Leo the Mathematician

Leo the Mathematician, also known as Leo the Grammarian or Leo the Philosopher, was a Byzantine philosopher and logician who lived from about 790 until after January 9, 869, associated with the Macedonian Renaissance and the end of the second period of Byzantine Iconoclasm. He served as archbishop of Thessalonica before heading the Magnaura School of philosophy in Constantinople, where he taught Aristotelian logic, and has been described as the cleverest man in Byzantium in the ninth century for intellectual accomplishments spanning philosophy, mathematics, medicine and science, though most of his original writings are lost; his only preserved writings are notes contained in manuscripts of Plato's dialogues.