Rationalist community

The rationalist community is a 21st-century movement that formed around a group of internet blogs, primarily LessWrong and Astral Codex Ten (formerly known as Slate Star Codex). The movement initially gained prominence in the San Francisco Bay Area. Its members seek to use insights from various academic fields (such as epistemology, probability theory, and psychology) and awareness of cognitive biases to achieve both epistemic rationality (coming to true beliefs about the world) and instrumental rationality (acting in a way to achieve one's objectives). Heavily overlapping communities include effective altruism, transhumanism, and AI safety (specifically mitigation of AI extinction risk). The borders of the rationalist community are blurry and subject to debate among the community and adjacent groups. Members who diverge from typical rationalist beliefs often self-describe as "rationalist-adjacent" or "post-rationalist" (also known as "ingroup" and "TPOT", an acronym for "this part of Twitter").