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Many of the things that keep our democracy healthy don’t appear in the Constitution or any federal law. President Obama made this point Monday when talking about an orderly transition from one presidency to the next:

“It’s not something that the Constitution explicitly requires but it is one of those norms that are vital to a functioning democracy, similar to norms of civility and tolerance and a commitment to reason and facts and analysis.”

The last few words of that sentence were the ones that caught my attention, and I started thinking about them again after reading an Op-Ed by Zeynep Tufekci.

Tufekci, a University of North Carolina professor, makes the case that Facebook is in denial about its role in spreading misinformation. During the presidential campaign, Facebook helped spread falsehoods — the Pope endorsed Trump! — to millions of people. Those falsehoods appeared in fake news articles, and Facebook did nothing to inform their users that the material in them was simply made up.