Dunbar’s number

Dunbar’s number

Judging from human brain size and complexity, Dunbar calculates that a person’s social group should incorporate about 150 people—this is the maximum number of relationships our brain can keep track of at one time. This figure, now graced with the name “Dunbar’s number” takes different types of relationships into account. On one end of the spectrum, we have a core group of about five people we talk to once a week. On the other end, we have a group of around 100 acquaintances to whom we speak about once a year.