A Note on Sources and Terminology

This is a book for non-specialists. I’ve tried to steer clear of endless footnotes. The articles that I refer to in the text are cited in the endnotes, but I do not identify every single source I’ve consulted.

I am an empirical social scientist. Throughout the book, I rely heavily on open access GDP and other development statistics. For the sake of consistency, I use the World Bank’s World Development Indicators wherever possible. For estimates earlier than the 1960s, I rely on the Maddison Project. Both maintain online repositories that are freely accessible. I also owe a huge debt of gratitude to Max Roser of ourworldindata.org. His data, and figures and maps, are freely downloadable and provide a wonderful public resource for the social science community. For anyone still in doubt about the astounding progress humankind has made over the last two hundred years, just spend a few minutes on this site. For figures published in copyrighted journal articles, I have downloaded the replication data from the authors and redrawn the graphs in R.