How does ‘common knowledge’ shape our individual lives and our societies? Steven Pinker has some ideas
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Steven Pinker.<br>Gage Skidmore, via Wikimedia Commons, CC BY-SA
https://theconversation.com/how-does-common-knowledge-shape-our-individual-lives-and-our-societies-steven-pinker-has-some-ideas-264129
https://theconversation.com/how-does-common-knowledge-shape-our-individual-lives-and-our-societies-steven-pinker-has-some-ideas-264129
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I don’t know about you, but ever since I can remember – from my early teens – I have been bemused about the endless rituals we humans perform; and even more so about what can and can’t be said about these rituals, especially when the rituals involve obvious hypocrisies or are illogical.
Review: When Everyone Knows That Everyone Knows: Common Knowledge and the Science of Harmony, Hypocrisy and Outrage – Steven Pinker (Allen Lane)
Do you see what I just did with my opening paragraph?
Obviously, through a brief personal reflection, I tried to give you a general sense of what much of Steven Pinker’s book When Everyone Knows That Everyone Knows is about: namely, that we often perform perplexing rituals for the sake of harmony, and if we draw attention to the quizzical aspects of those rituals – if we make these aspects common knowledge – we can get into trouble.
But I also did something else. I started with the innocuous, “I don’t know about you…”
Now hold on tight. This gets complicated very fast. Just like Pinker’s book.
The thing is, I do believe that many people are bemused by the rituals we perform and the silences we must keep. But I wouldn’t say that this phenomenon is itself common knowledge.
More accurately, I wouldn’t say that I know that you know that this is common knowledge. And I also wouldn’t say that I know that you know that I know that this is common knowledge.
In drawing attention to this phenomenon, however, I am, like Pinker, helping to make this phenomenon, which involves common knowledge, common knowledge.
I’m not joking. Well, actually, I am joking. But the joke is accurate. Pinker’s book goes on like this for hundreds of pages. Reading it is a discombobulating but glorious experience. Section after section takes us down one, then another, then another layer of reflexivity.
In doing so, the book brings to light the endless ways that common knowledge – knowledge that everyone knows that everyone knows – affects our individual lives and society.
Indeed, having read Pinker’s book, my sense is that tussling with “common knowledge” is just about the most common thing we humans do – it’s up there with breathing and sleeping.
Though it isn’t exactly common knowledge that this is the case.
What is ‘common knowledge’?
Common knowledge is not exactly knowledge in the sense of established and widely accepted facts. Pinker is not talking about Einstein’s General Theory of Relativity or other well-established truths, like calculus or maybe even the law of supply and demand, though such truths do come into it.
Rather, common knowledge refers to beliefs that are commonly held, and that people know to be commonly held. Sometimes these beliefs are true, sometimes not.
The book begins with the classic example of Hans Christian Andersen’s story The Emperor’s New Clothes. Pinker writes:
When the little boy said the emperor was naked, he wasn’t telling anyone anything they didn’t already know. But he added to their knowledge nonetheless. By blurting out what every onlooker could see within earshot of the others, he ensured that they now knew that everyone else knew what they knew.
And so the illusion could no longer be sustained.
In this instance, the little boy’s speech was a threat to the status quo. It undermined the emperor’s prestige and revealed to everyone that, for the sake of something like harmony, they were upholding a ridiculous lie.
Steven Pinker interprets the Emperor’s New Clothes as a story about common knowledge. Illustration by Vilhelm Pedersen (1849).<br>Public domain, via Wikimedia Commons
This account of common knowledge is useful. But Pinker’s immense insight concerns the way humans use common knowledge to coordinate action and bring about win-win situations. (Pinker, the great liberal optimist of our time, is drawn to win-win situations.) Humans have done remarkable things, and much of what we have achieved has been through cooperation: we work together to achieve common goods, which include not just survival, but progress.
Given that each of us is a universe unto ourselves, a fundamental question is: how do we coordinate our cooperation?
Pinker’s answer: using common knowledge. As he puts it:
Life is filled with opportunities to coordinate with other people for mutual gain. We agree on a time and place to meet, bring complementary fare to a potluck dinner, divide responsibilities...