One of the most useful ways to understand religion is to treat it as a way humans achieve social coordination. Steven Pinker’s recent work on common knowledge offers a sharp insight about this. “Common knowledge” is not merely that many people know something; it is the further (and crucial) fact that everyone knows that everyone knows it, and everyone knows that everyone knows that everyone knows it—an infinite regression that human beings handle with surprising ease in daily life.
This strange cognitive capacity is not just a philosophical speculation. It is a practical tool that makes civilization possible. In Pinker’s framing, common knowledge generates coordination: it lets people converge on shared conventions (driving on the right, accepting paper currency, showing up to the same meeting place at the same time) without needing a central enforcer to micromanage every choice. But the same logic also explains the “shadow side” of social life: why people avoid saying obvious things out loud, why hypocrisy can be stabilizing, why shaming mobs ignite, why revolutions seem to erupt “out of nowhere,” and why public rituals—of all kinds—have such force.
Religion is, among other things, a machine for manufacturing common knowledge. Private belief is psychologically real, but socially weak. It does not coordinate strangers. A society cannot run on invisible beliefs that no one can observe. What rituals do—prayer spoken aloud, communal singing, congregational responses, public confessions, initiation rites, sacred calendars, distinctive clothing, a crucifix necklace, shared dietary rules—is turn inner states into public signals. They convert “I believe” into “we all see that we believe,” and then into “we all know that we all see that we believe.”
This matters because people are extremely sensitive to the social risk of being the odd one out. If belonging is the reward and ostracism the punishment, the most dangerous condition is uncertainty: Do they believe this? Do they know I believe it? Do they know I’m wavering? Rituals collapse that uncertainty. They make allegiance visible. They create an emotionally saturated version of a contract—less like signing a document, more like standing under a spotlight and letting the group watch you sign with your whole body.
This is why religions place such emphasis on public acts. Private prayer is meaningful to many, but communal prayer is socially decisive. Singing alone is esthetic; singing together is social glue. An individual moral intuition is fragile; a moral intuition recited in unison becomes harder to question, because questioning it is no longer a solitary cognitive act—it is a social offense. And once a belief is entangled with common knowledge, its truthfulness often becomes secondary to its coordination-value. The belief may be fictional, but it is socially efficient.
Common knowledge is not only about shared content; it’s also about credible commitment. A cheap signal is easy to fake. A costly signal is harder to fake, which is why social groups are so attracted to cost. High-demand religions—those that require many hours of weekly participation, tithing, conspicuous behavioural restrictions, sexual policing, or public displays of devotion—often look irrational or excessive from the outside. But through the common-knowledge lens, some of this “irrationality” is exactly the point. If a group can get you to do something that is inconvenient, stigmatizing, or effortful, it has a way to distinguish true loyalists from casual tourists. The sacrifice itself becomes evidence.
This is also why initiation rituals recur across wildly different human groups, religious and otherwise. The ordeal is a signalling device: “I paid a price to be here; therefore I must value being here; therefore I am one of you.” The group sees the price, and the price creates common knowledge of commitment.
Pinker makes an additional point that is deeply relevant to religious life: people do not always want knowledge to become common knowledge. They often go to great lengths to ensure that even if everyone privately knows something, no one is forced to publicly acknowledge it. Many communities function because people collude, tacitly, in not pressing certain questions to the point of explicitness. The moment a doubt is spoken plainly, it stops being a private flicker and becomes a social event. It demands response. It forces alignment. It threatens the shared story.
I can't help but think there are many private doubts about very alarming world events that members of large partisan groups are having in parts of the world today, but few people within these communities have the willingness to speak their doubts out loud, since they would risk losing the support of their community. It reminds me of the fairy tale The Emperor's New Clothes--this story is especially apt to our modern times, since many of truths of the current world situation are so obvious that a very young child would be able to understand them clearly, and perhaps the innocence and humility of a child's voice is exactly what is needed to be convincing to those currently unwilling to speak the truth. Furthermore, one definition of heroism, in my opinion, is having the willingness to speak one's private knowledge of the truth to a group that might at least initially reject you for it.
In practice, a religious community often survives not by answering every question, but by managing which questions are ok to ask.
Religious spectacles—miracles, exorcisms, dramatic conversions, speaking in tongues, revival meetings—are not just theological events. They are high-powered signalling events. They take a private feeling (“I felt something”) and turn it into a public fact (“We all saw her fall, shake, cry, speak strangely, rise transformed”). The group witnesses a performance that is emotionally contagious, and the witnessing itself becomes part of the evidence.
The crucial move is not that an unusual event occurs, but that everyone sees everyone seeing it. This is how common knowledge is made at high speed: a shared spectacle that forces a shared interpretation, or at least a shared posture. If you stand in the room and do not respond, you are not merely unconvinced—you are socially deviant. The power of the event is partly the power of mutual surveillance.
This is also why sceptical outsiders often have a dual reaction to certain public charismatic performances: amusement at the apparent absurdity, mixed with unease at the real influence such spectacles can have when they become fused to political power. The performance may look ridiculous, but its social function is very serious: it converts theatrical intensity into tribal certainty.
A frequent defence of religion is that it provides moral structure. That claim is not wholly wrong—at least at the level of group coordination. A community that repeats moral language weekly, that teaches children shared scripts for gratitude, restraint, charity, and self-scrutiny, will often produce decently socialized people. The group is continuously manufacturing common knowledge about what counts as admirable, shameful, or forbidden.
But common knowledge cuts both ways. It can coordinate kindness; it can also coordinate cruelty. When a group makes contempt for outsiders common knowledge—through sermons, jokes, or political messaging—the moral atmosphere shifts. People become emboldened. What was privately felt becomes publicly permitted. The difference between a prejudice that quietly lingers in someone’s mind and a prejudice that is openly shared is enormous: the second is actionable. It becomes policy. It becomes bullying. It becomes violence with a clean conscience.
We see today a rise in bullying and prejudice in part because of this common-knowledge effect--various groups are coordinating a social norm by which prejudicial thinking is shared by a community, and becomes an emblem of partisan group involvement.
The frightening historical efficiency of religious persecution is, in part, a story about common knowledge: it is easier to harm others when the group has made the justification publicly shared, ritually repeated, and socially rewarded.
Common knowledge is not only created in sanctuaries; it spreads through networks. Here the work of Nicholas Christakis is a useful complement. His research argues that behaviours can “cascade” through social networks—spreading from person to person to person, sometimes out to several degrees of separation. Human behaviour is not merely individual choice; it is often contagious.
Religion has always understood this intuitively. Congregations are network structures: friendship graphs with rituals attached. Conversion is rarely solitary; it is more often a relational event. People move toward belief because a trusted person pulls them toward a group in which belief is common knowledge. Doubt spreads similarly: not primarily through reading an argument, but through watching someone you respect begin to treat the sacred story as optional. The moment that becomes visible, it becomes socially thinkable. It becomes “sayable.” It becomes a potential cascade.
This is one reason religious authorities, across centuries, have been so preoccupied with public dissent. Private doubt is manageable; public doubt threatens contagion.
The “New Atheist” era often tried to treat religion as if it were primarily a set of factual claims—claims that could be refuted, one by one, by geology, evolutionary biology, textual criticism, or cosmology. Those refutations matter. But they often fail to persuade for the same reason a spreadsheet rarely defeats a love affair: the object is not merely an idea; it is a social world.
If religion is partly a technology for manufacturing common knowledge—about belonging, virtue, status, and identity—then a purely evidential critique will bounce off the surface for many people. The deeper structure is social. To leave a religion is not only to change one’s beliefs; it is to risk becoming unintelligible to one’s own tribe. In the harshest cases, it is to risk exile. The mind treats that as a danger.
This also helps explain why political leaders so often perform religiosity even when their lives show little evidence of it. Performance creates common knowledge. A staged photo with a sacred symbol is not primarily addressed to God; it is addressed to the crowd. It signals, “I am one of us,” and it invites the crowd to become complicit in acting as if that were obviously true. Once the performance becomes common knowledge, dissenters inside the coalition pay a social price for pointing out the obvious.
Therefore, the secular task is not only to critique supernatural claims. It is to build non-supernatural forms of common knowledge that can do some of the same social work. Something like this is already happening in the modern world. People gather around causes, institutions, professions, civic rituals, scientific identities, mutual aid networks, even exercise cultures. These can be silly or beautiful; freeing or authoritarian. The point is not that secular life lacks ritual. It is that secular rituals are often fragmented, unstable, less grounded with deep roots going back into one's family tree and ethnic culture, and less explicitly oriented toward moral formation. The art and esthetics of the secular world is also far less-well developed than that of the religious world.
Religion persists not only because people are credulous or fearful, but because religion solves hard social problems. Pinker’s concept of common knowledge helps explain how it solves them—sometimes in ways that elevate human life, sometimes in ways that deform it. And once one sees religion as a social technology of visibility—of signals, rituals, and shared scripts—one can critique it more honestly: not as a childish mistake, but as an ingenious human invention that exacts a price.
The deeper question is whether we can build a life, and a society, in which the best human goods that religion has traditionally coordinated—community, moral aspiration, awe, mutual care—can become common knowledge without requiring that we pretend, together, that comforting fictions are facts.
