# When Everyone Knows That Everyone Knows . . .  Author:: Last accessed on  ## AI-Generated Summary None ## Highlights > I had long wondered why people often don’t say what they mean in so many words but veil their intentions in innuendo and doublespeak, counting on their listeners to read between the lines. The answer, I suggested, was that barefaced statements generate common knowledge but genteel euphemisms do not, and common knowledge is what ratifies or annuls social relationships. ([Location 39](https://readwise.io/to_kindle?action=open&asin=B0DV6FDFT6&location=39)) > First, common knowledge (in the technical sense) is logically different from private knowledge: learning about something in public, even if everyone already knows it, can change everything. Second, the main thing that common knowledge changes is the ability to coordinate: two or more people with common knowledge can benefit each other with complementary choices that they would have no confidence making with private knowledge. Third, because common knowledge is so potent, humans are intuitively sensitive to it, almost as if we had a sense organ for this logical concept. Fourth, this awareness is what has empowered our species to coordinate our behavior in social networks like communities, economies, and nations. For this reason, many peculiarities of public life—its mindless rituals, conventions, and norms—become intelligible as solutions to coordination problems. So do some of the pathologies of public life, including fads, mobs, panics, bubbles, and spirals of silence. Fifth, personal relationships—our bonds with family, friends, lovers, authorities, subordinates, neighbors, colleagues, and transactional partners—are also coordination games, and they, too, must be cemented by common knowledge. Sixth, because all of these coordination equilibria come with perquisites and obligations, we often find ways to work around them by preventing ourselves from knowing what everyone knows, giving rise to rituals of benign hypocrisy, pretending not to know, catching someone’s drift, and not going there. In other words, many of our tensions, personal and political, arise from the desire to propagate or suppress common knowledge. ([Location 112](https://readwise.io/to_kindle?action=open&asin=B0DV6FDFT6&location=112)) > The purpose of language is to coordinate our behavior—you pass me the pepper when I want pepper and the salt when I want salt. Language allows us to do this because it is a convention, a tacit agreement among the members of a language community to use words to refer to certain concepts, ([Location 142](https://readwise.io/to_kindle?action=open&asin=B0DV6FDFT6&location=142)) > Words are the earliest and most omnipresent exercise of common knowledge in our lives. ([Location 161](https://readwise.io/to_kindle?action=open&asin=B0DV6FDFT6&location=161)) > When a viral post is listed in a “What’s happening” or “Trending” or “Explore” column, it could become as commonly known as a Super Bowl ad, especially now that the mainstream media themselves often reproduce viral social media posts. This is the reason why challengers to the big social media platforms that claim some political or technological advantage, like Truth Social, Mastodon, and Threads, have made only minor inroads. They cannot claim to be a “town square” where the users know they will see what everyone else is seeing, and will be seen by everyone else. ([Location 488](https://readwise.io/to_kindle?action=open&asin=B0DV6FDFT6&location=488)) > The psychologists Peter DeScioli and Robert Kurzban argue that moral condemnation is not just a strategy to signal one’s virtue but a strategy for aligning oneself with a dominant faction. ([Location 533](https://readwise.io/to_kindle?action=open&asin=B0DV6FDFT6&location=533)) > As with all the norms that enable coordination, a social relationship is ratified by common knowledge. You and I are friends (or lovers, or supervisor and employee, or seller and customer) only if we both know that we are, and if we both know that the other knows, ad infinitum. The common knowledge between us may be generated by any of a variety of public signals: a ritual, like a wedding; direct speech, like “I love you”; a legal arrangement, as in a signed contract; or any of the countless symbols that competent members of a culture know how to interpret. ([Location 595](https://readwise.io/to_kindle?action=open&asin=B0DV6FDFT6&location=595))