Are you familiar with the “six degrees of separation” theory? It has fascinated me for years, ever since I saw John Guare’s play of that name in London back in the 1990s. The title comes from the theory that any two people on the planet are connected by a chain of six acquaintances. In other words, you, the stranger reading this article, are connected to me by an average of six people: I know X, who is a friend of Y, who in turn is a friend of L, who is a friend of yours, that would make four degrees of separation between us.

What struck me about this theory is that while in the West it was a theory, in the Arab world it is a reality. Just watch two Arabs meeting for the first time. What do they do? They find the acquaintances that connect them: “Ah, you are a Kurdi? I went to school with someone named Kurdi...” and they will keep at it until they have identified the people they have in common in their social network. It is part of a way of life where people need to know who you are socially and place people in a clearly drawn social map. Not only does it mean you know who you are dealing with, but it facilitates social exchange in a world where personal connections create trust.

The reason I know this theory to be reality is that my family comes from Madinah, and in Madinah people are so proud of the connections that link families to each other that the first thing people do when they meet is establish not who they know in common but how they are related to each other — and they always are! And generally, the chain that links them is no longer than five or six degrees of separation. So last month when my uncle met one of my best friends in London, he established for us just how we were related. Her mother is from Madinah and my father is from Madinah, her mother and my father — it turned out — have the same great-grandmother. To be fair, we already knew we were related in some way, but it had been an assumption, whereas my uncle drew it out on a napkin for us, drawing both family trees until they met.

On the other hand, here in Europe I find I can be close friends with people, know them for years and yet not know their family name. We are introduced by our first names and it feels strangely old-fashioned and formal these days to present yourself otherwise. When you exchange contact details, these are generally e-mail and phone number. Just last week I found myself outside an apartment block in Cannes looking at a list of names on the bells, wondering which one might be the family name of the friends who had invited me to dinner. In the end I had to phone them and ask.

In Britain, even that is not necessary as apartments go by letter or number. You can easily only know someone as “Jo” who lives at No. 10 Avenue Road and does something in finance. You do not know someone’s family background? The very idea is so alien to my Arab upbringing.

Essentially it is a more individualistic way of looking at people. If I am friends with Jo it is because I like Jo’s personality or because we have interests in common. Friendship is built on shared experience, rather than on shared social membership. Of course that is true with all friendships, the only difference being in the extent and closeness of the social networks in which we live. Some people need to feel they are part of a closely-knit community; others like the freedom of imagining themselves an island.

And so I find it amazing that any two people on this planet can be linked by six degrees of separation. It’s a cute theory. That it applies to close-knit communities like Saudi Arabia, I find entirely unsurprising. But can it really be the case that it applies everywhere?

Over the years, several researchers have tried to test the theory, with limited success. But now, courtesy of Microsoft, we know it to be true. Two researchers at Microsoft analyzed a database of 30 billion electronic conversations in June 2006 of people connected to their instant messaging network. That’s 180 million people scattered around the world and exchanging messages on the Internet. What they found was that if you picked any two people at random, the chain that linked them consisted of an average of 6.6 people. In other words, they found that for any two users of Microsoft IM, you could link them together through a chain of people they had exchanged messages with. The average length of this chain was 6.6 and the longest 29. Some 78 percent of people could be connected to each other in less than seven steps. So it’s a small world after all! Of course owning a computer and using IM already limits the relevance of the sample, but still! And just think, in today’s world you can be friends with people you have never met, people who live hundreds of miles away and lead lives entirely different to yours, but with whom you have daily interaction because you share an interest in football, or politics, or origami... That’s the beauty of the Internet. It makes six degrees of separation a reality.