fl. c. 320

Syrian philosopher whose work emphasized the mystical aspects of Pythagorean number theory. According to Iamblichus, Pythagoras (c. 580-c. 500 B.C.) himself had discovered "amicable" numbers, pairs in which each is the sum of the other's proper divisors. By expanding on the nonscientific aspects of Pythagorean mathematics—aspects that indeed did go back, in many respects, to ideas of Pythagoras himself—Iamblichus helped perpetuate interest in numerology, magic, and astrology.