Known Unknowns 193 caused you to trip? You could go on Ta forever, generating rules to cover every Mint —> eventuality. Clearly, in the fuzzy world of } human endeavor, truth and rules often = part company. Yet, we all assume math- \ 7* ' ematics is free of such uncertainty. Let > RE me tell you this is not so. The brilliant a . mathematician Kurt Géddel proved se : oe this when he was just 22, and his proof a oe says something fundamental about the 4 e /, nature of knowledge. oe cy ri The story of his discovery involves “ some of the greatest mathematical Kurt Gide! thinkers in history. My introduction to it came about from a chance accident. I became ill in my first year at University (mononucleosis, otherwise know as glandular fever, if youre curious) and was eventu- ally sent home to recover. Lying in bed for two months is boring. So to pass the time my mother suggested I read Bertrand Russell's, The History of Western Philosophy. I think she figured I had plenty of time, so picked a thick book. This nearly 800-page tome charts the entire history of philosophy from the time of the ancient Greeks. I presumed Russell was a philosophy professor, but he was originally a mathematician. He was a mathematician. And because he lived and worked productively for almost all of his 97 years, spanning much of the 19" and 20" centuries, he crops up repeatedly as a central figure in many areas of intellectual life. Russell the politician, Russell the philosopher, Russell the mathematician and Russell the peace campaigner are all the same man — not, as I had incorrectly first guessed, a prolific family. In his early career, Bertrand Russell was a Fellow of Trinity College, Cambridge, working on a broad range of mathematical problems. Meanwhile, in Germany, his contem- porary David Hilbert, also a polymath, held the chair of mathematics at Gottingen University. Both men shared a common objective: to tidy up the loose ends in mathematics and set down the rules once and for all.