The collapse of the once world-leading sugar industry, the need to send doctors to middle-income countries to boost foreign exchange receipts, the iconic status of 60-year-old cars as tourist attractions, the crumbling of buildings on streets that were once national showcases, the evident inability to maintain these buildings for the future, the writing-off of nearly all the external debt: it must be the case that Cuba is less productive and poorer, probably much poorer, than 55 years ago. Socialism was supposed to give Cubans prosperity, unity, fairness and freedom, but instead it has led to impoverishment, apartheid, division and oppression.

Yes, old habits die hard. For much of the 20th century French intellectuals quoted great chunks of Marx in difficult but allegedly epochal works, and bewailed the contradictions of capitalism. Indeed, London had entire bookshops devoted to literature of this sort, even if they depended, like Cuba, on Soviet subsidies to pay the bills. So what is one to make of a book, a bestseller in fact, that once more quotes Marx and bewails the contradictions of capitalism, as if the plainest lessons of the 20th century had never been? And, yet more extraordinary, what is one to think of the book's title, Capital in the Twenty-First Century, which is presumably meant to persuade the reader that it is forward-looking and even avant-garde?

Thomas Piketty claims that the market economy based on private property is subject to "a powerful destabilising force", with consequences for "the long-term dynamics of wealth distribution" that are "potentially terrifying". (He means that, when their investments yield a decent rate of return, rich people get richer. Surprise, surprise.)

Perhaps he should write another book on the long-term dynamics of wealth distribution in a planned economy based on state ownership, and so try to determine whether Communism is also vulnerable to "contradictions". In one respect writing that book would be much easier than the preparation of the 655-page tome from Harvard University Press that has just appeared under his name. Data and evidence from only two countries — Cuba and North Korea — would need to be examined, since the Soviet Union and Comecon disqualified themselves 20 years ago. And, like the people who have had to live in these unfortunate places for a few decades, he might find such data and evidence "potentially terrifying" too.