Fitzgerald isn't praising mere tolerance of disagreement—he's describing something rarer: the mental stamina to resist premature closure. Most people hold opposing views by compartmentalizing them, keeping each in a separate box. What he means is harder: sitting with genuine contradiction without forcing false resolution, like a parent who loves a child deeply while also recognizing genuine ways that child has disappointed them. The intelligence lies not in splitting the difference or declaring one side right, but in refusing the comfort of certainty while still moving forward with your life.