LessWrong was founded in 2009 and relaunched in 2018 with a new codebase and full-time team.

We are a community dedicated to improving our reasoning and decision-making. We seek to hold true beliefs and to be effective at accomplishing our goals. More generally, we work to develop and practice the art of human rationality.[1]

To that end, LessWrong is a place to 1) develop and train rationality, and 2) apply one’s rationality to real-world problems.

LessWrong serves these purposes with its library of rationality writings, community discussion forum, open questions research platform, and community page for in-person events.

To get a feel for what LessWrong is about, check out our Concepts page, or view this selection of LessWrong posts which might appeal to you:

Check out this footnote[2] below the fold for samples of posts about AI, science, philosophy, history, communication, culture, self-care, and more.

If LessWrong seems like a place for you, we encourage you to become familiar with LessWrong’s philosophical foundations. Our core readings can be be found on the Library page.

We especially recommend:

Find more details about these texts in this footnote[3]

For further getting started info, we direct you to LessWrong’s FAQ. Lastly, we suggest you create an account so you can vote, comment, save your reading progress, get tailored recommendations, and subscribe to our latest and best posts. Once you've done so, please say hello on our latest welcome thread!


LessWrong FAQ

A Brief History of LessWrong


LessWrong Concepts

  1. Rationality is a term which can have different meanings to different people. On LessWrong, we mean something like the following:  

    • Rationality is thinking in ways which systematically arrive at truth.
    • Rationality is thinking in ways which cause you to systematically achieve your goals.
    • Rationality is trying to do better on purpose.
    • Rationality is reasoning well even in the face of massive uncertainty.
    • Rationality is making good decisions even when it’s hard.
    • Rationality is being self-aware, understanding how your own mind works, and applying this knowledge to thinking better.

    See also: What Do We Mean By "Rationality"?, Why Spock is Not Rational, What are the open problems in Human Rationality? ↩︎

  2. More sample posts from LessWrong:  

  3. More details about our core readings:

    Rationality: A-Z is a deep exploration of how human minds can come to under the world they exist in - and all the reasons they so commonly fail to do. The comprehensive work:

    The Codex collects Scott Alexander's writings on good reasoning, what we can learn from the institution of science, and the different ways society could be and has been organized. Exemplary essays include:

    Harry Potter and the Methods of Rationality started as a side project of Eliezer’s and grew to be one of the most highly rated Harry Potter fanfictions of all time and an an excellent primer on rationality. Eliezer imagined an alternate-universe Harry Potter who grew up with loving adopted parents, one of them an Oxford scientist. He enters the wizarding world with a scientific and rationalist mindset. Click here to read HPMOR through LessWrong or try the audiobook. ↩︎


14 comments, sorted by Highlighting new comments since Today at 12:18 AM
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I just stumbled upon lesswrong.com while searching for information on Zettelkasten and I must say this site is STUNNING! This is some of the most beautiful typography I've seen, anywhere! The attention to detail is exquisite! I haven't even gotten to your content yet! This will probably remain a permanently open tab in my browser... it's a work of art!

If you're interested in LW2's typography, you should take a look at GreaterWrong, which offers a different and much more old-school non-JS take on LW2, with a number of features like customizable CSS themes. There is a second project, Read The Sequences.com, which focuses on a pure non-interactive typography-heavy presentation of a set of highly-influential LW1 posts. Finally, there's been cross-pollination between LW2/GW/RTS and my own website (description of design).

Thanks to gwern for the mention of GW/RTS!

In the interests of giving equal screen time to the (friendly!) ‘competition’, here’s yet another viewer site for Less Wrong—one which takes an even more low-key and minimalist approach:


W-o-W!!! Thanks so much for these links!

Could you expand on what makes the typography noteworthy? I'm completely unaware of this topic, but curious.

Thank you so much. This website is amazing.

Hi all! I found my way here through hpmor, and am intrigued and a little overwhelmed by the amount of content. Where do I begin? The sequences? Latest featured posts? Is anything considered out of date at this point?

The sequences are still the place I would start. if you bounce off of that for any reason, I would start reading the content in the Codex, and then maybe give all the historical curated posts a shot. You might also want to try reading the essays that were voted as the best of 2018.

I will do just that. Thank you.

I came to a dead stop on these words, "We seek to hold true beliefs".  Beliefs are beliefs. If they were true, they would be facts. 

Also, "and to be effective at accomplishing our goals". What rational person doesn't? 

Facts are independent of beliefs, which is sort of their defining characteristic. But beliefs can be in alignment with the facts, or not; the goal is the former.

What rational person doesn't? 

None. But there are no such people in the strong sense, yet. This is the ambition of the project.

Please start using non-serif fonts for your online articles. They are impossible to read.

note: TAG's solution works for https://www.greaterwrong.com/, an alternate viewing portal for LessWrong, but not for LessWrong.com.

That said, I'm curious what devices you're reading it on. (some particular browsers have rendered the font particularly badly for reasons that are hard to anticipate in advance). In any case, sorry you've had a frustrating reading experience – different people prefer different fonts and it's a difficult balancing act.

Try the "grey" or "zero" themes, in the top left corner.