Thomas Jefferson often argued that an educated public was crucial for the survival of self-government. We now live in an age in which that education takes place mostly through relatively new platforms. Social networks — Facebook, Twitter, Instagram, etc. — are the main mechanisms by which people receive and share facts, ideas and opinions. But what if they encourage misinformation, rumors and lies?

In a comprehensive new study of Facebook that analyzed posts made between 2010 and 2014, a group of scholars found that people mainly shared information that confirmed their prejudices, paying little attention to facts and veracity. (Hat tip to Cass Sunstein, the leading expert on this topic.) The result, the report says, is the “proliferation of biased narratives fomented by unsubstantiated rumors, mistrust and paranoia.” The authors specifically studied trolling — the creation of highly provocative, often false information, with the hope of spreading it widely. The report says that “many mechanisms cause false information to gain acceptance, which in turn generate false beliefs that, once adopted by an individual, are highly resistant to correction.”

As it happens, in recent weeks I was the target of a trolling campaign and saw exactly how it works. It started when an obscure website published a post titled “CNN host Fareed Zakaria calls for jihad rape of white women.” The story claimed that in my “private blog” I had urged the use of American women as “sex slaves” to depopulate the white race. The post further claimed that on my Twitter account, I had written the following line: “Every death of a white person brings tears of joy to my eyes.”

Disgusting. So much so that the item would collapse from its own weightlessness, right? Wrong. Here is what happened next: Hundreds of people began linking to it, tweeting and retweeting it, and adding their comments, which are too vulgar or racist to repeat. A few ultra-right-wing websites reprinted the story as fact. With each new cycle, the levels of hysteria rose, and people started demanding that I be fired, deported or killed. For a few days, the digital intimidation veered out into the real world. Some people called my house late one night and woke up and threatened my daughters, who are 7 and 12.

It would have taken a minute to click on the link and see that the original post was on a fake news site, one that claims to be satirical (though not very prominently). It would have taken simple common sense to realize the absurdity of the charge. But none of this mattered. The people spreading this story were not interested in the facts; they were interested in feeding prejudice. The original story was cleverly written to provide conspiracy theorists with enough ammunition to ignore evidence. It claimed that I had taken down the post after a few hours when I realized it “receive[d] negative attention.” So, when the occasional debunker would point out that there was no evidence of the post anywhere, it made little difference. When confronted with evidence that the story was utterly false, it only convinced many that there was a conspiracy and coverup.

In my own experience, conversations on Facebook are somewhat more civil, because people generally have to reveal their identities. But on Twitter and in other places — the online comments section of The Post, for example — people can be anonymous or have pseudonyms. And that is where bile and venom flow freely. The Post’s Dana Milbank recently quoted a tweet about a column of his that said, “Let’s not mince words: Milbank is an anti-white parasite and a bigoted kike supremacist.” The comments about me were often nastier.

Elizabeth Kolbert, writing in the New Yorker, recalled an experiment performed by two psychologists in 1970. They divided students into two groups based on their answers to a questionnaire: high prejudice and low prejudice. Each group was told to discuss controversial issues such as school busing and integrated housing. Then the questions were asked again. “The surveys revealed a striking pattern,” Kolbert noted. “Simply by talking to one another, the bigoted students had become more bigoted and the tolerant more tolerant.” This “group polarization” is now taking place at hyper speed, around the world. It is how radicalization happens and extremism spreads.

I love social media. But somehow we have to help create better mechanisms in it to distinguish between fact and falsehood. No matter how passionate people are, no matter how cleverly they can blog or tweet or troll, no matter how viral things get, lies are still lies.

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