Althusser and his collaborators are, therefore, profoundly correct in showing the presence of a genuine structure in Capital, and in rejecting historicist interpretations of Marxism, since this structure never acts transitively, following the order of succession in time; rather, it acts by incarnating its varieties in diverse societies and by accounting for the simultaneity of all the relations and terms which, each time and in each case, constitute the present: that is why 'the economic' is never given properly speaking, but rather designates a differential virtuality to be interpreted, always covered over by its forms of actualisation; a theme or 'problematic' always covered over by its cases of solution.