How does this specifically work? Wouldn't any decision about what training data to use be part of a "technique" in this sense? When Stable Diffusion didn't train on porn.

OTOH if the majority of your data is "bad" (maybe morally, but maybe not, maybe you are feeding in too much gibberish), won't that pollute your model?

You notice that X keeps telling you a WRONG physics equation. So, rather than "correct" it, you keep training until you see the output giving the RIGHT equation?

How could you know (in, say 1899) if the WRONG output wasn't quantum and the RIGHT output was classical?

I'm not sure I'm understand the distinctions here. In all cases, we are relying on the idea that it is easy to know what should count as "right"?