Brian Carney has this article in the WSJ with the above title, subtitled, "Prison psychiatrist Theodore Dalrymple asks why we feel compelled to understand monsters like Anders Breivik, but no need to explain others' righteous behavior." The whole article is well worth reading, but here is an excerpt (emphasis added):
Your garden-variety convicts, he contends, are much simpler subjects than a man like Breivik. To ask them why they steal, he says, "is like asking you why you have lunch." They want something, so they take it. "And since in Britain," he adds with a smirk, "the state does very little to discourage [thieves]," or to incarcerate them when they are caught, "the question is not why there are so many burglars, but why there are so few."
A Breivik is a deeper mystery. Of him, "you can say, 'This man is highly narcissistic, paranoid and grandiose,'" and this may lead you to seek reasons for that in his past--"his father disappeared at the age of 15 and so on and so forth." But uncovering such facts doesn't solve the mystery because "whatever you find, you would also find among hundreds or thousands or even millions of people who didn't do what he did." There is, he says, "always a gap between what is to be explained and your alleged explanation. So there's always a mystery, and I think that's going to remain."
The human impulse to explain the inexplicably horrific is revealing, according to Dr. Dalrymple, in two respects--one personal, one political. First, it says something about us that we feel compelled to explain evil in a way that we don't feel about people's good actions. The discrepancy arises, he says, "because [Jean-Jacques] Rousseau has triumphed," by which he means that "we believe ourselves to be good, and that evil, or bad, is the deviation from what is natural."
For most of human history, the prevailing view was different. Our intrinsic nature was something to be overcome, restrained and civilized. But Rousseau's view, famously, was that society corrupted man's pristine nature. This is not only wrong, Dr. Dalrymple argues, but it has had profound and baleful effects on society and our attitude toward crime and punishment. For one thing, it has alienated us from responsibility for our own actions. For another, it has reduced our willingness to hold others responsible for theirs.