Today's post, Entangled Truths, Contagious Lies was originally published on 15 October 2008. A summary (taken from the LW wiki):

Given that things are often entangled with other things in ways which we do not know, it is really really difficult to tell a perfect lie.

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 Ends Don't Justify Means (Among Humans), 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.