Cromwell’s Rule

CromwellI beseech you, in the bowels of Christ, think it possible that you may be mistaken.

~Oliver Cromwell, in a letter to the Synod of Scotland

I remember the day I first learned to ask a crucial question during a conversational argument. Locked in a fervent discussion about religion, my interlocutor and I had logged hours of circling around the same issues. I despaired of making any headway. Then it dawned on me—the question! It was this: “Do you think it is possible that you’re wrong?” He answered “no,” and I politely ended the conversation.

Of course, I’ve put the same question to myself: “Is it possible that I’m wrong on this issue?” And I have to say, “yes.” Doesn’t this seem reasonable? After all, the evidence of my fallibility grows daily. I think this assumption, that one could be wrong, is crucial to any productive argument. The only exception being an argument about the fact of my own current existence—if I’m wrong about that one, then all (my) bets are off. Literally.

Cromwell’s Rule

Dennis Lindley (1923-2013), a British statistician, coined the term “Cromwell’s Rule” regarding this crucial assumption. Lindley was concerned about formally calculating probabilities rather than persuasive argument, but his “rule” helps make a good point. You should never assume (unless something is true by definition, like “2+2=4” or “all unmarried men are bachelors”) that something is impossible (or necessarily true), because it renders you practically immune to new evidence to the contrary. Rather, you should leave a little epistemic space for even extremely unlikely scenarios

Doctor WhoHere’s an illustration. In an episode of the popular sci-fi TV show Doctor Who (“Midnight”), a group of tourists travel via ground shuttle to visit the famed emerald waterfalls of the planet Midnight. When the shuttle stalls and knocking sounds are heard on the hull, a scientist on board (Hobbes) tries to reassure them that no living thing could be knocking on the hull because no living thing could survive the lethal “galvanic radiation” that bathes the planet’s surface. As the evidence mounts that the shuttle is under attack by an intelligent being, the scientist simply cannot bring himself to even admit this possibility, despite its being obvious to everyone else aboard. Hobbes remains trapped in his fundamental assumption about life on Midnight, unable to assimilate even the evidence of his own eyes and ears.

Sandy Heads

Religious skeptics, believers and political pundits often fall prey to this same mistake. We could call it intellectual pride, hubris, or plain old stubbornness. Utterly convinced of our position, we blockade ourselves against new evidence like the proverbial ostrich with its head in the stand. Even if it turns out that our belief is true in this instance, the habit of ignoring Cromwell’s Rule makes us vulnerable to error in the future. Good thinking and arguing, for those who are genuine truth-seekers, must include some openness to our own fallibility.


How to Lose an Argument

I only hate losing when it comes to things I’m good at. I’m happy to concede a basketball game or a tennis match. But I hate losing arguments. Since childhood, I’ve relished a good adrenaline-surging verbal exchange. It’s fight argumentprobably one part genetic, one part environment. You know how most families have a variety of personality types who complement and balance one another? My parents , me and my sister were all hyper-assertive, stubborn fighters. You adapt to survive. You learn to like it.

My wife, on the other hand, hates conflict. So that has been challenging. And just as she thought I might be mellowing out a bit, I went and got a PhD in arguing. I probably laughed more than most people when I read humorist Dave Barry’s essay, “How to Win Arguments.” He writes,

I argue very well. Ask any of my remaining friends. I can win an argument on any topic, against any opponent. People know this, and steer clear of me at parties. Often, as a sign of their great respect, they don’t even invite me. You too can win arguments.

Barry tenders such advice as, “make things up,” “use meaningless, but weighty-sounding words,” and “use snappy and irrelevant comebacks.” And though Barry’s piece is satire, he gets the point across in a witty, indirect way: don’t be an ass. I wish I could say that I’ve reigned in my argument demon sufficiently and in time to avoid passing it along to my children. Now I’m just hoping one of them becomes a cutthroat attorney and cashes in on their pugilistic legacy.

argumentBut I suppose I have made a little progress, halting though it’s been. So here’s a bit of what I’ve learned. First, stop trying so hard to win. Good arguments don’t have to be winning arguments. As soon as you turn it into a battle or a competition, someone has to lose, and there is no one harder to persuade than the person reeling from your verbal violence. And isn’t persuasion what we’re after?

A little terminological clarification might help illuminate things here. The word ‘argument’ carries multiple meanings. One is relational. It is a (hopefully civil) discussion between two or more people who disagree about some point. Despite what you see on TV, or on the hidden cameras you’ve installed in my home, arguments don’t require yelling, insults and emotional outbursts. The other sense of ‘argument’ is a collection of ideas, put together in a logical way to support a conclusion. So, in this sense, we don’t have an argument with someone, we give an argument to someone. And since logic and truth reign supreme in a good argument, emotions, egos, and agendas must be set aside as much as possible. (Now, if you are a particularly adept ass, you can throw this in people’s faces. There’s nothing a highly-aggravated person loves to hear more than, “calm down!”) Here are some tips that promote good arguments, in both senses:

  • Believe you may be wrong – the foundation of all helpful dialogues; don’t even bother without it
  • Take the other person seriously – respect, seek to understand
  • Be a truth-seeker – are you honestly after truth, or just out to make your point?
  • Do your homework – don’t just expect people to take your word for it; have some evidence or research to back it up
  • Assertions vs. arguments – just saying “Joe is a moron” is not an argument
  • Know when to walk away – if you or they get too angry or disrespectful

SocratesIf I could offer just one word, it would be humility. Humility of character and intellect. Socrates himself claimed that what set him apart from other people was that he alone realized how little he knew. Perhaps this is what motivated his method of asking questions (often called the “Socratic method”) in a dialogue rather than launching into a lecture or a monologue. Because of his humility and his logical, conversational approach, Socrates persuaded people. Well, except for the Athenian officials who executed him.

crispy foodSo instead of trying to win, think about persuasion as your goal. Just as “revenge is a dish best served cold,” persuasion is a dish best served warm and crispy with tasty seasonings and a colorful garnish. It may be cliché to talk about “win-win scenarios,” but when you and your conversation partner move closer to the truth through argument, everyone wins.