"'In the analysis of economic forms, neither microscopes or chemical reagents are of assistance. The power of abstraction must replace both.' Of course structuralism has frequently taken this proposition to its extreme. Because thought is impossible without 'the power of abstraction,' it has confused this with giving absolute primacy to the level of the formation of concepts - at the highest, most abstract level of abstraction only: Theory with a capital 'T' then becomes judge and jury. But this is precisely to lose the insight just won from Marx's own practice. For it is clear in, for example, Capital, that the method - whilst taking place 'in thought' (as Marx asked in the 1857 Introduction, where else?) - rests not on the simple exercise of abstraction but on the movement and relations which the argument is constantly establishing between different levels of abstraction: at each, the premises in play must be distinguished from those which - for the sake of argument - have to be held constant. The movement to another level of magnification (to deploy the microscope metaphor) requires the specifying of further conditions of existence not supplied at a previous, more abstract level: in this way, by successive abstractions of different magnitudes, to move towards the constitution, the reproduction, of 'the concrete in thought' as an effect of a certain kind of thinking. This method is adequately represented in neither the absolutism of Theoretical Practice, in structuralism, nor in the anti-abstraction 'Poverty of Theory' position...."
Doug