De'da may also be David Deutsch. Perhaps the two of them only recently split from each other...
In the comment thread to the next post, Eliezer says that Daniel Dennett was the intended interpretation, though he acknowledges that David Deutsch might also make sense after someone else suggests it.
Today's post, Where Physics Meets Experience was originally published on 25 April 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 Which Basis Is More Fundamental?, 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.