The dual economy model, built on classical foundations, served as the cornerstone of development theory for several decades after World War II. It subsequently came under neo-classical micro-econometric attack and has fallen into general disuse, at least within the Anglo-Saxon academic...

Arthur Lewis' seminal 1954 paper and its emphasis on dualism appeared at a time when neither the work of Keynes or Harrod-Domar nor the later neoclassical production function of Solow seemed relevant for developing countries. As a consequence, his model, rooted in the classical tradition, plus...

This paper argues that dual economy models deserve a central place in the analysis of growth in developing countries. The paper shows how these models can be used to analyse the output losses associated with factor misallocation, aggregate growth in the presence of factor market distortions,...

We write this essay for both lay readers and scientists, though mainstream economists are welcome to enjoy it too. Our subject is the basic toolbox of mainstream economics. The most important tools in this box are demand, supply and equilibrium. All mainstream economists – as well as many...