How did people (anatomists, I guess) discover the functions of internal organs and hormones?

Question

I assume dissecting corpses helped in the research and discovery, but what about functions that require a living a specimen?

In: Biology

Answer 1

Almost every function was discovered by quite literally cutting humans open, looking what was there and then guessing. Later this was either confirmed or disproven.
Humans were cut open both dead (autopsy) or alive (vivisection).