The Physicist and the Philosopher by Jimena Canales (Princeton, £24.95)
Everyone has heard of Einstein, fewer know the name Henri Bergson. Yet in 1922, when they debated in Paris, Einstein was the less well known. Bergson, the grand man of French philosophy, dominated international intellectual life. On a lecture tour of the US, he attracted a crowd so large it caused Manhattan’s first ever traffic jam.
Jimena Canales, a professor of the history of science at the University of Illinois, sets out with skill Bergson’s objections to Einstein, which centred on his treatment of time. Relativity banished “real” philosophical time. Einstein’s theory said that simultaneity—two events occurring at once—was a mirage and that time perception depended on an observer’s position. More outrageous still, a clock travelling at close to the speed of light would mark time more slowly than an identical stationary clock.
Bergson wasn’t having any of it. Relativity violated fundamental philosophical ideas, chief among these, “duration.” Einsteinian time is chopped into the ticks of the clock, passing as if in frames, like cinema film through a projector. This violated the most essential intuitive sense that time is a progression, said Bergson. The measurement of time and time itself are two distinct things.
The two met only once, but the ensuing argument lasted for decades. It is tempting to see this as science versus philosophy. Yet Einstein was supported by philosophers and Bergson by physicists, especially quantum physicists, who saw in Bergson’s work the seeds of their own, non-deterministic view of the universe.
To look for a winner is to miss the point. The lesson of this repetitive but balanced story of intellectual intransigence is that nobody should be immune to challenge, no matter how famous his or her equations, or how big a snarl-up he can cause on Broadway.