This year, the adage that ''falsehood flies and the truth comes limping after it'' doesn't begin to describe the problem. That idea assumes that the truth eventually catches up. There's not much evidence of this happening for the millions of people taken in by the fake news stories -- like Pope Francis endorsing Donald Trump or Mr. Trump pulling ahead of Hillary Clinton in the popular vote -- that have spread on social media sites.
Most of the fake news stories are produced by scammers looking to make a quick buck. The vast majority of them take far-right positions. But a big part of the responsibility for this scourge rests with internet companies like Facebook and Google, which have made it possible for fake news to be shared nearly instantly with millions of users and have been slow to block it from their sites.
Mark Zuckerberg, the founder and chief executive of Facebook, has dismissed the notion that fake news is prevalent on his platform or that it had an influence on the election. But according to a BuzzFeed News analysis, during the last three months of the presidential campaign, the 20 top fake news stories on Facebook generated more engagement -- shares, likes and comments -- than the 20 top stories from real news websites.
These hoaxes are not just bouncing around among like-minded conspiracy theorists; candidates and elected officials are sharing them, too. Senator Ben Sasse, Republican of Nebraska, on Thursday tweeted about people who have been paid to riot against Mr. Trump -- an idea propagated by fake news stories. A man who wrote a number of false news reports told The Washington Post that Trump supporters and campaign officials often shared his false anti-Clinton posts without bothering to confirm the facts and that he believes his work may have helped elect the Republican nominee.
Abroad, the dissemination of fake news on Facebook, which reaches 1.8 billion people globally, has been a longstanding problem. In countries like Myanmar, deceptive internet content has reportedly contributed to ethnic violence. And it has influenced elections in Indonesia, the Philippines and elsewhere. Social media sites have also been used to spread misinformation about the referendum on the peace deal in Colombia and about Ebola in West Africa.
Facebook says it is working on weeding out such fabrications. It said last Monday that it would no longer place Facebook-powered ads on fake news websites, a move that could cost Facebook and those fake news sites a lucrative source of revenue. Earlier on the same day, Google said it would stop letting those sites use its ad placement network. These steps would help, but Facebook, in particular, owes its users, and democracy itself, far more.
Facebook has demonstrated that it can effectively block content like click-bait articles and spam from its platform by tweaking its algorithms, which determine what links, photos and ads users see in their news feeds. Nobody outside the company knows exactly how its software works and why you might see posts shared by some of your friends frequently and others rarely. Recently, the company acknowledged that it had allowed businesses to target or exclude users for ads for housing, employment and credit based on their ethnicity, in apparent violation of anti-discrimination laws. It has said it will stop that practice.
Facebook managers are constantly changing and refining the algorithms, which means the system is malleable and subject to human judgment. This summer, Facebook decided to show more posts from friends and family members in users' news feeds and reduce stories from news organizations, because that's what it said users wanted. If it can do that, surely its programmers can train the software to spot bogus stories and outwit the people producing this garbage.
Blocking misinformation will help protect the company's brand and credibility. Some platforms have suffered when they have failed to address users' concerns. Twitter users, for instance, have backed away from that platform because of abusive trolling, threatening posts and hate speech, which the company hasn't been able to control.
Mr. Zuckerberg himself has spoken at length about how social media can help improve society. In a 2012 letter to investors, he said it could ''bring a more honest and transparent dialogue around government that could lead to more direct empowerment of people, more accountability for officials and better solutions to some of the biggest problems of our time.''
None of that will happen if he continues to let liars and con artists hijack his platform.
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DRAWING (DRAWING BY MERTO/WILLEY)