On Easter Sunday, a man in Cleveland filmed himself murdering a random 74-year-old and posted the video on Facebook. The social network took the grisly clip down within two or three hours, but not before users shared it on other websites — where people around the world can still view it.

Surely incidents like this aren’t what Mark Zuckerberg had in mind. In 2012, as his company was preparing to go public, the Facebook founder wrote an earnest letter to would-be shareholders explaining that his company was more than just a business. It was pursuing a “social mission” to make the world a better place by encouraging self-expression and conversation. “People sharing more,” the young entrepreneur wrote, “creates a more open culture and leads to a better understanding of the lives and perspectives of others.”


Earlier this year, Zuckerberg penned another public letter, expressing even grander ambitions. Facebook, he announced, is expanding its mission from “connecting friends and family” to building “a global community that works for everyone.” The ultimate goal is to turn the already vast social network into a sort of supranational state “spanning cultures, nations and regions.”

But the murder in Cleveland, and any similar incidents that inevitably follow, reveal the hollowness of Silicon Valley’s promise that digital networks would bring us together in a more harmonious world.

Whether he knows it or not, Zuckerberg is part of a long tradition in Western thought. Ever since the building of the telegraph system in the 19th century, people have believed that advances in communication technology would promote social harmony. The more we learned about each other, the more we would recognize that we’re all one. In an 1899 article celebrating the laying of transatlantic Western Union cables, a New York Times columnist expressed the popular assumption well: “Nothing so fosters and promotes a mutual understanding and a community of sentiment and interests as cheap, speedy, and convenient communication.”


The great networks of the 20th century — radio, telephone, TV — reinforced this sunny notion. Spanning borders and erasing distances, they shrank the planet. Guglielmo Marconi declared in 1912 that his invention of radio would “make war impossible, because it will make war ridiculous.” AT&T’s top engineer, J.J. Carty, predicted in a 1923 interview that the telephone system would “join all the peoples of the earth in one brotherhood.” In his 1962 book “The Gutenberg Galaxy,” the media theorist Marshall McLuhan gave us the memorable term “global village” to describe the world’s “new electronic interdependence.” Most people took the phrase optimistically, as a prophecy of inevitable social progress. What, after all, could be nicer than a village?

If our assumption that communication brings people together were true, we should today be seeing a planetary outbreak of peace, love, and understanding. Thanks to the Internet and cellular networks, humanity is more connected than ever. Of the world’s 7 billion people, 6 billion have access to a mobile phone — a billion and a half more, the United Nations reports, than have access to a working toilet. Nearly 2 billion are on Facebook, more than a billion upload and download YouTube videos, and billions more converse through messaging apps like WhatsApp and WeChat. With smartphone in hand, everyone becomes a media hub, transmitting and receiving ceaselessly.

Yet we live in a fractious time, defined not by concord but by conflict. Xenophobia is on the rise. Political and social fissures are widening. From the White House down, public discourse is characterized by vitriol and insult. We probably shouldn’t be surprised.

For years now, psychological and sociological studies have been casting doubt on the idea that communication dissolves differences. The research suggests that the opposite is true: free-flowing information makes personal and cultural differences more salient, turning people against one another instead of bringing them together. “Familiarity breeds contempt” is one of the gloomiest of proverbs. It is also, the evidence indicates, one of the truest.

In a series of experiments reported in the Journal of Personality and Social Psychology in 2007, Harvard psychologist Michael Norton and two colleagues found that, contrary to our instincts, the more we learn about someone else, the more we tend to dislike that person. “Although people believe that knowing leads to liking,” the researchers wrote, “knowing more means liking less.” Worse yet, they found evidence of “dissimilarity cascades.” As we get additional information about others, we place greater stress on the ways those people differ from us than on the ways they resemble us, and this inclination to emphasize dissimilarities over similarities strengthens as the amount of information accumulates. On average, we like strangers best when we know the least about them.


An earlier study, published in 1976, revealed a similar pattern in communities. Three professors from the University of California at San Diego studied a condominium development near Los Angeles, charting relationships among neighbors. They discovered that as people live more closely together, the likelihood that they’ll become friends goes up, but the likelihood that they’ll become enemies goes up even more. The scholars traced the phenomenon to what they called “environmental spoiling.” The nearer we get to others, the harder it becomes to avoid evidence of their irritating habits. Proximity makes differences stand out.

The effect intensifies in the virtual world, where everyone is in everyone else’s business. Social networks like Facebook and messaging apps like Snapchat encourage constant self-disclosure. Because status is measured quantitatively online, in numbers of followers, friends, and likes, people are rewarded for broadcasting endless details about their lives and thoughts through messages and photographs. To shut up, even briefly, is to disappear. One study found that people share four times as much information about themselves when they converse through computers as when they talk in person.


Being exposed to this superabundance of personal information can create an oppressive sense of “digital crowding,” a group of British scholars wrote in a 2011 paper, and that in turn can breed stress and provoke antisocial reactions. “With the advent of social media,” they concluded, “it is inevitable that we will end up knowing more about people, and also more likely that we end up disliking them because of it.”

If social media brings out the misanthrope in us, it can also unleash darker impulses. In a 2014 article in Personality and Individual Differences, three Canadian psychologists reported on research that found that people with sadistic tendencies tend to be among the most active commenters in online forums. Like other sadists, so-called trolls are motivated by the anticipation of pleasure, the study revealed; they take joy in inflicting psychic pain on others. Although it’s not clear whether the Internet breeds cruelty or just encourages it, the findings “add to accumulating evidence linking excessive technology use to antisociality,” the researchers wrote. “Sadists just want to have fun . . . and the Internet is their playground!”

Despite his occasional utopian rhetoric, Marshall McLuhan himself harbored few illusions about life in a global village. He saw villages as inherently tribal, marked by mistrust and friction and prone to viciousness and violence. “When people get close together, they get more and more savage and impatient with each other,” he said in a 1977 television interview. “The global village is a place of very arduous interfaces and very abrasive situations.” That’s a pretty good description of where we find ourselves today.

Still, the yearning to see communications technology as a remedy for social ills remains strong, as Zuckerberg’s February missive underscores. Despite Facebook’s well-publicized recent struggle to control hate speech, propaganda, and fake news, Zuckerberg seems more confident than ever that a “global community” can be constructed out of software. The centerpiece of his new project is a computerized “social infrastructure” that will use artificial-intelligence routines to manage information flows in a way that makes everyone happy. The system will promote universal self-expression while at the same time shielding individuals from “objectionable content.”


The problem with such geeky grandiosity goes beyond its denial of human nature. It reinforces the idea, long prevalent in American culture, that technological progress is sufficient to ensure social progress. If we get the engineering right, our better angels will triumph. It’s a pleasant thought, but it’s a fantasy. Progress toward a more amicable world will require not technological magic but concrete, painstaking, and altogether human measures: negotiation and compromise, a renewed emphasis on civics and reasoned debate, a citizenry able to appreciate contrary perspectives. At a personal level, we may need less self-expression and more self-examination.

Technology is an amplifier. It magnifies our best traits, and it magnifies our worst.

What it doesn’t do is make us better people. That’s a job we can’t offload on machines.

Nicholas Carr is the author of “Utopia Is Creepy,” “The Shallows,” and other books.