Creating a new intelligent species is not lightly to be undertaken from a purely ethical perspective; if you create a new kind of person, you have to make sure it leads a life worth living.
The unspoken bias here is that antinatalism (also an ethic) is not an ethic. Antinatalism says it is not ethical to create new life. Fine to disagree, false to say this ethic does not exist.
Antinatalism shouldn't be the perspective that it is unnecessary to ask the question of whether a new life is worth living, just the perspective that the answer is always "no." Eliezer isn't discounting this as a possible set of answers.
Today's post, Nonsentient Optimizers was originally published on 27 December 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 Nonperson Predicates, 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.