Language and Experience: Evidence from the Blind Child

"This is another book about the acquisition of language by young kids who have some kind of sensory input issue. My own work tends to be on adult speakers of different spoken languages, so you’re probably wondering why I’ve chosen these two books about children. It’s because they both address really deep, almost philosophical, questions. Where does knowledge of language come from when you can’t hear it? That’s the question Susan Goldin-Meadow is asking in her book. Landau and Gleitman’s book, Language and Experience , I read first when I was a student, a long, long time ago. I’d read some philosophy , and learned that at one point John Locke raised a question in a letter to another philosopher: ‘What kinds of meanings of words, connected to sight, would a blind person have?’ They were interested in how much you know from experience, because Locke had this notion that everything in your mind comes through experience. I don’t know if this book goes against Locke or not, but it raises the fascinating question: how do kids learn which words connect with which meanings? What Landau and Gleitman did was they looked at blind kids’ knowledge of the meanings of words connected to sight. Since they don’t have sight, how much knowledge of the meanings of words connected to that sense—words like ‘see’ or ‘look’ or colour words—do they have? It’s raising the same interesting question: how do we have knowledge of language? Where does it come from? “I have strong opinions, but my interactions with people, even on Twitter, are pretty respectful in both directions, I think” And what they showed in that book is very different from Susan Goldin-Meadow’s book in some ways, but very similar in others. What they showed is that blind kids have an understanding of aspects of word meanings to do with sight that they don’t seem to have any obvious evidence for, in terms of their experience. They argue in the book that it’s the language that surrounds those kids that gives them some inkling, some understanding, of what those kinds of words like ‘see’ or ‘look’ or colour words, end up meaning. But they also say it can’t just be the language that does this. There must be more than that. There needs to be some kind of predisposition to go in certain directions and not others. For example, they talk about one child acquiring the meaning of the word ‘to look’—and understanding what it means not just for her, but also for other people. She ends up figuring out that ‘to look at something’ means that the thing can be at a distance, but it needs to be in the line of sight of the person who’s looking. There can’t be a barrier in between. She understands all that ‘to look’ means. Since she isn’t observing any of this, where does she get that information from? And why is it that precise information that she gets? They argue she picks some of it up from language—from what she hears being used around her in a very particular way. Grammar is key to that. This is an argument that the grammar of language is a way of ascertaining knowledge of its meaning, which is really fascinating. The other thing the authors argue is that this child needs some kind of internal predisposition to make those generalizations about the word ‘look’ as opposed to other ones. What the child does is she learns what ‘look’ means for sighted people, but when someone asks her to look at something, she will look at it with her hands. If you said to her, ‘Look at this cup,’ she would take a cup and feel it all over, to get a sense of what it is. She’s transferred the visual modality into a tactile modality, but the gaining of information through this particular sense still has the same kind of meaning. I remember reading the book when I was much younger, and it was a weird revelation. It seems obvious to me now, but when we learn meanings, we learn them not just from the word plus its environment, but from the word and all the other words around it and how we use them in sentences. They all feed back into each other in a really complex way, and that partly gives us the meanings of words. That’s not obvious, but this book really shows you that that had to be the case, that actually part of our knowledge of meaning, even in situations where we have no evidence of the thing sensually or experientially, has to come from the grammar of the language itself. These kids don’t see colours, and when they’re really young they use colours randomly. They’ll say, this is a green card, this is a red card and this is a blue card, even though they have no idea and they get it wrong. But they know that colour words are adjectives, that they modify nouns and they end up knowing things about them which are really interesting. So in the book they did an experiment where they gave kids objects. They tell them that the objects have certain colours and those colours always correlate with some other aspect of the objects. So, for example, all the big objects might be red and all the rough ones might be blue and all the small ones might be green. Then they see whether the kids naturally get the meaning of ‘red,’ ‘blue’ and ‘green’ to be ‘large’, ‘rough’ and ‘small’ and they don’t. They totally know that colour is independent of those other aspects of the object. That’s really intriguing, isn’t it? So they don’t know colours, but they know things can be coloured, and the fact that colour is different from other properties—even though they don’t have any evidence of that. They have evidence that all the big things are red, but then they know that red and size are different things. They end up having quite a rich knowledge of the meaning of colour words. So that’s the same thing again. Landau and Gleitman say it’s partly the language that you hear these words being used in and it’s partly what our human brains do with that language that ends up giving you a certain amount of information about something that you otherwise have no sensory information about whatsoever."