Few ideas are more unshakable than the notion that the rich keep getting richer while ordinary folk fall ever farther behind. The belief that capitalism is rigged to benefit the wealthy and punish the workers has shaped how millions view the world, whom they vote for and whom they shake their fists at. It has been a spur to political projects on both left and right, from the interventionism of US President Joe Biden to the populism of Donald Trump. But is it true?

Even as the suspicion of free markets has hardened, evidence for the argument that inequality is rising in the rich world has become flimsier. Wage gaps are shrinking.