The 1261 reconquest of Constantinople from the Latins provided the Byzantine Empire not only the opportunity to reconfigure its political and military position internationally-wise, but it also revived its cultural life, thus emerging what some experts in the Byzantine history and culture have dubbed the last Byzantine Renaissance, or the Palaiologan Renaissance, never matched in the history of this Empire. Whether the term "Renaissance" is indeed correct remains to be debated; however, this cultural trend, manifest in times of political decline, represented the last great substantiation of the Byzantine spirit before the storm, namely the conquest of Constantinople by Mehmed II in 1453. Undoubtedly, this period of cultural flourishing generated the zest of what Nicolae Iorga would call the post-Byzantine times: "Byzantium after Byzantium".
Four polemic directions were dominant during this period, and are addressed by this research project. Chronologically, they are: 1) the polemics against the Latins and the debates on the union of Churches; 2) the debate over the philosophies of Plato and Aristotle and their importance for Christian theology; 3) the Palamite controversy, concerning St. Gregory Palamas' hesychast theological synthesis, strongly rooted in the theology of Dionysius the Areopagite and Maximus the Confessor; and 4) the polemic against the Islam, which started before the settlement of the Turks on the European territory of the Byzantine Empire (1354), and was supported by the Greek translation of a Latin anti-Islamic text.
I. The polemic against the Latins is a very important issue, rooted in the Great Schism of the Church, which now acquired a theological and philosophical dimension. Moreover, Latin theology now appears to the Byzantines as a well-structured science, philosophically supported by the writings of Thomas Aquinas, translated into Greek by Demetrius Kydones, an official at the court of Emperor John VI Cantacuzenus. Given that the manual for learning Latin offered to Kydones by an anonymous Latin monk of Pera was Aquinas' Summa Contra Gentiles , which also criticized the Greeks, then the polemical spirit is manifest even in the intention. Intellectuals such as Prohor Kydones, brother of Demetrius, Manuel Kalekas or Georgios Genadios Scholarios continued the translation into Greek of the Latin theological and philosophical writings.
On the other hand, the polemic with Latin theology was stimulated by the two unionist councils, of Lyon (1274) and Ferrara-Florence (1438/9), both of them failed from the perspective of the Church, but playing a paramount role in bringing together the two worlds, Greek and Latin, separated by the schism. One outcome was the fact that Byzatines such as Manuel Kalekas (d. 1410), Theodore of Gaza, Bessarion, Isidor of Kiev, George of Trebizond etc, most of them seduced by Latin theology, and therefore mockingly dubbed latinophrones (those who think like the Latins), came to the Occident, and some of them even joined the Roman Church, and converted to the Latin faith, while others, both to earn their living and out of intellectual interest, established Greek language schools, thus invalidating the old Latin adage graecum est non legitur (it is Greek, [therefore] it is not read). The West naturally re-discovered its roots.
II. The debate over the philosophies of Plato and Aristotle took three distinct directions: a) a theological one, attempting to demonstrate that one of the two philosophers was closer to Christianity, presenting one or the other as some kind of a pagan prophet of the natural Revelation - such was the early 14th-century controversy between Nikephoros Chumnos and Theodore Metochites; b) the second one, represented by philosophers such as Georgios Gemistos Plethon (1355-1452), who attempted to demonstrate that Plato's metaphysics is the true one, while Aristotle's is false, and thus raising the question: who is in the Truth and who is not, deliberately ignoring Christianity, as this philosopher proved to be a neo-pagan; c) an "irenic" direction, according to which the two philosophers were reconciled, as they expressed the same truth in different ways, and thus were close and useful to the Christian Church. Bessarion (1403-1472), through his philosophical works, seems to be the most important irenic spirit.
For the first time since Plato's indirect condemnation as a heretic through John Italos by the 1082 Council of Constantinople, the Athenian philosopher is acknowledged as autorithative in the Byzantine cultural milieu and only those who do not know his spirit at all maintain their reserve. Most likely, most thinkers only appreciated his intuition of a revelation preached by the Church, but there are no true Platonicians over these three centuries. Moreover, Plethon dares to consider him the source of a type of revelation he thoroughly describes in his Treatise on Laws. He did not shy away from "preaching" Plato in private discussions with Italian scholars, during the Ferrara-Florence council, and he even wrote a text in the spirit of this polemic, entitled: On the difference between the philosophy of Plato and Aristotle, or De differentiis. However, after the Ferrara-Florence episode, the Byzantines wrote against this apology of Plato, intended to incriminate Aristotle. Gennadios Scholarios, Plethon's main opponent, defended Aristotelus Christianus against Plato Paganus. Plethon also established the Platonic Academy of Florence, about twenty years after the respective council, according to Marsilio Ficino, the first head of the above-mentioned school. This academy issued the first Latin edition of Plato's works, as well as one of Plotinus, whose school had inspired Plethon, consciously or unconsciously.
III. The Palamite controversy, on St. Gregory Palamas' hesychast theological synthesis, was the last theological synthesis of Byzantium, and influenced the entire Orthodox post-Byzantine theology, even more than the theological currents sanctioned by Ecumenical Councils. Under the crucial influence of two Church Fathers, namely St. Dionysios the Areopagite and St. Maximus the Confessor, the promoter of hesychasm (the doctrine of God's revelation through His uncreated energies, emanating from Him but different from His essence), St. Gregory Palamas is both a platonician and an aristotelician, not because he accomodated them with the Church, but by using both of them methodologically, in order to demonstrate the revealed truth of the Church. The hesychast controversy is relevant not only to Eastern theology, since the main opponent of the hesychasts was a Greek coming from Southern Italy, familiar with Latin theology and Aristotle's philosophy. It is a complex cotroversy with Western theology, through Barlaam of Calabria, a controversy with Platonician philosophy through Nikephoros Gregoras, the second opponent of Gregory Palamas, as well as a controversy within Byzantine scholasticism through Gregory Akyndinos. Even today, the hesychast doctrine radically separates Orthodox East from Catholic West, basically the difference consisting of the manifestation of God's essence and the ways of knowing Him.
IV. The polemic against Islam is an older issue in Byzantium. The first to criticize Islam in the Christian world was St. John Damascene (Arabic: Yahia ibn al Mansur), followed by Theodore Abu Qurra, who can be considered the first genuinely Orthodox polemicist in the Oriental world. During the Palaiologan period, the old polemic against Islam was resumed, less based on the literature of Eastern writers and more on the Occidental one, which had certainly appeared as an expression of the Western world encountering the Muslim world during the crusades. The main Occidental source is Confutatio alcorani, by Riccoldo da Monte di Croce (Lat. Ricoldus de Monte Crucis), an Italian dominican strongly influenced by the theology of Thomas Aquinas, translated into Greek by Demetrios Kydones. The monk Joasaph, the former Byzantine emperor John VI Cantacuzenus, wrote under the influence of this book. Actually, the first observer of Islam at the times was Gregory Palamas, who in a letter to the Christians of Thessaloniki, described the burial rite in the Islam as well as some of the fundamental principles of this religion, which he had discovered during his conversation with the Muslim priest who had performed burial. We cannot talk of a critical attitude with St. Gregory Palamas, unlike Joasaph, but a synthesis of the two is provided by emperor Manuel II Palaiologos in his Dialogue with a Muslim.
An overall view on the research
A detailed presentation of research would require a different approach, and an explanatory list of all books and articles would take much space. Therefore, I shall confine myself to presenting the most important syntheses concerning the Palaiologan period. I mention that a synthesis of the project's topic is yet to be published, but there are ample works on the above-mentioned period, from the historical, political, economic and religious standpoint. Very important for the historical and political approach of the times is the work of the British scholar Donald MacGillivray Nicol, The Last Centuries of Byzantium, 1261-1453,Cambridge University Press, 19721 and 19932. A highly pertinent social-economic analysis is the work of the reputed German scholars Klaus-Peter Matschke and Klaus Tinnefeld, Die Gesellschaft im späten Byzanz. Gruppen, Strukturen und Lebensformen,Köln-Weimar-Wien, 2001. On the position of the Church in the Byzantine society, and the latter's impact on the former's life, the relatively recent work of the British Donald MacGillivray Nicol, Church and Society in the Last Centuries of Byzantium,Cambridge University Press, 2008, is highly relevant. Although they are not explicitly centered on the Byzantine period, the syntheses of Hans-Georg Beck, Kirche und theologische Literatur im byzantinischen Reich, München, 19591 and 19772 and that of Herbert Hunger, Die hochsprachliche profane Literatur der Byzantiner,München, 1978, are very important. On the history of the Orthodox Church in the Byzantine Empire, we must of course mention Hans-Georg Beck, Geschichte der orthodoxen Kirche im byzantinischen Reich,Göttingen, 1980 and J.M. Hussey, The Orthodox Church in the Byzantine Empire, Oxford, 19861 and 20102. Special attention is granted to the Palaiologan period from the perspective of the theology-philosophy relationship, although this is not the exclusive topic, in the early work of the German Byzantinologist Gerhard Podskalsky, Theologie und Philosophie in Byzanz, München, 1977.