When Adam Smith published 'The Wealth of Nations' in 1776, there were fewer than one billion people alive, and in dollar terms, size of the global economy was three hundred times smaller than it is today. When Paul Samuelson published 'Economics' in 1948, there were not yet three billion people on earth, and the global economy was still ten times smaller than it is today. In the twenty-first century, we have left behind the era of the 'Empty World' when the flow of energy and matter through the global economy with small of relation to the capacity of nature's sources and sinks. We live now, says Daly, in 'Full World', with an economy that exceeds Earth's regenerative and absorptive capacity by over-harvesting sources such as fish and forests, and overfilling sinks such as the atmosphere and oceans.

— Doughnut Economics: Seven Ways to Think Like a 21st-Century Economist by Kate Raworth (Page 65)