Subtitled: Common Knowledge and the Mysteries of Money, Power, and Everyday Life
(Scribner, 2025, xv + 364pp, including 64pp of notes, references, and index.)
This latest Pinker book, which follows ENLIGHTENMENT NOW and RATIONALITY, seems at first glance a bit more abstruse or academic without quite the verve of theme that distinguishes most of his books. Yet upon review it is, rather like Harari’s NEXUS, nevertheless full of fascinating revelations and insights that make it key to Pinker’s oeuvre. In fact, it shows that Pinker’s concerns about the human mind, human nature, the nature of rationality and so on, extend into sociology and the many ways humans interact. (Rather like the way Harari’s exploration of information extends into politics.) All of his books, with only an exception or two, are of a piece.
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Key Points
Ch1 explains ‘common knowledge’ as what people know that they are aware other people know too (as distinct from the common use of the phrase, as knowledge that most people are aware of individually). Common knowledge enables ‘coordination games’ between different people, to enable cooperation. These can rely on focal points, aka conventions, which match what Harari calls ‘fictions’. Examples of viral memes, why dictators suppress expressions of opinion that generate common knowledge. Such ‘common knowledge’ can include unverifiable beliefs, as in religion and politics. Social media can generate shaming mobs, the examples from literature.
Ch2 explains how common knowledge relates to common sense, in three particular ways: you can deduce facts about the world from what people don’t know; an infinite vortex of “I know that he knows that I know…” is unavoidable; and rational agents with the same understanding of the world must arrive at the same conclusion: they cannot ‘agree to disagree’. And explaining why people still do disagree.
Ch3 looks at examples from game theory and how common knowledge applies: the Prisoners’ Dilemma, the tragedy of the commons, two people deciding where to meet. How cultures settle on different focal points. Coordination games of Chicken, and Hawk-Dove, and the Madman strategy.
Ch 4 explores the limits of recursive thinking in “you know that I know that you know…” situations. We can’t go more than four layers deep, so we have ways of thinking in ‘chunks’ and mental scripts to reduce such complexity. These involve reflexive or self-referential statements, or self-evidence from public events. People learn to anticipate what others think, usually not correctly.
Ch 5 considers altruism, why some donors choose to remain anonymous, and the Effective Altruism movement. Then looks at four styles of social relationships (or coordination games) in human cultures: Communal sharing; Authority ranking; Equality matching; and Market Pricing. These reflect the tensions between intuitive human relationships and the formal institutions that underlie modernity. One recent result of these tensions is modern ‘cancel culture.’ Many social practices are efforts to generate or avoid the common knowledge that would allow people to coordinate their social games.
Ch 6 looks at emotions, both involuntary and conscious: laughing, crying, blushing, staring, glaring. The first three evolved to establish certain kinds of common knowledge. Author finds Koestler’s ideas unsatisfying, and appeals instead to an early work by Darwin, explaining the evolutionary utility of such traits.
Ch 7 concerns words and innuendo and euphemism, the latter as ways to provide plausible deniability. Direct speech generates common knowledge; indirect speech and expressions are intentionally to avoid establishing common knowledge, but to leave things vague or ambiguous.
Ch 8 addresses the “canceling instinct,” as ways to suppress common knowledge, even in academic situations. People cite moral principles or other rationales for why some things should not be known; author favors intellectual freedom.
Ch 9 addresses why some things should not be common knowledge, that some knowledge should be private. We have a propensity to overshare, e.g. on social media. Examples of problems with complete honesty. Social interactions depend on conventions, which are idealizations, and would be undermined by by ‘radical honesty.’ With final thoughts about the power of human recursive thought, and how it makes human progress limitless.
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Detailed Notes
Preface
The author, like everyone, constantly thinks about what other people think, and so on. Common knowledge. The idea goes back to his book The Stuff of Thought (which I’ve not read). Common knowledge explains various features of social organization. … all the way to academic cancel culture.
Like Words and Rules (which I’ve not read either) this book features results of author’s own research.
1, The Emperor, the Elephant, and the Matzo Ball: what common knowledge is, and why it matters, p1
It’s the difference between the private knowledge of everyone seeing that the emperor is naked, and everyone knowing that they all know it. Example cartoons where knowing is depicted as seeing. This book aims to bridge psychology and cognitive science. Main ideas, p5. “Common knowledge” in this book means something different from the ordinary English sense. Mutual knowledge; other terms 7t. The meanings of words are the most prominent kind of common knowledge in our lives.
Language is the basic tool of social activity. It enables reciprocal altruism, p9, as modeled by the Prisoners’ Dilemma. Various moral sentiments, 9b, evolved to implement the strategy of reciprocity. (Author has told this story in five books.) But along with cooperation is the problem of coordination. When coordination works, everyone wins. Consider the game Rendezvous; each of two people tries to guess where they will meet. They’re missing common knowledge. Failing direct speech, the next best thing is common salience, or a focal point. Some random reason why one or the other choice might come to mind. Such a focal point, or commonly known solutions, are called conventions. These match the ‘fictions’ in Harari’s three books, 12b, quote 13t. Author would put it differently: the world is built on conventions that allow us to coordinate and are self-reinforcing because they are common knowledge, 13.4. [[ this is a good point for those who might feel that Harari trivializes things. Or object to religions being called ‘stories’. ]] Common knowledge creates nonphysical realities. These issues of cooperation create their own complex situations… Four examples.
Consider viral memes on social media. One example was mathematical. From 2015. The Cheryl’s birthday problem.
The turning point with home computers came in 1984 with the Apple Macintosh. The GUI had been tried before, it just hadn’t taken hold. The famous Super Bowl ad by Ridley Scott may have done it. Everyone who saw it knew that many other people were seeing it. Other products did the same thing. Super Bowl ads became as popular as the game itself. In 2022 came Bitcoin. Details about currency and blockchains. It’s all about expectation. Depending on ‘greater fools.’ Eventually bubbles can pop, as happened when the value of Bitcoin sank of 75%. Etc. Sam Bankman-Fried. Larry David in his ad was right.
Then there’s why dictators suppress expressions of opinion. Demonstrations generate a kind of common knowledge. Gandhi. Other regimes came to the same fate. (Covered in Better Angels.) With communications methods accelerating them. China has gotten good at subverting such nonviolent resistance movements. Solzhenitsyn on lying, 36.3. Example of a 2013 tweet about AIDS that went viral. Ruining her life. Justine Sacco. The beginning of cancel culture. Example from 2022 by Jonathan Haidt. Targeting the Like, Share, and Retweet buttons. Author can take this explanation further. Such shared posts become common knowledge. This is the big difference with social v traditional media: people can *generate* common knowledge.
This can generate a social media shaming mob. (Comment about unverifiable beliefs, 31.4. 31.5. about religion and political affiliations.) Examples. Norms are reinforced by punishing flouters. Instead of spectacles in the public square, now we have social media. Everyone eventually needs to watch everyone else. But why do some of these ‘punishments’ seem extreme, even sadistic? To clearly signal which faction people align with. Intentions matter. (Interesting aside about how archaic system of justice ignored intentions.) Similarly consequences matter.
Several works of fiction depict punitive mobbing. Koestler’s Darkness at Noon; Miller’s The Crucible; Orwell; Shirley Jackson.
We’ve considered logic, economics, politics, and public morals. One more key idea: social relationships are coordination games. And this depends on common knowledge. Shifts in relationship involve renegotiating common knowledge; and thus the manners of human social life. But why isn’t common knowledge common knowledge? We speak of it as conceptual metaphor. E.g., argument is war; love is a journey. Common knowledge is a conspicuous sight or sound. Example from When Harry Met Sally. Other examples, p40.
2, Common Knowledge and Common Sense, p43
The logic of common knowledge is often an insult to common sense. This chapter discusses three such cases:
1, you can deduce facts about the world from what people don’t know;
2, people do really need to think in an infinite vortex of “I know that he knows that I know….”
3, rational agents with the same understanding of the world must arrive at the same conclusion: they cannot agree to disagree.
Consider the brainteaser in which “three logicians walk into a bar.” Explained 45t. Another problem (from Asimov, Gamow, and Gardner) about cheating wives, later updated to cheating husbands. And other versions. Author gives his own version, about psychologists with spinach in their teeth. Explanation. Variations.
There are fictional examples, e.g. a David Lodge novel, the mystery genre in general. Example of Poe. This general game of psyching-out others extends to logic puzzles, mystery stories, and jokes. Examples.
Example of James and Charlotte deciding which coffee shop to meet at; it’s always a dilemma. The Electronic Mail game. Example of two army divisions coordinating an attack. Or fighter pilots. There are loopholes in all these scenarios. Examples of distributed computing and joggers at crosswalks. Goodbyes.
Agreeing to disagree. This can’t work; equal priors lead to equal posteriors. The background is Bayes’s Rules (covered in earlier book). It’s more or less common sense, though sometimes human flout it. … there’s no splitting the difference, etc etc. Facts don’t care about your feelings, etc. Example of who will win a literary prize. How arguments should go, diagram p69. Yet in real life people disagree even when they exchange their best-informed opinions. Why?
In mathematics it often works like the idea, where two parties will talk each other into changing their opinions. But most people anticipate future values. Which should have already been taken into account. Don’t follow hot tips, etc; don’t try to outsmart the market. Others like will have already heard about those tips. An issue is the assumption of equal priors. And people can believe anything they want, as their priors. E.g., not believing that Trump didn’t win the election. Maybe different priors are due to different backgrounds, and so on. But: it’s not about you. Your background doesn’t affect what’s true or false about the world. So why *do* people disagree? Because they’re convinced they’re smarter than the other guy. People condemn self-serving decisions in *others*. And people deceive themselves. In refined debating forums the style is gladiatorial combat, unshakable confidence on either side. In contrast are the forecasters, or the rationality community, or Bayesians. P75. Recall Lakoff and Johnson’s conceptual metaphors. Try to imagine them differently. Rational argument should be more like a dance than a war.
3, Fun and Games, p77
This chapter considers more common situations where common knowledge is a regular feature of human social life. These are ‘games’ from game theory. First we consider the Prisoners’ Dilemma, which is different from coordination games. See diagram. These ‘games’ don’t have winners or losers, but they often have an ‘equilibrium’. The game demonstrates the virtues of being altruistic. The tragedy of the commons is similar. But many human predicaments are Prisoners’ Dilemmas. The James & Charlotte dilemma, of where to meet for coffee, has two equilibria. How to reach one or the other? Here’s where common knowledge is necessary. With cell phones? But words are cheap. People and animals can lie. And would lie given a conflict of interest. Conversation is possible because of the default maxim of honesty. Con artists are the exception. Why did language evolve? Perhaps simply because it cheaply generates the common knowledge that makes social coordination possible, 84m.
Recall Thomas Schelling’s idea of common salience, or a focal point. Focus on whatever pops into your mind. When culture settled on a focal point, it becomes a convention. E.g. seven days in the week. Different cultures settle on different things; thus the variation among cultures. Thus, there are not Prisoners’ Dilemmas behind every tree. An arbitrary focal point can break such a dilemma. But sometimes interests conflict. Consider the ‘battle of the sexes.’ See an opera or a ball game? Bargaining.
These ideas go back to the Enlightenment. Example from Rousseau. The Stag Hunt. Similar to actual hunts where everyone must cooperate. Examples in earlier chapters match these ideas.
One more coordination game is called Chicken. Recall the James Dean movie, and also Bertrand Russell about the cold war. Many international conflicts follow this pattern. 96m. A similar conflict prototype is the Hawk-Dove game. Acted out by any two birds. Natural selection favors winning, but even more strongly if favors not dying. Numerous wars throughout history. Possession is nine-tenths of the law. One strategy here is the madman strategy, of relinquishing control. Recall Dr. Strangelove. One solution is a world government. In practice we’ve had the Long Peace since World War II, due to the territorial integrity norm: international borders are grandfathered in. That didn’t stop Russia in Ukraine. Yet, no nation has gone out of existence through conquest in this period. Also, the use of mediators and arbitrators. The Pope; the International Court of Justice. Unwritten rules to settle disputes among rural ranchers, etc. Thus legal systems are not just coercive, but expressive. The laws become self-enforcing. That doesn’t mean we can defund the police.
Ch4, Reading the Mind of a Mind Reader, p105
Examples of layers of ‘you know I know that you know…’ etc. If common knowledge entails such recursive thinking, why are these examples so difficult to think about? There are three main theories.
One is that it’s recursive, but that leads to an infinite number of propositions, which could not fit into a finite skull. There are ways of reducing this. Second, a reflexive representation. And third, self-evidence or conspicuity. Which of these do people actually use? First, we know children realize ‘theories of mind’ fairly early. Studies have been done. Children start to get second-order thinking around seven or eight. An age that’s been called the Age of Reason. How many levels can people think? Examples p116. Four; people had trouble with five. But it’s not that simple of course. … This works via content-addressable memory, represented as a single neural circuit. Thus you can’t not think about a polar bear. People fuse a collection of ideas into a ‘chunk’. Like breaking a phone number into chunks. Some chunks have their own words: bluff, deceive, doubt, etc. Mental scripts like “affair” and “scandal” and “argument” help us automatically extend recursive situations…
Two other theories of how people represent common knowledge. One is a reflexive or self-referential statement… Another is self-evidence. Such as public events. Example of coral using the full moon as a focal point for spawning.
Studies author has done with grad and post-doctoral students. Working alone or in groups. Examples of how much each person knows. The results were more or less rational, with blind spots.
Other experiments… Leads to ‘expectation’, beliefs about other people’s beliefs. A beauty contest. Experiments about trying to guess the most common guesses. They choose differently than their own favorites. Economists worry about things like these. Richard Thaler. Jumps in prices of mutual funds. Meme stocks. Bubbles and crashes, etc. Bank runs. Examples. Toilet paper in 2020. Example of Family Feud, trying to guess what other people most often think. And the American primary system for presidential elections, how small unrepresentative states set ‘momentum’ for the rest of the nation. Biden dropping out. (These are all cases of recursive mentalizing.) One more case: Kitty Genovese in Queens. The facts of the actual story were much more modest than had been reported. Still, bystander apathy exists. Everyone assumes someone else will get involved. Experiments with students. More examples. Volunteer’s dilemmas.
Ch5, The Department of Social Relations, p153
Author recalls learning in sixth grade about the Ladder of Charity, due to Maimonides. A ladder with 8 rungs, p154-5. Other rabbis had similar ideas. Larry David brought the ideas to life in Curb Your Enthusiasm. Whether donors remain anonymous or not. Gates, Jobs. Author did research into this area. It’s all about altruism. Then why do some donors wish to remain anonymous? Something called partner choice. The receivers of donations can choose who to deal with. All of this relates to the Effective Altruism movement, EA. Author studied whether this ladder makes intuitive sense today. Mostly, but not entirely. … we’ll see how levels of mutual knowledge govern the coordination games that underpin our social relations, 166m.
Consider a number of social paradoxes, 166-7.
These involve detection of genuine traits like honesty and fairness with ‘virtue signaling’. Social relationships are long games. Go back to Rendezvous. Relationships, friendships, are matters of common knowledge. Examples and details.
Alan Fiske has a theory of social relationships based on universals and diversity in human cultures. Three or four kinds of social relationships, or coordination games. First is Communal sharing, or communality. Solidarity is physical closeness, kindship, being made of the same flesh. Having the same mind. Details, including ancestry and gods. Preposterous beliefs, 173b. Nonverbal except for rituals.
Next is Authority Ranking: hierarchies. Common focal points like Hawk-Dove. Those on top are typically bigger or higher or earlier. Signals of dominance, like loud motorcycles. Reputation. Face. Facework: see list 176m. Overlapping this is Leader-Follower, 178.
Fiske’s third model is Equality Matching, equity or fairness. Relationships to create fairness. The Divide the Dollar game. Which explains the evolution of fairness.
Naturally these models are mixed and matched differently in different cultures. Some models can be applied where they don’t belong, creating confusion. Examples 184b.
Fisk’s fourth model is Market Pricing. Not to be mixed with Communal Sharing. The economic sphere, or the ‘rational-legal’ system governed by formal rules. [[ Constitution of Knowledge? ]] Representatives, not strongmen. Universities too, where friction between two grounds of belief has led to today’s cancel culture (Ch8). The tension between intuitive human relationships and formal institutions underlies the discontent of modernity.
These relationships are not just between individuals, but between classes, races, religions, etc. Communal outrage is analogous to a public insult. A recurring plotline in human history. Examples, up to Gaza. These aren’t revenge so much as solutions to two coordination games. Hawk-dove, and stag hunt. Entire nations act as if they’re more concerned about face than pursuing any rational strategy. Examples. More about quest for standing and revenge, than struggle for resources. Today, we have all these nuclear weapons. They’re status symbols. Thus the nuclear taboo.
Many social practices are efforts to generate or avoid the common knowledge that would allow people to coordinate their social games.
Ch6, Laughing, Crying, Blushing, Staring, Glaring, p193
About the muscles in the human face, the emotions it can express, how they’re common all over the world, and are similar to those of our primate cousins. (Note that some emotions depend on head or body position.) Then there’s laughter. Which is very different among people. Tears, blushing, gazing. All but the last are involuntary, and they can be understood as ways to generate common knowledge.
The study of humor is rather humorless. Author tried to explain this in How the Mind Works. Laughter can challenge a dominance hierarchy, or it can reinforce a communality relationship. One researcher actually analyzed a thousand instances of laughter. It’s usually public. It’s contagious. It’s involuntary. Much laughter is not in response to anything humorous. Laughter can be hurtful. (Obama and Trump.) So we come to the function of laughter. Humans have the social models discussed earlier; laughter is a way to undermine them. Climbing off the hierarchy. Communal sharing rather than authority ranking. [[ This is why Trump et al have no sense of humor. ]] And laughter, such as teasing and self-deprecation, disarms the battle for hierarchical dominance. Further: humor can challenge any arbitrary convention. This covers other examples of humor. Realize that humor is focused on jokes; jokes are a technology to generate a jolt of humor. Examples from Arthur Koestler. The resolution to an incongruity.
Crying. The oppose of laughter perhaps. Expressing sadness, from loss, defeat, or humiliation. Helplessness. A signal of surrender and of neediness. Arising from infants’ need to attention. But it can also be a source of pleasure, thus ‘tearjerker’. Crying for joy. Love and compassion in others: being touched, and moved. Certain memories. Examples. How to make sense of these? Examples of memories that can trigger tears. P208. A tearjerker is a kind of controlled dose of harmful stimuli, like hot peppers and saunas. Koestler’s ideas are not satisfying. Author has different ideas.
Go back to Darwin’s forgotten masterpiece about emotions. Three principles: serviceable habitats. Antithesis; examples of animal behaviors. Humor savors an infirmity; weeping savors a virtue. The sources are opposites of each other. But why are these emotions conspicuously displayed? Perhaps to advertise our sensitivity to such situations.
Blushing, p211. Another involuntary physical response. A display of embarrassment or shame. Dark skinned people blush too. But guilt doesn’t trigger it. What’s the point of blushing? Darwin fought the idea that facial expressions meant anything at all. Blushing is a signal that the person knows they screwed up. It earns them forgiveness and trust. What about blushing at praise? It’s a kind of self-deprecation. There are layers of common knowledge here. Common knowledge about being an anonymous referee in peer review. Experiments.
Staring, p222. Eye contact is the ultimate common knowledge generator. Other animals make eye contact, but only humans have eyes that make the direction of sight obvious. A stare is usually a sign of malignant intent. Barrooms, fights. The other guy blinked. Casual eye contact in social interactions isn’t as direct as that. People can pretend not to see each other. Passing for white. Being in the closet. Being fat, but never speaking of it. Consider how Silicon Valley gadgets about devices using site bombed; the device would hide your eyes. Videoconferencing may not endure; people can’t make eye contact.
Glaring, p228. The angry expression makes our threats credible. Experiment to demonstrate this: the Ultimate Game. With appropriate glares.
Ch7, Weasel Words, p231
Recalls a scene in Schindler’s List in which a bribe of diamonds is made without overtly saying so. Other examples of innuendo, euphemism, etc: Getting out of a traffic ticket. Shame if something happened to it. Come in to look at my etchings. Asking to pass the salt; indirect speech. Trump, Zelensky, and Biden, leading to an impeachment. Why not speak plainly? Innuendos provide plausible deniability. But author has a refinement to offer. The plausible denial is the common knowledge of the intended meaning. Similar to an idea in The Stuff of Thought in 2007.
Start by imagining life without indirect speech. Incomplete information; the driver doesn’t know if the officer is honest or not. Strategic Speaker theory. Need to consider the officer’s point of view: matrix 241b. They did an experiment.
What about everyday life, without the need of a bribe? Example of getting into a fancy restaurant. Bribes work! One reason for indirect language is not to presume one of those social situational models that may not be appropriate. Like the relationship between the customer and the maître d. Analogous situation include threats, sexual come-ons. Example of latter from Seinfeld.
But: people use indirect speech even when there’s no need for it. Also, is it plausible that innuendo wouldn’t be misunderstood? Direct speech generates common knowledge. Intention is necessary. Indirect speech maintains tentative relationships. … This theory had to be tested, p253. Only blunt propositions were generators of common knowledge. Experiments with five and six layers. Innuendo depends on context. And can help people overhearing you from taking you seriously.
Still, indirect speech makes social life possible, but it has a dark side. They allow people to perpetrate atrocities – Orwell, Schindler’s List.
Ch8, The Canceling Instinct, p263
The urge to prevent ideas from becoming common knowledge, even in the knowledge profession.
A list of provocative questions. Academic freedom came into the spotlight in 2023 with congress grilling universities about antisemitism. All part of the sinking reputation of higher education. Author co-founded the Council on Academic Freedom at Harvard in 2023. The subject emerges from two features of our psychology. Still, can’t consensus be doubted? Example of Covid, and how scientific cautions led to distrust.
Free speech is not absolute; there are plenty of exceptions. Universities have additional controls to fulfill their mission. But incidents of censorship on campuses recently don’t fit those exceptions. Some deliberately provoke. There’s always been repression of speech in various ways.
Why do people cancel? The ostensible motivation is moral. Defending the marginalized, etc. defending moral principles, even when their arguments were non sequiturs. Examples. This is moral philosophy 101 about fact vs value. And people arguing to win, not to be consistent. The trolley problem. Etc. This goes to the paradox of how a clever species like ours is so subject to nonsense (discussed in Rationality), 272m, and author’s explanation. Academics defend contradictory things; they’re only human. There’s still a streak of post-modernism about truth and facts.
Recall the lady who hoped Darwin’s theory wasn’t true, but if so, that it not become well known. This is resistance against common knowledge. Academics still do this. They’re afraid that some ideas might become common knowledge. When a prejudice becomes common knowledge everyone will feel free to act on it. 275. Speech police shouldn’t care if everyone knows something privately, only when they know everyone else knows it. Then people will defy those beliefs, leading to pluralistic ignorance.
So what’s a case for limiting intellectual expression? Perhaps a policy of “don’t go there” because some knowledge would upset civility, e.g. the idea of racial differences in intelligence. [[ ‘There are some things man was not meant to know.’ ]] [[ Or, know them only in private. ]] Chomsky made the point about racial intelligence, considering the significance of whatever the finding would be, would be slight. There are other such subjects too. Journalists muzzle themselves in some circumstances. Yes there are problems, and yes it may be too late. The default as always must be intellectual freedom. …It’s better to know what’s so, or what’s false. Various things are wrong, 280b, because they’re inconsistent with various moral commitments. Still, there’s a tension…
Ch9, Radical Honesty, Rational Hypocrisy, p283
Why not everything should be common knowledge.
Summary of methods of communicating common knowledge, not just speech; nonverbal, ritual and symbols, institutions. Social change is driven by the creation of new common knowledge. In some circumstances they avoid acknowledging common knowledge. Even formal institutions do so.
So why do we keep so much knowledge private? It’s been the historical trend. Scientists and historians have no compunction about disenchanting the world, or undermining hero myths. We have freedom of information acts. We overshare on social media. How much can we continue to bring things out into the open? Some things must be private by design.
But nobody really wants complete honesty. Recall the Jimmy Carter interview. Hillary Clinton later. Hot mics. Alexander Hamilton. Totalitarian states tolerate no privacy. We all have many things to hide. Thus Gen Z and old social media posts. Example of what being rude means. Tootsie. Science fiction writers can use various devices to reveal what people are thinking (examples in footnote). And in reality there’s a movement called Radical Honesty. Which can become creepiness. Ray Dalio and radical transparency.
Radical honesty is the greatest hypocrisy of all. We’re naturally sensitive and inhibited – but why? The logic of coordination and common knowledge provides the answer. Humans are massively interdependent, due to both altruistic cooperation, and mutualistic coordination. Social relationships are held together by conventions, which are idealizations, verging on fictions. Knowledge that would undermine those conventions is kept private. Examples of communal sharing, authority ranking, equality matching. Our imaginations run wild but in reality we are constrained by the world. Hobbes noticed this, and others. We realize other people have similar fantasies.
So understanding this can stop us from ruining our lives, or others. Police can’t enforce the letter of every law. Politicians have to balance knowledge of experts with the will of the people. Avoid speaking too clearly about arithmetic. Some policies rely on ‘deliberate ambiguity’. Higher-order rationalities.
Author summarizes how all of his books are about how cognition feeds its own outputs back into more cognition. Language, how human intelligence extends to reason about the universe, how human progress is possible, how rationality itself is limitless. We have thoughts about our thoughts, and this is how we’ve derived science, philosophy, and math, and has made human progress possible, and suggests that progress is limitless.
[[ this last section is all about the wisdom of applying or not applying the understanding of the previous chapters. ]]
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