How Many Friends

How many friends can you have? According to Dunbar’s number, the magic number is 150. Oxford University anthropologist Robin Dunbar says 150 is the most the brain can absorb. People within that circle had a personal relationship based on history and shared experience. He explains his reasoning in the book How Many Friends Does One Person Need? The first five are people you’d go to prison for. You wouldn’t do it for most of the next 10 but you would loan them $100. You’re less emotionally engaged with them. You might lend $20 to those in the next layer out, taking you to 50 people. The final 100 are folks you might do a favor for. Some researchers are using Dunbar’s number to determine how much storage is needed for mobile phone address books. Others are using it as a guide toward building the optimum organizational structure.

Stephen Goforth