Carlo Rovelli (translated by Marion Lignana聽Rosenberg)
(Allen Lane)
ASTRONOMY was conducted at Chinese government institutions for more than 20 centuries before Jesuit missionaries turned up and, somewhat bemused, pointed out that Earth is round. Why, after so much close observation and meticulous record-keeping, did 17th-century Chinese astronomers still think Earth was flat?
Theoretical physicist Carlo Rovelli addresses this in Anaximander and the Nature of Science, his first book, released in French in 2009 and now published in the UK for the first time in this lively English translation. He can be certain of one thing: 鈥渢he observation of celestial phenomena over many centuries, with the full support of political authorities, is not sufficient to lead to clear advances in understanding the structure of the world鈥�.
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So, how had Europeans managed to come to this insight? Rovelli ties his answers to the life and work of Anaximander, born in 610 BC in the cosmopolitan ancient Greek city of Miletus, .
We know about that work mostly through Aristotle because Anaximander鈥檚 only known treatise is lost, aside from a tantalising fragment revealing his notion that there are natural laws that organise phenomena through time. He also worked out the causes of wind and rain, and deduced that all animal life came from the sea, arising from fish or fish-like creatures.
Rovelli isn鈥檛 interested in such examples of apparent prescience. He is enchanted, though, by the quality of Anaximander鈥檚 thought. Take the philosopher鈥檚 most famous observation 鈥� that Earth is a finite body of rock floating freely in space. Anaximander suggests there is a void beneath Earth through which heavenly bodies like the sun must travel when they roll out of sight.
This isn鈥檛 saying much more than: when someone walks behind a house, they will reappear on the other side. Yet what makes this observation so radical is that, when applied to heavenly bodies, it contradicts everyday experience, where objects fall in one direction. The fact that the sun rises again suggests that space doesn鈥檛 have a privileged direction in which objects fall 鈥� an idea that runs against 鈥渃ommon sense鈥�.
So, Anaximander arrives at a concept of gravity: he calls it 鈥渄omination鈥�. Earth hangs in space without falling because it doesn鈥檛 have any particular direction in which to fall, and that is because there isn鈥檛 anything around big enough to dominate it. You and I, being much smaller than Earth, fall towards it. 鈥淯p鈥� and 鈥渄own鈥� are no longer absolutes, they are relative.
The second half of Rovelli鈥檚 book is less exciting, but more trenchant, perhaps to compensate for covering more familiar territory. It explains how science, evolving out of Anaximander鈥檚 attitude towards his teacher Thales, developed into a quite unnatural way of thinking.
Thales, in Anaximander鈥檚 view, was a wise man who was wrong about everything being made of water. The idea of being wise and wrong simultaneously, says Rovelli, can only come from a sophisticated theory of knowledge, 鈥渁ccording to which truth is accessible but only gradually, by means of successive refinements鈥�.
All Rovelli鈥檚 wit, intellectual agility and most of his charm are in evidence in this thrilling early work, as he explains how Nicolaus Copernicus perfects Claudius Ptolemy鈥檚 work by applying his mathematics to a better question, and how Albert Einstein perfects the work of Isaac Newton by pushing Newton鈥檚 mathematics past a priori assumptions. Nothing is thrown away in such scientific 鈥渞evolutions鈥�. Everything is repurposed.
Simon Ings is a writer based in London
