How Common Knowledge Influences Society

In the latest episode of StarTalk, cognitive scientist Steven Pinker joins Neil deGrasse Tyson to unravel the intricate web of common knowledge—a phenomenon that might just be the invisible glue holding our civilization together. But what exactly is common knowledge, and why should we care?

The Social Fabric of Common Knowledge

Imagine a world where everyone knows something, but not everyone knows that everyone else knows it. Confusing? That's the crux of common knowledge. Pinker, in his usual eloquent style, explains that common knowledge is more than just shared information—it's about understanding that others are also aware of that information, and they know that you know it too. This recursive awareness is what allows us to coordinate actions, maintain social contracts, and uphold societal norms.

One might say it's the bedrock of civilization itself. As Pinker highlights, "Civilization does depend on institutions like government and money. The only reason a piece of paper with Abraham Lincoln on it is valuable is because other people treat it as valuable." This social reality extends beyond currency to encompass power, language, and even our cultural rituals.

Navigating Social Complexities

Common knowledge doesn't just shape macro-level structures like economies or governments; it seeps into our everyday interactions. Pinker dives into the subtleties of "weasel words" and "plausible deniability," where language becomes a tool to navigate social complexities without tipping the balance of relationships. "Acceptable duplicity," as Pinker terms it, allows us to maintain harmony by leaving certain truths unspoken.

Take, for example, the innocuous phrase "Netflix and chill." It serves as a social cue laden with innuendo that both parties understand without making it explicit. This shared, yet unspoken, understanding allows individuals to maintain social bonds without overtly stating their intentions.

The Role of Emotions

Pinker also touches on the evolutionary purpose of emotions like blushing, laughter, and tears—our non-verbal ways of generating common knowledge. These emotional displays are universal signals that transcend language, as Charles Darwin noted in his work on facial expressions. Darwin's observations suggested that such expressions are shared across cultures, debunking scientific racism and highlighting our common ancestry.

When the Social Contract Breaks

The discussion takes a turn towards the consequences of violating common knowledge. Pinker and Tyson explore how breaking social norms can lead to societal upheavals, like financial crashes or political revolutions. The "Emperor’s New Clothes" effect is a prime example, where the illusion of consensus crumbles once someone dares to speak the unspoken truth.

Speculative bubbles, whether in financial markets or societal trends, often rely on a fragile common knowledge. When that shared belief is questioned, the bubble bursts. This raises an intriguing thought: could fostering more robust and transparent social norms be the key to a more cohesive society?

A Curious Conclusion

In a world where the unseen threads of common knowledge weave through every aspect of our lives, Pinker's insights challenge us to rethink how we perceive social interactions. As we navigate this complex landscape, the question remains: Can we leverage common knowledge to bridge divides and foster a more harmonious world?

That, perhaps, is the mystery and the potential of common knowledge—a topic that, much like a good conversation, leaves us with more questions than answers.

Nadia Marchetti