You (Eliezer) would break your word to save the world. It's just, if someone sufficiently rational came to you and told you about their biotech concoction, keeping your word is your best shot to save the world under UDT.
Of course, the guy you're quoting didn't understand UDT, so it would be perfectly understandable for him to use much the same reasoning and call it "honor".
When do UDT and honor yield different results?
Today's post, Prices or Bindings? was originally published on 21 October 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 Ethical Injunctions, and you can use the sequence_reruns tag or rss feed to follow the rest of the series.
Sequence reruns are a community-driven effort. You can participate by re-reading the sequence post, discussing it here, posting the next day's sequence reruns post, or summarizing forthcoming articles on the wiki. Go here for more details, or to have meta discussions about the Rerunning the Sequences series.