Twelve years ago, I wrote a post on this blog about the “10,000 hour rule” that Malcolm Gladwell promoted in his book Outliers. Gladwell claimed that 10,000 hours was the “magic number of greatness” – that 10,000 hours of practice was required to excel at an activity.  The author of the study that Gladwell cited as supporting this claim said that Gladwell misinterpreted the study’s results. Others have pointed out that the “10,000 hour rule” is misleading in suggesting that the total time spent on an activity is the only predictor of success. It doesn’t take into account other variables that might affect skill development, such as deliberate practice, innate or acquired talent, the age at which someone begins the activity, and access to appropriate equipment, coaching, and training sites.

While there are debates about exactly how much effect some of these variables have, it’s clear that Gladwell took the 10,000-hour figure out of context, and also skimmed over some important details that are necessary to fully understand how skill development works.

The post I wrote on the “10,000-hour rule” is by far the most popular post ever on this blog. That shows how interested people are in what Gladwell says. It also shows the importance of looking closely at his claims – to see what evidence he cites to support them, and to see whether experts on the subject agree with his interpretations.

This is not to say that only experts can discuss these kinds of topics. Sometimes an outsider can see details or trends that experts don’t notice. And there’s always a place for a writer who’s not a scientist or researcher to explain research and its outcomes to a general audience. But the writer needs to get the details right, and not simplify things to the point where important pieces of information are omitted.

Gladwell has just released a new book, Revenge of the Tipping Point. One of its chapters is about a new “magic number”: the “Magic Third”. This, Gladwell claims, is the number of minority members in a group that’s necessary for the minority to be accepted as part of the group. I’m going to look at this claim in detail because this general subject (organization and group dynamics) falls into my own area of professional expertise, so I have some familiarity with the relevant research.

The chapter subtitle of “The Magic Third” is a quote from one of Gladwell’s interviewees: “I would say, absolutely, there is some tipping point in my experience”. Notice that the quote doesn’t mention the “magic third”, or any number for that matter; it only says that there is a demographic tipping point which causes group dynamics to change. This type of change is well-documented in research on the effects of group composition. The fact that group dynamics change if group membership changes also won’t be a surprise to anyone.

Gladwell starts out by discussing US urban demographics in the 1950s and 1960s, and how neighbourhoods evolved into being primarily inhabited by Black or by White residents. I don’t know the research on this topic well enough to comment on whether Gladwell presents these situations accurately. But then he turns to research that I am familiar with: the work of Rosabeth Moss Kanter, a Harvard Business School professor who conducted some of the pioneering studies on the experiences of women in organizations, particularly at the managerial level.

Gladwell discusses a study that Kanter conducted in the 1970s, in which she examined how “dominants” and “tokens” interacted in organizations. The “tokens” in this case were women employees, who were vastly outnumbered by men. Kanter’s research suggested that groups with skewed proportions, where there were many group members of one kind but very few of another kind, led to the “dominants” misinterpreting what the “tokens” did, or why they did it, or what they were really like. That made it difficult for the “tokens” to be understood or accepted by the “dominants”, no matter how well they performed their jobs. (Kanter explains this phenomenon quite accessibly in this animated video.)  Gladwell then proceeds to follow up on Kanter’s suggestion in the study that “exact tipping points should be investigated”: i.e. how many “tokens” are needed in a group or organization for them to no longer be perceived as “tokens”.

His first source of data is a 1959 quote from community organizer Saul Alinsky about “white flight”, in which Alinsky says, “Everyone who has thought seriously about the matter knows that there must be a formula of some kind”. Gladwell extrapolates sections from this quote to summarize it as “everyone who has thought seriously about the matter talks about a numerical percentage.” This isn’t exactly what Alinsky said – he also mentioned “ratios” and “quotas” – but Gladwell also overlooks that Alinsky is talking about a specific situation (urban housing and communities) and the interactions between two specific demographic groups (Black residents and White residents). What happens in this setting may or may not be what happens in other contexts or with other demographic groups, but Gladwell doesn’t mention that. Gladwell runs through quotes from other commentators from the same era before saying:

In the end nearly everyone was in agreement. Something dramatic happened when a once-insignificant set of outsiders reached between one-quarter and one-third of the population of whatever group they were joining. Let’s pick the highest end of this range and call this the Magic Third. (p. 121)

Gladwell doesn’t explain why “the highest end of this range” is the appropriate proportion to choose – especially when two of the four sources he’s cited at that point have suggested lower percentages – but he then goes on to assert that “the Magic Third turns up in all kinds of places”. He references a study of 50 women members of corporate boards who discussed their experiences of being marginalized as a demographic minority. He quotes from the study: “The magic seems to occur when three or more women serve on a board together” (p. 123), and proclaims, “Three out of nine people. The Magic Third!”

The “nine” comes out of nowhere. These recent data show that boards of large US companies have anywhere from fewer than six members to more than 12, and that the average board size is actually close to 10 members. It’s also important to acknowledge that nearly every board meeting or discussion isn’t limited to the board members; usually executive staff or other organizational members with relevant expertise are participating, even if they don’t have a formal role in the board’s decision. Three or more women may be a large enough number to make a difference on a board, but there’s no guarantee that any board-related group they’re participating in will only have nine members.

Vicki Kramer, the lead author of the study on boards that Gladwell cites, disputes Gladwell’s interpretation of the study, and wrote a letter to the New York Times Book Review about it. The letter says, in part,

I recognized the quotes and some of Gladwell’s points, but not the concept of a ‘Magic Third’. We used the word ‘magic’ to describe what happens when three or more women serve on a corporate board, but explained, ‘It is having three or more women on a board rather than a certain percentage that makes the difference.’ We wrote that ‘three women constitute a significant percentage because a typical board has between nine and 12 directors’….Our study focused on the largest for-profit public companies, where nine to 12 was typical.

Kramer also says:

But even in boards with 30 percent women directors, that presence alone does not guarantee inclusion in leadership positions or on important committees.

This comment highlights a critically important part of group dynamics that Gladwell disregards. Not all group members have equal authority or responsibility, depending on the purpose and composition of the group. One way that majorities in groups can exclude those who are perceived as minorities, even if there’s more than a few of them, is to not give them roles with greater power or influence.

Grasping for evidence to prove that the “Magic Third” is a thing, Gladwell then talks to two women involved with initiatives to increase the number of women on corporate boards. One says she “isn’t sure” that three is the right number, but says that “in my gut is maybe three is the magic number, because I think that at three, you feel enough.” The other (the one quoted in the chapter’s subtitle) is paraphrased by Gladwell as saying that “three was what made the biggest difference”. He then extrapolates that interviewee’s experience of watching a board transform as more women joined into a reason why the “Magic Third” is “magic” (his italics, not mine).

Then Gladwell makes a big leap. “I think we can go one step further. I think we can call the Magic Third a universal law. (Or at least something very close to universal.)” (p. 125). Two peoples’ lived experiences and the selectively interpreted results of two studies don’t come anywhere close to demonstrating a “universal law”.  For context, I did a couple of searches in the Academic Source Complete database of published peer-reviewed research, using the search terms “minorities”, “group dynamics”, and “groups or teams” – and came up with between 900 and 1200 articles on these topics, published between the mid-1970s and now. The questions Gladwell is exploring have been the subject of a lot of research, and he hasn’t even begun to scratch the surface of what that research shows. Here’s just a few of the other factors affecting group dynamics that he ignores:

• Intersectionality: the reality that everyone has multiple social identities, and those affect how someone is perceived or treated. For example, if the majority of a group’s members are White people that all graduated from the same college, a Black group member who also graduated from that college may be accepted by the majority because of that shared characteristic, even though they are a racial minority within the group.
• The importance of an individual’s own skills and knowledge. If a person that’s part of a demographic minority in a group possesses specific abilities, and no one else in the group has those abilities, that person may be accepted by the majority of the group if the group needs those skills to function, or to function effectively.
• The tasks the group has been given, or the reason that the group has been formed. The divisions between “dominants” and “tokens” may be more pronounced if the group has difficult tasks, or if the group has been formed because of a controversial issue.
• The length of time a group works together. As majority and minority group members get to know each other better, they may perceive fewer or more differences between them, depending on whether their interactions are positive or negative.

Effectively integrating demographic minorities into groups is far, far more complicated than just having minorities be one-third of the group’s members. The additional factors I listed above are not difficult to explain; anyone who has been part of a group will recognize at least some of them, because they’ve seen them happen. But in his quest to push the idea of the “Magic Third”, Gladwell ignores them.

The evidence in the remaining part of the chapter also doesn’t support the idea of a “Magic Third”.  Gladwell discusses the work of a researcher, Damon Centola, who ran experiments in which groups of participants assigned names to photos of individuals, and then got feedback on whether their choices matched others’ choices. Once a group had reached consensus on “appropriate” name choices, new participants who had been instructed to act as “dissidents” joined the groups, with the intent of getting the original group to change their consensus. It took between 20% and 25% of group members being “dissidents” to make the changes happen.

Twenty-five percent is clearly less than the “Magic Third”, but Gladwell sidesteps that problem by saying, “The idea that there is a magic moment somewhere between a quarter and a third is different. It practically begs us to intervene” (p. 128). So is the “Magic Third” a “universal law” or not? Gladwell then presents data from a study correlating standardized test scores with the racial composition of elementary school classes. Those results indicate when 25% or more of a class is from a minority group, the gap in test scores between students from minority and majority groups disappears.

The “Magic Third” is looking less and less “universal” by now, but Gladwell evades that with “I think it’s important not to make too much of [the researcher’s] findings. They are just about elementary- and middle-school performance on a single metric – one kind of standardized math achievement test” (p. 129). Every other piece of evidence he’s cited to support the “Magic Third” is also from studies conducted in specific settings with specific demographic groups, but apparently the results of this one study are not that important. Why? He never explains.

He then mentions “a news outlet in 2022” calculating that 60 of the CEOs of Fortune 500 companies are of South Asian descent (he doesn’t give a citation, but he appears to be referencing this story). Sixty out of 150 is 40%, so what this has to do with the “Magic Third” is not really clear. Gladwell claims “something fundamental changed in the way American culture viewed Indian Americans”, but doesn’t explore what changed or what caused it to change.

After revisiting one of the examples of urban residential integration that opened the chapter – and now stating that the possibility of exceeding “the Magic Third” was the reason that community didn’t become more racially integrated – Gladwell finishes off with some generalizations about tipping points. “The reason to avoid acknowledging the simple solutions offered to us by tipping points is that, in the end, the solutions aren’t really that simple” (p. 135) – this despite him spending most of the chapter pushing the simple idea of the “Magic Third”.

One would hope that, after the lengthy and detailed criticisms of the “10,000 hour rule”, Gladwell would be more careful about how he interprets and presents research findings. Sadly, that doesn’t seem to be the case. Now two of the researchers (first Ericsson, and now Kramer) whose work Gladwell has cited as key sources for his “rules” or “laws” have said that he’s misinterpreted the results of their research. That pattern can’t be attributed, as Gladwell has so often claimed, to his books not being for everyone and written for a general readership, not academics or scientists.

This ongoing problem may be from Gladwell being careless, or being too concerned with simplifying, or genuinely misunderstanding how to interpret research results (which seems unlikely, since he’s apparently been reading academic research for more than two decades). But hey, the “Magic Third” is easy to remember, and if you don’t look at it too closely, it seems like a reasonable idea. When corporations are paying Gladwell $350,000 to speak at their events, something like the “Magic Third” is exactly the sort of digestible and actionable takeaway that they want.

Now by this point, you, the reader of this post, might be saying: who cares? Who cares if it’s 20% or 25% or 33% or whatever amount of representation that changes a group? My reason for going into this much detail about Gladwell’s claims is simple: people listen to Gladwell, and they believe what he says. He can airily dismiss criticism of his work with statements such as “If I turn out not to be right, I’m not devastated” – but that grossly underplays the potentially negative impacts of his weakly supported “laws” and “rules”.

I’ll give one example, related to the “10,000-hour rule”. A book about parents of young hockey players (I wrote about the book here) describes not only the practical difficulties of getting in 10,000 hours of practice in that particular sport, but also how coaches, trainers, and hockey schools are profiting off parents mistakenly believing that if their children don’t put in 10,000 hours of effort, they will never be successful in the sport.

Think about what a similar mindset would look like in applying the “Magic Third”. If an organization’s leaders believe that all a group needs to be more effective or inclusive is one-third of the group’s members being a minority, they’re going to find as many members of that minority as they need, and put them in that group. The type of group won’t matter, the context of the group won’t matter, the tasks of the group won’t matter – just achieve that “Magic Third” and everything will be fine (and they’ll also look good for encouraging minority representation). If you Google “Magic Third”, you’ll see that business media outlets, bloggers, and podcasters are already promoting this idea. But so many things could go wrong with this approach, and the outcomes could be tremendously damaging to the members of the group, to the leaders, and to the organization.

Words matter. In the past, Gladwell has been accused of cherry-picking and oversimplifying evidence, and the “universal law” of the “Magic Third” is more of the same. If there is a “universal law” and if it involves a “Magic Third”, Gladwell hasn’t proven it. Representation within groups is important, but reducing that complexity to a marketable catchphrase does a disservice to the readers Gladwell claims to be writing for, and to the researchers whose work has produced much more valid and useful insights on the issue.