Dogma will always lead to murder. In the end, scepticism is the only answer

The Woolwich killers were certain that faith supported their actions

Although defenders of religion like to portray faith as a source of peace and fellowship, and condemn those who commit atrocities in its name as untrue believers, the daily news media show how far this is from being invariably true. In fact, the relentless drip of bad news about religion-prompted violence in the world shows that the more zealous people are in their religious beliefs, the more likely they are to behave in non-rational, antisocial or violent ways.

The cold-blooded public murder of soldier Lee Rigby in Woolwich this week is an example. Murders are committed for a variety of reasons, but one thing they have in common is that those who commit them have to be in an abnormal state of mind. From rage or jealousy, through the cold psychopathology of the professional hitman, to the soldier who must be rigorously schooled and disciplined so that he can kill other human beings in defined circumstances, a difference to the normal mindset is required. One potent way of achieving the required mindset is religious zealotry.

Belief in supernatural beings, miracles and the fantastical tales told in ancient scriptures is, at least, irrational and, at worst, pathological. The more earnest the belief, therefore, the less sane is it likely to be in its application to the real world. At the extreme, it not only prompts but also – from their own perspective – justifies believers in what they do. Unnatural lifestyles, self-harm, ritualistic repetitive behaviours, fantasy beliefs and the like – all of them the norm for religiously committed folk – might be harmless to others in most cases, but when they become annexed to hostility to others outside the faith, or to apostates within it, the result is dangerous.

To the ordinarily sane mind, such acts as butchering a stranger in the street in broad daylight, and engineering a mass murder such as happened on 9/11, are in equal proportions lunatic and disgusting. Working backwards from that judgement, we must arrive at the conclusion that the people who do such things are neither ordinary nor sane. They exhibit a defining mark of psychopathology: the ability to proceed by perfectly rational steps from mad premises to horrible conclusions, while yet displaying in most of their surrounding behaviour the appearance of normality.

Consider: the 9/11 murderers engaged in a long period of flying training, planning, financing their activities and living among their victims – even queuing politely to get on the fatal planes with those they were about to kill – and all this takes self-control. But wedged into the outwardly normal behaviour, like a rusted medieval nail driven deep into their brains, was the lunatic belief that they were doing something meritorious, justified and moral.

“Faith,” someone once said, “is what I will die for; dogma is what I will kill for.” The border between preparedness to die and kill is so porous that it is easily crossed. As a result, history welters in the blood of religion-inspired mayhem. The problem is the complete and unshakeable assurance that religion gives its votaries that what they do in its name deserves praise. Agents of the Inquisition burned heretics to death to save them from the consequences of persisting in their sinfulness, so that they would spend less time in purgatory. So it was, they believed, an act of kindness to kill them. The current crop of terrorists do not bother to claim kindness towards their victims; hatred – or, at a poor best, revenge – is the frankly avowed motive. But here the justification is that unbelievers are worthless, deserving nothing but death.

It is a theme of recent critical attacks on religion that it is too often divisive, conflict-generating, atrocity-justifying and inflammatory – and this quite independently of whether any religious claims about supernatural beings or miraculous occurrences are true. Religious apologists are eager to point to the charitable and artistic outcomes of religion either as a palliation or an excuse, but non-religious people do charitable and artistic things, too, and it is hard to detach them from the kindness and creativity, respectively, that are a natural endowment of most human beings no matter what they believe.

In further defence of religion, its apologists haul out the weary canards about Hitler, Stalin and Mao as examples of secular committers of atrocity – the claim even being made that they did what they did in the cause of atheism as such. Apart from the fact that Hitler was not an atheist, the interesting point about ideologies that claim the One Great Truth and the One Right Way is that it does not matter whether it invokes gods or the dialectic of history as their justification; it is their monolithic and totalising character that does the work of making them murderous. The Inquisition of Torquemada and Stalinism are little different in their effects on their hapless victims.

The obvious point to note about the murders carried out in the name of a deity this week, whether Sunni car bomb attacks on Shia in Iraq or the murder of Lee Rigby, is that they were affairs of conviction. To do such things, you have to be convinced to the point of unreason that you are doing right. Note this contrast: in the careful estimations of a scientific world-view, nothing is so certain. The absence of question marks and their prompting of reflection, caution and the search for good evidence are not required when it comes to the eternal truths of faith.

Is there any way of combating the corrosive effects of unreasoning religious conviction that leads to so much murder in the world? Yes: stop making children think that they must implicitly accept and unquestioningly obey one or another supposed Great Truth. Encourage them to be sceptical, to ask for the reasons and the evidence, to see with a clear eye the consequences that might follow from believing an inherited picture of the world that wishes to be immune to challenge or revision, and is prepared to kill people who do challenge it.

Then, in a generation or two, what happened on a Woolwich street might become close to impossible.