Myers‒Briggs Type Indicator, StrengthsFinder 2.0 and other personality type tests have become commonplace tools in many workplaces. But do they really tell us about personality traits, and can they be helpful personally and professionally? These are among the questions Cambridge University professor Brian Little explores in his new book Me, Myself and Us: The Science of Personality and the Art of Well-Being.

Wharton management professor Adam M. Grant recently interviewed Little about personality traits and his new book when he visited campus as a guest lecturer in the Authors@Wharton series.

An edited transcript of the conversation follows.

Adam Grant: It is not every day that I get to interview my mentor on camera. Brian, for starters, tell us about your book.

Brian Little: The book actually grew out of experiences you and I had at Harvard a few years ago. I had stumbled upon the opportunity of teaching a class. As the class went on, after a few days, it got bigger. And then bigger. I thought, “Oh, isn’t this wonderful. All of the students are coming.” But in fact, it was the ex-boyfriends of some of the students in the class who were coming because there seemed to be something that touched their hearts and let them think that there was something of value here beyond the classroom that may actually influence their lives.

[Then] the parents would come, and belligerent uncles and things like that. In about the year 2000, I thought that it would be a good idea to write a book that would engage with those people who weren’t taking Personality Psychology as an academic course but as a way of illuminating their lives and understanding the people they love and work with.

“I am — and this surprises my students — a very introverted person…. But … I will act as an extrovert when I’m lecturing.”

Grant: I remember sending every one of my roommates — actually forcing them — to take your course.

Little: I remember that, too.

Grant: I, of course, got repaid for that by them coming back and diagnosing all of my problems and pathologies, which I supposed I deserved. But one of the most interesting things we learned about in the course was this idea of free traits. Talk to us about that.

Little: The set-up to this is that right now the study of traits is in the ascendancy. There was a time when trait psychology was in deep trouble. It was as a result of Walter Mischel’s 1968 book Personality and Assessment, where he drew the conclusion that stable traits of personality were non-existent. He has modified that position more recently. But at the time, it dealt quite a blow to the field. In the ensuing years, trait psychologists — those who study the Big Five dimensions of personality — regained ascendancy. It has become the most active field of personality research.

But I have some concerns about it. Let me tell you the essence of my concerns about traits. The Big Five dimensions spell out the acronym OCEAN: Openness, Conscientiousness, Extroversion, Agreeableness and Neuroticism. Many who study traits believe that we can be adequately and effectively described by our status on those five dimensions. I think there’s some truth to that. I lecture, as you know, about these. In the book, I spend a couple of chapters talking about these relatively fixed traits of personality.

Perhaps the most topical — a hot topic — is that of extroversion. [That is] largely the result of our mutual friend Susan Cain’s book Quiet, which I strongly recommend your viewers to read, except for chapter nine. Chapter nine is about the machinations of a strange little Canadian guy who taught at Harvard for a few years who used to hide from the students in the washroom. I explain that behavior — I guess it’s somebody very similar to me — by invoking the notion of free traits. I am — and this surprises my students — a very introverted person. I’m off the bottom of the scale as an introvert.

But because of something that matters dearly to me — which is the personal project of professing with passion and alliterating in a public place — I will act as an extrovert when I’m lecturing. I’ll speak loudly as you do when you’re addressing a class at the beginning. I’ll gesticulate wildly. I hope not too wildly because I think we need not to be overbearing when we’re professing — but we need to keep students awake at eight in the morning. So, I act like that, and I’m engaged in what I call a “free trait.” Much of Me, Myself and Us, deals with how free trait behavior differs from trait behavior or fixed trait behavior.

The free trait of, in my case, pseudo-extroversion plays out by advancing my core project, which is engaging with my students, whom I love. It advances that core project in ways that will redound to my benefit. But there are potential costs. I’m not rare. Many people act out of character through free traits. There are highly agreeable people who for all of the month of March act out of character because they are trying to get a better place for their mother in a care home. They have to bash down the doors of administrative resistance and advance a project — take care of Mom — that enjoins that person to act in a disagreeable way.

We can do this. It’s call “professionalism.” It’s also called “love.” But we may pay a price if we act out of character for a long period. The empirical evidence on that is still growing. I’d say right now it’s mixed. But there is growing evidence that acting in ways that go against your first nature, as I call it, may be problematic at the same time as it advances our well-being.

Grant: When we take this into the workplace, one of the things that you touched on is this idea that we all have personal projects, these commitments that we make to courses of action that matter deeply to us. How can an understanding of the personal projects of the people I work with enable us to work more effectively together?

“Many people act out of character through free traits…. But we may pay a price if we act out of character for a long period.”

Little: It offers an explanation for their action in ways that simply monitoring or attending to their outward and visible behavior would not. We can watch a person who is engaged in a pattern of behavior that makes us say that person is neurotic, and therefore, I may rate that person down because he appears to be anxious when dealing with clients. But in fact, that person may be engaged in a personal project that is entirely explicable by noting what that core project is. That core project may be, “I’ve got to pick up my kid. He’s waiting outside in the cold. I know I’m a little distracted, and I may give the appearance of not understanding what’s going on in this financial meeting.”

Once you understand what a person’s core projects are or even ask a person, “How is it going, David?,” it puts us in a position where we can actually treat humans as humans. That to me is going to pay enormous benefits in the long term.

Grant: You take a stand in the book about some more effective and less effective ways of thinking about personality. And one of the more popular ones of course is the Myers‒Briggs Type Indicator [MBTI], which you’ve been observing for almost half a century now. Where do you stand on that as an assessment instrument?

Little: In the book, I take a few whacks at the MBTI. But then I come back and look at the function that it serves of getting people to talk about individual differences and personality. That’s good. It opens up a way of thinking about each other and thinking about ourselves. The validity and reliability leave a lot to be desired from a hard-nosed psychometrist’s perspective. But I think it does serve a purpose.

Unlike some of my students who would totally castigate it, I would say that there is room for that, but we need to be cautious. The best example is by invoking free traits again. People who walk around with a “I am extrovert” or “I’m an intuitive introvert” sometimes reify it so much that they actually think that there’s a kind of neurological circuit in the brain that declares itself as “I am an extrovert” or “I am an introvert.” That is palpably false. By cordoning ourselves off from refutation, by claiming as a core sense of our identity that “I am an extrovert” or any of the other Myers‒Briggs designations, we reduce our degrees of freedom to be fully human.

Adam — just let me use a random name — may be quite introverted but he could act out of character and advance the core projects that matter to him such as his students at Wharton. And all that is important. But if he just walked around with “I am an introvert” on his forehead the degrees of freedom would be severely curtailed.

Grant: Probably my favorite chapter in the book was the one about self-monitoring, which I think captures some of the fundamental questions around when do some people essentially end up adapting to the situation, whereas others choose to say, “This is who I am.” Talk to us a little bit about what we should know about self-monitoring.

“Once you understand what a person’s core projects are … it puts us in a position where we can actually treat humans as humans.”

Little: Self-monitoring boomed in the 70s with Mark Snyder’s work. I revisit it and try to cast it in terms of the whole issue of fidelity to our beliefs and authenticity and the current debate about authenticity. High self-monitors are those who will adapt themselves to the current situation. So, at a party, they will act “party.” At a funeral, they will act funereal. The high self-monitors will shape their behavior to accord to the situation. The low self-monitors will act on the basis of their own beliefs and their own personality traits.

If they are feeling particularly funereal at a party, a low self-monitor says, “Well, that’s the way I am. I like to be glum at a party.” The high self-monitor would say, “Good God, it’s a party. Why are you standing by the coffin staring at it? You’ve got to shape yourself up by adapting to the situation.” To which the low self-monitor says, “I don’t get it. Why? People who are stand-up chameleons have no character.” Those who are high self-monitors will say, “Those who are rigidly themselves have no humanity because they are insensitive to the needs of others.”

The conclusion I reach after giving a bunch of the research in this area is that I think, on balance, high self-monitoring is very adaptive. As long as it doesn’t blend itself into what’s called “aesthetic character disorder” where you are so imbued with the demands of the situation or the delights or the aesthetics of the situation that you will act in ways that go against your core values. There have been some politicians who have been accused of having aesthetic character disorder. That it, in turn, blends into a kind of insensitivity that can be downright dangerous.

Grant: In closing, we often think that great leaders are great teachers. It would be great to hear a little bit of wisdom on what we can learn from one of the true great teachers. You won Canada’s highest award for university teaching. You are one of the favorite professors of the Harvard class every year you’ve taught there. What can leaders learn from the way that you teach in the classroom?

Little: First, thank you. I’ve been giving a lot of thought to this recently. Part of it was stimulated by your own work and by the evidence that introverts are good listeners. That balance between talking and listening, asserting and reflecting and the capacity to shift between them seems to be really critical.

I don’t think that there is a one-size-fits-all personality type for leaders. There are a diverse set of factors, the key aspect of which is the ability to choose, select and empower the most virtuous forms of your own personality; the capacity to listen; the capacity to say, “I’ve listened, I must act”; the capacity to show alacrity, moving in and dealing with the situation instead of puzzling all Hamlet like and not being sure. But overdoing one or the other leads to problems both personal and political.