 Thirdly, the production of outcome F by system S must involve a mechanism with internal components (vehicles) that stand in exploitable relations to environmental features. In many cases, the exploitable relations in question are informational: the mechanism’s internal components carry correlational information about the presence of certain features in the environment (Shea 2018,  ch. 4).[16]   In other cases, the exploitable relations are relations of structural correspondence: the mechanism’s internal components stand in relations to each other that ‘mirror’ relations between entities in the external world (Shea 2018, ch. 5). Furthermore, there may still be other types of exploitable relations. This pluralism about the relations that are constitutive of representational content is one of the reasons why Shea names his approach “varitel semantics” (Shea 2018, 43). 