The foundational text of Functionalism. It formally establishes the view that mental states are defined by their functional roles (what they do) rather than their physical composition like in the Mind-Brain Identity Theory.
Concerns the question ‘Is pain a brain state?’.
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[The statement]‘Light is invariantly correlated with electromagnetic radiation’ would leave open the questions ‘What is the light then, if it isn’t the same as the electromagnetic radiation? and ‘What makes the light accompany the electromagnetic radiation?’- questions which are excluded by saying that the light is the electromagnetic radiation. Similarly, the purpose of saying that pains are brain states is precisely to exclude from empirical meaningfulness the questions ‘What is the pain, then, if it isn’t the same as the brain state?’ and ‘What makes the pain accompany the brain state?’
Proposes the hypothesis that pain, or the state of being in pain, is a functional state of a whole organism, rather than a brain state or a behavior disposition. The brain operates like a “probabilistic automaton”. He argued that mental states are simply intermediate steps in a causal network. They take sensory inputs, interact with other internal states, and produce behavioral outputs, just like software running on computer hardware.
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“it seems more likely that the functional state we described is invariantly ‘correlated’ with pain, species-independently, than that there is either a physical-chemical state of the brain (must an organism have a brain to feel pain? perhaps some ganglia will do) or a behavior disposition so correlated.”
Points out that if an alien or an octopus experiences pain, their physical biology is entirely different from a human’s. Since they both act in pain, pain cannot be defined by a strictly human brain state. Instead, it is defined by its function (avoiding damage, desiring the pain to stop) and can be multiply realized in completely different physical materials.