Former President Barack Obama took the stage at Stanford University on Thursday to deliver a keynote addressing disinformation and the dangers it poses to democracy.

Obama, whose campaign successfully used social media to raise awareness of his agenda, touched on everything from social networks and their algorithms to the First Amendment and the war in Ukraine.

"Not all problems we are seeing now are an inevitable byproduct of this new technology," he said. "They’re also the result of very specific choices made by the companies that have come to dominate the internet, generally, and social media platforms in particular — decisions that intentionally or not have made democracies more vulnerable."

Still, Obama pointed out that society's divisions, from sexism and racism to ethno-nationalism, didn't form on social networks like Facebook, Instagram, Twitter, or TikTok. They're simply amplified there thanks to their millions of users.

"Our blind spots, our prejudices aren't challenged, they're reinforced," he said.

That assertion has been backed up by documents revealed by Facebook (FB) whistleblower Frances Haugen, which showed that divisive content drives user engagement on social media platforms.

Obama, however, didn't lay the blame for the spread of disinformation solely at the feet of social networks. Instead, he said many forms of disinformation originate on traditional media platforms and that social networks have helped accelerate the decline of newspapers and traditional news sources.

As for solutions, Obama called on platform owners to be more transparent about how their algorithms function, something both Democrats and Republicans in Congress have repeatedly demanded.

What's more, he pushed back against calls to further regulate speech on social platforms, saying "Freedom of speech is at the heart of every democratic society."

Democrats in Congress have repeatedly admonished platforms including Facebook, YouTube (GOOG, GOOGL), TikTok, and Twitter (TWTR) for allowing the spread of disinformation, and called on them to improve content moderation practices. However, platforms receive broad immunity for user-generated content thanks to Section 230 of the Communications Decency Act.

Many Republicans, meanwhile, have railed against social media sites for removing content that violates their terms of service, claiming it impedes users’ free speech rights. Again, however, platforms are protected because content moderation is a form of free speech.

For his part, Obama said that an exchange of antagonistic ideas often leads to a healthier society.