Here's Martin Bell in today's Times (£):
How could the apparently affable old man sitting before me be responsible for such terrible atrocities? That was the question I asked myself last December as I sat with Radovan Karadzic, the former leader of the Bosnian Serb statelet, in his prison cell in The Hague.
Now the question arises again. How could Ratko Mladic, who came across as bluff and genial, be responsible for the worst war crime in Europe since 1945? The answer is that anyone is capable of anything...
This answer is given so often and with such ease that you might take it for an established truth. But in fact it is an ungrounded calumny against a significant proportion of the human race. I know I've had my say more than once rebutting it here, but coming across it for the nth time, from Martin Bell, I've thought of a way of showing - by scientific principles, no less - that it is indeed unproven and a calumny. How this occurred to me is as follows.
I thought... Although it's true that many people, put in circumstances which license or encourage the violation of others, will go ahead and violate them, a significant proportion - to repeat the phrase above - will not. But exactly what proportion is this (someone might ask)? Of course I don't know. And precisely not knowing leads me to the next step. I don't know in the same way that those who allege the universal potential for grave evil-doing don't know. They just make their generalization on a hunch. My scepticism towards the generalization is based on more than a hunch, however. It is based on the evidence from daily life that some people are more influenced by moral constraints than others are; and it is based on the very studies which show how many people will participate in the gravest of violations against others when circumstances are conducive to their doing so - because these studies also show that some people won't participate. It could be counter-argued that, aha, but those people haven't yet met what would be the apt circumstances for them, and there must be some. Yet this is a mere speculation. The evidence we have indicates that some people behave better than others in every circumstance - yes, even in the death camps. So there are no grounds (yet) to maintain that 'anyone is capable of anything' in the moral sense.
As for how an affable- or genial-seeming individual could be involved in mass murder, this strikes me as no more puzzling than that a human personality, any human personality, is made up of more facets than one. That there can be a charming killer, or a torturer who is a good family man, you had better believe. But that all the countless people who lead relatively virtuous lives would be ready to inflict the vilest horrors on others - this claim traduces the moral character of at least some of our human number. We need to to be aware not only that there are killers about but also that not everybody is one.