection by nature is the backbone of progression in the atheist world view, and therefore, becomes the cause of evil.
In the end, we reach similar conclusions from both arguments. The atheist has an interesting conundrum. He can deny the existence of evil and its effects, but that would merely be sticking his head in the sand. Alternatively, he can acknowledge the effects of evil, and accept the fatalistic omnipotence of random existence as the cause. Again, this is somewhat unsatisfactory, since man can clearly avoid acts of evil, we all do it every day. Lastly, he can argue for an uncaused metaphysic of evil based on evolutionary development, where the metaphysic follows the selection of nature for survival. Again, this leads to conflicting arguments, survival of the fittest is by no means equal to normative moral behavior, and indeed stands mostly in direct contrast, unless the atheist wishes to argue that natural selection has a moral purpose.
Either way, the problem of evil is indeed problematic for atheists. The very causes which they propose to be responsible for our moral compass are irrevocably responsible for evil, either in cause or effect. Of course, they attempt to divert attention from this severe shortcoming by attacking Christian morality. However, the atheist philosophy must withstand internal criticism, and before the atheist can level criticism at other positions, he should account for his position, or else argue from midair.
For the Christian, evil is that which is in opposition to God, personified in Satan, the cause of evil acts. The love of God has overcome evil, so that we may stand justified before Him, the opposition forgiven.