Our febrile world is not normal.

The big picture: The precautions that we're taking against the spread of COVD-19; the way in which the president of the U.S. delights in violating political norms; the fires, hurricanes and other signs that catastrophic global warming has arrived; the virulent spread of the QAnon conspiracy theory — all of these things, and many more, represent a stunning break with the world as we knew it.

Why it matters: Society is made up of what Santa Fe Institute president David Krakauer calls "collective public ledgers." Many of those institutions have "tipping points" — the rate of surface change can seem slow, even as deeper underlying dynamics set the stage for a sharp or violent change in public opinion.

What they're saying: "You can think about bodies of belief like a huge public ledger," says Krakauer. Every individual inscribes their opinions into the ledger, and most of the time the ledger itself moves much more slowly than private opinions do.

• Depending on where you set certain initial assumptions, ledgers can be largely static, they can evolve slowly, they can flip back and forth in a predictably volatile manner — or they can flip suddenly, like a phase change from liquid to gas.

Between the lines: It's easy to think of public opinion about wearing masks, for instance, as a top-down function reflecting the differing messages sent by various public figures. That's easy to believe in the U.S., where attitudes to mask-wearing align strongly with political beliefs. But it has a harder time explaining why, say, only 58% of people in Italy regularly wear a mask, compared to 93% in Spain.

Krakauer has spent his career studying complexity, which is a defining feature of the pandemic — and of the whole world, at the moment.

• The virus is a great example of a stochastic disease, as Zeynep Tufekci explains in The Atlantic. "Randomness plays a much larger role," she writes, "and predictions are hard, if not impossible, to make."
• The QAnon conspiracy theory is similarly complex and unpredictable, morphing from its far-right roots to infect wellness influencers and left-wingers like Piers Corbyn, the brother of former U.K. Labour Party leader Jeremy Corbyn.

The bottom line: After the "black swan" and "25 standard deviation events" of the financial crisis, followed by the victories for Brexit and Trump in 2016, and now a global pandemic, society has started to expect the unexpected and embrace the irrational.

• People now rationally expect that unlikely fat-tail events will happen multiple times per year. That expectation in turn makes it much more likely that they will rewrite the ledger of societal institutions.