Fortean Times, July 2004

Critical Mass: How one thing leads to another
Philip Ball
William Heinemann, 2004
Hb, 25, pp644, illus, notes, bibl, index, ISBN 0 434 01135 5

It's a cliché to say that some new discovery or area of study sounds like science fiction, but the fields of inquiry given the blanket term of the 'physics of society' are remarkably similar to the 'psychohistory' of Isaac Asimov's 'Foundation' novels. An increasing number of researchers in a host of disciplines are borrowing the analytical techniques of physics, particularly those concerned with magnetic materials or describing changes between physical states, to model the behaviour of anything from traffic jams to the global stock markets.

The basic metaphor is an appealing one for sociologists and physicists alike – you can't predict with much confidence exactly how a single person is going to behave, any more than a physicist can predict exactly what a single particle will do under certain conditions. But knowing something about those conditions allows you to make statistical predictions about the behaviour of large numbers of subjects, whether people or particles.

Philip Ball, a former editor for the prestigious science journal Nature, has produced a sprawling account of the application of science to social, economic and political issues. The book begins with a history of attempts to apply rationalism to social questions from Hobbes and Hume onwards, and of pioneering work by Maxwell, Boltzmann and others in understanding physical phenomena in terms of the statistics of multitudinous interactions, before detailing the synthesis of these two lines of inquiry.

There's something here for everyone – the causes of crime, how cities develop, cold war brinksmanship, how panics spread through a crowd, the shape of the internet, and that old favourite, the 'six degrees of Kevin Bacon' networking game. It's a rewarding cornucopia of topics, but while the book is elegantly written throughout its 600 pages, the sheer weight of material means that some areas are given a rather more superficial consideration than others.

The largest section is on economics which, despite the pretensions of some practitioners, remains the dismal science. Ball notes that economic models are persistently incompetent in the sense that they repeatedly fail to make predictions comparable to those of the most humdrum science. It is also perhaps the last area of the secular world where ideology – more often derived from Adam Smith than Karl Marx – is so widely taken for scientific law, and where billions of dollars are staked on such quasi-mystical concepts as Elliot waves.

It's all fascinating stuff, though the ultimate utility of social physics remains to be seen. Most of the work described here is based on fitting observed or past behaviour to some physics-based model, rather than anything with real predictive power. There's also a political angle to such a reductionist philosophy, which Ball does briefly address. The observation that most societies have a similar pattern of wealth distribution, for instance, can easily be used as an excuse to avoid addressing urgent social issues. With an inescapable social and cultural bias in any 'law of society', such an argument would fall into the old trap of mistaking the map for the territory.

From a fortean perspective, such physics-based models are also flawed in their apparent inability to describe the anomalous and extreme behaviours that fill the pages of FT. Given the historical content of the book, it's disappointing to find no reference to Charles Mackay's classic 'Extraordinary Popular Delusions and the Madness of Crowds', an equally weighty tome on mass behaviour. There's no reference to Asimov's 'Foundation' either.