Even before the Council of Nicaea, Donatists were crushed by Constantine. So, the Nicene Creed dealt mostly with Arianism, a name originating from the Christian presbyterian Arius. Arianism is a non-Trinitarian Christological doctrine which asserts the belief that Jesus Christ is the Son of God who was begotten by God the Father at a point in time, a creature distinct from the Father and is therefore subordinate to him, but the Son is also God, i.e. called God the Son.
Also, he enforced the Nicaea Council’s recommendation on prohibiting the celebration of the Lord’s Supper on the day before the Jewish Passover, which marked a definite break of Christianity from the Jewish tradition. But, Jews were not considered pagans by his laws. Even though it was made illegal if Christians were affected by Jewish, such as by seeking converts, by attacking other Jews who had converted to Christianity, by owning Christian slaves, or by circumcising their slaves, Jewish clergies were given the same exemptions as Christian clergies.
Even with these strong Evicts of Constantine the Great, Epicureanism had permeated deeply in the public in the late classical period, chiefly because of the Epicurean motive of the pursuit of happiness. So, there was a strong need to suppress the pagan belief of Epicureanism.
In the early Byzantine Empire in Alexandria, three or four generations after Constantine, there was an influential and beautiful Hellenistic, Neoplatonist philosopher Hypatia (350–370 ?–415) whose father Theon (c. 335–405) was a mathematician. She used to ride a chariot in the city in a philosopher’s cloak tribon. In her own lifetime, Hypatia was renowned as a great teacher and a wise counsellor, and many came to her to learn the works of Plato and Aristotle.
As recently as 1996, there was big news about Wiles’s proof of Fermat’s last theorem that x3 + y3 = z3 does not have integer solutions. This equation is a Diophantine equation discussed in Arithmetica authored by Diophantinus (201–215 to 285–299) of Alexandria, about one and half centuries before Hypatia. In 1637, Pierre de Fermat wrote in the margin of a copy of Arithmetica that he found a truly marvellous proof of his last theorem, but that the proof was too large to fit in the margin. Hypatia is known to have written a commentary on Diophantus’s 13-volume Arithmetica. This item alone can show that the Neoplatonist Hypatia was an influential mathematician, astronomer, and philosopher. But, in her lifetime, Neoplatonism was not embraced by Christianity. During the religious feud in Alexandria, four generations after the Nicene Creed, Serapeon (the temple of Greek–Egyptian Jupiter as a means to unify the Greeks and Egyptians) was destroyed. The Serapeon in Alexandria had the second-best collection compared to the Museum of Alexandria, containing a half million papyrus rolls in its peak. With the Serapeon gone, the written pagan knowledge also disappeared. During this chaos, Hypatia was murdered by a mob of Christians led by a lector named Peter in March 415. Hypatia’s murder shocked the Empire and transformed her into a “martyr for philosophy”, and her father’s student Damascius became increasingly fervent in his opposition to Christianity. Damascius (c. 458–after 538), born in Damascus of Syria and known as “the last of the Neoplatonists,” was the last scholar of the School of Athens. He was one of the pagan philosophers persecuted by Emperor Justinian I in the early 6th century. Among the disciples of Damascius, the most important are Simplicius who was mentioned as the celebrated commentator on Aristotle in Chapter 1. Some modern scholars consider that the legend of Saint Catherine of Alexandria was probably based on the life and murder of Hypatia, with reversed roles of Christians and pagans after embracing Platonism in Christianity in the Middle Ages. But, Neoplatonists in Alexandria at that time were pagans. In any case, our information on the Greeks’ atom has a lineage Democritus–Epicurus–Aristotle–Lucretius–Hypatia–Simplicius.
The downfall of the statue of Serapis at Serapeon of Alexandria in 415 was lamented by poet Palladas as the end of way of life in the Epicurean ‘Gardens’, and the murder of the intellectual Hypatia was a precursor of the death knell for the whole pagan tradition, which was finally terminated by Emperor Justinian in 429. With the Eviction, other paganisms, including Stoicism and Scepticism, were also driven out. Stoicism was started by Zeno of Citium (c. 334 BC–c. 262 BC) in Athens in the early 3rd century BC, and the Stoics were taught that “virtue is the only good” for human beings, and that external thing — such as health, wealth, and pleasure — were not good or bad in themselves. According to Stoicism, the path to happiness for humans is found in accepting the moment as it presents itself, by not allowing oneself to be controlled by the desire for pleasure or fear of pain, exactly the opposite way of Epicureanism. As Neoplatonism was evicted, so was Stoicism. The virtue of Stoicism is similar to that of Platonism, and the stoic attitude was installed in the monasteries in the Middle Age. Scepticism is an attitude where one shows doubt whether something is true or useful. Radical forms of scepticism deny that knowledge or rational belief is possible, and urge us to suspend judgment on many or all controversial matters. More moderate forms of skepticism claim only that nothing can be known with certainty, or that we can know little or nothing about the big question in life, such as whether God exists or whether there is an afterlife. Religious scepticism is “doubt concerning basic religious principles such as immortality, providence, and revelation”. The 13th-century saint Thomas Aquinas (1225–1274) stated on the creation in Genesis: “With respect to the origin of the world, there is one point that is of the substance of the faith, viz. to know that it began by creation,” and the Roman Catholic Catechism3 published in 1566 placed “belief” in the first place. Scepticism was evicted along with the other paganisms in 429.
Along with Epicureanism, Neoplatonism, Stoicism, and Scepticism, Totemism and Animism also belonged to the evicted paganisms. Along with Animism, Totemism was the earliest form of belief worshipping a sacred object, or symbol that served as an emblem of a group of people, such as a family, clan, lineage, or tribe. Animism derived from Latin anima (meaning breath, spirit, and life) is the religious belief that objects, places, and creatures all possess a distinct spiritual essence. There is some common ground in Totemism and Animism.
By the early 5th century, what mattered most were the logical philosophies from the classical Greek period. Stoicism was practiced by monks in the monasteries sprawling after the Justinian Evict. Thus, as in most cases — Heaven and Hell, Sun and Moon, North and South, plus and minus, good and bad, love and hate, freedom vs. equality, Republican vs. Democrat, particle and wave — there remain two dominating pagans from Greek philosophies: Epicureanism and Neoplatonism. As John Vergados commented, Romans the excellent soldiers wanted some philosophy from Ancient Greeks.
Epicureanism aims at the pursuit of happiness, and Neoplatonism aims at the pursuit of virtue. Which was chosen by Romans?
Cicero’s epigram nihil est virtute pulchrius (there is nothing more beautiful than virtue) morally resonates in our ears, and Thomas Jefferson’s insertion “pursuit of happiness” in the Declaration of Independence is recited over and over again. It must have been difficult to favour one over the other. To Christians, both were pagans. Then, they looked for a possibility of changing the way of practicing. To Epicureans, all were materialistic and God was not acceptable by definition. They did not view the world in the way of Empedocles that even if gods existed they do not interfere the humans. Epicureans were useless to Christians.
In the 5th century, the greatest Christian Father Saint Augustine (354–430)