Giordano Bruno, the most famous of the Italian philosophers of the Renaissance, was born at Nola, near Naples. At an early age he entered the Dominican order and became an inmate of the Dominican convent in Naples. In 1576 he was accused of heresy and fled, abandoning the Dominican habit. Thereafter he wandered through Europe. After visiting Geneva, and lecturing on the Tractatus de Sphaera Mundi of Sacrobosco at Toulouse, Bruno reached Paris in 1581. Here he gave public lectures that attracted the attention of King Henri III, and published two books on the art of memory that reveal him as greatly influenced by that textbook of Renaissance magic, the De Occulta Philosophia of Henry Cornelius Agrippa, from which he quotes lists of magic images of the stars, incantations, and other occult procedures. Bruno as a Renaissance magus, in line of descent from the learned philosophical...