This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
In 1954, W. Arthur Lewis, then teaching at the University of Manchester, published a paper modeling a problem no existing economic theory addressed well: an economy split between a traditional subsistence sector, where so much labor was employed that removing some workers cost almost nothing in lost output, and a modern industrial sector that could draw on that surplus labor at a roughly constant wage. As industry expanded and reinvested its profits, it would keep absorbing labor from the traditional sector until the surplus was exhausted and wages began to rise.
The dual-sector model gave newly independent governments across Africa, Asia and the Caribbean, most of them facing exactly this structure, a formal framework for thinking about industrialization rather than a set of borrowed assumptions from already-industrialized Britain or the United States. Lewis, born in Saint Lucia in the British West Indies, brought direct experience of colonial economic administration to the theory and went on to advise the governments of Ghana and several other states.
Later development economists, including Amartya Sen, pushed back against reducing development to capital accumulation and wage convergence alone, arguing that capabilities, health, education, freedom, mattered as much as income. But Lewis's model remains the field's founding formal statement, the reason development economics has its own textbooks rather than being taught as a footnote to growth theory, and the achievement that made him, in 1979, the first economist of African descent to win a Nobel Memorial Prize in Economic Sciences.