Belbin, Big Five, and the trouble with decimal points
An Apology to Dr. R. Meredith Belbin
A thesis with a mission
Quite some time ago—back in 1997—I wrote a monograph to fulfill one of the requirements for earning the degree of Cand. Psychol., the Norwegian professional degree required to practice as a clinical psychologist. Its title is R. Meredith Belbin’s Team Roles viewed from the Perspective of the Five-Factor Model of Personality.
I could go into painstaking academic detail about what I did. But I won’t—because you can read it for yourself if you’re interested.
Suffice it to say, I tried to show that Belbin’s model of team roles could be translated into the language of another model—the Five-Factor Model of personality—which actually has scientific merit. If Belbin’s model can be described using the Five-Factor Model, then perhaps it too deserves to be taken seriously.
That was my thinking, anyway.
Meeting the man himself
After completing my degree, I went straight to the next Belbin Conference in Cambridge, where I met Dr. Belbin himself. I gave him a copy of my thesis, hoping—naively, I now realize—that he’d read it and suddenly see the errors of his ways.
He didn’t.
He read it, and we sat down to discuss it. Except there wasn’t much of a discussion. Dr. Belbin said (and I quote from memory):
“Your monograph is scientific and thorough and … [more nice words] … and completely superfluous.”
Then he sighed.
Then he said:
“People keep saying, ‘If only this Belbin fellow were a psychologist!’”
(He slammed his fist on the table.)
“But I am a psychologist! I earned my PhD in gerontology in 1945! I’m just not interested in measuring personality to eight decimal places.”
A contradiction at the heart of it
Later I learned this was typical Belbin. “I’m not interested in psychometrics. I’m just measuring people.” Which is, of course, a contradiction. But this, I’ve come to realize, is a caricature of what Dr. Belbin is saying. Because psychometrics isn’t just about how we measure—it’s also about what we measure.
The limits of precision
Since then, I’ve spent a good portion of my professional life measuring people. And yes, our instruments have gotten even more precise. These days, we can measure personality traits to nine decimal places if we really want to. But what we’re mostly measuring are theoretical constructs.
And here’s the thing: a concept is an abstraction. A construct. It’s something we can talk about, quantify, even run regressions on—but it doesn’t necessarily correspond to something solid and observable in the real world.
Take extraversion. We can quantify how extraverted you are. We can graph it, analyze it, compare it. But what then? What does that number actually tell us? Sure, it gives us a statistical sense of how you’re likely to behave over time—and we’re often right. But it doesn’t tell us exactly what you’ll do in any given context. Because we don’t go out into the world and document what extraverts actually do at various levels of extraversion. Not really.
What I did in my monograph was armchair research. I never had to leave my desk. If I wanted to make the findings practically useful, I would’ve needed to spend time in the field—interviewing, observing, coding behavior, possibly funding a team of researchers.
That’s where a lot of personality research still sits—at desks. In labs. At the other end of a spreadsheet. And I get it. That’s what researchers are paid for. But if we want research that’s truly useful, we have to step outside. Into messier, more expensive terrain. And most researchers don’t have an incentive to go there.
What really matters
At the time, I was genuinely disturbed by Dr. Belbin’s reaction. I thought he would welcome a rigorous, scientific validation of his model. There was so little of it back then. I won’t say exactly what I thought—but you can probably guess. I was disappointed.
Years later, I’ve come to see things differently.
We already measure personality with enough decimal places. That’s not where the next step lies. The future of meaningful research isn’t in more precise instruments—it’s in richer contexts. It’s in observing real people, in real teams, doing real things.
If that’s what Dr. Belbin is saying—and that’s what I, in hindsight, think he’s saying—then he’s right.
