Thomas Piketty’s “Capital” summarised in four paragraphs

via The Economist;

As a general rule wealth grows faster than economic output, he explains, a concept he captures in the expression r > g (where r is the rate of return to wealth and g is the economic growth rate). Other things being equal, faster economic growth will diminish the importance of wealth in a society, whereas slower growth will increase it (and demographic change that slows global growth will make capital more dominant). But there are no natural forces pushing against the steady concentration of wealth. Only a burst of rapid growth (from technological progress or rising population) or government intervention can be counted on to keep economies from returning to the “patrimonial capitalism” that worried Karl Marx. Piketty closes the book by recommending that governments step in now, by adopting a global tax on wealth, to prevent soaring inequality contributing to economic or political instability down the road.