Decent people have sought to identify the roots of evil since the first indecent person inflicted cruelty on an innocent person. And people have come up with one or more of nine explanations, most of which are indeed valid.
1. The Devil (or whatever name the devil goes by in any given culture). I do not believe in a devil, but when one observes the seemingly inexplicable cruelty engaged in by some people, it is understandable that people have attributed it to some evil being that has taken over that person.
2. Genes. The contemporary term for devil is "genes." Just as with the devil, when we observe a person engaging in evil behavior for which we have no rational explanation, we speak of it as coming from the person's genes.
3. Parents. After genes, parents have become another popular explanation for much evil. "How was he raised?" we wonder when we read about evildoers, especially those who deliberately hurt children. There is no question that parental upbringing has both good and ill effects on children. But there are too many bad people raised in homes that did not abuse them, and too many good people who were raised in awful homes to allow us to make parents the primary explanation for evil.
4. Religion. Religion is a popular culprit these days. And it is undeniable that religion can be a source of evil it certainly is in the case of the true believing Islamic terrorist. And it was in the wars over theology that racked Europe for centuries. But two facts mitigate against regarding religion as the primary explanation for evil. One is that religion itself was often developed precisely in order to reduce human evil. Whatever evil individual Christians may have ever engaged in, it is hard to find advocacy of evil within Christian Scriptures. The other is that secular ideologies and regimes Nazism and Communism, for example have murdered and tortured far more people than any religion has.
5. Money. Money and greed are so widely regarded as causes of evil that the phrase "Money is the root of all evil" has become a cliche. And there is no doubt that people seeking what money can buy luxury, status, women and excitement, to name but a few things have engaged in much evil. But flawed human nature and a lack of self-control, not money per se, are the causes of evil in these instances.
6. Power. Like money, many who seek power will do anything, no matter how evil, to attain power. However, it is a relatively small number of people that seeks such power and commits evil in its pursuit.
7. Pursuit of the good. The road to hell is indeed paved with good intentions. One should never underestimate the amount of evil caused by people thinking they were doing good. Far more evil has been perpetrated by idealistic people than by cynical criminals.
8. Sadism. There are people who simply enjoy seeing others in pain and inflicting it on them. But sadism accounts for few, if any, large-scale evils. It accounts for many individual acts of cruelty.
9. Boredom. Boredom is widely underrated as a source of evil. Yet, it most certainly is. Lack of purpose, not a lack of things to do, is the source of nearly all boredom. People need meaning in their lives. And if they don't, they will pursue visceral excitement instead of meaning or seek meaning in evil causes.
I believe there is a tenth explanation that is greater than all the others and is particularly widespread today.
10. Victimhood. A lifelong study of good and evil has led to me conclude that the greatest single cause of evil is people perceiving of themselves or their group as victims. Nazism arose from Germans' sense of victimhood as a result of the Versailles Treaty, of the "stab in the back" that led to Germany's loss in World War I and of a world Jewish conspiracy. Communism was predicated on workers regarding themselves as victims of the bourgeoisie. Much of Islamic evil today emanates from a belief that the Muslim world has been victimized by Christians and Jews. Many prisoners, including those imprisoned for horrible crimes, regard themselves as victims of society or of their upbringing. The list of those attributing their evil acts to their being victims is as long as the list of evildoers.
This is also true in the micro realm. Family members whose primary identity is that of victim usually feel entirely free to hurt others in the family. That is why psychotherapists who regularly reinforce the victim status of their patients do the patient and society great harm.
If my belief is even partially correct, the preoccupation of much of America with telling whole groups that they are victims of racism, sexism, homophobia, xenophobia and classism, among other American sins can only increase cruelty and evil in America.