<p>There are 19 centibillionaires and a growing list of 3,000 billionaires worldwide. So it might not surprise you that the richest one per cent possesses nearly half of the world’s wealth. History has never seen such an extreme concentration of wealth. Some economists argue the battle of the 21st century is between oligarchy and democracy. How did we get here? <em>IDEAS</em> begins a four-part documentary series The Billionaire Age.</p><p><br></p><p>Guests in this episode:</p><p><br></p><p>Ingrid Robeyns is a philosopher and economist. She is the chair in Ethics of Instutions at Utrecht University and the author of <em>Limitarianism: The Case Against Extreme Wealth</em>.</p><p><br></p><p>Lucas Chancel is the co-director of The World Inequality Lab and a professor at the Paris School of Economics.</p><p><br></p><p>Gabriel Zucman is also the co-director of The World Inequality Lab. He is a professor at the Paris School of Economics and the University of California, Berkeley.</p><p><...