Tim Harford: What nudge theory got wrong

Is behavioural science unwittingly damaging society? Behavioural scientists have a dangerous habit of diagnosing problems in the same way. However, many fail to realise that most societal issues are systemic, not individual, and therefore nudges, at best, are ineffective. Tim Harford looks at Richard Thaler and Cass Sunstein's 2008 bestseller Nudge to break down the positives and negatives of behavioural science.