Philosophy newbie here!
I was reading up on the very basics on ethics and the division to normative and descriptive struck me as odd.
From biological viewpoint the fundamental nature of this field seems much like upside-down mathematics: derivation from axioms vs discovery of axioms (=core values?) – "if you ask why long enough you arrive at 'just because'". Or alternatively, setting up (or describing) fundamental goals or valuation systems based on what satisfies the part of our brain that evolved to help us team up and survive as hunter-gatherers. Then building on top of that – describing derived goals or valuation systems on how to reach the axiomatic goals efficiently.
Is the nature of normative ethics the author prescribing their personal axioms (=descriptive ethics with n=1)? Does the field as a whole have a shared set of axioms and normative ethics argues over how to reach those efficiently? If so, is it to draw first level derivates from the descriptive side from sort of a popular vote and use those as a goal (with the sole axiom being to draw from descriptivism)? If so, to what extent are the conclusions universal versus a reflection of the author's time and society?
PS. This might be a stupid question in the sense that it's probably well covered in the literature, but was unable to find an answer with reasonable effort. Any recommended reading or general insights?