Language Machines

What we actually say to one another is only philosophically interesting as a guide to what we can say to one another. And the limits of what we can say are not the limits of what we can think, from an internal, phenomenal perspective - although they do determine the limits of the thoughts we can attribute to one another. Further, the thoughts we can attribute to an interlocutor within the conversation we are having with him or her are more constrained than the thoughts we can attribute to someone with whom we are not having a conversation - or even cannot have a conversation. We can only incorrigibly attribute thoughts to an interlocutor (corrolary to Kripke).

I can say of someone 'he believes it is impossible to talk', but I cannot say to you 'you believe it is impossible to talk'. And 'I believe it is impossible to talk' directly undermines its own meaning, so must be false if it means anything. My attribution of this thought to someone is always corrigible, however.

We cannot attribute thoughts without attributing rule-following. (I think this is what Frege believed). And there are other reasons why rule following and intentionality go hand in hand. One is (again) to do with Kripke's paradox - we cannot define rule following in terms of behavioural descriptions which do not, themselves, refer to rules. This can be extended: we cannot define a rule in terms of the behaviour of any actual mechanical system. We cannot define 'or' in terms of the behaviour of some specific 'or' gate (a physical logical standard equivalent to the standard metre) without having some guarantee that the gate would never fail - and this guarantee obviously couldn't depend on the behaviour of some further physical system. What would count as failure is an irreducibly normative, and not simply a mechanical, issue.

To someone of a certain physicalist bent, this will sound wrong: after all, are we not, ourselves, physical sytems? How can we speak to one another if our speaking to one another requires the attribution of intentionality and rule following, while agreeing that rule following cannot be rendered physically?

This would be a reasonable question if it could be posed from outside our linguistic system (independently of all questioning and answering), but no quesiton can be posed from that standpoint. The most abstract, self-referential questions are still moves within the game. And if we cannot play the game without following rules then we must be able to follow rules - regardless of the clash with physicalist intuitions.

A more reductive, rather than reductio, response to the physicalist is to point out that physicalism can only be given substance by attributing rule based behaviour to 'nature', and this cannot be an outcome of grounded discovery. When we state a physical law we say that some things 'always' or 'everywhere' (given appropriate context) behave in some way (and, of course, the scope of any hypothetical law is itself, stated unconditionally: 'this only happens here' is not local even if 'this' is). Counterexamples, infamously, can be dealt with semantically as well as hypothetically. We discover and define as we go along - we find out a property, and then use it as a test (as in the boiling point of a liquid). We render the world intelligible by showing how it can be described - by discovering how we can talk about it, and, therefore, what thoughts about it we can attribute to interlocutors. (I might, as usual, add 'honest and competent' to 'interlocutor' except that these adjectives also directly determine the applicability of the descriptor - what would a dishonest and incompetent interlocutor look like?)

In other words, we can only construct the physicalist metaphor if we can talk to one another, and we can only do it by rendering the world in a way which appears, already, to contain semantic elements. This does not make it a bad metaphor, but it does make it an irreducible one - it can only ever be a heuristic, not an epistemological or metaphysical fundamental.

'We can talk about the world' is a fact about the world, but it cannot be given an 'account' of in terms of some other 'facts' that do not, already, depend upon it.

It is clear, in one sense, from all of this, that we can think of things that we cannot make. We cannot make a machine sufficiently reliable to be a standard for 'or', for instance; though we can know how 'or' works and, therefore, how such a machine should work if it could be constructed. Our best machines of this kind (the ones we can almost completely rely on) depend on aspects of our world that are most semantically secure. We would hardly know what physics was if we couldn't rely on the mechanisms from which our computers are built - and by this, I mean that we would regard someone who questioned these mechanisms as asking unintelligible questions. To have them break down would be like having an intelligent friend suddenly begin to talk nonsense. We could have no conversation with this friend within which we could explore the nature of the nonsense. To find some radical error in physics would be like finding that everyone had been talking nonsense - a discovery that could not be articulated, because there would be no language to articulate it with; a discovery that could not be scientifically demonstrated because the tools of demonstration themselves could not be relied on ...

In a way, our science says: 'If the world were a perfect machine which followed these (specified) rules, then it would behave in this way'. But the rules of this machine are explicit rules - rules which can be articulated. We cannot appeal, for their 'reliability', to some more metaphyscially fundamental machine, because the rules specifying this machine could not be written down in any language we could translate (and so in anything that we could recognise as a language at all). We can't make sense of the question 'what rules must I be following, in order to be able to follow a rule?', nor of the question 'what rules does the world follow so that we are able to securely describe it as following rules?'