Putnam: “Brains and Behaviour”
Putnam sets out his functionalist manifesto by attacking the three prior alternatives: dualism, materialism and (logical) behaviourism. Functionalism is the doctrine that mental states are differentiated by what they do and not by what they are made of. Putnam takes it as read that behaviourism, and its motivations, have done enough to show that the first two options are unsatisfactory. This leads him to focus on challenging behaviourism in order to clear the way for his functionalist alternative.
The challenge to logical behaviourism starts from Wittgenstein-type points around the impossibility of private languages in the ‘beetle in the box’ variant. There can be no security, on this line, that my pain and Jones’s pain or my pain at different times, are type-identical or even similar. So I cannot learn `pain’ or other mental words by ostension. How then do I know the intension of `pain’, and what is it?
Correlations between pain and `pain-behaviour’ are unreliable and in any case, a correlation is not a definition. Similarly, even if some brain events cause pain behaviour, the brain events are not identical with pain behaviour or pain. There is an analogy between mind words and disease names, in that while diseases normally but not invariably produce a characteristic set of symptoms, the existence of pain may normally but not invariably produce a characteristic set of behaviours.
What if super-Spartans were possible who could suppress all external expression of pain-behaviour?
We cannot do that, but this shows nothing about other possible worlds. Do these super-Spartans still feel pain? If so, then behaviourism is false, since there is pain which does not ever, let alone normally, issue in behaviour. Therefore pain is not translatable into pain behaviour.