Write the decision, counterevidence, alternative hypothesis, failure condition, and next action. Drafts stay in your browser.
Audit a real decision →
Your brain edits reality.
Learn the patterns. Check the evidence.
Make a clearer move.
Three thinking patterns to see differently
From glossary to decision system
Recognize → Test → Counter → Decide.
The library still explains cognitive biases, effects, heuristics, and related phenomena. The newer layers help you use that knowledge without pretending a label is a diagnosis.
Start from work, forecasting, or AI-assisted decisions when you do not already know the name of the relevant pattern.
Browse decision contexts →See boundary conditions, contested findings, reviewed sources, and where the quick definition needs qualification.
Check the evidence layer →Separate patterns that are easy to confuse, such as hindsight versus outcome bias or outcome bias versus moral luck.
Compare nearby concepts →215canonical entries
36evidence-reviewed
13mechanism families
LocalDecision Audit drafts
Start from a real situation
Decision guides for the questions people actually have.
Use a guide when you know the problem but not the bias name. Each one combines a small set of reviewed lenses with a concrete workflow.
AI-assisted decisions
Use these evidence-reviewed lenses when a chatbot, model, recommendation system, or automated decision aid is influencing what you believe or do.
Use this guide →Project estimation & delivery
Use these evidence-reviewed lenses when setting a deadline, estimating effort, discussing delivery risk, or learning from a project that finished later than expected.
Use this guide →Checking claims & misinformation
Use these evidence-reviewed lenses when deciding whether a repeated claim is trustworthy, checking a correction, or testing an explanation against plausible alternatives.
Use this guide →Comparing plans & pricing
Use these evidence-reviewed lenses when comparing subscription tiers, product plans, vendor offers or recommendation menus where the way options are arranged may change what looks attractive.
Use this guide →A public knowledge library
Put a name to the shortcut before it makes the decision for you.
Browse the library by concept, then go deeper where we have reviewed the evidence. Older entries stay visible while we improve them, rather than pretending the whole collection is equally certain.
Decision MakingAction Bias – when taking action feels better than doing nothingthe tendency to act in any situation, even when inaction would be more effective.Read entry Attribution BiasActor-Observer Bias – when you blame circumstances for yourself but personality for othersthe tendency to blame our own behavior on external circumstances while attributing others’ actions to their personality.Read entry Decision MakingAdditive Bias – when you add instead of subtractingthe tendency to solve problems by adding new elements, even when removing something would work better.Read entry False PriorsAgent Detection Bias – when you see intention behind randomnessthe tendency to see intent and intelligence behind random events, even when there’s no real agent involved.Read entry Prospect TheoryAmbiguity Effect – when you avoid the unknown, even if it might be betterthe tendency to avoid options where the probability of success is unknown, even if they could be better.Read entry Cognitive BiasAnchoring Effect – when a starting number pulls later estimates toward itAnchoring Effect is the tendency for an initial number or reference value to pull a later numerical judgment toward it, even when the starting point is weak or not very useful.Read entry
Built for reflection, not certainty
Learn the names and patterns behind common thinking traps.
See concise examples of how a bias can influence everyday judgment.
Use practical countermeasures as a prompt to pause, seek evidence, and reconsider.
What we are building
A growing guide to what we know, what is debated, and what is worth checking before a decision.
Practice Lab
Knowing the name is not the same as spotting the question.
Practice matching decision checks to evidence-reviewed cognitive-bias lenses.
Work & project decisions
6 short exercises with evidence links.
Forecasting & future choices
6 short exercises with evidence links.
AI-assisted decisions
6 short exercises with evidence links.
Decision Skills
Knowing a bias name is not the same as making a better decision.
Build practical skills that connect evidence, decision contexts and short exercises.
Evidence evaluation
Judge whether a claim deserves confidence before repetition, fluency or preference turns into evidence.
Decision making under uncertainty
Make useful choices when outcomes are not known and one number, story or recent event can pull judgment too strongly.
Forecasting
Estimate what may happen next by using comparable evidence, explicit uncertainty and records made before the outcome is known.
Cognitive biases in everyday life
Start with a question you have actually had.
Why do bad projects survive? Why does repeated news feel true? Why can an AI estimate pull your own estimate toward it? Read the situation first, then follow the evidence.
Money & Shopping
Why the First Price You See Changes What You Will Pay
A first price can quietly become a reference point, so a later price feels cheap or expensive in comparison instead of on its own.
Work & Career
Why Bad Projects Are So Hard to Stop
Past effort can make a weak project feel too expensive to abandon, even when the next step no longer makes sense.
News & Internet
Why We Keep Finding Evidence That We Are Right
Once we prefer an explanation, it becomes easy to search for supporting evidence and much harder to notice what could prove us wrong.
AI & Decisions
Why an AI's First Answer Can Shape Your Judgment
An AI estimate can become an anchor before you have formed your own view, making later reasoning orbit around the model's first number.
Experiments Lab
Change one detail. See whether the judgment moves.
Run short, private demonstrations of anchoring, framing, choice architecture and decision review. Nothing is uploaded.
Numbers & Estimates
Does the First Number Pull Your Estimate?
Try two versions of the same pricing question and see why a starting number can pull later estimates toward it.
Framing
Does Survival vs Mortality Wording Change the Feeling?
The numbers stay identical while the wording changes from survival to mortality. Notice whether your evaluation moves with the frame.
Choice Architecture
Can a Third Option Change Which Plan You Prefer?
Choose between two plans, then compare the same choice after a clearly weaker third option appears.
Cognitive Bias Observatory
How is the information environment framing the same topic?
Track gain and loss frames, certainty, salience, authority cues and repeated wording with transparent rules and source provenance.
Use the knowledge
From bias names to reusable decision tools.
Lens packs turn reviewed concepts into short workflows for real tasks. The AI-era Bias Lab tracks newer human–AI interaction patterns as research questions instead of declaring every interesting effect a new bias.
Career, AI work, teams, projects and information checking.
Use a lens pack →Anchoring loops, sycophancy, offloading, source memory and new testable hypotheses.
Explore the lab →Decision workbench
Use the library on a real decision.
Review a career choice, build a reusable lens pack for a team, or follow AI-era research from an idea to a reproducible result.
Compare options, preserve an independent estimate, challenge the favourite and define a reversible test.
Review a career decision →Create a compact checklist from published lenses for a recurring work decision.
Build a lens pack →See which human–AI ideas have only a hypothesis, which have a protocol and what would move them forward.
Track the research →Open research
Our first preregistered human–AI pilot.
Instead of adding another catchy AI-bias label, we are testing one concrete prediction: whether seeing standardized AI advice before an independent estimate changes the final numerical judgment.
Start with a real decision
From bias names to a decision you can inspect.
Choose a situation, identify missing evidence, use a few relevant lenses and finish with a practical next action.
Hiring, estimation, incidents, AI research, vendor selection, negotiation and more.
Start from a situation →Independent estimates, outside view, decision journals, red-team review, source tracing and more.
Browse techniques →