Bits of Books - Books by Title


Everything Is Obvious *

* Once You Know the Answer

Duncan Watts



'Common sense' is the set of informal rules that we use to get through our day. But 'common sense' varies. Play the Ultimatum Game - Europeans invariably offer/refuse to accept anything but 50/50 split. A Peru tribe happy to accept anything - they have no concept of co-operation outside their immediate family. But some New Guinean tribes will not accept even an 80/20 split in their favour, because that would leave them with an unwanted obligation to reciprocate sometime in the future.

More books on Money

So 'common sense is common only if you belong to the same society.

In 1996, just 15 years ago, only 25% accepted same-sex marriage. For 75% it was common sense that it was wrong.But today, support is over 50%. This raises question - if our idea of what is obviously right is now wrong, what else is there that we today consider self-evident, but will change in the future.

We like to think that we have a consistent, coherent worldview, but in fact it is fragmented and ad hoc. Usually ok because daily life is essentially a series of small problems in very specific areas. But problems when try to use commonsense to deal with big, not-every-day problems. Such as anticipating or managing the behaviour of large groups of people with different cultural beliefs to yours (and so a different idea of what makes common sense.)

We try to understand and judge other groups, such as Israel/Palestine, Afghan etc, or issues such as finacial, health or education reform. But in none of these are we using 'common sense' to figure out how WE shd behave. Instead we try to use it to understand circumstances of which we have only the slightest understanding.

This doesn't matter when it's you and me round the kitchen table. But policy makers invariably rely on their own common sense to decide how to 'help' poor people for example. And it always fails, often spectacularly. UN aid to Africa has poured trillions down the plughole with virtually no improvement. Ditto US war on poverty.

3 types of errors we make in reasoning 1. when we think about why people act the way they do, we focus on incentives, motives, beliefs. Yet decades of research has shown that conscious decision making is just the tip of the iceberg.

2. groups think differently to individuals, in unexpected ways. We try to explain in terms of labels - 'the workers' 'influencers' to whom we attribute all agency. But this is as useful as savages calling thunder 'gods fighting'. The explanation satisfies them, but it is wrong and unhelpful.

3. We look for explanations but we only concentrate on the highlights - so we explain 9/11 by concentrating on the extremists, but we ignore all the other things happening around it.

Common sense very good at making senseof the world, but not necessarily at understanding it . Works just like mythology - a plausible sounding story which just papers over the gaps in our understanding.

Economists have spent decades trying to shoehorn market behaviour into mathematical models of rational behaviour. Yet countless expts have shown that we care as least as much about intangibles such as our reputation, belonging to a group and 'doing the right thing', as wealth and material possessions.

When someone does something you don't understand, rather than assuming they're crazy, you shd look closer.

But when we try to understand the other person's rationale we do it by trying to simulate what we wd do in the same circumstances. But we have only an incomplete picture of all the factors relevant to the other person.

Priming changes behaviour. Anchoring: give people two high numbers - say 86 - they'll bid higher for an item than if given two low numbers. Charities try to exploit this by offering you a range of amounts as suggested donations.

Our memory tricks us - we rem our past behaviour and beliefs to be more similar to our current behaviour and beliefs than they really were.

We are more likely to believe a written statement if it's in an easy to read font, or if have read it before, even though the first time you read it, it was explicitly labelled false.

We pay attention to info that confirms existing beliefs and are much more sceptical of info that contradicts - confirmation bias.

Economists are convinced that there isn't a problem that can't be fixed if given a free hand to devise an incentive system. Yet incentives just don't work, or have perverse effects. US tried to incentivise teacher. Led to outright cheating (altering answers), teaching to the test, and concentrating on marginal students who cd get over the line with a marginal improvement.

But even when the incentive clearly doesn't work, don't consider the possibility that yr 'common sense' might be wrong; you try another incentive.

New York Times Review

Books by Title

Books by Author

Books by Topic

Bits of Books To Impress