“And it is why so many of us who use Facebook are still troubled by its siren song: it is a simulacrum of intimacy, a simulacrum of mutual understanding, not the real thing. The pattern of what people like or don’t like tells us something about them—more, in fact, than they may wish. But it doesn’t tell us why they like what they like. It doesn’t allow us to understand them. Facebook knows, but doesn’t understand.”