IF YOU get unexpected e-mail from an American university over the coming
months, don’t just assume it’s junk. It could be from scientists investigating a
fascinating social phenomenon.
According to urban folklore, everyone in the world knows everyone else via
just a few intermediaries—an effect summed up by the phrase “six degrees
of separation”. The number six emerged from an experiment performed in 1967 by
the social psychologist Stanley Milgram, who sent packages to several hundred
randomly selected people in America’s Midwest, with the aim of getting them
delivered to target people in Boston.
Each recipient was given some…
