Reduction Within Pragmatic and Cognitive Frameworks

Another obvious candidate to illuminate the relevant aspect that is responsible for the directionality is this The difference is cognitive and pragmatic in nature. This idea has been put forward, for example, by Robert Van Gulick in a series of papers (1992, 2001)  

From this characterization, that is offered with an eye on the pragmatic and epistemic success of reductions, we can easily derive a characterization of how we could reconcile diversity and directionality with unity a reduces to b expresses 

The assumption [that an explanatory asymmetry is sufficient to exclude identity] is false. Explanation is an epistemological endeavor. Identity is a metaphysical fact. It is entirely possible for two property descriptions cp and lt to refer to the same property in all possible worlds, and yet, since we may know that an object answers the description p antecedently, a new theory that shows the object to answer the description lt may succeed in telling us why the object answers the first description, or it may succeed in deepening our understanding of the fact that the object answers the first description. (En 1976,290) 

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