Work hard, children are told, and you will succeed. In recent decades this advice served the talented and the diligent well. Many have made their own fortunes and live comfortably, regardless of how much money they inherited. Now, however, the importance of hereditary wealth is rising around the rich world, and that is a problem.

People in advanced economies stand to inherit around $US6 trillion ($9.6 trillion) this year – about 10 per cent of GDP, up from around 5 per cent on average in a selection of rich countries during the middle of the 20th century. As a share of output, annual inheritance flows have doubled in France since the 1960s, and nearly trebled in Germany since the 1970s.