Nudge: The final edition - Richard Thaler and Cass Sunstein ***

I've come late to this updated 'classic' popular psychology book from 2021, updating the 2008 original. If I'd read it when the first version came out, I would probably have been really positive about it. Much of what's in here sounds very sensible and effective. And all sorts of people followed the concept of 'nudging', from hotels telling us that most people reuse towels to reduce laundry costs to governments setting up 'nudge units' like the UK's Behavioural Insights Team. But the reality has proved rather different from the assertions made here.

One problem is sorting out what a nudge is. According to Richard Thaler and Cass Sunstein, a nudge should 'alter people's behaviour in a predictable way without forbidding any options or significantly changing their economic incentives.' Nudges should be both easy and cheap, making them 'libertarian paternalism'.

There is no doubt that some nudges work, some do something but not what is claimed, some don't work at all... and many never were nudges in the first place.

A classic pre-nudge nudge is painting broken white lines down the middle of the road. There is good evidence that this improved road safety in classic nudge fashion. Probably the poster child of nudge, opt-out organ donation fits in the second category. There is no doubt that it did increase sign up - but it didn't increase organ donation significantly because there wasn't the foundation of a good supply and match ability to back up those extra sign-ups. Thaler and Sunstein acknowledge the need to go beyond the nudge, here but fail to admit that this underlines the power of nudging in isolation is often limited.

A wonderful example of the 'never worked' type is the idea of having a rewards system to encourage recycling. We are told that 'in the Royal Borough of Windsor and Maidenhead, a London suburb' (I suspect the residents of Windsor and Maidenhead would have something to say about this description) recycling increased by 35% as a result of a reward scheme. But clearly the authors never followed this up, as it was abandoned years ago and academic reviews of these schemes found their effectiveness doubtful.

As for the 'not a nudge in the first place' category, quite of few of the examples given here are not nudges by the authors' own definition. For example a scheme they describe did result in a reduction of littering in Texas - but we are not told that this 'nudge' included an up-to-$2,000 fine, and a program of volunteer litter pick up days. The way the use of nudges is described, it appears that something is a nudge if it works and not if it doesn't.

Making things worse is the replication crisis in psychology and other soft sciences, which has rendered much the original research in this kind of field of doubtful value. The updated version of the book, despite coming well after the realisation than many social sciences studies were underpowered or had manipulated results that had little or no value, does not give us any sense of taking a step back from original assertions.

I was disappointed by this book - while I used to love its ilk (for example, Leavitt and Dubner's Freakonomics), I have come to be highly suspicious of the claims made in popular social sciences books which claim to give amazing and surprising insights into everyday behaviour that will change your life, your work and your government. So much for innocence of youth...

Paperback:   

Kindle:  

Using these links earns us commission at no cost to you

These articles will always be free - but if you'd like to support my online work, consider buying a virtual coffee:

Review by Brian Clegg - See all Brian's online articles or subscribe to a weekly email free here