What is the theory of six degrees of separation, and what connection does it have to actor Kevin Bacon?

Have you never heard that the world is all interconnected, and that we always have a friend who is a friend of a friend of another friend? The theory of six degrees of separation addresses this: it is the idea that any person in the world can be linked to another through a chain of acquaintances with, at most, six intermediate connections. More simply, according to this theory, any individual is just six people away from another individual.

The theory has existed since the 1920s – it was stated in the work Chainsby the Hungarian Frigyes Karinthy -, but it was formalized in the 1960s by the psychologist Stanley Milgram, who led an experiment called the “six degrees of separation experiment” or “small world” (The Small World Problem, originally).

In this investigation, the expert asked 296 volunteers from the USA to write and send postcards to a specific person in Massachusetts, only through acquaintances. The result showed that, on average, it only took about six calls for the letter to reach the intended recipient.

Later, this theory was revised by researchers, in a study carried out by the social network Facebook. Using algorithms prepared by a team from the University of Milan and based on the interconnections between more than 700 million Facebook users, it was concluded, after a month-long experiment, that the six degrees dropped to 4.74.

“We are all close, in a certain way, to people who don’t like us, who don’t sympathize with us and who have nothing in common with us”, he said, in 2011, in an interview with The New York TimesJon Kleinberg, professor of computer science at Cornell University, adding that “it is weak ties that make the world small.”

Inspired by this theory, which aims to demonstrate that the world is even more interconnected than we think and that, even with great social or geographic distances, there is always a small number of connections that can connect us to any other person, it has existed since the 90s , the iconic game Six Degrees of Kevin Baconwhich aims to connect any Hollywood actor to Kevin Bacon in six steps or less, through the films they starred in together.

The game emerged as a joke among film students at Albright University, in Pennsylvania, USA, after they observed that Kevin Bacon had appeared in a large number of films with several colleagues, and became known after the release of an article in the French magazine Premiere , in 1994, which mentioned the ability to connect any actor to American actor Kevin Bacon in six steps or less.

The game gained so much popularity that an official website was even created, the The Oracle of Baconwhere players can enter any actor’s name to find out what their connection to Kevin Bacon is, to six degrees or less.

Kevin Bacon himself “embraced” this concept, even creating the non-profit organization SixDegrees.org.