Duration, Intensity and Productivity of Labour and the Distinction between Absolute and Relative Surplus-value

Marx recognized two distinct but also interrelated processes of increasing surplus-value extraction: absolute and relative surplus-value. Both these processes hinge upon the duration, the intensity and the productivity of labour, albeit in different ways. The increase of the duration of labour is indisputably related to absolute surplus-value and the increase of labour productivity to relative surplus-value. However, there is controversy regarding the position of the intensity of labour. Marx's argument that it belongs to relative surplus-value is disputed by many Marxists. This paper argues that Marx's thesis is correct because the intensification of labour and the increase of its duration are ultimately two opposing trends and thus should not be coupled in the same concept.