I recently posted a question on my Facebook page (Marianne Talbot Philosophy – come and join us!) which triggered a lot of discussion. This was the question:
Pillar boxes in the UK are red. So are strawberries and tomatoes. We can all agree on this. So we agree on what the word ‘red’ applies to.
But it is possible (logically at least) that when you and I look at UK pillar boxes, strawberries and tomatoes we have experiences with different quale. What does this tell us about the meaning of ‘red’?
I was immediately asked what ‘quale’ means. Good question.
‘Quale’ is the singular of ‘qualia’. Qualia are the ‘raw feels’ of experiential states. Experiential states are states of the sort that there is something it is like to have them. So having toothache, experiencing red, being in love or feeling jealous are all experiential states; there is something it is like to experience all of them.
Experiential states are distinguished from propositional attitudes.
Propositional attitudes are all attitudes to contents constituted of propositions (very roughly – meaningful sentences). So believing the chair is comfortable, intending to make a cup of coffee, or wanting to eat a marmite sandwich are all attitudes (of, respectively belief, intention and desire) to propositional contents (respectively ‘the chair is comfortable’, ‘I will make a cup of coffee’ and ‘I eat a marmite sandwich’)
All mental states involve some combination (or at least one) of these two state-types.
Experiential states are individuated by qualia – by what it is like to have them. (To ‘individuate’ a state is to classify it and distinguish it from other state-types.) Unless we are colour-blind we all know that what it is like to experience red differs markedly from what it is like to experience green. If we have ever been in love we know that it is common simultaneously to feel jealous. We also know that the former is a wonderful feeling, the latter is awful, and the combination is excruciating.
Qualia are central to the notion of consciousness. (So are propositional attitudes but perhaps not so obviously).
So my question was a way of asking whether the word ‘red’ refers to the quale we experience when we call pillar boxes, strawberries and tomatoes ‘red’.
The fact that we use the same colour-word for pillar boxes, strawberries and tomatoes suggests we believe them to be the same colour. (This is a rough classification – we all know that red shades into other colours – in answering philosophical questions we must resist red herrings).
The fact we recognize that we might all experience different qualia when looking at pillar boxes, strawberries and tomatoes tells us that the word ‘red’ cannot refer to the quale we experience when we look at pillar boxes, strawberries and tomatoes.
Think about it: we accept that these things are the same colour, and linguistically we act on this by applying to these things the same colour word – ‘red’. Yet we also accept that we might not experience the same quale when we look at these things. Perhaps when YOU look at pillar boxes, strawberries and tomatoes YOU experience what I experience when I look at grass, summer leaves and unripe tomatoes? (This may not be an empirical possibility, but it is certainly a logical possibility – it is another red herring to suggest this isn’t really possible).
So the colour word ‘red’ cannot apply to the quale.
Wittgenstein’s ‘private language argument’ deals with this problem. A quale is something intrinsically private. You cannot, even in principle, share your private conscious experiences with other people. I know what you are experiencing only through your language (or your other behavior). How can the word ‘red’, or indeed any other word, apply to something that cannot, even in principle, be known?
If ‘red’ applied to a quale it could not, even in principle, be taught. The teacher would never be able to tell whether or not the pupil was learning (because the pupil wouldn’t know for which quale the teacher was using the word, and the teacher couldn’t check the pupil was using it for the right quale).
If ‘red’ applied to a quale we could not, even in principle, communicate by means of it (because communication requires knowledge of same meaning and if ‘red referred to a quale we couldn’t know whether we meant the same by ‘red’).
So by ‘red’ we do not mean the experience we have when we look at pillar boxes, strawberries and tomatoes.
But we also don’t mean the wavelength of light reflected by an object – in the case of ‘red’ 650 nanometres. Can anyone tell me why?