Can someone with more knowledge help me with this silly question in my head? >>Along the way, it wrote 13 million lines of Lean and proved 29,500 intermediate theorems Did a human check the 13 million lines of code? How does QA'ing this type of work works?
The point of writing Lean code is that Lean checks it accordingly. Lean is a domain specific language to encode mathematical reasoning in a way that can’t be fooled. Note to other users: don’t downvote this kind of comment, answer it.
encode mathematical reasoning in a way that can’t be fooled.
I would be a bit careful asserting that in full generality, given https://github.com/James-Hanson/junk-theorems-in-lean