The real sting here isn't the sentiment that we matter—that's comforting enough. King is pointing to something more unsettling: the complete *absence* of feedback. You might change someone's life by returning a library book, or lose someone's trust through a forgotten birthday, and never know it happened. A teacher once told me I'd make a good writer, something I dismissed for years; only much later did I realize I'd already become one, shaped by that casual remark I'd almost forgotten. We live in a strange economy where our currency—influence—keeps circulating invisibly, and we're forced to act as though our kindnesses matter even when we'll never receive a receipt.