Hidden Harmonies

Is "a squared plus b squared equals c squared" more famous than "e equals mc squared?" The theorem formulated by Pythagoras has certainly been around longer than Einstein's, thereby accruing a commensurately greater amount of lore and usage. With mathematical insight and welcome wit, Ellen and Robert Kaplan trace the influence of the Pythagorean theorem through the millennia—enlisting the help of Leonardo Da Vinci, President James Garlfield, and the Freemasons along the way.

July 24: On this day in 1725 John Newton, the slave trader-preacher who wrote the hymn "Amazing Grace," was born.

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