If they were both conceptual beings, couldn't they argue about whether it "is right" to maximize pencils or paper clips?
They could, but they don't have to disagree about any observation to do that. 'Should' statements cannot be made from 'is' statements. Confusingly, 'is (morally) right' is a 'should' statement, not an 'is' statement.
Today's post, Moral Error and Moral Disagreement was originally published on 10 August 2008. A summary (taken from the LW wiki):
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