Another possibility: Eliezer does not want the meme to be associated with LW. Because, even if it was written by someone else, most people are predictably likely to read it and remember: “This is an idea I read on LW, so this must be what they believe.”
Another possibility: Eliezer does not want the meme to be associated with LW. Because, even if it was written by someone else, most people are predictably likely to read it and remember: “This is an idea I read on LW, so this must be what they believe.”