WIY: My point exactly. You know that because you can see it in the Gemara. She doesn’t because she can’t.
Ben Levi: That is a gross misrepresentation of the Rambam’s opinon. He says that it’s Assur to follow Chazal in medicine because they only knew what was known at their time and that following such medicine is actually Assur because it’s Sakanas Nefashos.