This page is open to edits from unaffiliated contributors, just click 'edit' at the top to get started.

The initial content for this page was provided by Chris Leong. Many concepts also came from Conceptually (archived), we'll move this notice to some sort of special thanks at the bottom of the page later.



Adequacy (archived)
Not missing any blindingly obvious opportunities to improve things significantly.

Affordance widths (archived)
The range of behaviour that people can engage in without bad results. Notes that this is different for different people and some people have no affordance width.

Alief (archived)
"Automatic or habitual belief-like attitude, particularly one that is in tension with a person’s explicit beliefs". Someone on a transparent balcony might know they are safe, but feel like they are in danger.

Anti-inductive (archived)
Something that becomes more complicated once people start to understand it (ie. the stock market, because quite quickly the rule for making money stops working or tactics in competitions)
Anti-prediction (archived)
A positive claim that doesn’t require much in the way of evidence once you’ve mapped out the probability space as it becomes clear that it is the most likely outcome.
Applause Lights (archived)
A statement that everyone can applaud because it is appeals to overwhelmingly popular principles or ideals, but which is essentially free of any concrete details that would give it actual substance.
If you don’t know if someone will do you a favour, should you ask on the basis that they can just say no or should you guess whether or not they would mind and only ask if you think they wouldn’t (also see Tell Culture (archived) - a culture where you explain your thought process) (Also compare to high-context vs. low-context cultures (archived))

Asshole filter (archived)
Setting up rules and then not enforcing them will encourage people to violate the rules and annoy the people who actually obey them at the favouritism
Attractor theory (archived)
A philosophy of action which suggests not merely optimising for utility/value, but also considering how your actions change you and your desires. The metaphor best describes short-term changes, but it can also be used to describe long-term changes ala. virtue ethics to an extent.


BATNA (archived)
Best alternative to negotiated agreement - always know the during a negotiation
Belief in belief (archived)
When you think you believe, but you actually don’t. If you actually believed it, you would act differently.
Black Swan (archived)
An event that is impossible to predict that is far beyond the norm
Broccoli Error (archived)
An error of thinking along the following lines, "But if I try broccoli again and find out that I like it now, then I’ll end up eating lots of broccoli and I don’t want to eat lots of broccoli"
Brown M&Ms (archived)
A test to make sure that people have read a document


Cached Thoughts (archived)
When someone gets an idea or response from someone else, but they didn’t actually create it themselves or ever subject it to critical analysis - it’s just there as ‘a possible idea or answer’ that they forget avoided this process. I do have some issues with this terminology - a cached thought sounds like something that you came up with and sounded reasonable at one time - but you never actually reconsidered.
Chesterton’s Fence (archived)
Argues that you should not be allowed to remove a law or custom until you know why it exists
Chicken and Egg Problem (archived)
Clearest example is a market in which you need buyers to get sellers, but you need sellers to get buyers. (Elizier calls this a Two-Factor Market)
Chinese Robbers (archived)
A fallacy where a person points out a huge number of examples and says that proves something about the group as a whole. For example, if one in a thousand Chinese people are robbers, you can pull out a million examples of Chinese robbers to appease the doubters
Clever Arguer (archived)
Someone who can argue incredibly persuasively for both sides of an issue
Common vs. Expert Jargon (archived)
Words designed to go mainstream vs. words designed to be used in a more formal setting
Competing Access Needs (archived)
Different people need different things. Instead of pretending that we can fulfil all needs and that other needs aren’t real, we need to accept this decide which needs we are going to prioritise.
Concentrated Benefits and Diffuse Costs (archived)
When a certain policy benefits a group of people strongly who are motivated to push for it, but has harms spread out over many people who are not incentivised to oppose it.
Co-ordinated Meanness (archived)
(vs. un-co-ordinated meanness). Sometimes you have to be "mean" in order to establish social norms, but you should be wary of taking unilateral action because it is less likely to be successful and if followed as a principle, many people or groups will take unilateral action based on their own highly subjective viewpoints.
Copenhagen Interpretation of Ethics (archived)
An interpretation of ethics where you become responsible for a problem as soon as you interact with it, even if you don’t make it worse or make it slightly better
Core competency (archived)
A unique skill or set of skills
Cost disease (archived)
Things getting more expensive without a clear reason
Counter-signalling (archived)
Signalling by not signalling, which indicates that you don’t have a need to signal
Crucial Considerations (archived)
Normal considerations would require you to make slight changes to your behaviour/worldview if true. On the other hand, crucial considerations would require a large shift in how we even think about the problem.
Crony Beliefs (archived)
Explains that some beliefs are treated differently than other beliefs, just as some employees may be treated very differently when cronyism is going on
Curse of Knowledge (archived)
The tendency of people to assume incorrectly that other people share the same relevant background knowledge (related to the Illusion of Transparency, but more specifically about knowledge)


Decentering Bias (archived)
A kind of thinking in which you are aware of biases, but in which you also check that they legitimately are biases
De Dicto vs De Re (archived)
"Jane wants to marry the tallest man in the country." De Dicto interpretation - wants the person she marries to satisfy the predicate (Don’t substituted). De Re: she wants to marry a person and that person satisfies that property (Are Substituted)
Deepity (archived)
Something that sounds deep because it has two meanings: one true but tautological or trivial, the other false but incredibly important if true
Dunbar’s Number (archived)
A suggested maximum number of people that someone can maintain stable relationships with
Doxa (archived)
Knowledge you know because you were told by someone else. For example reading in a book that the earth is round.


Episodic and diachronic (archived)
Episodic - when past you feels like a different person. Diachronic - when past you feels like the same person
Epistemic Learned Helplessness (archived)
When someone gives up on trying to discover the truth for themselves because it is too hard (also see clever arguers)
Evaporative Cooling of Group Beliefs (archived)
Terrible name but describes the tendency of groups to become more extreme when members are discouraged, as those who stay are generally more committed.


Fake Frameworks (archived)
Temporarily adopting a framework that you know isn’t true because you believe that it still contains some insights nonetheless.
Fallacy of Grey (archived)
Idea that because nothing is perfectly one way or the other it is all in-between with no difference. Just because something isn’t black or white, it doesn’t mean that it can’t be a different shade than other greys.
False Consensus Effect (archived)
People overestimate how many other people share their opinions
Founder Effects (archived)
The influence that the founder of a movement has on the way that things turn out
Fnords (archived)
Words that are primarily used to trigger a negative reaction in the reader whilst minimally adding to the content
Fox vs. Hedgehog (archived)
An allusion to, "The fox knows many things, but the hedgehog knows one big thing" (ie. ways of avoiding being hunted). Often applied to different writers/intellectuals
Free Floating Beliefs (archived)
The idea that we have evolved a bunch of beliefs that just work most of the time despite not standing on especially strong epistemic grounds (see also, metis). He also uses the term, "competence without comprehension"
Fuzzies (archived)
"A hypothetical measurement unit for "warm fuzzy feeling" one gets from believing that one has done good"


Generalising from One Example (archived)
Gish Gallop (archived)
Named after Duane Gish <https://www.wikiwand.com/en/Duane_Gish>Â (archived) to explain a strategy where a person throws out so many arguments and errors that the opponent has no chance of refuting all these arguments in the allotted time.
Goodhart’s Law (archived)
Once a measure starts being used for evaluation, it gets gamed
Guessing the Teacher’s Password (archived)
(A tendency). People are often taught in school that memorizing a phrase is equivalent to understanding and they often carry this habit with them through life.
Guilt Culture vs. Shame Culture (archived)
In guilt culture, your behavior is mostly motivated by an internal sense of morality, while in shame culture, your behaviour is motivated by maintaining the respect of the group.


Half a rationalist (archived)
(being one is dangerous) The idea that becoming incrementally more rational does not always make you better off as sometimes one bias is counter-acting another
Halon’s Razor (archived)
Never attribute to malice that which is adequately explained by stupidity
High Modernism (archived) Wiki (archived)
"excessive optimism in science and technology as means to reorder the social and natural world". This is often at the expense of local knowledge. SSC: "an aesthetic taste masquerading as a scientific philosophy… LARPing being rational by placing things in evenly-spaced rectangular grids"
Hofstadter’s Law (archived)
"It always takes longer than you expect, even when you take into account Hofstadter’s Law
Hype Cycle (archived)
A claimed standard progression of a technology


Idea Inoculation (archived)
Exposure to a weak and unpersuasive version of an idea makes it harder to persuade the person in the future
Ideological Bingo Games (archived)
When people stop listening to the other person and just look for particular words
Illusion of Transparency (archived)
Tendency of people to overestimate how well people understand what they are thinking (see Curse of Knowledge):
Double Illusion of Transparency (archived)
Belief that what you are saying is being understood and that you are understanding what you are hearing.
Incentive slope (archived)
 Behaviours that short term incentives push agents towards. Sometimes talking about incentives slopes instead of just incentives is helpful because the situation is such that the agent is likely to gradually progress along the slope, instead of immediately jumping to the end. It’s a pretty powerful visual metaphor.
Inferential Distance (archived)
How many ideas or concepts that you would have to explain first before explaining the concept that you would like
Inferior Equilibrium (archived)
When you are trapped at an equilibrium, but there an equilibrium that makes everyone better off.
Inside View/Outside View (archived)
Whether you make predictions using the specifics of the situation (inside view) or based on how similar situations turned out (outside view). The later is preferred when people give biased estimates using all the details available to them. The Outside View is also called reference class forecasting
Institutional Imperative (archived)
Covers institutional resistance to change, projects will appear to soak up any available funds, any idea the leader thinks up will soon be supported by studies, institutions will all copy each other
Isolated Demands for Rigor (archived)
Applying rather stringent demands for justification on things you dislike with and minimal demands on those you like.



Keeping your Identity Small (archived)
Recognising that having an identity limits your ability to think rationally.
Kolmogorov Option (archived)
In the face of ideological oppression, building up fortresses of truth in places the authority doesn’t care about or understand.


Law of Continued Failure (archived)
A situation where someone/some entity competent to course correct after an obvious disaster would likely be competent enough not to be in that situation in the first place
Least Convenient Possible World (archived)
The world which would be worst for the argument that you are running
Law of Equal and Opposite Hypocrisy
"When making a hypocrisy argument, people more often than not similarly ignore the equal but opposite hypocritical position they themselves are holding."
Legibility (archived)
The ability of the bureaucracy to understand a situation given its limitations which may include distance, a requirement for scientific understanding instead of metis and the necessity for large numbers of somewhat similar situations to be treated uniformly. Particularly used to criticise this understanding.


Map and Territory (archived)
Language and the way that we describe the world are separate from reality (also related to reification, which is treating an idea as more real or concrete than it actually is)
Memetic fitness (archived)
I agree with Ozy that this seems to have two separate definitions. a) How many people believe in an idea b) How many people talk about an idea.
Meta-Awesomeness (archived)
Being aware of your own faults in such a way that dealing with you becomes a much more pleasant to deal with (ie. if you can’t be awesome on an object-level, at least try to be awesome on a meta level).
Meta-contrarianism (archived)
Second-level of contrarianism in which someone is being contrarian to the contrarians (Scott splits it into uneducated, contrarian and meta-contrarian divide. This works a lot of the time).
Meta-Effects (archived)
(of an action) How taking a particular action changes you.
Metis (archived)
Greek for practical wisdom. Specialised, localised knowledge gained from experience or tradition or culture. Often people with metis cannot justify it in High Modernist terms.
Minimum Viable Product (archived)
A product with just enough functionality for people to want to buy or use the product.
Missing Stair (archived)
A problem that has been around for a while and which people have gotten used to working around, but then a new person joins and gets hit by it because no-one has explained it to them.
Moderator’s Dilemma (archived)
A situation where once you intervene, you are forced to decide whether or not you should intervene in all other situations within a large class. Ideally, you would like to just intervene in some cases, but this isn’t possible.
Moral Foundations Theory (archived)
Proposed by Jonathan Haidt. Suggests five foundations: Care/Harm, Fairness/Cheating, Loyalty/Betrayal, Authority/Subversion and Sanctity/Degradation. Argues that liberals concern themselves with the first two, while conservatives care about all five.
Moralist and the Revolutionary (archived)
The Revolutionary asks, "How can you improve human nature until you have changed the system?" The Moralist ask, "What is the use of changing the system before you have improved human nature?"
Motte and Bailey (archived)
A discussion in which a person makes a strong claim, but when attacked, they retreat to a much weaker and easier to defend claim, then later resume making the strong claim again
Mythic Values vs. Folk Values (archived)
What are the requirements to become a hero of a movement vs. the requirements to gain social status for an ordinary member of a group?
MTG Colors (archived)
A personality/values classification system based on the five types of magic used by Magic The Gathering card types. See associated post for more info.


Narrative Orientation (archived)
See: Narcissism
Narcissism (archived)
Telling a story about who you are and why your life is worthwhile.
Near-mode/Far-mode (archived) (Overcoming Bias link (archived))
People view things in near-mode if they affects them or a group they care about. People view things in far-mode they only affect things they don’t have an attachment to. In near-mode people expect emotional sensitivity for those affected, but in far mode things are more often romanticised.
Non-central fallacy (archived)
Treating a non-typical member of a category like all other members of that category
Noticing the Skulls (archived)
Being aware of the biggest and most obvious criticisms that a person could make of the community.


Observer Effect (archived) (also known as the Hawthorne effect)
One major issues with studies is when you observe people is that it changes their behaviour
OODA (archived)
Observe, orient, decide, act. Some call it NODA with the n standing for notice.
Optimiser’s Curse (archived)
If you pick the best option according to metrics, you are disproportionately likely to get the option where result was so high due to a measurement error.
Out to Get You (archived)
Describes situations when you are considering using a product or engaging in an interaction where the people or creators have interests that are fundamentally against your own, so you need to be wary of unexpected additional costs or consequences (alternative term: hostile)


Path Dependence (archived)
The idea that the history of a situation still affects how we do things now and perhaps even limits our options.
Phatic (archived)
Talking for the purposes of social interaction, rather than to convey information or ask questions
Porter’s Five Forces (archived)
Industry rivalry, threat of substitutes, bargaining power of buyers, threat of new entrants, bargaining power of suppliers
Post-Cynicism (archived)
The cynical view points at that the truth of a matter is not what we think, then the post-cynical points out that it is actually great that it happens that way (a.k.a. accepting the truths of the world explained by the cynical world view, then moving on from that)
https://www.ribbonfarm.com/2017/08/17/the-premium-mediocre-life-of-maya-millennial/ (archived) | Premium Mediocre]]
Something that is the best of the things that are mediocre, but which is still mediocre. Associated with maintaining an image of aspiring to more despite limited financial means, I would say for signalling your friends and family.
Pre-mortem (archived)
Imagine that the project you are working on failed and ask yourself, why did it fail? (Also known as a prospective retrospective)
Pretending to be Wise (archived)
Displaying neutrality or suspended judgement in order to signal maturity, wisdom, impartiality or just a superior vantage point
Principal-agent problem (archived)
When an agent is making decisions on behalf of a principal and they have incentives that differ from the principal.
Procrastination Equation (archived)
Motivation = (Expectancy*Value)/(Impulsiveness*Delay). Also known as Temporal Motivation Theory
Prickly and Gooey (archived)
Prickly people have solid, well-defined identities, while gooey are more flexible
Privileging the hypothesis (archived)
"Well... we have no idea who did it... no particular evidence singling out any of the million people in this city... but let's consider the hypothesis that this murder was committed by Mortimer Q. Snodgrass, who lives at 128 Ordinary Ln. It could have been him, after all."
Procedural knowledge gaps (archived)
Knowledge about how to do basic things that people have someone gone through their entire life without obtaining
Proving too much (archived)
When an argument doesn’t just prove its conclusions, but also other conclusions that are clearly false. Very similar to a proof by contradiction, but just has to lead to a conclusion that seems unbelievable, rather than an actual logical contradiction.
Pushing and Pulling Goals (archived)
Pushing goal - creating a plan and a structure to achieve a goal; Pulling goal - having a plan and a structure and trying to figure out what to do with it
Pre-rigourous/rigourous/post-rigourous (archived)
Particularly applies to maths. In the first stage you are taught the subject intuitively. In the second stage you are taught to prove everything and not take anything for granted no matter how obvious. In the third you reason informally, but with the ability to convert it into a formal proof.



Racehorse Paradox (archived)
The more players there are in a game and the greater the spread of the prize curve, the more risk you want to adopt
Reading Philosophy Backwards (archived)
Studying a lot of historic philosophical views seems kind of pointless because so much of what they say is either obviously wrong or obviously right. It becomes more useful once we use it to realise that a lot of our assumptions weren’t considered obvious at some point, which is why philosophers had to argue for them.
Red Team (archived)
An independent group that tries to test the defenses of the main group or provides independent criticism
Regulatory Capture (archived)
When the regulator works to advance business interests, rather than the public interest. Often occurs because the benefits are concentrated to a group with an incentive to lobby, whilst the harms are dispersed.
Reversing advice (archived)
If you are the kind of person who keeps hearing advice X, then this is likely because you are in a community that tends too much towards X and so you probably need to hear opposite-X


Sacred Values (archived)
When a value cannot be questioned without being seen as a character flaw and must constantly be signalled
Schelling Fence (archived)
1. "Slippery slopes can sometimes be avoided by establishing a "Schelling fence" - a Schelling point that the various interest groups involved - or yourself across different values and times - make a credible precommitment to defend." 2. A literal location which multiple reasonable actors settle on as a meeting place or gathering without coordinating to choose it.
Signalling Equilibrium (archived)
A situation in which a signal is considered valuable because all the best candidates work to obtain it and all the best buyers value it, so that no-one can switch unilaterally.
Signal Seeding (archived)
An explanation of how signalling comes about some of the time. At first a course of action might have a small signalling effect. People who care about sending this signal start adopting it for this effect, making the signal more reliable. The leads to more people adopting it, eventually this may even become a social norm where only the people who care least about this signal don’t take this course of action.
Slack (archived)
Having spare resources to be able to deal with unexpected future circumstances
Spoon Theory (archived)
A disability metaphor. It explains that some people have more energy/a greater ability to do things than other people and this can be affected by disabilities, chronic illness or psychological conditions.
Straw-Vulcan (archived) (TV tropes link (archived))
Someone who follows a very limited definition of what counts as "logical" and this being presented as what logic is.
Superweapons (archived)
Undermining someone’s credibility or reputation to the point where they lack the ability to defend themselves within society
Suspicious Convergence (archived)
If someone has a prior commitment to defend the value of X in order to achieve A, but argues this will also best achieve unrelated measure B, we might suspect bias. After all, most of the time, the best opportunity by two different metrics will be different.
Symbolic Orientation (archived)
See Narcissism


Taboo a Word (archived)
To restate something without using the word or any of it's synonyms.
Terminal vs Instrumental Values/Goals (archived)
Do we care about X in and of itself or as a means of obtaining A, B, C?
Toxoplasma of Rage (archived)
The idea that the rage of two groups can cause both to take action that grow the other (as well as themselves too when everyone feels that they need to pick a side)
Tragedy of the Anti-Commons (archived)
When there are numerous rights holders stopping a resource from being used
Tragic World vs. Horrid World (archived)
Are the problems in the world primarily the result of co-ordination problems/mistakes in how society is organised or is it a result of bad actors intentionally ruining things?
Trivial Inconveniences (archived)
Something small that nonetheless stops you from doing something important
True Prisoner’s Dilemma (archived)
A prisoner’s dilemma where you actually have 0 interest in the other person’s goals as opposed to the normal one where you probably do.
True Rejection (archived)
The reason why someone rejects what you are saying and not just the putative idea
Tyranny of Structurelessness (archived)
The way that even when a group is informally "structureless" structure still forms


Ugh-Fields (archived)
A reflex to flinch away from uncomfortable thoughts.
Umeshism (archived)
Statements of the general form: "If you’ve never missed a flight, you’re spending too much time in airports". Could also call it as Stiglerism <http://www.wired.co.uk/article/jordan-ellenburg> (archived)
Unambiguous First Mover (archived)
Obvious explanation that immediately pops into your head and stop you from engaging in further thought


Virtue of Silence (archived)
People notice what you do, not what you don't do. Often, the harm of an action can be caused just by discussing the possibility of taking the action. Therefore quite often morality requires you to maintain the Virtue Of Silence, a deliberate refrain from doing or publicly considering certain things even though no one will ever commend you for the effort.


Weak Men (archived)
Like a strawman, but not completely in that there are people who believe or act like that, but not very many
Weasel Words (archived)
Not a concept to stake to strictly, but words that are often much less meaningful than they seem. ie, "Critics claim", "A growing body of evidence"...
Weirdness Points (archived)
The idea that if you deviate from the crowd too much, then you'll just be a deviant. You have a set amount of metaphorical 'points' to spend advocating weird causes or ideas before people think you're a crank. For a 'rationalist', this means that part of evaluating an endorsement for a new way of doing things is considering how much credibility you'll have to burn to endorse something like the Squatty Potty (archived).
Winner’s Curse (archived)
The winner of an auction will tend to overpay as misjudging the value of the good makes you more likely to win the auction


X-Rationality (archived)
Extreme rationality. Scott Alexander defines this as:Â "techniques and theories from Overcoming Bias, Less Wrong, or similar deliberate formal rationality study programs, above and beyond the standard level of rationality possessed by an intelligent science-literate person without formal rationalist training."
X-Y Problem (archived)
When a person wants to achieve X, but they think they can do it if they know Y, so they ask about Y instead of X.