Ada Palmer explains how epistemology actually works (read the whole thing):
So if you were writing a preface to Epictetus, you would write a preface that said “He was a pagan, but he was almost as good as St. Paul!” And then ten years later when there was a new edition and someone wanted to make that edition sound better, and I have all of these editions in Latin and I have the article version of this where you can read the translations of all of these, they’ll say they want to make a stronger claim, so they’ll say “Epictetus’s moral maxims are barely less good than St. Paul’s.” And the next one will say “Epictetus’s moral maxims are just as good as St. Paul’s!” And the next one will say “Epictetus’s moral maxims, even though he was a pagan, were even better than St. Paul’s, because they are simpler and clearer and more effective at teaching ethics.” And by the time you get to the 1700s there’s an edition, which you can tell is copied from these earlier editions, they even plagiarize sentences from each other’s prefaces, it’s direct evolution, that says “Epictetus by the light of Reason alone and without the necessity of scripture or revelation arrived at better ethics than St. Paul.” And that is the kind of book that Voltaire owns when he is a kid.
and brings it up to date:
Real changes in what a society thinks, in what a culture values, come from thousands of people debating something. It comes from that classroom where people are talking about Epictetus. And the modern equivalent of that classroom where people are talking about Epictetus then is this talk, this convention, blogs and social media spaces, even Twitter, anywhere where people are talking about books and events and thoughts. What’s going to shape the future? It’s people online debating about which actions are ethical or unethical in Game of Thrones. That’s exactly like these classroom discussions of Epictetus, which turn into introductions to Epictetus, which turn into the education of Voltaire, which turn into the pen mightier than all swords. Random conversation is where it happens, not one genius, thousands of people exchanging ideas. And it doesn’t result in the world those people envision. Renaissance people did try to intentionally re-engineer the world, and they did sort-of have a shared plan, they wanted to make a world that was more ethical, that had a lot of moral education of its elites in those values which both Ancient Rome and Christianity shared, and this would result in an era of peace.