IT WAS ADORNO’S IDEA that capitalism had stripped philosophy of its revolutionary capacities. What was left was art, the last emancipator and partisan of truth. But Adorno was using the word “truth” (or Wahrheitsgehalt, “truth-value”) in a way that was already becoming outmoded. His “truth” always gestured toward an “essence,” a below-the-surface system of pitches, colors, or symbols that would organize an artwork and instantiate its worth; but contemporary usage was returning the word to its Enlightenment definition—quasi-scientific “factuality.” This is the position we’re in today, when most writers invoke “truth” only as a preemptive defense against those whose primary impulse is to fact-check and accuse.