1431-1449: The Final Ecumenical Council - Two Churches, One Tradition
Western theology tends to be identified with post fifteenth-century Thomism. This may marginalise trends such as Scotism, Ockhamism, humanism etc. but as a generalisation it holds. That’s not to devalue the West’s pluralist traditions, which, if not eradicated were certainly disciplined by the theological drill sergeants of Peter Abelard, Peter Lombard and Alexander of Hales. But it is fairly uncontroversial to assert that the unitary principle of western theology is, in the long run, provided by scholasticism.
Meanwhile, Byzantine theology has a reputation less of a jolly, sashaying cavalier cutting a dash here or there than an officious, pogonophilic policeman stewarding folk on the roads that lead to the waters of life (Rev 22:1). Orthodoxy becomes the pure stream to which others can add only if they are willing to risk adulterating its contents.
These caricatures (which pit hermetically sealed notions of [austistic] scholasticism against [reactionary] patristics), however, risk anachronism. Many of the biggest stars in the Orthodox firmament did not work against a “Latin tradition” but participated within a shared stream of consciousness (regarding both sources and attitudes) with their occidental brethren. In truth, the medieval period saw Byzantines fascinated with scholasticism and, in turn, Latins intrigued by the Cappadocian fathers.
Instead of attempting to locate a slow and inevitable bifurcation of the Christian world, or divine how immaculate each church’s fons et origo, I hope to emphasise the common ecclesiastical tradition that flourished throughout the late medieval/early modern period – with the strong insinuation that there is, therefore, nothing predetermined about the contemporary status quo.
Perhaps the best place to start is Markos Eugenikos (Mark of Ephesus). Portrayed as the archetypal purist on the Byzantine side; a hero of resistance to papal tyranny, beneath the PR job the theologian’s jottings speak for themselves. Even in his most hostile works (such as the Syllogistic Chapters Against the Latins), in order to bring orthodox sandwiches to the ecumenical picnic, he had to set them them on a blanket of Aristotelian metaphysical principles, in this case to justify the production of the Son and Holy Spirit from a single principle.
Moreover, in the same work he found himself having to appeal to Augustine’s De Trinitate (probably M. Planoudes’ translation), Soliloquies (actually Ps. Augustine translated by D. Kydones) and select Epistles (translated by P. Kydones). In other words, the works of a theologian the modern Orthodox have framed as the font of everything exclusively Latin (and therefore suspect) within theology. Indeed, Eugenikos’ works also display a form of Byzantine scholasticism in his affinity for dialectics in relation to accomplishing a patristic synthesis, a pursuit at odds with the anti-dialectical prejudices that would otherwise force the Orthodox vanguard to describe the Ephesine as a “latinophron.”
It’s not just Eugenikos who’s been caught with St Augustine on his bookshelf. A figure no less divisive than Palamas liberally used Augustine’s De Trinitate within The One Hundred and Fifty Chapters. Furthermore, the Byzantine contingent at Ferrara-Florence had explicit recourse to the works of Bernard of Clairvaux for their Palamite position on the vision of the Blessed. In truth, the council reads less like a binary collision than might be expected. For instance, while it’s not clear whether some on the Byzantine side were ever fans of Palamism (Bessarion for example), there were also no Franciscan interventions against Eugenikos’ espousal of its theology because of their agreement with the Ephesine, ad instar Scoti.
Scholarios was certainly not shy in employing Franciscanism against Barlaamites and Acindynists. He praised Scotus and his disciples as being “more orthodox” and on the “correct side of the debate” between Thomists and Palamites. And drew on a long tradition in so doing. Few would call into question the orthodoxy of scholars such as Makarios Makres (sometimes called “Asprophrys,” the one “with white-eyebrows”). Yet his masterpiece (which he died writing, d.1431) was a giant synthesis of Aquinas’ Summa contra Gentiles and the Byzantine patristic tradition – a project that was probably as taboo then as it was now, or was it?
If Orthodoxy has its fanatical champions, so does Catholicism. At Florence, John Torquemada (uncle to the famous inquisitor) played Byzantium’s nemesis with aplomb. Nullifying “dangerous” concessions which lay outside the scope of his rather dim text-book Thomism (a position that found favour with the Dominican order) his Apparatus snuffed traces of theological pluralism and replaced it with the dull declarations of a semi-inquisitive faith; a meagre and underwhelming rendering of Christendom’s rich tapestry.
 Byzantine reactions to scholasticism were ambivalent. Some (mostly intellectuals) were excited about a project that sought to apply reason to theology as it exhilaratingly allowed total systematisation – Summa Theologica style. The majority, however, saw reason as registering low on the epistemological spectrum, reducing scholasticism to at best a Babel-esque project and at worst a displacement of revelation with a philosophy that second-guessed the mysteries of the faith, which are better wrestled with in darkness as Jacob did with God in Genesis 32.
 For an interesting discussion of Modern Greek “patristic” theologians, see N. Russell, “Modern Greek Theologians and the Greek Fathers,” in Philosophy and Theology 18 (2007), pp. 77-92.
 Revered Byzantine authors employed “Latin theology” and vice versa. Readers who cannot accept the blurred lines of the Orthodox and Catholic Churches are doubtless interested in them less as living Churches and much more as clean, pure and ultimately dead abstracts or idols.
 Mark Eugenicus, Capita Syllogistica, para. 27, 11. 23-36 – para. 31, 11. 2-7.
 This justification relies on the isolation of “generation” and “procession” with the two terms signifying different modes of emanation from an immaterial divine object. These modes can be traced back to properties (not relations that presuppose such properties) that are not formally the same with respect to each other. As such, they are sufficiently irreducible to one another as to to justify the emanation of the Holy Spirit from the Father without any direct cooperation from the Son.
 See M. Plested, Orthodox Readings of Aquinas (Oxford, 2012), ppp. 124-127 for further discussion on Mark’s scholasticism.
 The Byzantine equivalent of the common racial slang “coconut” (brown on the outside, white on the inside), Latinophron meant the peson was “Byzantine externally and Latin internally.” For pro-Latin sentiments on the Byzantine side see J. Monfasani, “The Pro-Latin Apologetics of the Greek Emigres to Quattrocentro Italy,” Byzantine Theology and its Philosophical Background, ed. A Rigo (Studies in Byzantine History and Civilization 4) 2011, pp. 167-168.
 John Lei, Tractatus Ioannis Lei O.P. “De vision beata…” p.72.
 While the Latins felt the need to swot up on Augustine and Duns Scotus, Pope Eugenius relied on both the Franciscans and humanists (movements that crossed several Thomist lines) to broach Byzantine positions. Indeed, the Franciscans proved so amenable to the Palamite line that Palamism had to be dropped as an official issue.
 The compromise between Palamites and Latins at the Council is partim the cause for John Torquemada’s Apparatus to the Council in the first place. He only managed to publish this apologetic treatise (including the condemnation of Palamism) after Byzantine participation in the Council had officially ended, and it was less a theological play than a political one that attempted to neutralise the Conciliarist criticism (hailing from Basel) that Florence had sold out to the Byzantines.
 See Oeuvres Completes de Georges Scholarios, Paris, 1928-44, Commentary on Aquinas’ De ente et essentia, 6, p.282, 11. 6-7; Against the Partisans of Acindynus: a propos a passage of Theodore Graptos 3, p. 212, 11. 25-26; On the Distinction between the Essence and its Operations 3, p. 230, 11. 9-10.
 A particularly stupid enterprise given his magister, divus Thomas, proved to be a material heretic (inter muros) on theological questions such as the Immaculate Conception and sacramental confession of mortal sins to laymen, making it a fortiori dangerous to approach theological questions from one perspective.