According to Lewis, the capitalist wage is approximately 30% more than subsistence earnings. This gap is considered necessary to induce the transformation from the subsistence sector to make up for the higher cost of living in an urban area or the psychological cost of transfer. As the marginal product of labor is negligible or zero, the wage in the subsistence sector remain constant at a subsistent level. Therefore, once again the wage in the capitalist sector also remains constant. In the capitalist sector, labor is hired up to the point where the marginal product is equal to the wage in order not to reduce the capitalist surplus. Since labor supply exceeds demand and the wage remains constant at subsistence level, the rate of profits is maximized. Also, profit minded capitalists are assumed to reinvest all profits to create new capital at a maximum rate. Then capital expansion leads to new employment.
Further, since the model primarily hypotheses that there are many nations with surplus supplies of labor and most times unlimited; they are all available at a subsistence wage. Lewis claimed that workers mainly contribute to economic development as: subsistence agriculture workers, causal labors, petty traders, and domestic services, women in the household and a general population increase. Also, the subsistence wage where the surplus labor is unlimited would be the equal to the minimum wage set by the state and/or may equal to average product per man in subsistence agriculture. .
Figure 1: capital accumulation with increase in employment in the modern sector.
However Figure 1, in this case, the diagram demonstrates the axiom of how economies employment expands in the 'capitalist' sector as capital formation occurs and the stock of capital increases in the same sector. Also, capital formation and increase in profits of the capitalists sector may not raise the wages of the normal working man, but will most likely raise profits for the capitalist sector, this will happen in the short run and the normal working man will only benefit in the long run when labor supply is exhausted (this would be discuss later).