So, i ran into a guy at the supermarket who's cousin was your brother's barber back in Piscataway. Small world, huh?
No. No, it's not.
In fact, it's a rather large world filled with 7 billion people, most of which are clustered in fairly distinct areas yet surprisingly connected thanks to commerce and modern communications nets. In fact, it's been proven that, thanks to math, damn near everyone is interconnected with everyone else with a surprisingly small number of steps. (No matter who you are, i'm probably associated to you by 6 steps. Well, unless your Kevin Bacon. i think he's, like, 10 steps out because of constant effort on his part.)
The problem is that if you were to interact with someone to whom your network had zero interactions with, you'd have absolutely no way of knowing. Well, i'm wrong, you could interview the individual for hours comparing the lives of these individuals against the associations you've cataloged for years to ensure that there was no match, but that might take a bit longer than the elevator ride. Granted, this might be made easier in the future by simply cross indexing the collection of restraining orders.
Honestly, it'd be far more interesting to discover the tiny percentage of individuals on the planet to whom you truly have zero points of interaction with. i have no idea what you'd talk about, or what language you'd use to do so, but at least you could rest assured that you've destroyed that level of disconnect forever ensuring that future generations will again pass each other with awkward silences and uncomfortable glances.
And isn't that really what civilization is all about?