Robin Dunbar, an anthropologist, says you can comfortably maintain close relationships with 150 people. Our brain seems to be too small to allow for more.

This would explain why people seem to ‘lock themselves up’ in small groups, with a limited group identity. Circa 150 people who are in actual physical proximity find a common theme to organize themselves around, and beyond that theme or those themes, nothing seems to exist anymore, and new members are only sporadically absorbed, those who aren’t members are often quickly seen as the enemy.

This also explains why the military units in which the members know each other personally are about 150 strong. Look at a company in a regiment that’s part of a brigade, which is part of a division. You can feel the spirit of that division, the brigade can have a reputation, the regiment can be known for certain actions, but who will you interact with face to face? The people in your company, a unit that is about 100 men and/or women strong.

This could also explain why we are all so averse to getting to know, to invest in, strangers. If you only have a maximum of 150 ‘slots’ to fill, it’s no wonder you become picky. Especially as one grows older and has had one’s fair share of betrayals, back stabs and general careless behavior.

I have tried to put my ‘tribe’ in a Facebook list and I couldn’t find 150 people to put on there. I even had to cheat a bit and include some people I feel theoretically close to, but haven’t seen in years…

My brother, one of the most sociable guys I know, surprised me last week by saying: ‘You know, in the end, there seem to be only about 7 people you can actually count on.’

This statement didn’t just drop out of thin air. He was moving house, so that’s one of those times you discover how many people are actually willing to lift a finger to help you along.

Dunbar himself categorizes those 150 people thus:

“the number of people you would not feel embarrassed about joining uninvited for a drink if you happened to bump into them in a bar”.

150 out of more than 6 billion…

No wonder the world often seems like such a hostile, uninviting place, filled with zombies who pass us by as though we are invisible.

I also think that at present our economic situation is so volatile, so ‘liquid’ (a term borrowed from the late Zygmunt Bauman) that many people are struggling to maintain comfortable connections to even as low a figure as 150, I think it’s far less, because we’ve become so mobile, because social networks give us the illusion of being connected, without really investing anything into that connection, because we change jobs more often than ever before, and because more and more seem to be always on the move, swapping people for whomever happens to me the most useful at that moment in their life…

If am being too pessimistic about our species leave your thoughts in the comments below.