Because tech companies like Facebook and Google make money off the sale of our personal data to advertisers, they depend on the attention of the masses to survive. And because their algorithms shape much of what we see online, it’s to their benefit to coerce us into thinking of ourselves not as individuals but as members of groups. “The big tech companies,” Franklin Foer writes, “Propel us to join the crowd—they provide us with the trending topics and their algorithms suggest that we read the same articles, tweets, and posts as the rest of the world.”