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When 6 Becomes 4.74...Among Friends

You are probably aware of the phrase "six degrees of separation." It has been touted as a measure of the average number of acquaintances separating any two people in the world.

Recent research involving 721 million Facebook users (about 1/10 of the world population) has reduced this claim now to "4.74 degrees of separation."

The actual chain of events underlying this phenomenon is fascinating:

  • In 1929, Hungarian author Frigyes Karinthy wrote the short story Chains (no English translation), which first proposed the "six degress of freedom" idea.
  • In 1967, psychologist Stanley Milgram published the paper The Small World Problem, using research to document Karinthy's claim.
  • In 1990, playwright John Guare wrote the play Six Degrees of Separation, which explored Milgram's claim.
  • Guare's play and Milgram's research led to the parlor game Six Degrees of Kevin Bacon, which links Hollywood folk.
  • And in 2011, Facebook researchers have revised this claim to 4.74 degrees of separation.
One wonders what the next step in this story will be... Will technology eventually reduce the number 4.74 significantly? A scarey yet somewhat attractive idea.

If only Gottfried Leibniz was alive today...he would be facebooking, twittering, blogging, etc.! If you do not understand why, you might do some background reading on Leibniz's life and his social motivations. A good start is Robert Minto's blog Bifurcated Life.

Source: J. Markoff and S. Sengupta's "Separating You and Me? 4.74 Degrees," NYT, 11/22/2011