The Man of Numbers

Best known for his integer sequence (in which each term is the sum of the two previous terms -- 1, 1, 2, 3, 5, 8, 13, and so on), Fibonacci's most important contribution to mathematics was, in fact, the replacement of Roman numerals with the Hindu-Arabic notation we use today. Keith Devlin here unpacks the history behind this breakthrough, which revolutionized European trade as the Renaissance dawned, in a fascinating book reminescent of Dava Sobel's Longitude.

July 25: On this day in 1834 Samuel Taylor Coleridge died of heart disease at the age of sixty-one.

Crime fiction legends Dennis Lehane and Michael Connelly discuss the new book that unites their beloved sleuths Patrick Kenzie and Harry Bosch.