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My colleague Kevin Roose excels at explaining how our behavior is shaped by the companies behind our favorite online hangouts.

In the first episode of Kevin’s new audio series, called “Rabbit Hole,” he tells us how Caleb Cain, a college dropout in West Virginia, found himself watching ever more extreme YouTube videos. Caleb said he started to believe the racism, misogyny and conspiracy theories he absorbed.

People believe in fringe ideas for complex reasons. But Kevin points some blame at YouTube and its feature that recommends one video after another. This can push people from relatively mainstream videos toward dangerous ideas.

Our conversation about this, and more:

Aren’t most of us on YouTube for cooking videos and kittens, not conspiracies?

Kevin: People watch more than a billion hours of YouTube videos daily. While we can’t know how much of that is disturbing or dangerous, it’s inevitably a huge amount. And for a long time, people like Alex Jones and propaganda networks like RT had millions of subscribers and hundreds of millions of views.