The rationalist community
Dated sources are over 18 months old; other dates are unknown.
Publication dates and source age
Sources counted: 2
Newest dated source: 2009-03-16
Assessed at this edition's evidence cutoff: 2026-09-15. 18-month boundary: 2025-03-15.
Some publication dates are unknown; the newest dated source may not be the newest source overall.
Publication age does not tell us whether a claim is still valid. Reading an old source again does not make its publication date newer. An update date does not establish that the passage we used was updated.
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In plain language
A community focused on improving how people form beliefs and make decisions; its label does not guarantee correct conclusions. [1] [2]
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Limits & distinctions
Self-identifying as a rationalist is not evidence that someone's conclusions are correct. Evaluate their reasoning and evidence. [2]
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A fuller explanation
In this context, people around a practice of improving beliefs and decisions. LessWrong distinguishes epistemic rationality (believing accurately) from instrumental rationality (acting effectively toward goals). [1]
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How it relates to the map
A reasoning aspiration does not determine values, political commitments, or a particular AI forecast. [1]
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Share this page
https://theaiatlas.org/ideas/rationality/
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Image previews are summaries. Keep the page link so readers can check the evidence.
Sources and what we read
1. What Do We Mean By Rationality?
Source is over 18 months old.
Publication dates and source age
Sources counted: 1
Newest dated source: 2009-03-16
Assessed at this edition's evidence cutoff: 2026-09-15. 18-month boundary: 2025-03-15.
Publication age does not tell us whether a claim is still valid. Reading an old source again does not make its publication date newer. An update date does not establish that the passage we used was updated.
Read the epistemic/instrumental distinction and discussion of Bayesian reasoning. A proposed practice, not a verified trait of participants.
2. Welcome to LessWrong!
Publication dates and source age
Sources counted: 1
Publication dates are unavailable.
Assessed at this edition's evidence cutoff: 2026-09-15. 18-month boundary: 2025-03-15.
Some publication dates are unknown; the newest dated source may not be the newest source overall.
Publication age does not tell us whether a claim is still valid. Reading an old source again does not make its publication date newer. An update date does not establish that the passage we used was updated.
Read the site's introduction and intended reasoning practice. Self-description does not certify participants' accuracy or common beliefs.
Edition and machine-readable evidence
Content version 0.20.0. Evidence cutoff 2026-09-15; this does not mean every source was read on that day.
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