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Dec 20, 2022·edited Dec 20, 2022

Ok, relevant topic: In my experience the 150 number sort of holds up. Perhaps it’s somewhat lower. Maybe 100 or so. But it may vary depending on domain.

The post caused me to re-think what has been a mystery of my work experience: Without going into too much detail, I had a job where I was effective for a period of time, and then suddenly found myself bogged down in politics. I frequently complained that I was spending more time negotiating deals with my internal colleagues than with external counterparties. The group and company were growing tremendously, and this effect probably occurred somewhere around the 100-200 mark. As it turns out, I abandoned the team to go work on a new initiative, made up of about 30 people. That group too quickly grew to about 2000 and became completely unwieldy, ultimately leading to its failure. (This was at a company that likes to think of itself as “the world’s biggest startup”, which really just means that it pays very little attention to developing an effective bureaucracy.)

Amazon famously (apocraphally?) has it’s “no meeting with more people than can be fed by one pizza” rule. That would suggest another rule perhaps around 10 people or so. That rule seems to correlate to my experience as well, and to sports teams generally (11 is a common number for team sports with large organized groups).

I wonder how much these numbers correlate to the size of various divisions in military organizations. And I wonder whether the size of those organizations changes during wartime, when you’d think coordination problems would be different and high-stakes than in peace time?

For me, I wonder now, how many workplace issues that one would tend to attribute to “personality differences” are effectively attributable to organizational structure, and indeed, attributable to a simple variable like average group size.

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Charles Perrow has a whole book 'Complex Organisations' which talks about organisational structure this way. https://www.goodreads.com/book/show/843371.Complex_Organizations

Well worth a read if this is the sort of thing that interests you. And the book is extremely readable, not turgid academic prose.

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Thanks. Ordered!

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From the military side, the US Marines have a rule of three structure, where every rank is in charge of three sub-rank groups. So 3 privates led by a corporal, three corporals are under a sergeant, three sergeants under a lieutenant, etc. That limits the immediate reports to three people, and 12 if you consider those three people's three reports. That strikes me as being very close to the 9-11 people on a sports team number, and pretty close to the general number of folks you can get into a single meeting and have them be relevant to the discussion (and paying attention.)

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"Amazon famously (apocraphally?) has it’s “no meeting with more people than can be fed by one pizza” rule. That would suggest another rule perhaps around 10 people or so. "

Not quite correct. The idea is that each team should be able to be fed by 2 pizzas (so 6-10 people) and that a single team should own the full service from end-to-end. So "two-pizza team" is the Amazon term.

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Ha! Well, I guess it depends somewhat on how much people like pizza and how big your pizza is! But two pizzas it is.

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founding

Informal social control is a crucial private-governance mechanism in groups and orgs of any size, insofar as networks form, norms emerge, gossip circulates, and individuals care about reputation and its consequences.

Student-athletes tell me that sports teams have a bedrock norm in dispute-resolution: "It never turns out well when coach gets involved." Accordingly, they live by informal social control, in which captains play a focal role.

Good managers expect subordinates "to work it out" in day-to-day frictions. Employees have contempt for colleagues who go straight to the top in dispute-resolution.

Cop shows always showcase informal social control in the force, as well as mistrust of complex organization (esp. 'encroachment' by other branches of the force, and 'internal affairs' sub-orgs).

Good CEOs worry about boundaries of the firm (what to outsource), incentives (principal-agent problems) *and* firm culture.

The Dunbar number plays a substantial role in super-Dunbar orgs, via emergent informal social control.

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Military organizations tend to bear this out.

Infantry squads almost always gravitate to be in the range of 10 men, and if they are larger they are usually formally subdivided into 3 or 4 man teams. Span of control is almost always 3-4 direct reports at most levels, with commanders advised to also think one level down, which again produces a number of direct contacts in the range of 10 to at most 20.

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Strikes me as an important concept for social media and content moderation. Sub-Dunbar informal norms and the spirit of the law for me and my friends and super-Dunbar formal bureaucratic structure and the letter of the law for my enemies.

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author

I don't think it's as straightforward as that, but I do think that smart phones do confound the Dunbar number. You treat people you don't really know as if they were involved in your life, and you see people within your circle as if they were on stage.

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It is funny, I have been thinking about this a lot lately. I started a new job that subs out all work that does involve sitting in front of the computer. Everyone is at least a “Director”, except for a few office staff. There are a few very large subcontractors, but most are below 150. We and the contractors are much further along in specialization as well. It seems to work very well.

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I'm increasingly thinking about avg, below avg, and above avg IQ. In Trust, in mobility, in jobs, in relations.

It seems likely to me that the Dunbar number will be lower or higher with IQ.

It seems likely that the number of folk one trusts is below the Dunbar number, and not so related to IQ -- many untrustworthy folk are high IQ folk. Libertarians I've met often included folk who were willing and able to scam others, more than Christian church goers of lesser intellect.

Gaining new friends, real friends you both socialize with AND can easily ask for help, takes time and energy - it's usually easier to maintain them then to gain them. A church or club "community" often is larger than the Dunbar number, but your good friends within that larger group make up a smaller than Dunbar number sub-group.

One amazing thing about Homo Sapiens is the possibility of getting hundreds together without them fighting - those who study chimps or other primates would agree it's not possible with other such primates. Thinking about human interdependence leads to lots of interesting thoughts.

Plus it distracts from learning how corrupt, treasonous, the FBI was acting thru 2020 (under Barr DOJ & Wray FBI) to protect Biden by censoring the truth about his laptop - censorship truth we're only learning about in detail because of Must. Big group cooperation depends on trust, and the FBI doesn't deserve any Republican's trust.

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Don't suppose Allen Curves would be next?

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When starting a small business it is possible to grow to almost the Dunbar size before changing top management. I knew that I could only manage a small size (<50) within my skill set.

My friend managed to grow his company to 500 employees before he sold out to a multi-billion dollar company. He managed to keep some of the small business culture and knew the name and family details of all 500 employees.

I hadn't heard about the Dunbar number (thanks), but we had spend many conversations discussing the size for fundamental management style change and change in focus. At what point does having a common goal for the whole organization shift.

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I worked for an independent company that had about 200 employees (not counting a remote location that was focused on software development and services and which department was eventually sold). I knew almost everyone by name, and the others at least by face. It was, for me, a great place to work. Alas, the company was sold to a larger organization, which grew this subsidiary five-fold, and changed the culture from a "partnership" to a "hierarchy." Not saying it was a good or bad change, just a clear change in approach.

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founding

Wonder if you can adapt the Dunbar number to child development and optimal class size, i. e., smaller classes for elementary schools, progressively larger for middle school, high school, then college.

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The Kerala snake boat race may be an example of a sport where teams exceed Dunbar's number, especially if you include the non-rowers who provide other support as 'on the team'. see: https://en.wikipedia.org/wiki/Vallam_kali

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author

1. To me, sports involve defense. So I would not even count golf.

2. If most people around the world have not heard of it, I don't think it counts as a *major* sport.

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"To me, sports involve defense. "

I do not understand how one reaches that conclusion.

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Is Chess a sport? Maybe that’s another topic... And for another other topic: Since we’re discussing what counts as a “sport”, I was wondering the other day if there is any team sport that doesn’t use a ball. Ice Hockey maybe, but a puck is sort of ball-like. Ultimate Frisbee. Curling. Crew would not count, based on your “defense” criteria. (I will add a relevant post, to make amends for running off topic.)

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Kabbadi, team MMA, synchronised swimming, motor racing (whole support crews, multiple drivers), pro cycling - domestiques are really put upon, adventure racing, rowing, sailing....

A few odd combat sports and mostly "racing" sports with bigger and more complex vehicles.

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I think counting crews is sort of cheating. I should have added one more caveat to the thought experiment: no sports where it's possible to do alone. So Team Rhythmic Gymnastics doesn't count, because there's a solo version. (Plus, there's a ball... sometimes!)

But synchronized swimming is a good one – without two people it would be silly.

Racing sports are interesting – I wonder if Kling would count those as sports. Many have some sort of defense, although not as obvious? What about track and field – probably not?

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Yet "in the boat rowing" is sub-Dunbar:

"The race of chundan vallam ('snake boat', about 30-35 meter (100-120 feet) long with 64 or 128 paddlers aboard[1]) is the major event and a major tourist attraction"

Cool idea to create tourism thru a mostly fun big-team sport. Thanks for link - but it doesn't show a team > 150.

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