We have a pretty good grasp of TES lore as people looking from the outside in, but what is lore to the peoples of Tamrial and beyond?

We can read Vivec's sermons and teachings, but are the concepts of CHIM well understood among the Dunmer people? Are there any individuals out there actually attempting to achieve CHIM? How did Talos learn of CHIM?

How many know about mantling? Why are most cases of mantling we know of it seems like the manteler isn't fully aware that they're doing it (that or we just don't know anything about that person)?

Are there groups that understand that many of the pantheons are not just the same beings (I know they realize that part), but different aspects of Lorkatosh?

Some know that Malacath is Trinimac, but do they ever seek to ask him about Auri El and Shorkhan?

We know that Ocato knows about the Tower and I, we also know the Thalmor know about Towers, but is all this information secret? Do other mages an scholars know about it?

It just seems that the citizens of Tamrial that we've met are, well, dumb. They are completely unaware of the various events of mythic importance transpiring around them. Even the mages seem far to focused practicing casting candle light on themselves to realize that the person they just talked to might just be an aspect of a dead god.

The only person I can remember meeting who seemed to know any of these things was Martin Septim. But did he know about mantling and other things because of his research, or simply from divine insight from being a Septim?

I doubt that many in Tamriel have any understanding of metaphysics, the same as in the real world. There are probably a handful of priests on the Summerset Isles, in House Telvanni, and (formerly) in the Tribunal Temple who understand the Endeavor/CHIM.

Knowledge of mantling seems slightly more common, as at least some people would understand that's how Talos achieved godhood. Not just because he's awesome.

I suppose most people would consider their own pantheon to be the only true pantheon, with the others being false gods. Or else, they would view their own religion as the truth and the others as misguided worship.

As for assigning normative judgments to them, like "dumb," I don't think that's fair. Most people in the real-modern world have very poor knowledge of physics, politics, comparative religion (even if they know their own), and other such topics. People are simply too busy with every day life for everyone to be able to care about that kind of thing. It requires a certain amount of wealth and privilege to have access to that information as well as the free time to think about it.

Take that problem and import it to feudal type society and you compound the problem.

http://www.imperial-library.info/content/minutes-lusty-argonian-historical-society

It let think that apart from some extremly learned person, most of the TES people know less thing about lore than us. At least on the "obscure lore", because some of them would probably know much more about history, geography... than we do.

Good point. That's an important distinction.

SInce these days there are people arguing that the Dragonborn has to be a Nord and that a non-Nord can't learn the Thu'um, having a source where a Nord says she knows of no reason why any other race can't learn the Thu'um, I agree.

Prince Attrebus in The Infernal City, at least, is aware of the function of the towers (that they hold the world up and keep it from dissolving back into Oblivion), and attributes this knowledge to one of his lessons growing up. So most of the nobility and scholar class are probably familiar with the basic concepts, even if they aren't aware of the specific metaphysics at work.