Today humanity is reaching new heights of scientific understanding – and appears to be losing its mind. How can a species that doubled its lifespan, sequenced its genome, and developed vaccines for Covid-19 in less than a year produce so much fake news, quack cures, conspiracy theories, and “post-truth” rhetoric?
Steven Pinker is an experimental psychologist who conducts research in cognition, language, and social relations. He is the Johnstone Professor of Psychology at Harvard and has won many prizes for his research, his teaching, and his books, including The Language Instinct, How the Mind Works, The Blank Slate, The Better Angels of Our Nature, The Sense of Style, and Enlightenment Now. He is an elected member of the National Academy of Sciences, a two-time Pulitzer Prize finalist, a Humanist of the Year, a recipient of nine honorary doctorates, and one of Foreign Policy’s “World’s Top 100 Public Intellectuals” and Time’s “100 Most Influential People in the World Today.” In his latest book, Rationality: What It Is, Why It Seems Scarce, Why It Matters (Viking, 2021), Steven gives us a primer in logical thinking and an entertaining expedition through all the trapdoors we can tumble through when we try to parse reality or bend it to our will.
In this interview, I speak to Professor Steven Pinker about rationality. We discuss how he rejects the cynical cliché that humans are simply irrational cavemen out of time saddled with biases, fallacies, and illusions (after all, we discovered the laws of nature, and set out the benchmarks for rationality itself). We discuss how we (as a species) think in ways that are sensible in the low-tech contexts in which we spend most of our lives but fail to take advantage of the powerful tools of reasoning we’ve discovered over the millennia: logic, critical thinking, probability, correlation and causation, and optimal ways to update beliefs and commit to choices individually and with others. Steven also takes time to discuss how the rational pursuit of self-interest, sectarian solidarity, and uplifting mythology can add up to crippling irrationality in a society.
Collective rationality depends on norms that are explicitly designed to promote objectivity and truth. Rationality matters. It leads to better choices in our lives and in the public sphere and is the ultimate driver of social justice and moral progress.
Q: What is truth as it relates to human society?
[Steven Pinker]: Truth is an aspiration which none of us can ever know that we have attained. We commit that the truth is ‘out there’ and there are of course philosophical discussions on what we mean by truth – the most infuriating of which is that if x is true, it means y. We say something with the presumption that what we just said is true unless we indicate otherwise. Now… the question is this. How do we ever know when things are true or false? The answer is none of us ever can – but we can certainly try. Moreover, we know we can’t do it on our own. Nobody has a pipeline to the truth; nobody is imbued with divine revelation. We seek truth through institutions like science, journalism, governance, justice systems and record keeping. These are the bodies that make us collectively more suited to attain the truth. The assertion that any of us as individuals could find truth is laden with all our biases.
Q: Why is it so important we understand rationality?
[Steven Pinker]: Rationality applies whether you believe in it or not. One idea follows from another – or it doesn’t – and if you want some of your beliefs to lead to other beliefs, you have no choice but to be rational. Even what you and I are doing right here- asking questions about rationality- presupposes rationality! We are not persuading each other or our audience. We are not bribing them to mouth slogans or conclusions. We’re not threatening them if they don’t ascribe to our beliefs. We’re actively opening-up the conversation. It’s not too late to discuss why rationality is valid. We’re committed to it by the very act of discussing, arguing, debating, persuading and convincing.
Q: What are the dangers of irrationality?
[Steven Pinker]: Irrationality creates dangers at every level. The laws of cause and effect which govern our universe don’t care about our beliefs – so we’d better find out what those laws are and try and align our beliefs to them to eliminate guesswork. The consequences if we don’t? we’ll get sick, we’ll starve, our machines will break down.
We have certain values like killing is bad, life is good, health is good, education is good… we want to attain these values… and yet we have irrational beliefs that cause society to go-off in truly malevolent toxic directions such as Nazi Germany where a set of irrational beliefs and pernicious values led to the deaths of tens of millions.
Q: To what extent do we need story and mythology, and how can we have more healthy relationships with those worlds?
[Steven Pinker]: What if we couldn’t distinguish fact from fiction? There are stories we know pertain to things that never happened, and that’s fine for entertainment but we really are better off if the stories we use to justify our policies are true. The instinct to believe (or at least, not to care) whether a belief is fact or fiction is the source of a lot of the irrationality that people are seeing today such as the belief in crazy conspiracy theories. If someone asserts Hillary Clinton ran a ring of paedophiles from the basement of a Washington pizzeria, you’d say how could they actually believe that’s true? And if they do know it’s true… why are they not calling the police?! Someone actually broke-into that pizzeria with guns blazing – he was acting as if he really did believe that kids were being raped in the basement. For the vast number of other people who assert that belief, it’s not clear how much they believe it vs how much they’re just saying, ‘Hillary Clinton, Boo! I wouldn’t trust her not to do it…’
May of us (well, I hope many of us) think that you should only believe things that are true, not just things that rally your coalition, sect, or tribe. That belief is by no means universal, but it is a gift of the enlightenment.
There are beliefs we hold in some circumstances where it’s just beside the point whether they’re true or false. Some of these are conspiracy theories, some are religious beliefs. If a Christian really believed that your soul was going to be tormented in hell for all eternity unless you accept Jesus Christ as your saviour, the rational thing to do would be to torture Jews until they convert – you’d be doing them a great favour… you would be doing a favour to society if you executed them for spreading heresy to other people as it would prevent billions of people from being condemned to eternal torture in hell. Fortunately, most Christians today say they believe it, but don’t believe it in the way their medieval ancestors did – thank goodness. Religious beliefs are kind of like that… you affirm them… you assert them… you act on them as if they’re true in the same way that you may believe there is milk in the fridge (or not!).
Historical fiction is another example. Many people watch The Crown and treat it as if it was wholly true even though a lot of those scenes are wholly fabricated. It doesn’t bother the viewer – they enjoy the dramatization irrespective of whether it’s true or not. We’re all capable of enjoying things that are neither true or false, but which are uplifting and entertaining. A lot of people have made political assertions from that very same instinct, and if left unchecked, this can lead to disaster.
Q: Why does rationality seem so scarce in our world?
[Steven Pinker]: We have a growing inequality of rationality. At the top, we’ve never been so rational – we’ve accomplished technological miracles… we sequenced the COVID-19 genome in days and deployed vaccines in under a year… we’re travelling to space. Domains that used to be the subject of hunches, intuition and authority are now being subjected to evidence-based evaluation. We have evidence-based medicine, evidence-based policing, forum psychotherapy and fact checking in journalism. At the same time, we have pizzagate, QAnon, chemtrails and 9/11 truthers.
We’ve always been susceptible to conspiracy theories. Some of them pernicious like the protocols of the elders of Zion (a Tsarist antisemitic forgery purporting to describe a Jewish plan to control the world’s economy) and many of the deadly ethnic riots and conflicts we see today which are fuelled by evidence-free conspiracy theories.
We talk about the stories of miracles and scripture – what are they if not fake news about paranormal events. Right up to the beginning of the 20th century, when journalism really got its act together and adopted ethics codes, a lot of great journalists traded in outright fabrications – in colonies on the moon, sea monsters in the great lakes and miracle cures. They just didn’t care… if it was entertaining, who cared if it wasn’t true?
Let’s not forget the various quack cures that humans have practiced (including medical professionals) such as purging and bleeding for humoral deficiencies in the middle ages which was based on the belief that if you’re sick, you must have infected the body, and to be cured you had to push the infection out through sweat, blood, vomit and diarrhoea. Sadly, many of these pseudo-medical practices are still practiced today all over the world.
Q: How can we develop the tools to be more rational?
[Steven Pinker]: The social sciences give us tools to make sense of the world. They allow us to understand the trade-off between misses and false alarms, inherent to any signal detection task. If you have a signal from a room, you don’t know whether there’s something out there or whether it’s just noise. You have to make a decision that optimises the costs and benefits of either jumping the gun and seeing something that isn’t there versus missing something that is there.. You have to set the threshold and can reduce errors of both kinds if you can distinguish signal from noise. You get better forensics, better measuring instruments, a fairer judicial system….
Another example is Bayesian reasoning which is a mathematical formula, several hundred years old, that has only three terms (all of which are intuitive). Bayesian reasoning isn’t always intuitive but is essential to things like interpreting a mental test result. No test is perfect- there are false positives and false negatives. If you take a medical test with a certain number of false positives, and you get a positive result, there’s a chance you may not have the disease.
Q: Does this also extend to breaking-apart correlation and causation?
[Steven Pinker]: You might think that coffee gives you heart attacks, but it may actually be that the coffee drinkers you surveyed exercised less and that is what gave them heart attacks. We need to develop tools to disentangle correlation with causation. There isn’t the money in the world to conduct randomised controlled trials for every issue of causation that we’re curious about, but it’s always good to keep in mind that correlation may not indicate causal results.
Sometimes you may not be able to prove causation, but at least you should know they’re not the same thing and be wary of possible compounds.
Q: How should we better understand the rationality of risk and reward?
[Steven Pinker]: Risk and reward have almost become a cliché. You log on to a share dealing platform, and the first thing you see is risk and reward. This isn’t just about finance; however, this is about life. There is a theory that by many criteria is rational; namely that multiply the probability by the reward and cost, and you choose the option that has the highest- as they say- expected utility (where expected means most probable, and utility means good stuff that’s important to you). This model has been attacked by many economists for its limitations. A lot of Nobel Prizes have gone to people who’ve shown limitations in expected utility theory. Economists also point out a number of consumer irrationalities that appear to go against this formula like buying extended warranties on appliances- you’re taking out life insurance for your toaster! If you actually think about what it costs to replace your toaster and multiply it by the percentage of toasters that actually break, it’s clear that it’s a waste of money, but we’re seduced by it every time we buy a product.
More consequentially, look at the medical context. Utility isn’t just a mathematical scale when it comes down to our own values. Death is not just something that really, really sucks, it’s game over and people can be forgiven for treating death not just as a very bad scale where getting your favourite ice-cream is the ultimate good and dying is the ultimate bad.
On the other hand, as a society, every time we spend money on one policy it means that we have less money to spend on another. There are lots of policies that affect people’s lives – public health, safety, policing, infrastructure and whilst it may feel repugnant to do so – many of these policies come down to the question of how much money we are willing to spend to save a life. The number can’t be infinite otherwise we would spend all our money on pedestrian overpasses and have nothing left. It’s a grim calculation that we must make if we don’t want to do crazy things individually or as a society.
Q: How can (or should) we disconnect our emotional from our rational minds?
[Steve Pinker]: Perhaps the most profound misunderstanding when it comes to rationality is the notion that to be rational, we must be unfeeling robots, like Mr. Spock on the original Star Trek or that we mustn’t hug our children because… well.. what’s the rational argument for that? David Hume argued over 300 years ago that rationality is always a means to an end, though nobody can tell what the end will be.
The fact that I prefer pleasure to pain… There’s no logical argument for that, I just do… that’s okay. Once we’ve decided on our goals (what gives us pleasure or satisfaction) it’s rationality that helps us attain those goals. That said, it doesn’t mean you should never put your own values to rational scrutiny. You could talk- for example- of the trade-off between what gives you pleasure and what gives everyone else pleasure. That’s the essence of morality. You can think about different goals you, yourself might have like physical pleasure now versus healthy relationships and esteem over the long term.
Q: How can game theory help us be more rational?
[Steven Pinker]: Thinking in game theory is an essential cognitive tool to being a rational, educated person. People think of game theory in terms of Dr. Strangelove and amoral nerds plotting mutual destruction. It is- however- a way of anticipating the effects of your decision in the context of other people’s decisions and can lead to some very non-intuitive outcomes that are essential in planning our own lives and in developing policies as a society. Think about climate change… can you call on individual conservation as a means of saving the planet? Can you tell everyone that it’s in their own interests not to overheat the planet and so they should fly less, buy electric cars and turn down the thermostat? Yes, it sounds rational… but… as a society we may be better off while the individual is worse off, sweating on a hot day without their air conditioning or waiting at a rainy bus stop while someone glides past in their gas guzzling car. It would be quite rational for the individual to say that no matter how much they conserve, the planet will still heat-up. If everyone’s thinking that, no-one’s going to do it, everyone’s worse off. That’s an example of game theoretic thinking, sometimes called the tragedy of the commons or negative externalities or the public goods game.
You have to change incentives for everyone. You have to change individual costs and benefits in a way that clearly makes the better decision more rational. One method could be a carbon tax – which creates a clear economic incentive towards less carbon intensive or harmful activities.
Q: How can we start to apply the tools for rationality in our lives?
[Steven Pinker]: I do think everyone would benefit from mastering the tools of rationality. These are tools that should be taught at school, they’re the basis for thinking about everything else from history to economics and from geography to literature in the same way that writing opens worlds to us.
When you and I fret over public irrationality, political rhetoric, fake news and extremist groups, it’s not often the individual where we have the leverage to change things but rather the rules of the game. Humans are pretty-smart and collectively, we’ve done amazing things. We’ve transformed the planet, cured diseases, and minimised hunger. On the other hand, we’re susceptible to an awful lot of craziness. The reason that not all of us are crazy all of the time isn’t so much that we’re so rational, but we have (over time) developed institutions that keep our biases and craziness in check. We all want to win arguments with good stories, but the rules of the game are that you’ve got to test your theory against evidence – you have to submit your ideas to editing, fact checking and peer review. Instead of encouraging people to just blurt-out what’s in their mind, we should be encouraging people to ponder, to test. We need to make our collective output more rational by having our beliefs tested and filtered by various checks. That’s how we- as societies- have managed to understand the world and control nature to our benefit, and hopefully nature’s benefit too.
You can’t just count on every individual being smarter if they’re in an ecosystem that doesn’t value the rationality of the ultimate output.
Just stopping and thinking twice at the individual level or not publishing an article before showing it to others to see if it makes sense… these filters may slow things down, but probably to all our benefit.
People often ask me if I get abuse and hate mail because embrace allegedly controversial positions. Interestingly… I don’t so much on email, its very, very rare. I get some people sending me critiques which is great, but rare that I get anything nasty. I open twitter however, and the comments section is just filled with insults and obscenities. Just that extra step of looking up a guy’s email address and composing the email slows us down enough to consider what we’re doing. The classicist Mary Beard famously engaged some of her most vicious trolls and a lot of them were taken aback. It just didn’t occur to them that there was a real human being at the other end, and she really go the better of them simply by saying ‘why are you saying these things about me?’ – the requirement to stop and think, that can be a civilising force.