Setting Aside Certain Types of Change Of Meaning

I think when we talk about change of the meaning of the words, we need to differentiate two things. One is change that comes from knowledge about the correct use of the word, and the other is change of meaning that might come from the knowledge about whatever it is to which the word refers.

If two people don’t mean the same thing by the word because of misunderstanding of what the word is supposed to mean.

• If one of the parties in semantical disagreement is taken to be expert on what the word is supposed to mean, the disagreement is resolved by the expert correcting the wrong usage of the word of the other party. Such is the case I think with the children and their usage of words described in the previous post. The children being aware just that the things can show gestalt perceptual similarity, don’t have anything else to connect the word to. So to say, because they aren’t (at that time) aware of any other kinds of similarity between the things, they do their best with what they are aware of. But in this case adults are taken to be expert of the usage of the words, and through the years by explaining, pointing, describing children become aware of other kinds of similarities, and connected to that can correct their use of words. We can say that what is changing here is both the knowledge about the world, which  opens possibility for learning the correct use of the word.
• If none of the two parties considers the other one (or others) as an expert, either they will be pragmatic or they will end up fighting.

As Richard pointed in the comments of last post, if people can mean different things by the same word is not an issue. I acknowledge that point, and I think that nobody has (or should have) problem with change of meaning of words which is motivated by learning or by pragmatic decision about use of words, and which (I think) would cover the cases that appear in cognitive development.

So to make the issue which I raised in previous posts more specific – it is not just if there is possibility of change of meaning of the words, but if a change of the meaning of the word can happen among the competent users of the word, which are in same time also experts about what the word refers to.

More On Twin Earth and Change Of Meaning

In the post Phenomenology of Names and Twin Earth, I said that if one accepts the position that common nouns are based on awareness of multitude of things (real or assumed) which share some similarity, the consequence is that in the Twin Earth scenario, Oscar and Toscar mean same thing by “water” before they figure out that water is H2O, and that twater is XYZ. That is, because the similarity on which their words are grounded are shared across both water and twater.

In the comments of that post, I compared two scenarios to back up that claim:

Scenario 1:
1 – Martin sees a bunch of elm trees. He becomes aware of the gestalt similarity of this multitude and names those “trees”
2 – Later, on some other place, Martin sees beech trees and says – “Ah, there are more trees here”

Scenario 2:
1′ – Martin sees bunch of elm trees. He becomes aware of the gestalt similarity of this multitude and names those “trees”
1a’ – Martin further puts attention to the form of their leafs, branches, roots and so on. He gets more knowledge of the extension that he is acquainted with (and which he calls “trees”).
2′ – Later, on some other place, Martin sees beech trees. But in this case he notices the difference between beech trees, and what he called “trees”. So he says – “Ah, there are those things here that are similar to the trees, but those are not trees”.

If you find the second scenario sounds wrong to you, just change the word “trees” with the word “elms”. Nothing substantial changes, by changing the word that is used.
Both scenarios seem normal to me, but in the first scenario word “tree” ends up meaning tree, while in the second scenario “tree” ends up meaning elm. However everything is same in both scenarios, so there has to be some change of meanings which corresponds with the additional knowledge that Martin gained in second scenario in step 1a’.

Richard in the comments said that if the additional knowledge changes the meanings of the words, then communication is not possible. One can point here to two things:

1.
That it is a fact that this kind of differences of meaning appear in the conceptual development. Frank C. Keil in his book Concepts, Kinds and Cognitive Development does different tests of the development of different concepts in kids.
One example is where he asks children if some kind of transformation would change certain thing (animal, mineral, artifact) from one type to another. Here is an example of the story about tiger/lion “transformation”:

The doctors took a big tiger that looked like this. They used special fur bleach to take away its stripes, and they sewed on a huge mane so that it ended up looking like this. Was this animal after the operation a tiger or a lion?

The question was asked to children of different age, and the results were as in the following graph:

The X axis represents the kids’ grades K (5 to 6 year olds), 2 (7-8 year olds) and 4 (9 to 10 year olds). The Y axis represents the answers that were given, where 1 = judgment that transformation changed kind type, 2 = judgment indicating indecision on that issue and 3 = judgment that operation did not change kind type.

So, it seems that there is some change of what kids mean by “tiger” or “lion” through their development and I think that the graph goes nicely with the idea that first kids become aware of multitude of things that show gestalt perceptual similarity, and that only later they become aware of other kind of similarities that hold between certain multitudes. (This is surely a oversimplification, but I think it could be analyzed in more details if needed).

2.
But what to do with objections like Fodor’s from Thought and Language, when talking about possibility that children and adults might mean different things by the words, he says (citation also taken from Keil’s book):

They must misunderstand each other essentially; and, insofar as they appear to communicate, he appearances must be misleading. Nothing less than this is entailed by the view that word meanings evolve.

I want to point here, that as long as the two meanings (in the sense of awareness of some similarity) are grounded on the same extension, the communication might go without bigger problems, as in both cases it is finally the extension that one is aware of (i.e. the multiplicity). So to say, as long the things that show the gestalt perceptual similarity which is ground for the usage of the common noun of certain person (e.g. “tree” in the example) are the same things which show some other kind of similarity that is ground for the usage of the same word for another person, those two persons will agree in lot of cases on the use of the noun. For example Martin-scenario1(after 1) and Martin-scenario2 (after 1a’), would not have lot of problems of communication until such things as 2/2′ happens.