“As we have recalled many times, Marx was categorically opposed to any “iron law of wages” theory of the kind adopted by Malthus or Lassalle (and to some extent by Ricardo too), which in the last analysis rests upon demographic considerations. Wages are supposed always to fall to the physiological minimum as a result of variations in the supply of wage laborers due to birth-rate (or child survival) fluctuations. For Marx, by contrast, wages have two components: one physiological, and one “historical” or “social”. The former represents the lower limit below which wages cannot fall without threatening to make the working class, and hence capitalism itself, disappear. Similarly, the historical-social component has an upper limit beyond which wages cannot rise without making surplus value, and hence capitalism, disappear. But between the lower and the upper limit wages can and do fluctuate, as a function of what Marx called “the respective powers of the (class) combatants” (1)”  [Ernest Mandel, Long Waves of Capitalist Development. A Marxist Interpretation, 1995] [(1) W.W. Rostow, The World Economy, History and Prospects (Austin, 1978)]