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Scope Series 4 RTÉ Two, Thursday, 7.00pm

Six Degrees of Separation

Kevin BaconSix degrees of separation is the concept that every single person is connected to any other random person on Earth through a chain of no more than five people.

You may yourself have even played a game based on the theory, called Six Degrees of Kevin Bacon. One person chooses an actor which another has to link to Hollywood actor Kevin Bacon in six movies or less.

In 1967, American social psychologist Stanley Milgram put the hypothesis, which he called the 'the small-world problem' to the test. He chose two targets, one in Massachusetts and another in the American Midwest. He then had randomly selected people from across the U.S. try to get postcards to the targets without giving them an address.

Senders knew only the intended recipient's name, occupation and general location. They then had to send the card to someone they knew on a first name basis and reckoned most likely to know the target, and so on, until the letter was delivered.

Tobias ThelierParticipants expected the chain to include at least a hundred intermediaries but 80% of the letters that made it through were delivered in four or fewer steps. Almost all were delivered in less than six. Milgram published his findings in Psychology Today.

The theory made the leap from academia to popular culture when playwright John Guare chose ‘Six Degrees of Separation‘ as the title for his 1990 play. That play went on to become a movie by the same name starring American actor Will Smith.

In 2001, Columbia University Professor Duncan Watts updated Milgram’s experiment for the modern era. He had 48,000 people forward an email to one of 19 targets in 157 countries. Indeed, Watts found the magic number was six.

Watt's work has opened up questions as to whether the six degrees of separation hypothesis can be applied to such diverse areas of research as disease transmission, corporate communication, power grid analysis and even computer circuitry.

In this episode, University College Dublin political sociologist Tobias Theiler delves the issues surrounding the six degrees hypothesis.

He asserts technology has given us a whole new concept of what it means to know another person. Communication has gotten better and cheaper, crashing conventional barriers between people.

Anyone might be just one Google search away.

Online chat rooms and social networking sites like Bebo and MySpace make it possible to have hundreds – or thousands – of “friends” without ever having met them face-to-face.

SCOPE is creating our own Irish six degrees experiment. We’ll choose a random target and group of senders and find out how many people it takes to connect them.

Our completely unscientific hunch is it will take fewer than six steps. Ireland has only a few major urban centres – Dublin alone houses one-fourth the national population – and most Irish people, even if they move away from home, maintain strong regional and family ties.

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