One of the surprise best selling books of the past couple of years has been Capital in the Twenty-First Century - a hefty work on inequality and wealth by French economist Thomas Piketty.
It argues that the stock market and real estate will grow faster than income, and that because you need money to acquire stocks and real estate in the first place, inequality is likely to increase.
So, how does this apply to India, often seen as a very unequal society but which is experiencing rapid growth that's lifting millions out of poverty?
He spoke to the BBC's Justin Rowlatt at the Jaipur Literature Festival in India.
