Gemistus Pletho
He was born Georgios in Constantinople in c. 1400 and he was an ethnic Greek. His abecedary was Mark of Ephesus (d. 1444). Following his tutelage under the famous John Chortasmenos ("didaskalos" of the Patriarchal School), Manuel-Mark might have then recommended him to study under his own previous master, Georgios Gemistus Pletho (d. 1452/1454), c. 1428. However, his studies under Pletho are a matter of speculation and, at any rate, would have been more likely attendance at Pletho's lectures at Mistra. Scholarius had been a teacher of philosophy before entering the service of the emperor John VIII Palaeologus as a theological advisor. In fact, in 1437 – in anticipation of the Council of Ferrara-Florence – the emperor formally studied Nilus Cabasilas's works along with Mark of Ephesus and Gennadius Scholarius. Curiously, the trio also formally studied the works of John Duns Scotus (d. 1308) because of his rejection of the Filioque in Thomistic metaphysics, as well as Scotus' doctrine of a "formal distinction" between the persons and essence of God, as well as God's attributes (or "energies"). It was for this reason that Scholarius wrote an academic refutation of the first eighteen of Mark of Ephesus' "Syllogistic Chapters against the Latins." From this, we can surmise that Scholarius was likely writing an academic exercise to inform his former master that Thomas Aquinas' opinions did not constitute a universally Latin approach to questions on the Trinity.