For millennia, the road to wealth was to win wars and plunder. Until 1820, world growth per capita was approximately zero. During the century after the fall of the Roman Empire, prosperity in Europe had actually declined and most critical technologies had disappeared – the most important being cement, which would not be rediscovered until much later. But not long after 1820, prosperity began to increase, and for each generation, life became noticeably more comfortable. During the 172 years after 1820, the world’s GDP increased eightfold. During the same 172-year period, GDP in the United Kingdom rose 10x and in the United States 20x. Economic growth is synonymous with increased productivity, which is almost exclusively the result of technological progress.
A summary of the book can be read here.