Syrian philosopher noted for his mathematical commentaries. A student and close associate of Plotinus (205-270), the founder of Neoplatonism, Porphyry tried to bring together the ideas of Plato (427-347 b.c.) and Aristotle (384-322 b.c.). His commentary on the latter's Categories influenced the development of logic, while his writing on the Elements of Euclid (c. 325-c. 250 b.c.) apparently provided Pappus (fl. c. 320) with a principal source. Porphyry also wrote a biography of Pythagoras (c. 580-c. 500 b.c.) Among his students was Iamblichus (fl. c. 320), who took a very different, and less scientific, approach to mathematics than his teacher.