Matt Quinn said:
With the Arabs, it was Islam the united them and sent them surging across North Africa and into Spain (the west) and into Persia and India (the east), creating a huge (and for a short time, unified) empire. Large empires typically tend to be free-trade zones, and since the Arab conquest put an end to the perpetual wars between Byzantium and Persia, peace enabled people to concentrate on other matters.
On the matter of Christianity, the Judeo-Christian God is far less capricious and arbitrary than various pagan gods (incl. Odin, who often killed his own followers, or the hypocritical sex maniac Zeus). The notion of a set series of laws rather than the whims of a deity that often changes its mind surely resembles the laws of nature, yes?
These areas were still Christian, though they rejected the authority of the Roman Pope. Many of the great scientists like Newton and Pascal were Christians too.
The Nestorian Church of the East (wrongly viewed by most modern-day Christians as "heretical") was renowned in Central Asia and various other places as a provider of doctors. That doesn't seem "anti-science," now does it?
The notion of a single power ruling over the universe already existed in the Pagan period, among both Stoics and Neoplatonists. The idea that the universe was governed merely by divine whim was already fading by the Hellenistic, and was quite dead during the Roman period. Moreover, there were equlivalent concepts in the vast majority of Pagan religions. A universal law is very important, for example, to Sophocles and other Greek dramatists. Likewise, the concept of the universe as _cosmos_, an orderly whole, was central to Greek thought even before that. The idea had lost much importance due to the evolution of Greek religion, which was much influenced by Middle Eastern forms of ploytheism in which divine whim was very important. But even here, we should be careful. Mesopotamiam Paganism, for example, had enough of a concept of cosmic order to invent astrology.
In most forms of Indo-European religion concepts of cosmic law are of central importance, ranging from the early Celtic concept of wirjânjâ, to the Hindu idea of dharma. The idea of a mighty and just sky-God enforcing cosmic law, justice, and an orderly nature is central to Indo-European spirituality.
Science arose due to a wide variety of factors. The revival of Classical scholarship was one. Though this was helped along by the Scholastics, it was not created by them, and in various ways the Scholastic approach hindered scientific progress. An emphasis on practical, empirical research also played a big role. With the exception of a few mavericks like Archimedes, Greco-Roman thinkers really were mostly engaged in a kind of parlor game. This had very little to do with Paganism, but a great deal to do with a slave economy. By contrast, a good number of medieval thinkers were seeking solutions to practical problems. Gunpowder also played a role. Much of modern mathematics was invented by engineers trying to aim primitive cannon. Their work then became absolutely essential to science. The spread of Indian/Arabic numerals was also vital. Without decimal numeration, the kind of detailed mathematical description of phenomena that is the hallmark of scientific thinking would have simply been impossible. Finally, improved technology also played a huge role. Without better glass and improved grinding methods, neither the telescope nor the microscope would have been made.
Christianity played very little role in this process, either for bad or for good. In the late Roman period, it was responsible for the closing of numerous institutions of learning (all of the major institutions of higher learning, actually), and the destruction of many works of scholarship. However, it is rather doubtful that the lack of this destruction would have triggered an earlier scientific revolution. Nor, given the economic, technological, and social realities of the time, is it likely that a scientific revolution would have been possible for centuries after the fall of Rome. The Church, both Catholic and Protestant, did at times persecute learning through the Middle Ages into the early modern period, but was largely ineffective. Giordano Bruno, for example, died at the stake, yet his ideas continued to be read. Likewise, the Church silenced Galileo, but only after his major discoveries were made. A lack of Church persecution might have allowed a Scientific Revolution some decades of advancement over OTL, but probably not anywhere near a century.
The efforts of the Church to support learning largely just replaced secular efforts that had existed before. Church scholars, important as some were, would almost certainly have been replaced by secular scholars or those associated with various philosophical schools. The Church was important in the spread of literacy, and might here have made a genuine contribution. This, together with the importance of healing in the Christian tradition, explain the Nestorian doctors. Another genuine contribution was in the development of clockwork to mark the canonical hours. This, however, may be greatly overstated. A good deal of evidence has surfaced that the Romans, at least, and probably the Greeks before them, had a much better understanding of clockwork than we have previously thought. If so, than the idea of a clockwork universe would have been entirely possible to derive in a Pagan context.