IT鈥橲 just a simple fact about right-angled triangles, but Pythagoras鈥檚 theorem is also one of the world鈥檚 oldest and most famous ideas. This excellent biography of the theorem is like a history of thought written in lines and circles, moving from ancient clay tablets to Einstein鈥檚 blackboards. It presents a selection of the hundreds of proofs, including one from James A. Garfield, the 20th US president. There is something intoxicating about seeing one truth revealed in so many ways. It all makes for hours of glorious mathematical distraction.
The Pythagorean Theorem: A 4000-year history
Princeton University Press