By Anthony Booth, University of Sussex

Every time we are shocked by a new terrorist atrocity, or when a surge in hate crimes takes hold in a country, we lament the malign grip of extremism. But what exactly do we mean when we say that someone holds extreme beliefs? And what exactly is wrong with extreme beliefs? Frankly, there has been little work in western philosophy to tackle these questions. Luckily, however, we can look to the work of a medieval Islamic philosopher – Abu Nasr al-Farabi – to help us find some answers.

Let’s consider two possible models for conceptualising extreme belief. One we might call the “defective belief model” which has become the tacit consensus view of the contemporary West. The other is the “over-belief model” favoured by al-Farabi, one of the great figures of the Islamic golden age of medieval philosophy, who lived in Baghdad in the 9th and 10th centuries. Al-Farabi is well known for his contributions to logic – his contemporaries gave him the moniker “the Second Master”, suggesting that only Aristotle surpassed his logical prowess. In Europe, he was better known as Alfarabius.

I want to make some conceptual points against the Western model of extremism and some in favour of al-Farabi’s.

Let’s begin by taking a look at the idea of defective belief. Under a version of this model, someone has extremist beliefs when they believe propositions that are morally bad to believe, such as that racism is permissible, or that it is permissible to target non-combatants during war.

Bad believer

The trouble with this view is that we do not have the same sort of control over our beliefs that we do over our actions. Suppose that someone offered to give you a million pounds to raise your right arm right now (assuming you have one). Try to do it. You can. But now suppose that someone made you the same offer to believe that you are a giant grasshopper. Try to believe it. You can’t.

But then it seems that there are no morally defective beliefs. This is because we can only be held to moral account for things that are under our control. For example, it seems crazy for me to blame you, the individual reader, for the last monsoon rains in India, given that their happening was something you could not control.

We might then make the following modification (staying within the model): what is defective about extremism isn’t to do with morality, but rather to do with extremists’ beliefs being grossly at odds with our evidence. We might then think that someone who does not believe in climate change, or who believes that Earth is flat is as much of an extremist as someone who believes that non-combatants are legitimate targets during war.

But the problem is that if extremist beliefs are just beliefs that are badly out of kilter with the evidence, then what, precisely, is extremist about them? If I was entirely convinced that I had fed the cat this morning, against the evidence provided by a full tin of cat food and a furious animal, does that make me an extremist? I think it doesn’t.

Further, there is the issue as to determining what is the available evidence. Some people may have what we think of as extreme views but only for want of access to key evidence (perhaps they’ve been brainwashed, or “radicalised” by the witholding of access to that evidence). Their views, may be well in accord with the evidence that is available to them, but does that stop us from identifying their views as those of an extremist?

Question of degrees

So what about that “over-belief” model? Suppose that beliefs can come in degrees: that someone can have a stronger belief that Manchester United will stay in the Premier League next season than that they will win it. Following Baysian mathematics, we can assign a range of values from say 0.1 to 1.0 to attempt to model the various degrees of belief. I might then have a 0.8 degree of belief that Manchester will avoid relegation, but only a 0.6 degree of belief that they will win it. The question is what constitutes “full” belief?

A tempting answer is that it is absolute certainty – 1.0. According to the over-belief model of extremism, however, it is more like 0.8. Anything above that is, other than in very unusual circumstances, to have too much credence in one’s belief. Put differently, we should nearly always allow for at least some small possibility that we might be mistaken – absolute certainty is almost always problematic relative to our evidence. To believe with absolute certainty, such that nothing could persuade us otherwise – to over believe – is to have extreme belief.

This way of thinking about it circumvents the problem of attaching moral responsibility to our beliefs. Extreme beliefs are held to be problematic relative to the evidence – and not to some moral standard. It also identifies something distinctive that all extremists’ beliefs possess, and so differentiates them from non-extremist beliefs which only rub up against the available evidence.

Something at least approximating this view can be found in the writings of al-Farabi. In one essay he identifies an intermediate state of knowledge between full certainty and a sort of sceptical nihilism. And he argues that as only the Prophet is in a position where he can attain full certainty, the rest of us mortals will need to learn to live with a less perfect state of knowledge.

Al-Farabi was well known for his contributions to logic, but he was also very well known, especially in the Islamic World, for his work in political philosophy – connecting philosophical problems with practical ideas. The Al-Farabi Kazakh National University in Kazakhstan, for example, recently instituted a project designed to use al-Farabi’s teachings on the ideal city-state as a blueprint for governance of the University. His teaching carries with it a lot of sway in the politics of the contemporary Islamic word – especially given the special status the Islamic world accords to the Medieval golden age of Islam.

And for al-Farabi, to believe with absolute certainty is to present oneself as possessing a state of knowledge available only to prophets and to God. To be an extremist is then to espouse idolatry, and, even, polytheism. And according to prophecy, of course, one of Muhammed’s central vocations was to cleanse Mecca (and the world) from these shirk idols.

Anthony Booth, Senior Lecturer in Philosophy , University of Sussex

This article was originally published on The Conversation. Read the original article.