The spirit of the no-LW, OB, HPMoR rule is that the community shouldn't be quoting itself in quotes threads. That has a dangerous echo chamber-y feel to it.
Thanks. I didn't perceive that this was the spirit of the rule precisely because it was explicitly restricted to apply to writings from certain websites and ebooks. If the purpose is to ban quotes by (past and present) members of LessWrong, why not simply write, "No quotes by past or present members of LessWrong"?
Here's another installment of rationality quotes. The usual rules apply: