That Very Depressing 4.74 Degrees of Separation
David Berreby is the author of "Us and Them: The Science of Identity." He has written about human behavior and other science topics for The New Yorker, The New York Times Magazine, Slate, Smithsonian, The New Republic, Nature, Discover, Vogue and many other publications. He has been a Visiting Scholar at the University of Paris, a Science Writing Fellow at the Marine Biological Laboratory, a resident at Yaddo, and in 2006 was awarded the Erving Goffman Award for Outstanding Scholarship for the first edition of "Us and Them." David can be found on Twitter at @davidberreby and reached by email at david [at] davidberreby [dot] com.
Have you ever poked around in the "People You May Know" box in Facebook? For the first few score people, it's a pleasure. Click: A person I forgot I knew. Click. I always wondered what happened to her. Click. Wow, seven mutual friends with this famous person! Click. Click. Click. It's fun until you realize that when you hit "See More," the list always auto-refreshes, and you will never, ever come to the end of People You May Know. This study, about which Facebook's research team posted last night, points to one reason: Though "everyone knows" that no two people are more than six degrees of separation from one another, in fact Facebook's 721 million users, with their 69 billion "friend" links, are actually closer than that. The researchers found the average number of links from one randomly picked Facebooker to another is 4.74. Within any single nation, most pairs of people are separated by only three degrees.
So does this mean we are all one happy world, and we should break out the guitars and starting singing "Kumbaya"? Not really. Though it's true that "even the most distant Facebook user in the Siberian tundra or the Peruvian rainforest, a friend of your friend probably knows a friend of their friend," as the Facebook post put it, Lars Backstrom and his co-authors also found that most people's connections are quite parochial. Yes, your friends may be linked to one friend of theirs who is linked to that guy in Siberia, but if you're typical, 84 percent of your Facebook friends are in your own nation, the researchers say. Also, your Facebook friends are likely to be overwhelmingly close to you in age, and you're likely to have the same number of friends as your neighbors. Facebook, as the post says, "connects people who are far apart, but also has the dense local structure we see in small communities."
It's the People You May Know section, I think, that reveals the vast difference between the "small community" aspect of Facebook and the "far-apart" side. People I've chosen for Facebook friends mean something to me (though, as John Markoff and Somini Sengupta pointed out today, the definition of "friend" varies, in real life and in the Facebook universe, in ways that affect this kind of study). On the other hand, People I May Know are statistical accidents. They're strangers who happen to have a tie to someone who has a tie to someone whom I might care about. And there are so damn many of them.
You think you see the end of this parade—the scroll-down lozenge at the bottom, that's a wrap!—but no, it refreshes. It always refreshes, so there are always more People You May Know, stretching on and on in their billions. After a while, fun fades and in comes exhaustion—so many people, so many kids and pets and vacations and hobbies. So much human effort and feeling that's important to someone but meaningless to me. Zip through these weakly tied profiles, and social life, the point of Facebook, comes to meaningless.
How interchangeable we are, after all, as we so individually and idiosyncratically pursue, and fear, and celebrate, the exact same things. So many kids, pets, vacations, hobbies, favorite quotes, great meals and lousy weekends. On and on it rolls, click, click, click, like the parade of future kings in Macbeth. Another 200 people I may know? Am I really tied to the whole human race?
I wonder if serial killers think this way—they're all alike, each so caught up in their own importance, to themselves and a few score others, what difference does the loss of one or two of these make? And I can't help feeling, somehow, that this wasn't Facebook's intention.
Facebook wants us to enjoy being connected, and feeling that more connections are easy to make. But seeing so many people who are at once nobody to me and somebody to themselves has the opposite effect. I imagine my own profile in the indifferent eye of that guy in Siberia who knows that guy in Tashkent who is friends with an old college chum. I'm nobody special to him, and from his perspective, he's right. The zone where I am somebody special is so small, and so unremarkable, and so brief. What's the use of all this connecting, then? "People You May Know" ends up being a reminder that I'm not that connected after all, and that there are degrees of separation Facebook can never cure.