What will the world look like in 100 years?” wondered Ignacio Palacios-Huerta. Being an economist at the London School of Economics, he put this question to other economists. Admittedly, the profession didn’t foresee the financial crisis but, still, he writes in the introduction to his new book, economists “know more about the laws of human interactions and have reflected more deeply and with better methods than any other human beings”. (Declaration of interest: I once tried to market Palacios-Huerta’s insights into penalty-kicks to football clubs. Nobody ever paid us.)

Economists liked his question. “Hi Ignacio:” emailed Alvin Roth, Nobel laureate of 2012. “To my surprise, I do find your invitation tempting. It’s a sign of old age, I’m afraid.” The economists who volunteered to write chapters included two other Nobel-winners. The resulting book, In 100 Years, suggests some probable contours of our great-grandchildren’s world, among them:

Greater longevity will push us to reshape our lives. Over the past century, life expectancy in the west has risen by about 30 years. In another century the average person could be living to 100 – perhaps even in currently poor countries, which are already making quick gains by saving infants from simple illnesses such as diarrhoea.