Well I think the fundamental issue is that it is impossible to rationally prove which values are more important than other ones. You have to almost arbitrarily

Well I think the fundamental issue is that it is impossible to rationally prove which values are more important than other ones. You have to almost arbitrarily decide. For example you could hypothetically design an artificial intelligence that is optimized for creating paperclips. As a person, you could decide your life goal is to drink as much glue as possible or something stupid like that. But since it goes against your survival instinct and cultural values (and everyone else's) you will just be a dysfunctional crazy person. Biologically you could define a "good" value system as one which is conducive to you having offspring. Ethics, morality, cultural values, etc. are not necessary for that although they might provide intellectual simplifications that help.