Erik Brynjolfsson, a professor at MIT and a principal research scientist at the Institute for Quantitative Social Sciences, talks about his new book, "The Second Machine Age: Work, Progress and Prosperity in a Time of Brilliant Technologies." In it, he argues that technological change is transforming the way work is done and will continue to do so through the next century. Brynjolfsson discusses the impact of new digital technologies on the economy, including 3D printing, artificial intelligence and the sharing economy. He also discusses how the changing nature of work affects society as a whole.