I don't understand what this is about now. I understand in this fragment you are discussing why can't we make pain go completely away at will, and why didn't ev

I don't understand what this is about now. I understand in this fragment you are discussing why can't we make pain go completely away at will, and why didn't evolution invent such a thing. Among the causes you don't consider is this not being beneficiary overall, or not being "a simple mutation away" at any point of our evolution so far, both of which are perfectly feasible explanations.