In 2008, the behavioral economist Richard Thaler and the legal scholar Cass Sunstein published a book in which they advocated a novel approach to public policy based on the notion of a ‘nudge’. Roughly speaking, a nudge is an intervention in the decisional context that steers people’s...

We argue that the diverse components of a choice architecture can be classified into two main dimensions – Message and Environment – and that the distinction between them is useful to better understand how nudges work. In the first part of the paper, we define what we mean by nudge, explain...