Friends of friends: how the theory of six handshakes works (5 photos)

We all know each other. Not directly, but through mutual friends.





US psychologists Stanley Milgram and Jeffrey Travers back in 1969 put forward an interesting theory: every inhabitant of the planet knows others through a chain of mutual acquaintances. On average, the length of the chain does not exceed 6 people.

Attempt to prove



Researchers proved the hypothesis about the connectedness of social networks using the following experiment: they distributed 300 envelopes to residents of one city. They should have been transferred to the addressee in a neighboring city. But with a mandatory condition - to act only through friends. As a result, 60 of them reached a specific Bostonian in this way.

During the transfer process, each subsequent person in the chain had to make a note about who he was passing the envelope to next. As a result, psychologists found that the length of the chain averaged 5-6 people. And the result surprised Milgram and Travers, because initially they assumed that the chain would stretch for a whole hundred, or even more.

The Six Handshakes Theory Today





Attempts to confirm the hypothesis have been made repeatedly. And the results turned out to be approximately the same. In 2012, sociologists at Columbia University made the task more difficult. The experiment involved thousands of volunteers who had to find classified objects. Only the basic minimum was given about them: full name, education, occupation, place of residence. During the test, the Australian was the first to manage to find the addressee from... Siberia! Using a chain of only four people.



Microsoft experts spent two years studying messages that users provided access to. As a result of data analysis, it was found that each of the 240 million user audience could find a given user in an average of 6.5 steps.



Have you ever seen the theory of six handshakes in action?