Five political lessons from social psychology

There's a must-read post by Danny Finkelstein summarising five of the 'sexiest ideas on the political scene'. They all relate to social psychology:

1. Social Norms: This is based on a simple observation - people copy each other. We take cues from others in our peer group about how to behave. This is a more powerful social force than legal restrictions. Could we, for instance, increase the amount given to charity simply by telling people how much more everyone else is giving?
2. Reciprocal Altruism: Why do we help those who are not blood relations? Surely this wouldn't be a good evolutionary strategy? Well, it turns out that it is. We help others because we believe they will reciprocate. In order for this to work, game theory demonstrates, we have to believe we will be interacting with the same people repeatedly.
3. Situationism: Is there such a thing as society? It is not just reciprocal altruism that shows that there is. It is also situationism. People behave differently when in different situations. They conform to expectations and group norms. Individuals have different dispositions but this is only part of the reason they behave as they do.
4. Prospect Theory: Thirty five years ago, innocent A level economics students would ask their teachers "but what if the consumer isn't rational?". It would patiently be explained to them that rationality was a modelling assumption, that could very easily be relaxed. It turns out that relaxing the assumption has produced the most interesting work in economics over the last three decades.
5. Cognitive Dissonance: In 1957 the psychologist Leon Festinger first put forward this idea explaining how people cling on the commitments they have made, twisting the truth round in their head to make it consistent with their existing view. Its importance for social policy is that individuals try incredibly hard to fulfill commitments they have made, verbally or in writing.

Also worth reading is this overview in the Sunday Times of the thinking behind Cameron's rhetoric on positive social norms, framed as being about using the carrot rather than the stick. I'm a big fan of this thinking and Cameron's use of the 'bully-pulpit' to promote socially responsible lifestyles (I must have been one of the only defenders of the infamous chocolate oranges comments!). It's fascinating territory.