To make Wei Dai’s answer more concrete, suppose something like the symmetry theory of valence is true; in that case, there’s a crisp, unambiguous formal characterization of all valence. Then add open individualism to the picture, and it suddenly becomes a lot more plausible that many civilizations converge not just towards similar ethics, but exactly identical ethics.
I’m immensely skeptical that open individualism will ever be more than a minority position (among humans, at least) But at any rate, convergence on an ethic doesn’t demonstrate objective correctness of that ethic from outside that ethic.
To make Wei Dai’s answer more concrete, suppose something like the symmetry theory of valence is true; in that case, there’s a crisp, unambiguous formal characterization of all valence. Then add open individualism to the picture, and it suddenly becomes a lot more plausible that many civilizations converge not just towards similar ethics, but exactly identical ethics.
I’m immensely skeptical that open individualism will ever be more than a minority position (among humans, at least) But at any rate, convergence on an ethic doesn’t demonstrate objective correctness of that ethic from outside that ethic.