Only because they have compressed and encoded the entire sum of human knowledge at their disposal. There are models for everything in there, but they can only do what has been done before.
What's more amazing to me is the average human, only able to hold a relatively small body on knowledge in their mind, can generate things that are completely novel.
I hear this constantly. Can you produce something novel, right here, demonstrably, that an LLM couldnt have produced? Nobody ever can, but it’s sure easy to claim.
People assume training on past data means no novelty, but novelty comes from recombination. No one has written your exact function, with your exact inputs, constraints, and edge cases, yet an LLM can generate a working version from a prompt. That’s new output. The real limitation isn’t novelty, it’s grounding.