Just a few groups that have either aimed at similar goals, or have been culturally influential in ways that keep showing up in
these parts —
The Ethical Culture movement (Felix Adler).
Pragmatism / pragmaticism in philosophy (William James, Charles Sanders Peirce).
General Semantics (Alfred Korzybski).
The Discordian Movement (Kerry Thornley, Robert Anton Wilson).
The skeptic/debunker movement within science popularization (Carl Sagan, Martin Gardner, James Randi).
General Semantics is possibly the closest to the stated LW (and CFAR) goals of improving human rationality, since it aimed at improving human thought through adopting explicit techniques to increase awareness of cognitive processes such as abstraction. “The map is not the territory” is a g.s. catchphrase.