What does physics have to say about the workings of society? Quite a lot, most readers of Econophysics Forum will probably agree, but I suspect even here most will be surprised at how much Philip Ball has squeezed into the pages of a paperback book. From multi-agent modelling, crowd and traffic dynamics, financial markets and networks to the development and growth of firms, war, crime, politics and the spread of culture, <em>Critical Mass</em> is a remarkable survey of an ever-growing field, that mixes fine storytelling and a deft feel for interesting social phenomena with elegant descriptions of the various theories proposed to explain them.
