James Madison traveled to Philadelphia in 1787 with Athens on his mind. He had spent the year before the Constitutional Convention reading two trunkfuls of books on the history of failed democracies, sent to him from Paris by Thomas Jefferson. Madison was determined, in drafting the Constitution, to avoid the fate of those “ancient and modern confederacies,” which he believed had succumbed to rule by demagogues and mobs.

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Madison’s reading convinced him that direct democracies—such as the assembly in Athens, where 6,000 citizens were required for a quorum—unleashed populist passions that overcame the cool, deliberative reason prized above all by Enlightenment thinkers. “In all very numerous assemblies, of whatever characters composed, passion never fails to wrest the sceptre from reason,” he argued in The Federalist Papers, the essays he wrote (along with Alexander Hamilton and John Jay) to build support for the ratification of the Constitution. “Had every Athenian citizen been a Socrates, every Athenian assembly would still have been a mob.”

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Still, some promising, if modest, fixes are on the horizon. Nathaniel Persily, a professor at Stanford Law School who leads an independent commission that will examine the impact of Facebook on democracy, notes one step the company has taken to address the problem of “clickbait,” which lures users with sensational headlines. Articles that persuade many users to click previously appeared high on Facebook’s News Feed. The company now prioritizes those articles users have actually taken the time to read.

But these and other solutions could have First Amendment implications. “The democratic character of the internet is itself posing a threat to democracy, and there’s no clear solution to the problem,” Persily told me. “Censorship, delay, demotion of information online, deterrence, and dilution of bad content—all pose classic free-speech problems, and everyone should be concerned at every step of the government regulatory parade.”