The House of Wisdom sounds a bit like make-believe: no trace remains of this ancient library, destroyed in the 13th Century, so we cannot be sure exactly where it was located or what it looked like. But this prestigious academy was, in fact, a major intellectual powerhouse in Baghdad during the Islamic Golden Age and the birthplace of mathematical concepts as transformative as the common zero and our modern-day “Arabic” numerals. Founded as a private collection for caliph Harun Al-Rashid in the late 8th Century then converted to a public academy...