> They don't really know if they're right.

Neither do humans who have no access to validate what they are saying. Validation doesn't come from the brain, maybe except in math. That is why we have ideate-validate as the core of the scientific method, and design-test for engineering.

"truth" comes where ability to learn meets ability to act and observe. I use "truth" because I don't believe in Truth. Nobody can put that into imperfect abstractions.

I think my last paragraph covered the idea that it's hard work for humans to validate as it is, even with tools the LLMs don't have.