In general, it's not strange at all for A and B to both agree completely with C, but disagree with each other. For example, if C says "Pie is yummy!", B says "Pie is yummy and blueberry is the best!" and A says "Pie is yummy and cherry is the best!"
In this case, I disagree with your assertion that EY does not believe that Pebblesorter morality is inferior to human morality, an assertion fubarobfusco does not make.
I do think Eliezer is saying that Pebblesorter morality is inferior to human morality, specifically insofar as the only thing that "inferior" can refer to in this sense is also "h-inferior" — all the inferiorness that we know how to talk about is inferiorness from a human perspective, because hey, that's what perspective we use.
Today's post, The Bedrock of Morality: Arbitrary? was originally published on 14 August 2008. A summary (taken from the LW wiki):
Discuss the post here (rather than in the comments to the original post).
This post is part of the Rerunning the Sequences series, where we'll be going through Eliezer Yudkowsky's old posts in order so that people who are interested can (re-)read and discuss them. The previous post was Is Fairness Arbitrary?, and you can use the sequence_reruns tag or rss feed to follow the rest of the series.
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