I'd also mention that I've been slowly working on a long-term project which is basically this scenario. It involves some of the followers of Epicurus interacting with Ashoka's Buddhist missionaries to create a new form of Buddhism. This has some similarities with how Mahayana Buddhism emerged in OTL (although appearing earlier), and also has some twists due to the interaction with Epicurean ideas. This starts to spread throughout the Greco-Roman world beginning in the early second century BCE. This eventually becomes the official religion of the *Roman Empire, at least for a few emperors (not necessarily for most of that history). This has the side-effect of butterflying away Christianity and then Islam, although Judaism survives and is if anything more diverse than in OTL, as some of the different beliefs in Judaism around the first centuries BCE and CE survive and spread.
This isn't being written quickly, mostly because I'm trying to tell the bulk of the tale through the various philosophical and religious writings which emerge in this timeline. That is interesting but slow to write, so this scenario is still a while away from finishing.
That sounds very interesting. I should like to read it when it's ready.
If definitely be interested in that as well.
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Would Buddhist monks and nuns be able to keep literacy to the same rate as Catholic monks did in OTL?