In the latest Seed, there’s an interesting dialogue between political scientist James Fowler and physicist Albert-Laszlo Barabasi. I was particularly intrigued by their ruminations on the network dynamics of Facebook:
JF: When we move from five friends in real life to 500 on Facebook, it’s not the case that we are having a close, deep relationship with each of those 500 friends. In fact, one of the intriguing things I’ve noticed about these online networks is that they have a property that’s different from realworld social networks. As you know, in the real world, popular people tend to be friends with popular people. But in these technological networks, as in metabolic networks, it’s just the opposite. The nodes with many, many links will tend to be linked to nodes with few links.
JF: It makes me wonder if the dynamics of online social networks are going to be reflective of realworld social networks. Because to a large extent, in your work and some of the work that I’ve done, we’re relying on the idea that what we see online is telling us something about the real world. But there’s a pretty fundamental difference.
I’m not on Facebook, so take what follows with a hefty pinch of salt, but there’s some suggestive evidence that the brain might contemplate other people very differently when that person is a virtual Facebook “page” and not a flesh and blood individual, with a tangible physical presence. Humans, after all, are social primates, blessed and burdened with a set of paleolithic social instincts. We aren’t used to thinking about people as computerized abstractions.
Consider this elegant experiment, led by neuroscientist Joshua Greene of Harvard. Greene asked his subjects a series of questions involving a runaway trolley, an oversized man and five maintenance workers. (It might sound like a strange setup, but it’s actually based on a well-known philosophical thought puzzle.) The first scenario goes like this:
You are the driver of a runaway trolley. The brakes have failed. The trolley is approaching a fork in the track at top speed. If you do nothing, the train will stay left, where it will run over five maintenance workers who are fixing the track. All five workers will die. However, if you steer the train right⎯this involves flicking a switch and turning the wheel⎯you will swerve onto a track where there is one maintenance worker. What do you do? Are you willing to intervene and change the path of the trolley?
In this hypothetical case, about ninety five percent of people agree that it is morally permissible to turn the trolley. The decision is just simple arithmetic: it’s better to kill fewer people. Some moral philosophers even argue that it is immoral to not turn the trolley, since such passivity leads to the death of four extra people. But what about this scenario:
You are standing on a footbridge over the trolley track. You see a trolley racing out of control, speeding towards five workmen who are fixing the track. All five men will die unless the trolley can be stopped. Standing next to you on the footbridge is a very large man. He is leaning over the railing, watching the trolley hurtle towards the men. If you sneak up on the man and give him a little push, he will fall over the railing and into the path of the trolley. Because he is so big, he will stop the trolley from killing the maintenance workers Do you push the man off the footbridge? Or do you allow five men to die?
The brute facts, of course, remain the same: one man must die in order for five men to live. And yet, almost nobody is willing to actively throw another person onto the train tracks. Greene argues that pushing the man feels wrong because the killing is direct: We are using our body to hurt his body. He calls it a personal moral situation, since it directly involves another person. In contrast, when we just have to turn the trolley onto a different track, we aren’t directly hurting somebody else. We are just shifting the trolley wheel: the ensuing death seems indirect. In this case, we are making an impersonal moral decision.
What makes this thought experiment so interesting is that the fuzzy moral distinction⎯the difference between personal and impersonal decisions⎯is built into our brain. When the subjects were asked whether or not they should turn the trolley, a network of brain regions assessed the various alternatives, sent their verdict onwards to the prefrontal cortex, and the person chose the clearly superior option. Their brain quickly realized that it was better to kill one man than five men.
However, when people were asked whether they would be willing to push a man onto the tracks, a separate network of brain areas was activated. These folds of gray matter⎯the superior temporal sulcus, posterior cingulate and medial frontal gyrus⎯are believed to be responsible for interpreting the thoughts and feelings of other people. As a result, these subjects automatically imagined how the poor man would feel as he plunged to his death on the train tracks below. They vividly simulated his mind, and concluded that pushing him was a capital crime, even if it saved the lives of five other men. Pushing a man off a bridge just felt wrong.
What does this have to do with Facebook? I think it demonstrates how thinking about a person in physical terms – as someone we need to physically push – changes how the brain represents that person. When the person is a virtual abstraction, an impersonal representation on a computer screen, the brain treats them accordingly, and seems to invest them with less agency, emotion, etc. Perhaps – and this is a big perhaps, since nobody has done the scanning experiment – we make social decisions concerning many of our Facebook acquaintances using these “impersonal” brain areas. In other words, we might push a Facebook friend off a footbridge, but we’d never push a real friend.
I don’t mean to criticize Facebook. I simply agree with Fowler: Facebook is a new experiment in human social interaction, and we shouldn’t be surprised that the network dynamics of Facebook don’t resemble the network dynamics of the real world, whatever that is.