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THE NEOPLATONIC SCHOOL OF HELLENOPOLIS (CARRHAE, HARRAN), by Jean Efpraxiadis (February 2017)
It is now largely agreed that there was a high quality school of Greek philosophy in Harran (Grk. Ελληνόπολις, Κάρραι) as a result of that city being the final destination of at least one among the seven neoplatonic philosophers exiled by Justinian in 529, namely Simplicius. These refugee philosophers had first spent a few years with Sassanid king Khosrow whom they affectionately called "Plato's philosopher king". Pursuant to terms of a peace treaty negotiated between Justinian and Khosrow, the Greek philosophers were allowed to return to the Roman Empire.
The view that they might have returned back to Athens now appears implausible. It is now believed that they settled in Harran, a city on the Byzantine side of the border with the Sassanid Empire, where they could easily escape and find refuge again, if it became necessary. Harran had remained a Pagan city: Hellenism was practiced side-by-side with the indigenous Mesopotamian religion and there were also some Manichaeists/Zoroastrians. It was an ideal place to found a school of Platonism. In a way, it was a school of all Greek philosophy and science, since they were the last remaining curators of all ancient knowledge, the most erudite people then alive.
The school must have outlasted the lives of its founders as well as the Islamic conquest one century later. Harran had become a rather unique place indeed. Its population was not religiously persecuted. According to Abu Yusuf Absha al-Qadi, Caliph al-Ma'mun of Baghdad in 830 CE questioned some Harranians about what protected religion they belonged to. As they were neither Muslim, Christian, Jewish or Magian, the caliph told them they were non-believers. He said they would have to become Muslims, or adherents of one of the other religions recognized by the Qur'an by the time he returned from his campaign against the Byzantines or he would kill them. The Harranians consulted with a lawyer, who suggested that they find their answer in the Qur'an II.59, which said that Sabians were tolerated. It was unknown what the sacred text intended by "Sabian" and so they took the name.
Two of the most illustrious mathematicians and astronomers of the Arab world were Sabians from Harran. Thabit ibn Qurra and al-Battani were born in Harran in 826 CE and c.858 CE respectively. Thabit had such an extensive knowledge of Neoplatonism and Greek science that can only be explained if he had grown up in it. He was so proficient in Greek as to be able to revise the translations of Hunayn ibn Ishaq, known as the "Sheik of all translators". Arab historians such as Al-Mas'udi knew more about Simplicius' biography and career than the Byzantines. Al-Nadim and al-Qifti list Simplicius as a famous mathematician, a fact that the Byzantines seemed to not know or to not remember about him. Al-Qifti actually mentions Simplicius as the author of a commentary on Euclid's Elements. This lost work of Simplicius was not known to the Byzantines. Extensive fragments of it survive in an Arabic translation used by Persian mathematician Al-Nayrizi to write his own commentary on the Elements at around 900 CE. This is a case where the Arabs had access to Greek mathematical works that the Byzantines didn't even know existed.
The Byzantines did not know of Simplicius' commentary on the Elements of Euclid but a very few of them had studied the Elements themselves, in particular Leo the Mathematician, also known as Leo the Philosopher or Leo the Hellene and his anonymous and enigmatic teacher in the island of Andros.
In a battle between the Byzantines and the Arabs a student of Leo was taken prisoner. Arab scholars were impressed with his knowledge of mathematics and astronomy but he explained that his teacher, Leo the Mathematician, was a lot brighter than himself. The Caliph was so impressed that he sent a letter to Leo promising him a comfortable life should he move to Baghdad and join his team of learned scholars. Leo refused the offer but he did send them answers to some technical questions in mathematics and astronomy that they had trouble with.
While in the 9th century the centre of Arabic scholarship was moving from Harran to Baghdad and a revolution in philosophy, mathematics, medicine, astronomy etc was in progress with Greek, Persian and even Chinese texts being translated, collected and studied, being a Hellenizing secularist in 9th century Byzantium was a dangerous occupation (even under the cover of being a clergyman). While Leo the Mathematician was allowed to call himself "Leo the Hellene" because of his celebrity status, the powers that be were suspicious of his devotion to ancient learning.
One of his students named Constantine accused him of being a pagan outright in a preserved elegiac poem and despite Leo's necessary apology in equally poetic form to the effect that he was not a worshipper of Zeus, Constantine had probably seen right. A few decades later, a Platonist disciple of Leo the Mathematician named Leo Choirosphaktes got in similar trouble.
Late in his career, he was sent as ambassador to Baghdad in 905 CE, a position which would have given him the opportunity to enter into contact with the Arabic renaissance that was happening there, an opportunity which his teacher had turned down. Upon his return in Constantinople he must have complained that the Arabs were progressing by leaps and bounds due to their study of Greek philosophy and science while the Byzantines were letting their manuscripts collect dust. Arethas of Caesarea, perhaps inspired by the advanced work of the Arabs, finally orders a copy of the Elements be made so as to preserve and understand the subject matter. He also orders copies of plenty of other ancient works including the works of Plato. Interestingly, he condemns Leo Choirosphaktes accusing him of Hellenism, not an unreasonable accusation seeing who his teacher had been and what kind of friends he may have made in Baghdad.
Joining Arethas in accusing Choirosphaktes of being a Hellene was Constantine the Rhodian who came up with fanciful epithets for Choirosphaktes:
"ψευδομυθοσαθροπλασματοπλόκος",
"ελληνοθρησκοχριστοβλασφημοτρόπος" and
"ολεθροβιβλοφαλσογραμματοφθόρος".
Coming from people who were devoted to higher learning and study of ancient knowledge themselves, in my opinion such accusations show one of three things: Either the accusers felt uncomfortable in their own Pagan closets, or they were afraid of being accused themselves of too much devotion to ancient learning (feeling that they could get in trouble, unless they were publicly seen by their peers as hating the "delirium of the Hellenes") or they were just jealous of Leo Choirosphaktes and felt inadequate in comparison to his erudition and virtue as a statesman. Whatever the reason may have been for accusing (or outing) Choirosphaktes, he was exiled for five years before he was pardoned by the next emperor.br>
The difference between attitudes of Arabs and attitudes of the Byzantine establishment towards advanced learning and Platonist scholars in the 9th century was stark. The Byzantines had a few brilliant people hiding in the closet communicating among themselves using dissimulation and read-between-the-lines hints while the Arabs were embracing Greek knowledge as if it were part of their own heritage, which, in a partial but non insignificant sense it was.