This is how these algorithms reinforce polarization in our society. We may think of ourselves as rational creatures, but deep in our brain is the impulse for survival, and it divides the world into us vs. them. Anger and outrage are easily spiked. You can’t help yourself but click on that video of Richard Spencer getting punched. Politicians may seem extreme. But they are just responding to the public—and the anger we are working up daily in our news feeds, our march to one extreme.

