In or around 1637, Pierre de Fermat wrote in the margin of a maths book notes describing what became known as Fermatean Triples. He claimed to have found an equation that was hard to solve. "I have a truly marvellous demonstration of this proposition which this margin is too narrow to contain". That one sentence was to tease mathematicians for centuries. The proposition, known as Fermat's Last Theorem, is simple to describe such that even a child can understand it: that there was no solution to the equation "a**n + b**n = c**n" (where '**' is 'to the power of', a, b, and c are whole numbers greater than 1, and 'n' is greater than 2).
Written like a detective story where the answer is known, this book is easy to follow, and leads readers through a maze of ideas, concepts and subtleties that would be a disaster in the hands of a lesser writer. This is absorbing narrative, leading up to the lecture where Andrew Wiles presented his proof of the non-solution of the equation. However, the proof presented on 23rd June 1993 was the beginning of a nightmare for Wiles, as a serious logic error was subsequently discovered that took an all-consuming 15 months to rescue.
The story of how a very gifted mathematician devoted himself for seven secretive years to a question that others had given up on is only half the tale that Singh tells. It is a journey through some of the history of mathematics, with the solution to the amateur mathematician Fermat's problem being an accidental occurrence. Along the way there are very good insights into the differences between mathematical proofs and scientific proofs; the former must be indisputable, whereas scientific proofs are only ever probabilistically true, and do change as knowledge increases.
There is no need for a great interest in or knowledge of mathematics to enjoy the story, which itself draws the reader onwards. I k now nothing of the similarities between modular equations and elliptical equations, tied up within what became known as the Taniyama – Shimura conjecture, yet can appreciate the means by which Wiles was able to prove Fermat's theorem by establishing the mathematical truth of the latter.
Simon Singh started by investigating the story of Andrew Wiles and Fermat for a British television program. This book that he subsequently produced set new levels for the history of science as a popular writing genre. At the end, Singh goes further, and raises questions as to whether the discovery was worth it. If Wiles had not been able to rescue his proof, it is suggested that the effort would not have been in vain, as there were significant advances in mathematic knowledge obtained in the trying. Singh also discusses other difficult areas, and muses on whether some of these will be unprovable, or insoluble. Fermat's Last Theorem, having frustrated the best mathematical brains for over 350 years, is now established, and is not one of the 'unknowable truths of mathematics'!
In concluding, it is fitting to use the words with which Andrew Wiles concluded his 1993 lecture: "I think I'll stop here".
Peter Morgan Bath, UK (email@example.com)