success story in which hundreds of millions of Chinese have been lifted out of abject poverty over the past few decades. Never in human history have so many seen so much progress. Although this is a remarkable story, it is not entirely unprecedented. From 1840 to 1910, British workers also experienced a marked rise in their standard of living. And this success was repeated soon afterward in the United States, setting the stage for the high levels of prosperity we now enjoy. Commenting on how English workers were lifted out of poverty, the great economist Alfred Marshall made a_n_ observation that is equally relevant for Chinese workers today: \"The hope that poverty and ignorance may gradually be extinguished, derives indeed much support from the steady progress of the working classes during the nineteenth century.\" These unprecedented sets of events have touched our lives today in a dizzying number of ways. You are using smartphones, tablets, and laptops that are manufactured in the PRD as you purSue a rst-rate education in the United States, one of the richest countries in the world. What can economics say about all of this? Quite a lot, it turns out. What you will learn from this book is how these momentous changes, which lifted hundreds of millions of people out of poverty, are related to a simple, but very important, set of questions involving economics. Among these questions are: - How does Our economic system work? That is, how does it manage to deliver the goods? - When and why does our economic system sometimes go astray, leading people into counterproductive behavior? - Why are there ups and downs in the economy? That is, why does the economy sometimes have a bad year? . Why is the long run mainly a story of ups rather than downs? That is, why has China, like Great Britain and the United States, become much richer over time? Let's t_a=k_e a_l_o_qk_ at these questions and offer a brief preview of what you will learn in this book. 0 INTRODUCTION:An Engine for Growth andl Discovery A DAY IN THE MEGACITY LONDON, NEW YORK, AND TOKYO have something in common: they are megacities huge metropolitan complexes that contain tens of millions of people and are spread over immense tracts of land. While most people are familiar with these megacities, not everyone knows about the biggest of them all: the vast urban complex known as China's Pearl River Delta (the PRD). Roughly the same size as the state of Delaware, the PRD is home to more than 65 million people. Driving across the PRD (as one of the authors has done), with its endless succession of factories, ofce buildings, and apartment towers, is an unforgettable and very long experience. Thirty years gag China was very poor with a backward economy. Now it produces sophisticated goods for the world, allowing it to deliver relatively comfortable incomes to many of its people. The rst photo shows the sparse development of China thirty years ago, along the Pearl River Delta. The second photo shows the same region packed with high-rise buildings. What are all those people doing? A signicant percentage of them are engaged in producing goods for world markets, especially, but by no means only, electronic components: just about every smartphone, tablet, and computer contains components produced in the PRD. But the megacity's residents are consumers as well as producers. While the wage of an average worker in the PRD is relatively low by U.S. standards, overall wages and income are high enough to support a vast retail sector, ranging from mom-and-pop local stores to shops selling expensive luxury goods. But not so long ago, neither the PRD nor the economic dynamism it embodies was visible. As recently as 1980, 800 million people in China subsisted on less than $1.50 a day. The average Chinese citizen more orJesshad enough to eat and a roof over his or her head, but not much more than that. In fact, the standard of living wasn't much higher than it had been centuries earlier. And from 1959 to 1961, in what is now known as \"The Great Leap Backward,\" the Chinese government got the economy so wrong that millions of Chinese died from man-made famine. However, in the years since 1980, Chinese incomes have soared more than twentyfold in real terms as the poverty rate (percentage of the population subsisting on less than $1.90 a day) has fallen from 88% in 1981 to 0.2% in 2015. The rise of the PRD is one chapter of an incredible