Narrator: Imagine it’s the 1920s. You’re a marketing executive at the Lambert Pharmaceutical Company, and your product, Listerine, is a surgical antiseptic that nobody wants to buy for personal use. How do you create a market from scratch? You don't just advertise the product; you advertise the problem. You take an obscure medical term, "halitosis," and launch a massive campaign depicting the devastating social consequences of bad breath. Suddenly, people aren't just worried they might have bad breath; they're worried that other people think they have bad breath. Sales skyrocket, and a daily ritual is born. This wasn't just clever marketing; it was the creation of a shared social reality.

This fascinating intersection of psychology, marketing, and social behavior is the central territory of Michael Suk-Young Chwe's book, Rational Ritual: Culture, Coordination, and Common Knowledge. Chwe argues that to understand why we buy certain products, support political leaders, or join revolutions, we must first understand the powerful and often invisible force of "common knowledge"—the state of knowing what everyone else knows.

Narrator: At its core, society is filled with what are known as coordination problems. These are situations where an individual's desire to participate in an action depends on others participating as well. Consider a simple protest. You might be willing to join if you know thousands of others will be there, but you’d likely stay home if you thought you'd be the only one. The problem is, how do you know what everyone else is going to do?

Chwe explains that simple communication isn't enough. If a friend tells you they're going, that's one thing. But what you really need is the assurance that everyone knows that everyone else knows about the protest. This layered awareness—I know that you know that she knows that we all know—is what Chwe defines as "common knowledge." It’s the critical ingredient that allows large groups of rational individuals to overcome uncertainty and coordinate their actions.

Without this shared awareness, action fails. People hesitate, assuming others will do the same, leading to a self-fulfilling prophecy of inaction. Therefore, to understand how societies achieve massive feats of coordination, from adopting new technologies to overthrowing governments, one must first look for the social mechanisms that are capable of generating this powerful, shared state of mind.

Narrator: If common knowledge is the fuel for coordination, then public rituals are the engines that produce it. Chwe argues that we often misunderstand rituals—from coronations and religious ceremonies to modern media events—as being solely about their symbolic content or message. While the message is important, the true power of a ritual lies in its publicity.

A ritual’s function is not just to transmit information from a central source to each individual, but to let every individual know that all other individuals are receiving the same information at the same time. It’s the shared experience of witnessing that creates common knowledge.

A powerful historical example is the French Revolution. To break from the old regime, revolutionaries needed to establish a new, unified social order. Part of this involved replacing the chaotic patchwork of regional weights and measures with a single, rational system: the metric system. This wasn't just a technical challenge; it was a coordination problem. For the new system to work, everyone had to adopt it simultaneously. The solution was not just to pass a law, but to promote the metric system through grand public festivals and ceremonies. These events ensured that everyone saw the new standard, understood its importance, and, crucially, knew that all their neighbors were seeing and understanding it too. The ritual made the new reality common knowledge, paving the way for its successful adoption.

Narrator: This framework provides a new lens for viewing power. According to Chwe, authority itself is a coordination problem. A leader has power because their followers believe that other followers will obey. Public rituals are therefore essential tools for rulers to maintain their grip. Ceremonies like royal progresses, where a monarch would tour their kingdom, were not just for show. As Queen Elizabeth Tudor traveled through sixteenth-century England, the elaborate public displays reinforced her legitimacy. Each town that witnessed her procession knew that other towns had also witnessed it, creating common knowledge of her widespread support and divine right to rule.

This dynamic also explains how power is challenged. Revolutionary movements succeed when they disrupt the old rituals and create new ones. Lynn Hunt's work on the French Revolution shows that new political authority requires new symbols. The revolutionaries didn't just fight on the battlefield; they fought on a cultural one, replacing old symbols with new ones like liberty trees and public oath-taking ceremonies. These new rituals created common knowledge of a new, shared ideology, mobilizing the public and legitimizing the new order.

Even the design of physical spaces can be understood through this lens. The inward-facing circle, seen in structures from prehistoric kivas to modern city halls, is a perfect architecture for generating common knowledge. It allows every person to see every other person, confirming that attention is shared. Conversely, Jeremy Bentham's Panopticon prison design works on the opposite principle. By isolating prisoners and preventing them from seeing each other, it systematically destroys the possibility of common knowledge, making coordinated rebellion nearly impossible.

Narrator: The logic of rational rituals extends directly into our modern commercial world. Chwe points to Super Bowl advertising as the ultimate common knowledge generator in the United States. Advertisers pay millions for a 30-second spot not just to reach a massive audience, but because the audience is aware of its own massiveness.

This is especially valuable for "coordination goods"—products whose value increases the more people use them. Think of a movie. You want to see it so you can talk about it with your friends. Or a brand of beer, which signals you're part of a particular social group. Advertisers of these goods aren't just selling a product; they're selling participation in a social phenomenon. The Super Bowl ad creates common knowledge that "everyone" is talking about this movie or drinking this beer, making you more likely to join in.

Research confirms this. Data shows that advertisers of these "social goods" disproportionately buy airtime on the most popular shows and are willing to pay a higher price per viewer to do so. They are paying a premium not just for eyeballs, but for the common knowledge that those eyeballs generate. This explains why a niche show with a dedicated audience is less valuable for a brand like Budweiser than a blockbuster event, even if the cost-per-viewer is higher. The goal is not just to be seen, but to be seen being seen.

Narrator: The single most important takeaway from Rational Ritual is its powerful challenge to the traditional divide between culture and rationality. We often dismiss rituals, ceremonies, and cultural traditions as irrational artifacts of the past. Chwe masterfully demonstrates that these practices are, in fact, highly rational solutions to one of the most fundamental problems of human society: how to get people to act together. The content of a ritual matters, but its publicity—its ability to create a state where we all know that we all know—is its true, world-shaping power.

The book leaves us with a new way to interpret the world. The next time you see a political rally, a viral internet challenge, or a blockbuster movie premiere, look beyond the surface-level message. Ask yourself: What shared reality is being constructed here? Who benefits from this common knowledge? And how is this "rational ritual" shaping not just what you think, but what you assume everyone else is thinking too?