The Mathematics of Persuasion

By James Wallace Harris, Sunday, December 6, 2015

I’m fascinated by the idea of society changing. This week it was announced that women will have access to all combat roles in the U. S. military. It wasn’t many years ago that would have been unthinkable. It’s less than 100 years since women got the vote in the United States, and now we could be close to having a woman President. Or think about the cultural shift of same-sex marriages. I’m already seeing charming ads by wedding planners running photos that feature a man and a woman, woman and woman and man and man couples. There’s also a lot of movement to legalize marijuana in various states. Society seems to be changing fast. But in other ways, it doesn’t. Even though we have a black President race relations are still very troubled. Sometimes I think culture can change fast, but not necessarily individuals.

This makes me wonder about how an idea gets converts, and how fast a society can transform with a new idea. If one person takes up a new belief and convinces one other person, and they convince one other person, how long before it changes society? Of course, that depends on the frequency of conversion. But if one person converts two, and the two convert four, it would only take 30 doublings to covert all Americans to a new idea, or 34 for the world. See the classic rice on chessboard legend. If each doubling took a year, it would take three decades, but if it took a week, it would take less than a year.

Think about ideas that are emerging now. One that I’m interested in is the plant-based diet. My cholesterol numbers have gotten much better since I started that diet. I’ve lost weight, feel much better, and have much less inflammation. This convinced two of my friends to try it. Most people love to eat meat, but what if eating a plant-based diet turns out to be proven path to health? How long before half the country goes vegan? Most people will scoff at that idea as being downright silly. But it was only 150 years ago that this country had slavery, women couldn’t vote, cars didn’t exist, we didn’t have the income tax, and most folks died of things we consider curable today.

Things change. How long did it take abolitionists in the 19th century to enlighten enough people to change the country? How long will it take environmentalists to convince the world that climate change is something we need to stop?

I wish I knew the mathematics to answer this question: What is the difference between one person making one convert a year, or two converts a year, or three, four, five, or more? Social movements are built around people changing their minds and becoming converts. However, it’s also about old believers dying off. The growth of atheism and agnosticism is mainly due to older believers dying. That suggest that some changes takes a life-time.

I’m reading a tremendous book right now, Countdown by Alan Weisman, that is about overpopulation. Weisman reports from over twenty countries how different cultures view population growth, and their various approaches to sustaining ever growing populations with dwindling resources, in a world where the environment is collapsing. There is no question that we’re on a doomed path. The question is whether or not the mathematics of persuasion even has time to work.

I am writing a series of essays about how I’m looking for signs of hope for the future. So far, the only solution I can find is for seven billion people to change the way they live. Humans do change, but can they change fast enough to solve all the problems we face before we’re forced to live in a post-apocalyptic world? It’s no longer about surviving climate change, that’s just one of many of our problems, and I’m no longer sure it’s even our most threatening problem. Exponential growth, which the world economy depends on, is about to hit the wall. Probably before 2050, or even 2030.

Remember that old domino theory about communism? Well, communism wasn’t the problem, collapsing civilization is what we need to watch. Iraq, Syria, Afghanistan, are the early dominos. Americans pay very little attention to what’s going on in other countries, unless they host a war that concerns us. But look how a war in Syria is affecting Europe. Keep an eye on Pakistan. Start counting the countries that are collapsing, and why. What would happen if Mexico collapsed? Pay attention to all the countries that have extremely high unemployment.

We can solve our problems if we can master the mathematics of persuasion. Unfortunately, we have built economic growth on a different set of mathematics which doesn’t equate with the mathematics of a sustainable environment. It’s like the Standard Model and Gravitation, they don’t seem to be related, but should be. We need to build an economy based on using less, and sharing more. That can’t be communism, even the Chinese have learned that. But it can’t be capitalism either. Socialism only solves some of the problem capitalism fails to solve. We need a whole new model. Probably some kind of steady-state capitalism mixed with socialism and environmentalism. But to transform society will require changing how seven billion people live. Is that even possible? We have nothing yet, so convert number 1 is waiting. And even if we had an answer, how fast can we go from 1 to 7 billion?

JWH