I believe the problem with this, is that you have given actual values (pain units), and equated the two levels of "torture" outlined in the original thought experiment. Specifically, equating one trillion humans with dust speck in eye and Alice being tortured.
So, what's the problem? Is a dust speck incomparable to torture? A dust speck is comparable to something slightly worse than a dust speck, which is comparable to something slightly worse than that, etc. At some point, you'll compare dust specks to torture. You may not live long enough to follow that out explicitly, just like you could never start with one grain of sand and keep adding them one at a time to get a beach, but the comparison still exists.
Today's post, Torture vs. Dust Specks was originally published on 30 October 2007. 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 Motivated Stopping and Motivated Continuation, and you can use the sequence_reruns tag or rss feed to follow the rest of the series.
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