What distinguishes a person from any other computation
A person is reflectively self aware.
and why does that particular distinction carry so much moral weight?
Evolution built me to care about humans, and upon reflection, the values I have include non-humans who have features like being reflectively self aware.
There's also Hayekian arguments-- self-aware agents are apt to accumulate information about their own desires and activities. Systems which allow that information to have an effect seem to be more capable.
ETA: There is now a third thread, so send new comments there.
Since the first thread has exceeded 500 comments, it seems time for a new one, with Eliezer's just-posted Chapter 33 & 34 to kick things off.
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