The Brain as an Input-Output Model of the World

An underlying assumption in computational approaches in cognitive and brain sciences is that the nervous system is an input-output model of the world: Its input-output functions mirror certain relations in the target domains. I argue that the input-output modelling assumption plays distinct methodological and explanatory roles. Methodologically, input-output modelling serves to discover the computed function from environmental cues. Explanatorily, input-output modelling serves to account for the appropriateness of the computed function to the explanandum information-processing task. I compare very briefly the modelling explanation to mechanistic and optimality explanations, noting that in both cases the explanations can be seen as complementary rather than contrastive or competing.