<philosophy of mind> 1. See functionalism 1, the view that the physical realisation of a functional component is not, in some sense, its essence. Rather, what makes a functional component the type it is, is characterised in terms of its role in relating inputs to outputs and its relations to other functional components.
See multiple realisability, Turing machine, causal functionalism.
2. See functionalism 2 an explanatory approach to behaviour and the constitution of cognitive states that regards particular behaviours and cognitive structures and capacities as playing functional roles in particular domains or contexts.
Chris Eliasmith - [Dictionary of Philosophy of Mind] Homepage
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