Pulitzer Prize-winning author Jared Diamond is a world-renowned expert on ancient societies. His famous books, "Collapse" and "Guns, Germs and Steel", are studies of the choices societies have made throughout history in the face of change.
In this video, he speaks about the challenges facing our world today, drawing comparisons to other cultures and how they managed, or famously mismanaged, their environmental, economic and other challenges.
He says: "We have this opportunity to learn from remote places and to learn from places remote in time. No other society in world history has had that advantage. Of all the things that might incline me toward pessimism, that's the biggest thing that in the end run, inclines me toward optimism."