The idea that any two people on Earth are separated by only a few social connections is known as the "six degrees of separation" theory. This concept, deeply rooted in popular culture, has a solid scientific foundation and a long history of research. Its foundation was laid not by sociologists, but by the Hungarian writer Frigyes Karinthy, who in his 1929 story "The Links of the Chain" proposed that any two people on the planet are connected by a chain of no more than five intermediaries. This artistic hypothesis later inspired scientists to conduct large-scale experiments. Stanley Milgram's Experiment: A Small World in Envelopes In 1967, the first empirical test of the theory was conducted by the American psychologist Stanley Milgram. In his famous experiment, residents of the American city of Omaha were randomly sent letters asking them to forward them to a specific stockbroker in Boston. The sender could only pass the envelope through their personal acquaintances, who they believed could be "closer" to the target. Only a small number of letters reached the final addressee, but the key result was the average number of transfers — it was about five to six. This experience gave rise to the now-famous phrase "six degrees of separation," although Milgram's methodology has been criticized repeatedly for potential statistical errors and lack of representativeness. The Evolution of the Theory in the Digital Age With the advent of the internet and social networks, scientists had an unprecedented opportunity to test the hypothesis on vast amounts of real data. Researchers from Microsoft in 2008, analyzing over 250 billion instant messages sent between 240 million users, found that the average distance between any two users of their service was 6.6 steps. A similar study conducted on Facebook data showed even closer connections: in 2016, the average distance between users was only 3.57 steps. These numbers demonstrate that digital platforms, acting as a global social cataly ... Read more