The Logic of Common Knowledge
Discover why shared information is not enough to drive action until everyone knows that everyone knows it. Learn to diagnose silent majorities, coordinate collective decisions, and leverage the power of public broadcasts.
Like Duolingo, but for The Logic of Common Knowledge. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.
A short one: 12 levels across 2 sections, about 24 minutes end to end, roughly 5 days at five minutes a day. It moves through Seeing What Everyone Knows and Engineering Mass Coordination. It assumes you already know the basics.
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Key ideas in The Logic of Common Knowledge
- Private knowledge lets people adjust solo habits without risk.
- Public coordination requires confidence that others will step forward simultaneously.
- Common knowledge eliminates the fear of individual exposure by confirming mutual awareness.
- Recursive knowledge chains collapse after just one or two mental iterations without shared cues.
- Infinite recursive depth requires an explicit, visible broadcast mechanism.
- Unstated mutual observation creates ambiguity about what the counterpart actually registered.
- Everyone in the crowd already saw the nakedness as private individual knowledge.
- Public announcements create simultaneous awareness that everyone witnessed the same event.
- Converting private consensus to common knowledge legitimizes public response.
- One-on-one reviews keep shared grievances siloed as isolated individual complaints.
- Disabling reply-all or forum threads permits mutual complaint while blocking shared visibility.
- Public spectacles generate common knowledge of enforcement rather than shared resistance.
- Why shared private beliefs fail to spark collective action until common knowledge is established
- Information deficits require private instructional distribution of facts.
- Coordination paralysis requires an open forum to prove everyone holds the same awareness.
- Pluralistic ignorance breaks only when private consensus is surfaced into open shared awareness.
You've tried the other tabs
Thirty open tabs. Four facts you actually kept.
You watched. You nodded. By Sunday it was gone.
One answer, then back to scrolling.
Eight weeks. You meant to finish. You didn't.
Tomo gives The Logic of Common Knowledge the Duolingo treatment: levels, streaks, and quick quizzes that test what you just learned. That game loop is what the tabs above never had, so it's the one you actually finish.
Here's what playing it feels like
A real question from this course. Take your best guess.
What must people trust before they are willing to join in collective public action?
Get it right to open this lesson and 11 more in the app.
Where The Logic of Common Knowledge takes you
- 1
Seeing What Everyone Knows
- Distinguishing Mutual and Common Knowledge
- Breaking Pluralistic Ignorance
- 2
Engineering Mass Coordination
- Public Broadcasts and the Arena Effect
- Thresholds and the Coordinated Attack Problem
2 sections · 4 units · 12 levels. Built to play, not to enroll.
You pick the voice
The Logic of Common Knowledge is taught in the The Professor style: clear, structured, thorough. Want a different feel? In the app you can spin up the same topic in any of Tomo's teaching styles. Same facts, totally different vibe.
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