The Science of Discworld IV Judgement Da - By Terry Pratchett, Ian Stewart Page 0,115
trumps an intuitive assessment that the location has ample building materials. Avoiding floodplains, even though it is easy to build houses on them and they are currently unoccupied, can prevent complete destruction of your property when the river rises. There is a reason why they are currently unoccupied.
Teasing out the workings of the human brain is tricky, but psychologists have developed techniques that help. In this case, participants were first interviewed to determine the extent of their religious beliefs. Sometime later, the main experiment was carried out, in two different ways. In the first, participants were given a randomly rearranged five-word phrase – such as ‘speak than louder words actions’ – and were asked to rearrange the words to make sense. Some of them were given scrambled phrases containing many words related to analytical thinking; the rest were not. After this exercise, they were asked whether they agreed that God exists. The group whose training period involved words related to analytical thinking were more likely to disagree. Moreover, this tendency remained, even when their prior beliefs were taken into account. The second version of the experiment relied on previous research, showing that asking people to read something printed in a hard-to-read font promoted analytical thinking, perhaps because they have to proceed more slowly and puzzle out the meaning of the letters. Subjects that completed a survey printed in a semi-illegible font were less likely to agree that God exists than those given the same material in a legible one.
The magazine article summed up the study: ‘It may help to explain why the vast majority of Americans tend to believe in God. Because System 2 thinking requires effort, most of us tend to rely on System 1 thinking processes whenever possible.’
There is a loose relationship between System 1/System 2 and Benford’s distinction between human-centred or universe-centred thinking. Intuitive thinking mainly takes a human-scale view of the world, and often places emphasis on quick decisions based on little more than hunches. Many people, finding it difficult to weigh up electoral candidates’ manifestos because political issues are often complicated, rely on instant judgements – System 1. ‘His eyes look too close together.’ ‘I like that smart suit he’s wearing.’ ‘Anyone who’s for/against a free market gets my vote.’ Universe-centred thinking is necessarily analytical, System 2. Humans have to train themselves to think inhuman thoughts. It takes conscious effort, and education, to reject a human-centred view.
Of course, there is no reason to suppose that these two ways of distinguishing thought processes have to match up, and they probably don’t, not in detail. Moreover, the psychological experiments only scratch the surface of human motivations and beliefs. Even if the conclusions are correct – and it is relatively easy to raise objections – they demonstrate an association, not a cause. But the results correspond to other observations of religious belief, for example that it is much rarer among scientists and well-educated people than it is among the poorly educated. And it is the common experience of atheists and rationalists that people who embrace extreme versions of religion tend not to be good at critical thinking. Especially about their own beliefs.
Psychologists study the whole human brain; neuroscientists look at the brain’s detailed workings, in particular how it controls the movements of the body. Many think that this is why the brain evolved to begin with, and sensory information-processing came later, along with all of the other subtler functions of the brain. Engineers, aiming to build better robots, are borrowing tricks from the brain. One of the fundamental features of the brain is how it deals with uncertainty.
Our senses are imprecise, and their inputs to the brain are subject to ‘noise’ – random mistakes. The workings of the brain, being evolved wetware (the organic material of the nervous system) rather than carefully engineered hardware or software, are also subject to errors. The signals that the brain sends to the body suffer from unavoidable variability. Try to sink a golf ball with a ten-metre putt, a hundred times. You won’t get it in the hole every time. Sometimes you may succeed, sometimes you’ll miss by a small amount, but occasionally you’ll miss by more. Professional golfers are paid a lot of money because they are marginally better at reducing this kind of variability than the rest of us.
The same variability comes into play, usually in a more exaggerated form, when it comes to social and political judgements. Here the noise-to-signal ratio is even higher. Not only do we need