One day on the streets of Alexandria, Egypt, in the year 415 or 416, a mob of Christian zealots led by Peter the Lector accosted a woman’s carriage and dragged her from it and into a church, where they stripped her and beat her to death with roofing tiles. They then tore her body apart and burned it. Who was this woman and what was her crime? Hypatia was one of the last great thinkers of ancient Alexandria and one of the first women to study and teach mathematics, astronomy and philosophy.