Friday, October 19, 2007

Communication boards and indexicals (Language, Part I)

This is the first in what may be a series of posts developing a view of language that erases the distinction between language and context. The view may self-destruct before it's fully developed. I'm having fun here. No originality is claimed.

Some disabled people communicate with a communication board. A communication board is a board with printed pictures, some representing objects like shoes and chairs, some representing verbs like sitting, and some representing emotions like happy or sad. One communicates with a communication board by pointing to a sequence of pictures. High-tech communication boards will say the word, but it's important to my argument that I be talking of a low-tech one, which is just a pre-printed board. If a communication board is sufficiently large and extensive, and there is sufficient syntactic structure in the order in which one points to the pictures, this will be a language.

Let's say that the pointing is done with a finger. Now, what are the words or other linguistic units in this language?

Here is a really bad suggestion: The words are constituted by pointings with a finger and two token pointings count as of the same type if and only if the finger directions in the two pointings have the same relationship to the natural axes of the speaker's body (within some measure of precision; I will use the word "speaker" regardless of whether a language is spoken or not). The pictures on the board, on this suggestion, are simply context.

What's wrong with this suggestion? Well, for one, it means that if the speaker points to parent, fruit and happy, expressing (let's suppose) the proposition that the parent is happy with the fruit, and I shift the board over by an inch, and the speaker again points to parent, fruit and happy, then the speaker has used different word types, because her pointings are now in different directions. That is absurd--surely the speaker has said the same sentence.

Another way to see the absurdity of this view is that it will be impossible to give a story about the syntax of the language in terms of the arrangement of word types, since whether a given sequence of finger pointings, identified by direction relative to the speaker's body, is syntactically correct depends crucially on what the pictures pointed to are, and not just on the angles (again, think of a case where the board gets shifted over). But we don't want context to be the primary determiner of syntax!

One might think that the mistake in this story is that it is not the angles relative to the speaker body that matter for identifying the word type, but rather the direction of the finger as measured in some natural coordinate system based on the configuration of the board. (E.g., run the x-axis along the horizontal side of the board, the y-axis along the vertical side, the z-axis upward from the board, and then specify the cartesian coordinates of the tip of the finger and the finger's big joint.) But that's silly, too. Suppose that the speaker's board gets upgraded by getting a few new pictures, and with existing pictures moved a bit to accommodate the new ones. The speaker's language, thus, becomes extended. But now if we identified word types in terms of the coordinates of the finger relative to the board, the same sequence of finger positions as before would now be expressing something completely different. More seriously, previously syntactically correct sequences of word types would no longer be syntactically correct. In other words, we have a completely new language. But that is surely a hamfisted way of describing what happened in the board upgrade. There is something that is obviously wrong with the previous two accounts. The crucial thing to note is that the pictures that are pointed out are not mere context. They are crucial for the syntax: whether a sequence of three pointings is syntactically correct depends precisely on what parts of speech the pictures represent. Clearly, the thing to do is to either identify word-types with the pictures that are pointed out (more precisely: picture-types, in order to allow for upgrades of the board), or with pointings-at-x, where x ranges over the pictures (or picture-types) on the board.

Hypothesis: What happens with the communication board is also what happens with demonstratives. The thing pointed to is not context: it either is a part of the sentence (much as some folks think that items referred to de re are parts of the proposition) or a pointing at (de re) it is a part of the sentence. And something like this happens with all indexicals. At this point I am offering no argument, except the suggestive analogy of the communication board language.

Apparent disanalogy: In the communication board language, it is not the the picture tokens that function as word types (or, equivalently, it is not the pointings-at-picture-tokens), but the types of pictures (or the pointings at a type of picture). But in true demonstratives, there is no similar type/token distinction on the side of the things pointed out. One simply points at Alexander, not at something of the sort of Alexander.

This disanalogy is due to the fact that in a typical communication board, none of the pictures refer to the picture-token there, and that in typical demonstratives, we are trying to refer to particulars. But I submit that these are mere accidents. We could imagine that some of the pictures indicate particulars, like George, Socrates, etc. And there would be nothing absurd about a picture that indicates the picture-token that it is. (Maybe it's a very a beautiful and emotionally significant picture, so it's worth talking about as an individual. When a board is upgraded, it gets scraped off the old board and pasted on the new one.)

Moreover, we do in fact have cases where demonstratives point to a type, it's just that we don't use them quite as much as ones where we point to particulars. We've learned this from Kripke. Point to water and say: "We will call this 'water'." The "this" refers to the natural kind, not the particular bunch of water.


Paul M. Rodriguez said...

What about codes? Consider the board as being, rather than an integral object, a series of image-counters on the cells of a gridded table. The speaker is expecting two visitors, A and B. A has seen the board in its original state; B has not. The speaker wants to convey something secretly to A, so in advance of B's arrival he moves all the counters on the grid one cell over to the right. When he points, it seems like gibberish to B, and B judges it syntactically incorrect. But A recognizes it as a code, and judges it correct. The same could hold if another picture were added, and each image-counter shifted one position within certain margins. It seems to me that you overstate by implying that if the speaker points to a certain image, that he necessarily means to express that image. The syntactical correctness of what he indicates must be judged by what some particular hearer understands by it.

Alexander R Pruss said...

Yes, that's a nice point, there is no need for the board to work the standard way, and the added complication you give is helpful here (and I think may be helpful to the full view that I'm working on). So thanks!

But for my analogy with indexicals, I need the case where it works the standard way. :-)