What will the interactions among all the forces of social, political, and economic change mean for society going forward? Dee Smith puts the pieces together in the fifth and final episode of A World on the Brink, looking at what might be the ultimate causes of these changes and also exploring the crucial question of whether, and to what extent, the current systems and structures of the world will hold. Ultimately, the role of human nature and a look at history lend cause for both concern and for hope.