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The Incentives Lab
Mental Models · Social

Common Knowledge

Information that everyone knows, and everyone knows that everyone knows.

"The emperor has no clothes, but nobody says it until someone does."

Quick answer

What is Common Knowledge? Information that everyone knows, and everyone knows that everyone knows. Culture change requires making private knowledge common knowledge.

In the wild

A known problem is not fixed until a leader names it publicly.

Why it matters in the room

Culture change requires making private knowledge common knowledge.

Counter-move

Use all-hands forums to name the unnamed.

Visual · Pattern
Common Knowledge — a recurring shape in how people decide.
Live example · Apply Common Knowledge

Use the model. Pick the move.

Information that everyone knows, and everyone knows that everyone knows. You've just seen this: A known problem is not fixed until a leader names it publicly. Which lever does the model recommend?

● Live

Pick a lever. There are no neutral ones — every incentive funds a behavior somewhere.

How does this land?

Pick a reaction to Common Knowledge

One tap. We'll point you at the most useful next surface based on how this hits.

Human Behavior Element™ · HBE Spec

The full taxonomy entry

Every concept in the Atlas uses the same structure — so Common Knowledge can be compared, recombined, and cited like an element on a periodic table.

About the standard →
M
CK
HBT-M8844
Official name
Common Knowledge
Mental Models · Social
Identity
HBT ID
HBT-M8844
Symbol
CK
Official name
Common Knowledge
Synonyms
Social
Keywords
Mental Models, Social, human behavior, incentive design
Version
v1.0
Last updated
Maintained by The Incentives Lab
Classification
Kingdom
Cognition
Domain
Frameworks
Family
Mental Model
Class
Social
Element
Common Knowledge
Definition
Scientific
Information that everyone knows, and everyone knows that everyone knows.
Plain-English
Information that everyone knows, and everyone knows that everyone knows.
Feynman
The emperor has no clothes, but nobody says it until someone does.
Core principle
Information that everyone knows, and everyone knows that everyone knows.
One-sentence summary
Culture change requires making private knowledge common knowledge.
Mechanisms
Psychological
Information that everyone knows, and everyone knows that everyone knows.
Behavioral econ.
Culture change requires making private knowledge common knowledge.
Neurological
Reward, threat, and salience circuits bias attention toward the cue.
Evolutionary
Heuristics that paid off in ancestral environments now misfire in modern systems.
Sociological
Group norms and status incentives reinforce the pattern across a team.
Computational
Models trained on biased human signals will replicate and amplify the pattern.
Systems thinking
Feedback loops between metrics, incentives, and behavior lock the pattern in place.
Signals & signature
Inputs (activators)
A known problem is not fixed until a leader names it publicly.
Outputs (observable)
Culture change requires making private knowledge common knowledge.
Behavioral signature
You see Common Knowledge when the explanation for a decision sounds reasonable but the outcome keeps repeating.
Behavioral molecules
Often combines with related Atlas entries — see the rail below.
Pathways · before
A goal, metric, or contract clause makes the behavior rational locally.
Pathways · after
Locally rational choices accumulate into a systemic distortion.
Domains where it shows up
  • Business
  • Leadership
  • Government
  • Healthcare
  • Education
  • Sales
  • Marketing
  • AI
  • Negotiation
  • Media
  • Public Policy
  • Relationships
Examples
Everyday
A known problem is not fixed until a leader names it publicly.
Modern
Culture change requires making private knowledge common knowledge.
Historical
A pattern repeatedly documented since the foundational behavioral science literature on mental model.
Famous experiments
See the References block — primary papers in the Atlas link out to the original studies.
Design principles
How to leverage
Culture change requires making private knowledge common knowledge.
How to reduce
Use all-hands forums to name the unnamed.
How to redesign
Use all-hands forums to name the unnamed.
The Perverse Incentive Lens™
How it's exploited
Organizations weaponize common knowledge — sometimes deliberately, often by accident — when metrics reward the symptom rather than the outcome.
Common perverse incentives
Volume metrics, short review windows, bonus cliffs, and contracts that pay on activity rather than impact.
Failure modes
When Common Knowledge dominates, teams optimize for the dashboard while the real outcome quietly degrades.
Incentive redesign
Use all-hands forums to name the unnamed.
Ethical considerations
Don't engineer common knowledge into customers, employees, or citizens as a manipulation tactic — design for informed choice instead.
Diagnostic questions
  • Where in our org would Common Knowledge most often show up unnoticed?
  • Which metric, ritual, or contract clause quietly rewards Common Knowledge?
  • If we removed every payoff for Common Knowledge, what behavior would replace it?
  • Who benefits when Common Knowledge persists — and who pays the cost?
Organizational warning signs
Metrics
A KPI is hit while the underlying outcome stalls or worsens.
Behaviors
People route around the rule rather than challenge it.
Language
'That's just how we do it here.' / 'The system requires it.'
Culture
Naming the pattern is treated as disloyalty.
Red flags
  • People defend the status quo using the language of common knowledge.
  • Decisions cluster around the easiest narrative rather than the strongest evidence.
  • New data changes the slide deck but not the decision.
  • Anyone naming the pattern is treated as the problem.
Intervention playbook
Immediate
Make the perverse payoff visible to the people creating it.
30-day
Run a small pilot that pays for the outcome, not the proxy.
Long-term
Rewrite the comp plan, contract, or ritual so the right behavior becomes the easy behavior.
AI considerations
Detect
Audit training data and reward signals for the same pattern this element describes.
Avoid amplifying
Don't optimize models on metrics that already encode the perverse incentive.
Counteract
Use the model to surface where the pattern is most active, then redesign the incentive — not the model.
Measurement
Metrics
Outcome-to-proxy ratio over time.
Assessment
The Incentives Lab III Diagnostic.
Survey
Calibrated pulse questions on rules vs. outcomes.
Behavioral signals
Where people work around the system.
Observational
Where the dashboard and the lived experience disagree.
Scientific evidence
Evidence grade
Synthesized from the behavioral science literature; see Atlas references.
Replication
Tracked in the Atlas as primary, replicated, or contested.
Intervention confidence
Moderate — patterns generalize, mechanisms vary by context.
Research consensus
Broad agreement on the pattern; ongoing debate on boundary conditions.
Known limitations
Local context, culture, and incentive structure all change the strength of the effect.
Open questions
How does Common Knowledge interact with AI-mediated decisions at scale?
References
Meta-analyses
Tracked in the Atlas registry.
Seminal authors
Kahneman, Tversky, Thaler, Ariely, Cialdini, Ostrom, Simon — and the field they built.
Cross references

Every Atlas entry is a node in a knowledge graph. See the related rail below to follow the connections.

Disciplinary layers

See Common Knowledge through 2 lenses

Each layer of the Incentives OS reframes this concept with its own thinkers, vocabulary, and diagnostic question.

Test yourself · 60 seconds

Do you actually know Common Knowledge?

Three quick questions. Result is saved into your review streak — come back when the term is due to lock it in.

Question 1 of 3Score: 0/3

Which best describes Common Knowledge?

Go deeper

Worked example, counter-example & concept map

On-demand AI analysis grounded in the Lab's research. Cached on your device after first run.

How this lands in you

Your nervous system has a region for this.

Primary region
Default Mode Network

When you encounter Common Knowledge, your default mode network folds the experience into your ongoing story-of-self — which is why the same fact lands differently depending on who you think you are.

Self-referential thought, mind-wandering, narrative-of-self, mental time travel. Most of your waking thought is this network running scenarios about you, your status, your past, and your future.

See Default Mode in the Brain Atlas →
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More definitions to follow

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