The wisdom of crowds: why the many are smarter than the few. We-think: the power of mass creativity. Infotopia: how many minds produce knowledge. Wikinomics: how mass collaboration changes everything. These are the titles of just a few of the books published in recent years on one of the hot topics of the moment: knowledge aggregation, or how lots of different people knowing many small things can result in a very big deal for everyone. The obvious impetus behind this publishing trend is the internet, which has generated astonishing new ways of finding out all the different things that people know and bringing that knowledge together. If you look for these books in bookshops (itself rather a quaint idea given that you’re supposed to be buying them online), you’ll discover them in the business or management sections, where their lessons about openness, flexibility, innovation and the importance of listening to what your customers are telling you have their most immediate applications. But the authors are usually more ambitious than this and want to apply their notions beyond the confines of management studies – and in social policy. If businesses can use the wisdom of crowds to predict what people really want, to innovate new ways of providing it, and to test whether it actually works, why can’t politicians?