In 1928, the poet Paul Valéry had a vision of the future: “Just as water, gas, and electricity are brought into our houses from far off to satisfy our needs in response to a minimal effort, so we shall be supplied with visual or auditory images, which will appear and disappear at a simple movement of the hand, hardly more than a sign.”

I copied this quote into my notebook five years ago, and it still knocks me over whenever I come across it. Today we can let the entire world—and everyone’s opinions about it—into our heads with a swipe or a click. Of course we’re going to feel a little crazy. Perhaps screens have become our reality, and the physical world only exists to serve their needs. This is a loopy sensation rather than a coherent idea, and I clearly need to step up my information hygiene.

But back to Paul Valéry, who might be the patron saint of blogging. Each morning for fifty years, he would record his thoughts, theories, and questions in his notebooks, which became a sprawling collection of meditations on psychology, metaphysics, history, poetry, and the mundane. “Having dedicated those hours to the life of the mind,” he wrote, “I thereby earn the right to be stupid for the rest of the day.