Epistemology & Cognition Lab

Computational explanations in the cognitive sciences span multiple levels of analysis. The indeterminacy of computation complicates the endeavour of answering the question ‘What does a particular neural—or physical—system do?’ in computational terms. A single physical process may often be described equally well as computing several different mathematical functions—none of which is explanatorily privileged. But at which level of analysis is the computational identity of a physical system P fixed? Some argue that the computational identity of P is wholly exhausted by P’s functional or narrow physical structure. Others argue that contextual factors also play a role in determining P’s computational identity, but they diverge on what that role is precisely. Yet others argue that contextual factors essentially determine the identity of P. This chapter surveys some of these views and ultimately claims that the environment can and often does play an important role in fixing the computational identity of P, thereby proposing a new, long-arm functional strategy for individuating computation.