He [ Ammonius ] adopted the doctrines which were received in Egypt concerning the Universe and the Deity, considered as constituting one great whole; concerning the eternity of the world, the nature of souls, the empire of Providence and the government of the world by daimons. He also established a system of moral discipline which allowed the people in general to live according to the laws of their country and the dictates of nature; but required the wise to exalt their minds by contemplation and to mortify the body . . . and ascending after death to the presence of the Supreme Parent. In order to reconcile the popular religions, and particularly the Christian, with this new system, he made the whole history of the heathen gods an allegory, maintaining that they were only celestial ministers entitled to an inferior kind of worship; and he acknowledged that Jesus Christ was an excellent man and the friend of God, but alleged that it was not his design entirely to abolish the worship of demons, and that his only intention was to purify the ancient religion.
Edinburgh Encyclopedia (First American Edition, edited by David Brewster, published 1832)
I have urged that Ammonius was an independent thinker who, though a Platonist, had a weaker commitment to Plato than most of his contemporary Platonists and hence was uninterested in interschool polemics. His concern rather was to search for the truth in philosophy, which led him to study the works of both Plato and Aristotle and appreciate them according to their merits. Focusing on the underlying thought behind the texts, Ammonius left aside doctrines forged by later philosophers, points of detail, and also certain flaws of the philosophers themselves, and reached an understanding of Platonic and Aristotelian philosophy as a whole, concluding that their basic doctrines are essentially the same. We do not know which these doctrines were, but I have proposed that one such doctrine was that Plato and Aristotle maintain that there is only one God, that is, an intellect which accounts for both the intelligible and the sensible reality and this principle summarizes the entire intelligible realm, on the assumption that the transcendent Forms constitute the divine thoughts. I have also argued that Ammonius is likely to have considered the two philosophers in accord also on how God accounts for the existence of the world and how the intelligible and the sensible realm relate to each other. An agreement on such issues would have suggested to him that Aristotle was attached to the essence of Plato’s philosophy, which for him consisted in metaphysics.
Ammonius’ thesis may have triggered some discussion. We hear that his contemporary Platonist Eubulus wrote a work entitled On Aristotle’s objections to Plato’s Republic, but we do not know anything about it. Plotinus, however, disagreed with the unqualified acceptance of Ammonius’ thesis and, as we will see in the next chapter, he often criticizes Aristotle for departing from Plato’s doctrines. Yet the fact that he did pay considerable attention to Aristotle and his Peripatetic commentators may well attest to Ammonius’ impact upon him.
George E. Karamanolis, book entitled: Plato and Aristotle in Agreement: Platonists on Aristotle from Antiochus to Porphyry, first published in 2006.
Neoplatonism begins with Ammonius Saccas, but almost nothing is known of this philosopher. He was born in Alexandria, Egypt in about 175 A.D. His parents were poor and he received little formal education. According to the writers Suidas and Ammianus Marcellinus, Ammonius, as a young man, had earned his living as a porter (corn carrier) on the docks of Alexandria, hence his nickname of "Sack-bearer" (Saccas for sakkophoros).
Ammonius Saccas was a self-taught philosopher; even so, he is the actual founder of Neoplatonism. Ammonius was a charismatic teacher. He wrote no books and, with the aid of his pupils, kept his teachings secret after the manner of the Pythagoreans. Accordingly, we have no direct evidence of his philosophical beliefs. He was a mysterious figure, almost a cult-leader. He seems to have been able to form a mystical syncretism of Plato with Indian and Egyptian philosophies and theologies. We do know that two of his pupils were extremely important and brilliant philosophers: Origen and Plotinus. Origen was a Christian but Plotinus was not. From the fact that the writings of both Origen and Plotinus contain many references to Plato's dialogues and viewpoints, I infer that Ammonius Saccas must have been, in large measure, a Platonist. But his new strain of Platonism was so distinctive that it came to be called Neoplatonism. Hierocles affirms that Ammonius' aim was to reconcile the philosophies of Plato and Aristotle, and to combine mysticism with eclecticism. Nemesis, a Christian bishop and Neoplatonist of the late fourth century A.D., cites two teachings, which he declares contain the views of Ammonius. These teachings concerned the nature of the soul and its relation to the body; they were stated to be oral teachings only, since Ammonius was strongly opposed to making any written accounts of his beliefs.
Ammonius Saccas is reputed to be the first philosopher to employ the word theosophia, meaning "divine wisdom." He used this word to designate what he felt to be the essential teachings of the major religions of his time; these teachings became known as an "eclectic theosophic system." Ammonius, in his school, insisted upon strict moral discipline based on a mode of life that accorded with natural law; he strongly advocated exercising and purifying the mind by philosophical contemplation.
Porphyry, the most important student of Plotinus, in his book entitled On the Life of Plotinus and the Arrangement of his Work, says the following:
... At twenty-seven he [Plotinus] was caught by the passion for philosophy: he was directed to the most highly reputed professors to be found at Alexandria; but he used to come from their lectures saddened and discouraged. A friend to whom he opened his heart divined his temperamental craving and suggested Ammonius, whom he had not yet tried. Plotinus went, heard a lecture, and exclaimed to his comrade: "This is the man I was looking for."
From that day he followed Ammonius continuously, and under his guidance made such progress in philosophy that he became eager to investigate the Persian methods and the system adopted among the Indians. It happened that the Emperor Gordian was at that time preparing his campaign against Persia; Plotinus joined the army and went on the expedition. He was then thirty-eight, for he had passed eleven entire years under Ammonius. When Gordian was killed in Mesopotamia, it was only with great difficulty that Plotinus came off safe to Antioch. ...
In my view, the relationship of Plotinus to Ammonius is strongly reminiscent of the relationship of Plato to Socrates! Like Ammonius, Socrates (470-399 B.C.) left no written works; he was strictly an oral teacher. Also, both Ammonius and Socrates originally held relatively menial occupations. Ammonius was literally a sack carrier working on the docks of Alexandria, while Socrates was an Athenian stonemason.
The fact that Ammonius Saccas was initially a poorly educated and humble laborer on the docks of Alexandria, reminds me of the well-known American social philosopher, Eric Hoffer (1898-1983). Hoffer was initially a migrant laborer but finally became a longshoreman on the docks of Los Angeles. Like Ammonius, Hoffer had very little formal education; his education came from his life experiences not the classroom. The biggest difference between the two men was that Hoffer was the author of ten books while Ammonius wrote nothing. Both men were philosophers of the highest level; however; Hoffer wrote mostly about social issues while Ammonius mostly taught metaphysics.
Besides Plotinus and Origen the Christian, other disciples of Ammonius included Herennius, Longinus, Heracles the Christian, Olympius, Antonius, and a pagan also named Origen.
Fragments left from Porphyry's book entitled, Against the Christians, give details about the life and teachings of Ammonius. According to Porphyry, his parents were Christian, but upon learning Greek philosophy, Ammonius rejected his parents' religion and returned to paganism. However, the Christian historian Eusebius (263-339 A.D.) disputes this per the following quotation from his work entitled History of the Church (Book VI, Chapter 19):
... As an example of this absurdity take a man whom I met when I was young, and who was then greatly celebrated and still is, on account of the writings which he has left. I refer to Origen, who is highly honored by the teachers of these doctrines. For this man, having been a hearer of Ammonius, who had attained the greatest proficiency in philosophy of any in our day, derived much benefit from his teacher in the knowledge of the sciences; but as to the correct choice of life, he pursued a course opposite to his. For Ammonius, being a Christian, and brought up by Christian parents, when he gave himself to study and to philosophy straightway conformed to the life required by the laws. But Origen, having been educated as a Greek in Greek literature, went over to the barbarian recklessness. And carrying over the learning which he had obtained, he hawked it about, in his life conducting himself as a Christian and contrary to the laws, but in his opinions of material things and of the Deity being like a Greek, and mingling Grecian teachings with foreign fables. For he was continually studying Plato, and he busied himself with the writings of Numenius and Cronius, Apollophanes, Longinus, Moderatus, and Nicomachus, and those famous among the Pythagoreans. And he used the books of Chaeremon the Stoic, and of Cornutus. Becoming acquainted through them with the figurative interpretation of the Grecian mysteries, he applied it to the Jewish Scriptures. ...
... These things are said by Porphyry in the third book of his work against the Christians. He speaks truly of the industry and learning of the man, but plainly utters a falsehood (for what will not an opposer of Christians do?) when he says that he went over from the Greeks, and that Ammonius fell from a life of piety into heathen customs. For the doctrine of Christ was taught to Origen by his parents, as we have shown above. And Ammonius held the divine philosophy unshaken and unadulterated to the end of his life. His works yet extant show this, as he is celebrated among many for the writings which he has left. ...
Based on the above we have two major issues between Porphyry and Eusebius:
1) Was Ammonius a Christian or a pagan? Porphyry says he was a pagan; Eusebius demurs. Another Church Father, Jerome, in his work entitled On Illustrious Men (Chapter 55) says:
Porphyry falsely accused him [Ammonius] of having become a heathen again, after being a Christian, but it is certain that he continued a Christian until the very end of his life.
2) Did Ammonius the Neoplatonist write any books? Porphyry and Plotinus both indicate that Ammonius left no written works. Conversely, Eusebius asserts that Ammonius was celebrated for the writings that he left.
This confusion in identity may be due to the fact that Ammonius taught both Plotinus the Neoplatonist and Origen the Christian; later scholars on both sides wrote their own opinions about Ammonius, ignorant of the historical context in which the man lived. The Neoplatonist school of philosophy and Christianity, were diametrically opposed and constantly at war with one another, during the third, fourth and fifth centuries.
I have no opinion re the writing of any books, although I note that Pythagoreans were not supposed to put their more important teachings into writing. Also, in my view, it is very unlikely that the founder of Neoplatonic philosophy should have been at the same time a Christian. The unequivocal disagreement between Porphyry and Eusebius on these two important issues provides support for believing that there may have been two different men: Ammonius Saccas the Neoplatonist, and Ammonius of Alexandria, the Christian.
I have two other comments:
1) The Ammonius Crater on the Moon is named in his honor.
2) The Russian mystic, Helena Petrovna Blavatsky (1831-1891), called her system of teachings "Theosophy" - an ancient term first used by Ammonius Saccas. Blavatsky had a profound interest in both Neoplatonism and Gnosticism and both subjects are still studied by Theosophical groups around the world.