Marxists.org has several chapters from what looks to be an interesting book by Kuruma on Marx’s theory of crisis, that stresses its systematic and unfinished nature:
‘Marx’s general grasp of crisis—as in the case of other problems he deals with—is both the outcome of a certain investigation he carried out and at the same time useful as a guiding principle for further research. This general understanding of crisis is directly expressed in the following propositions.
The commercial crises of the nineteenth century, and in particular the great crises of 1825 and 1836 [were] big storms on the world market, in which the antagonism of all elements in the bourgeois process of production explodes. (A Contribution to the Critique of Political Economy)
The world trade crises must be regarded as the real concentration and forcible adjustment of all the contradictions of bourgeois economy. (Theories of Surplus Value)
In world market crises, all the contradictions of bourgeois production erupt collectively; in particular crises (particular in their content and in extent) the eruptions are only sporadically, isolated and one-sided. (Theories of Surplus Value)’
Marx’s grasp of crisis expressed above naturally determines his entire plan for the clarification of crisis. Because crisis is the concentrated explosion of all of the contradictions of capitalistic production, to concretely grasp crisis as such, one must first unfold all of the contradictions of capitalistic production according to their internal relations, and thus the significance of each contradiction as a moment within the totality must be elucidated, and then next one must clarify what processes they pass through and in what sense they must explode in a concentrated manner. And this is above all precisely what Marx sought to achieve throughout his entire critique of political economy (of which Capital is the most basic part). In other words, Capital at the same time can be said to include a theory of crisis (its most fundamental part).
Read the rest here.