I went through Chris Blattman’s excellent reading list on “African Poverty and Western Aid”, and it entered  my top-10 list of “courses-I-wished-I-could-take-but-probably-never-will”. It comes just after Tyler Cowen’s Law and Literature course at George Mason University  (first compulsory reading is the Holy Bible and the last is the Thanatos Syndrome .. !)

Chris recommends one of Paul Krugman’s classic essays “The Fall and Rise of Development Economics” (he also blogged about it here).  For some reasons I hadn’t read it before, but I warmly recommend it to anyone involved in international development. There is also a comprehensive (and rather leftist) review here.

The essay basically divides the evolution of development economics in two phases: First, the so-called High Development Theory started from Rosenstein-Rodan “Big Push Model” (1943) up to Hirschman’s Strategy of Economic Development (1958), which he considers the “fall” of development economics.

the crisis of high development theory in the late 1950s was neither empirical nor ideological: it was methodological. High development theorists were having a hard time expressing their ideas in the kind of tightly specified models that were increasingly becoming the unique language of discourse of economic analysis. They were faced with the choice of either adopting that increasingly dominant intellectual style, or finding themselves pushed into the intellectual periphery. They didn’t make the transition, and as a result high development theory was largely purged from economics, even development economics.

The rise occurred in the late ’80s when rigorous models started to appear in development economics. The famous paper by Murphy, Shleifer, and Vishny (1989) created a very simple model made of  “three pages, two equations, and one diagram” and it explained the 50-years-old Big Push theory with the use of some math .. And development theory found a place in mainstream economics.

One of the most interesting passages is “The Evolution of Ignorance“, where Krugman compares development economics to the evolution of African maps between 15th and 19th centuries.

In the 15th century, maps of Africa were, of course, quite inaccurate about distances, coastlines, and so on. They did, however, contain quite a lot of information about the interior, based essentially on second- or third-hand travellers’ reports. Thus the maps showed Timbuktu, the River Niger, and so forth. Admittedly, they also contained quite a lot of untrue information, like regions inhabited by men with their mouths in their stomachs. Still, in the early 15th century Africa on maps was a filled space.

Over time, the art of mapmaking and the quality of information used to make maps got steadily better. The coastline of Africa was first explored, then plotted with growing accuracy, and by the 18th century that coastline was shown in a manner essentially indistinguishable from that of modern maps. Cities and peoples along the coast were also shown with great fidelity. […]

It should be obvious what happened: the improvement in the art of mapmaking raised the standard for what was considered valid data. Second-hand reports of the form “six days south of the end of the desert you encounter a vast river flowing from east to west” were no longer something you would use to draw your map. Only features of the landscape that had been visited by reliable informants equipped with sextants and compasses now qualified. And so the crowded if confused continental interior of the old maps became “darkest Africa”, an empty space.

Full paper