I n Turing’s Cathedral, George Dyson gives us a personal history of computing’s early years. A science historian and son of phys- icist Freeman Dyson, he recounts a boyhood spent in 1950s Princeton, New Jersey, pok- ing around the forgotten detritus of an early digital computer in the Institute for Advanced Study (IAS). He gives us, too, the engaging tale of how Hungarian mathematician John von Neumann built a computer at the institute. But this is just one of the origin stories of the digital age. Perhaps, at the time, Princeton seemed to be the centre of the Universe. The IAS was founded in 1930 by Louis Bamberger, a department-store magnate who cashed out just before the Great Depression. Dyson relates how its first director, Abraham Flexner, decided to focus on mathematics and theoretical physics at a historic moment, when pre-eminent Europeans such as Kurt Gödel, Albert Einstein and von Neumann were moving to the United States. Princeton became a clearing house for Jewish scientists, with IAS mathematicians and physicists housed in Princeton University’s Fine Hall for the first years of the IAS’s existence. To this intellectual crucible came Alan Turing, an English graduate student who had solved the ‘decision problem’ set out in 1928 by David Hilbert, a mathematician at the University of Göttingen in Germany. In 1931, Gödel’s incompleteness theorems had ended Hilbert’s decades-long quest for a logically complete and consistent arithmetic, and by 1936 Turing and Princeton University math- ematician Alonzo Church had independently proved that there were numbers that could be specified but never calculated. Church recognized Turing’s paper to be, remarkably, more general than his own, and invited the young man to study at Princeton for two years. In tackling the problem, Turing had created a hypothetical machine that could compute anything that could be computed. This device, later named the Turing machine, became a central conceptual model for computing. Turing’s 1936 paper On Computable Numbers was consulted so often that Princeton’s copy fell apart. Although Dyson’s title anticipates the Turing centennial this June, the book revolves around von Neumann. Dyson says little about their direct interactions; von Neumann admired Turing’s work sufficiently to offer him a fellowship at Princeton in 1938, but Turing returned to England. Also left offstage is Turing’s wartime work on code-breaking and early computing, which brought him sub- stantial fame beyond mathematics. Instead, Turing’s Cathedral relates von Neumann’s effort to build an early electronic digital computer. Dyson’s account, based on the IAS archives and access to oral histories from von Neumann’s family and many close Turing’s Cathedral: The Origins of the Digital Universe GEORGE DYSON Pantheon/Allen Lane: 2012. 432 pp. $29.95/£25 John von Neumann led US efforts to develop an early electronic computer, in parallel with similar projects in the United Kingdom. TURING AT 100 A legacy that spans science: nature.com/turing PHOTOQUEST/GETTY COMPUTER SCIENCE Digital dawn Thomas Misa ponders a history of computing that focuses firmly on John von Neumann and the ‘Princeton crowd’. 32 | NATURE | VOL 483 | 1 MARCH 2012 BOOKS & ARTS COMMENT © 2012 Macmillan Publishers Limited. All rights reserved