Phenomenological Issues

It's a mistake to look for metaphysical 'grounds' for theorising in general, since there isn't any relevant way of distinguishing metaphysical hypotheses from other kinds. Our capacity to form hypotheses - our capacity to talk about the world - isn't rendered more intelligible by the generation of further hypotheses of the same kind as those which we are trying to illuminate.

Our capacity to talk cannot, itself, by rendered hypothetical. Therefore, realism may only be a consequence of the possibility of language: it certainly can't underpin it.

Most of us think of our internal experience - our phenomenological states - as contributing to our ability to speak: we can talk about the world because we sense it, and we have a direct experience of what these sensations are.

Cases of sensory deprivation leading to specific linguistic incompetence support this: blind people cannot identify colours, nor deaf people sounds.

But we need to separate two things here:

(1) What we say about our internal states.
(2) The internal states 'in themselves'.

We can clearly talk about our internal states. However, we can only talk about them as represented in language.

I can say 'I see a bright light', but I cannot independently identify my seeing of a bright light except by making this statement (or one equivalent). The condition of seeing a bright light is irreducibly intentional.

Also, this is a public, not a private condition to be in: we can have an argument about whether I really did see a white light - or whether I made a mistake, or am telling a lie. This is true of the most primitive sensory reports - even those which look like candidates for 'sense data'.

Error and deceit are features of the reporting stage, however: I can't be mistaken or dishonest about my internal experiences in themselves. I also can't share them 'in themselves'. (There's even something metaphorical and indirect about this way of talking.)

The states 'in themselves' are beetles in boxes (PI 293). We all have them, but they only come into theoretical focus, or even appear to be shared, when we talk about them. This is why 'consciousness' in this sense can never be the subject of scientific enquiry: it stands just outside the realm of any possible articulated enquiry.

The apparent link between these phenomenological processes and being able to speak - knowing the truth about the world by being acquainted with it through sensation - is, itself, a phenomenological intuition. We might as well say about it that it is our internal experience of our capacity to speak. This is such a disturbing thought that many people find it impossible to entertain, but it becomes obvious after a little reflection: my only incontrovertable grounds for thinking you might have the same intuitions as I have are found in what you say about them.

You might say that I have grounds in your behaviour, but these are not incontrovertible - for Kripkean (Rules and Private Language) reasons. The interpretation of behaviour is always corrigible, but you can only doubt what I say about my phenomenological states by doubting my linguistic competency or my honesty. In both cases, you are doubting whether we are, in fact, conversing in good faith - you are doubting whether we are really talking.