Knowing what we don’t know

Courtesy of Alan Jacobs, here is a terrific article by Errol Morris about a fundamental but largely ignored truth: there is a critical difference between knowing that you don’t know something and not knowing that you don’t know something.

Morris came across a paper with a wonderful title, “Unskilled and Unaware of It: How Difficulties of Recognizing One’s Own Incompetence Lead to Inflated Self-assessments.” It was written by two psychologists, David Dunning and Justin Kruger [emphasis added throughout]:

Dunning and Kruger argued in their paper, “When people are incompetent in the strategies they adopt to achieve success and satisfaction, they suffer a dual burden: Not only do they reach erroneous conclusions and make unfortunate choices, but their incompetence robs them of the ability to realize it.  Instead, they are left with the erroneous impression they are doing just fine.”

It became known as the Dunning-Kruger Effect — our incompetence masks our ability to recognize our incompetence.

Morris contacted Dunning to ask him a few questions:

DAVID DUNNING:  Well, my specialty is decision-making.  How well do people make the decisions they have to make in life?  And I became very interested in judgments about the self, simply because, well, people tend to say things, whether it be in everyday life or in the lab, that just couldn’t possibly be true.  And I became fascinated with that.  Not just that people said these positive things about themselves, but they really, really believed them.  Which led to my observation: if you’re incompetent, you can’t know you’re incompetent.


DAVID DUNNING:  If you knew it, you’d say, “Wait a minute.  The decision I just made does not make much sense.  I had better go and get some independent advice.”   But when you’re incompetent, the skills you need to produce a right answer are exactly the skills you need to recognize what a right answer is.  In logical reasoning, in parenting, in management, problem solving, the skills you use to produce the right answer are exactly the same skills you use to evaluate the answer.  And so we went on to see if this could possibly be true in many other areas.  And to our astonishment, it was very, very true.

ERROL MORRIS: Many other areas?

DAVID DUNNING: If you look at our 1999 article, we measured skills where we had the right answers.  Grammar, logic.  And our test-subjects were all college students doing college student-type things.  Presumably, they also should know whether or not they’re getting the right answers.  And yet, we had these students who were doing badly in grammar, who didn’t know they were doing badly in grammar.  We believed that they should know they were doing badly, and when they didn’t, that really surprised us.

ERROL MORRIS:  The students that were unaware they were doing badly — in what sense?  Were they truly oblivious? Were they self-deceived?  Were they in denial?  How would you describe it?

DAVID DUNNING:  There have been many psychological studies that tell us what we see and what we hear is shaped by our preferences, our wishes, our fears, our desires and so forth.  We literally see the world the way we want to see it.  But the Dunning-Kruger effect suggests that there is a problem beyond that.  Even if you are just the most honest, impartial person that you could be, you would still have a problem — namely, when your knowledge or expertise is imperfect, you really don’t know it.  Left to your own devices, you just don’t know it.   We’re not very good at knowing what we don’t know.

ERROL MORRIS:  Knowing what you don’t know?  Is this supposedly the hallmark of an intelligent person?

DAVID DUNNING:  That’s absolutely right.  It’s knowing that there are things you don’t know that you don’t know.

At the risk of being pedantic, let me point out that at the end of the interview Dunning says two important things which he doesn’t distinguish very well. First, he points out that it is very difficult to know exactly where the gaps lie in your knowledge; put another way, it is difficult for us to keep track of which of our operating assumptions are grounded in knowledge and which are based on sheer guesswork, received wisdom, wishful thinking, and so on.

However, when Morris asks him if such an ability is the hallmark of an intelligent person, in agreeing Dunning actually puts forward a different hallmark: an awareness that there are gaps in your knowledge. It’s not enough to be good at keeping track of what you don’t know. You have to be humble enough to acknowledge that gaps are the default state, that what you actually know is vastly outweighed by what you don’t know. And you have to be vigilant about staying clear on what fits into which category.

I think this is more or less what Socrates meant when he said, “The only true wisdom is in knowing that you know nothing.” The statement by itself is misleading, but the context makes it clear. Since I’ve written about this before, I’ll resort to quoting myself:

Part of the accusation against Socrates was that he purported to be wise, and was misleading the youth of Athens and otherwise raising a ruckus via his wisdom. His response was that in fact he had no wisdom, and that the rumor that he considered himself wise was baseless.

He went on to trace the source of the rumor to a prophecy by the oracle at Delphi, who once proclaimed that Socrates was the wisest of all men. Socrates was astonished, knowing he had no wisdom, and alarmed, not wanting such a reputation. He figured the quickest way to disprove the prophecy was to find someone wiser than he was. The search for such a person didn’t go well, though; each time he found folks who had reputations for being wise—politicians, philosophers, poets, artisans—Socrates’ questioning of him revealed that in fact there was no wisdom there at all. (Which didn’t please the politicians, philosophers, poets, and artisans, turning them into enemies who floated calumnies against him, leading to his false reputation for wisdom.)

The puzzle remained: was the oracle correct? Giving the oracle the benefit of the doubt, Socrates finally understood the prophecy to mean that he was the wisest of men simply because he, unlike the rest, understood that he had no wisdom at all.

In saying that he has no wisdom at all, I think that Socrates is using excessive modesty as a rhetorical device; clearly he thought he had wisdom to share with others. But his wisdom is actual wisdom because he has done the hard work of identifying and junking the baseless assumptions that others pass off as wisdom, thereby making room for the truth.

I will often challenge my children to defend a claim they make, especially an offhanded one, not because the claim is false—it may be true—but because I don’t think they know it to be true. And even so I am not insisting that they speak the truth, but that they speak carefully. I want them to develop the awareness that Dunning speaks of, as well as the humility and consideration needed to keep silent when one has nothing useful to say.


4 thoughts on “Knowing what we don’t know

  1. How do you challenge your children to defend a claim that they make? What makes a statement valid… does it have to be Biblical to be true, or they have to have some firsthand experience, or…?

  2. Angela,

    How do you challenge your children to defend a claim that they make? What makes a statement valid… does it have to be Biblical to be true, or they have to have some firsthand experience, or…?

    We need to distinguish between issuing the challenge and grading the defense.

    I challenge my children by saying something along the lines of “Why do you say that?”, and I generally issue that challenge when I have good reason to think that they don’t have a good answer. And my goal is to get them to realize that they don’t have a good answer, i.e. they are just shooting their mouth off.

    As for dealing with wrong thinking, or training them to defend their claims right or wrong, I try not to do that via direct confrontation. The power equation is too lopsided. I don’t think it’s fair to ask them to argue it out with me, their father and a much older man, and I don’t want to encourage cockiness by treating them as a peer. Mostly we will just talk through the issue, with me telling them what I think.

  3. There is a certain amount of knowledge required to know exactly what you do not know. For example I know that I can’t replace a transmission in a truck. However I am not even entirely sure of the exact things I do not know which cause this.

  4. Why do we believe what we believe? We believe what we believe because we believe we are correct in our beliefs.

    Why would one choose to believe what one knows one is incorrect in believing?

    We are all proud, too proud…



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