Furthermore, following the ideas of Marx, Robinson and Sraffa argued that the rate of profit was not the reward for productive contribution of ‘capital’; it derived from social relations, that’s to say, who owned the means of production and who was forced to work for them. The circularity of the logic of neoclassical theory was partly accepted by Samuelson in a well-known 1966 article in the prestigious Quarterly Journal of Economics, where he admitted the logical validity of the points being made by Robinson and Sraffa.
