Paul Volcker is the greatest man I have known. He is endowed to the highest degree with what the Romans called virtus (virtue): moral courage, integrity, sagacity, prudence and devotion to the service of country.” Thus did I open my review of his memoir, Keeping At It: The Quest for Sound Money and Good Government , published last year. As Hamlet said of his father, “He was a man, take him for all in all. I shall not look upon his like again.”

That book was Volcker’s counsel to the world. It embodied the former US Federal Reserve chairman’s virtues and his values. With his passing this week, we need to dwell on both, while recognising how different the world is today.

Volcker’s virtues are eternal. It is impossible to enjoy a stable polity without public servants of his quality and, as important, without a public who know they need public servants of this quality. In no other way can what the Romans called res publica (a republic) — literally, “the public thing” — be sustained. We rely on the marriage of ability to character. We forget that truth at our peril.