The Development Economists
The preoccupation of the orthodox economics was to answer the six fundamental questions: (i) will the society organized on the principles of exchange stay composed or will it fall apart (the question of existence of equilibrium)?, (ii) will such an equilibrium be unique (a multiplicity of equilibria poses difficult and embarrassing questions)?, (iii) will such an equilibrium be robust (the question of stability of equilibrium)?, (iv) will such an economy (society) be efficient?, (v) will it grow or expand forever?, and (vi) will it be just? The classical economists, Adam Smith in particular, answered all these questions affirmatively using their characteristic methodologies. However, Karl Marx challenged the entire structure of faith in the merits of the exchange economy and shattered all optimism regarding the said order. The neoclassicists, mostly using their own new (mathematical, marginalist, rationalistic, atomistic, hedonistic, etc) methodology set out to prove that answers to all those six questions were in affirmative. They restructured the faith in the said order, but at the cost of distancing themselves from the reality and they did not mind doing so. They advocated for free trade and argued that trade would be beneficial to all, even to those economies that were poor and underdeveloped since they, too, had some sort of comparative advantages. Implicitly, they supported colonization of the underdeveloped countries by the developed ones.
The Keynesian, the Neo- and New Keynesian and even the Post-Keynesian economists as well as the economists of the Austrian and the Stockholm schools had nothing much to say on economic development of those economies that were caught in the vicious circle of poverty and underdevelopment. All those economists were the economists of the developed economies. It may be noted that the so-called theories of economic growth that appeared in the Post Great Depression period (including von Neumann's work) were the theories of expansion (question-v above) of the market-based developed economies with or without violent fluctuations in output and employment volumes. That is why we have no Economics of Development before the World War II ended.
However, after the World War II the scenario changed dramatically. By 1950, the World saw numerous countries, earlier only the colonies but then free nations, pondering over the possibilities of their economic development. The developed economies were divided into two blocs: the one that believed in the free (or at best managed) market-economies with little public intervention and the other that believed in the active and prominent state intervention or central control and planning to manage the national economies. It was natural that both the blocs would allure the nascent underdeveloped nations to join them. The economics of development evolved in this milieu.
In spite of the continued efforts of many economists attacking the problem of underdevelopment, much understanding of the process and problems of development is as yet evasive. Economists are busy at measuring poverty or describing the extent or severity of poverty, but the mechanism or process of pauperization is only poorly investigated. The institutions and the social rules that inhibit trickle down effect and reinforce or promote backwash effect of elitist(ic) development in a non-command economy are only poorly understood or purposefully obfuscated. Hence, Development Economics is attracting many new authors working with different ideologies. Much of their works may be free downloaded. The World Institute for Development Economics Research (WIDER) provides a very rich information on development and poverty issues in various countries.