....first, that science should have generalizing claims. Second, the explanation of social phenomena by revealing the causal mechanisms that produce them is the fundamental task of research.
First, we want to make it clear that generalizing is not the same as universalizing. It is important to be able to develop an understanding of causation that goes beyond the unique instance — the object of ideographic inquiry. however, it is just as important to be able to specify the limits of that generalization. We cannot establish universal laws in the social sciences. There is no valid nomothetic project. We hope to demonstrate here that case-based methods help us both to elucidate causation and to specify the range of the applicability of our account of causal mechanism. The emphasis on the plural form of mechanism in the preceding sentence is very important. It is not just that different mechanisms operate to produce, contingently in context, different results. It is rather than different mechanism may produce the same outcome — the complete antithesis of the form of understanding that is implicit in, and foundational to, traditional statistical modeling's search for the — that is to say the universal, always and everywhere, nomothetic —model that fits the data.
Three levels of ontological interest are germane to sociological inquiry: (1) philosophical ontology, (2) scientific ontology, and (3) sociological ontology. Philosophical ontology deduces from the structure of speculative thought the fundamental nature of the entities that constitute our everyday world. Scientific ontologies are nested within philosophical ontologies to the extent that they flesh out the local details of a terrain in a way philosophical ontology cannot.... Finally, social ontologies are nested within scientific ontologies in that they deal with the elemental entities and dynamics sociohistorical formations must exhibit if they are to sustain themselves over time. (Op.cit, pp. 15-16)