Six Degrees of Urban Myth

Everyone is connected by six degrees of separation.

I like the sound of that. The phrase it's a small world after all has been seared into my mind by singing robots at Disneyland. (Do you have that song stuck in your head now? Sorry.)

Six Degrees became a popular phrase after a play from John Guare called "Six Degrees of Separation" became a hit, but the idea has been floating around since 1967, when a social psychologist named Stanley Milgram wrote it up in the first issue of Psychology Today:

"Fred Jones of Peoria, sitting in a sidewalk cafe in Tunisia, and needing a light for his cigarette, asks the man at the next table for a match. They fall into conversation; the stranger is an Englishman who, it turns out, spent several months in Detroit. 'I know it's a foolish question; says Jones, 'but do you by any chance know a fellow named Ben Arkadian? He's an old friend of mine, manages a chain of supermarkets in Detroit...'"

Milgram never used the phrase six degrees of separation, but he believed his research proved that anyone in the United States was connected to everyone else by about 5.5 personal links. Kevin Bacon, an actor often believed to be connected to all other actors by six degrees, liked the idea and started a foundation to connect people to worthy causes.

"You've probably heard of the Six Degrees concept. Any one person (including me, Kevin Bacon) is connected to any other person through six or fewer relationships, because it's a small world." -www.sixdegrees.org

Milgram did his experiment using the US Postal Service. He mailed folders to people he called "starters" and asked them to help him get the folder to a target person in a distant city. They would do this by mailing the folder to someone they knew who might in turn know the target person. Milgram reported that it took six jumps to get the folder to the right person. Amazing!

Amazing that is, until subsequent researchers like Judith Kleinfeld checked Milgram's original notes and discovered that some of his other studies didn't go so well.

Very few of his folders reached their targets. In his first, unpublished study, only three of 60 letters--5 percent--made it. - Psychology Today

That hasn't stopped Six Degrees. Malcolm Gladwell wrote an essay called Six Degrees of Lois Weisberg. Yahoo! scientist Duncan Watts is also working on Six Degrees with computer models. Watts did a version of the Milgrim experiments using emails instead of letters. As Fast Company reported, Watts used a Web site to recruit 61,000 people, then asked them to ferry messages to 18 targets worldwide. It took six links to get the message to the target. That would seem to validate Milgram's work, but not all researchers are convinced.

There is a powerful network linking us all, and maybe Milgram had the right idea - even though his research was flawed. I hope he did get the idea right - because eight degrees from Kevin Bacon just doesn't sound as good.

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