The Rule of 150

I picked up the book "Blink" by Malcolm Gladwell 2 weeks ago and found it to be a very entertaining and quick read. So, I followed up last week and bought his earlier book, "The Tipping Point." Gladwell writes for the New Yorker and that magazine style of writing comes through in the book, making each chapter a very engaging tale of its own.

There is actually so much engaging info in these books that it's hard to absorb it all. It's very entertaining to read, but it goes so quickly that I need to review in order to actually internalize the info. So, I'm going to try writing about it, bit by bit, and see if I can remember various topics better as I go along. I left "Blink" at home this week, so today's post is from "The Tipping Point."

In one chapter, he talks about social behavior in humans and primates. It turns out that there is evidence to indicate that the main driver for our large brain size (and intelligence) is social relationships. Look at primate community behavior, there is a pretty consistent relationship between social group size and brain size. This has some interesting ramifications for modern human social interactions because if you look at the group size/brain size curve for primates and extrapolate the relationship to humans, the group size you get for our brain size is 150 people.

The hypothesis here is that as a function of our evolution, our brains are wired to effectively manage social relationships that include up to about 150 people. Gladwell then investigates this 150 person number in modern communities and social structures (e.g. companies) and finds that this "magic number" comes up often. In one example, he looks at the W. L. Gore corporation, makers of Gore-Tex and other high-tech products. Their company is designed around the rule of 150. The story is that during the growth of the company, they found that the largest effective size of a slice of the business (e.g. marketing, manufacturing, sales all rolled together for a given product or segment) was around 150. So, they organized their company around this principle, having buildings designed to house exactly 150 people and organizing the business into self-contained 150-person units. They find that there is remarkable alignment and performance in their business when the manufacturing people and the sales people are wrapped together in the same social unit.