So let’s talk about signs. When you see a new sign, you have to figure out what it
means if you want to follow it. The same thing happens when you run into a word that you’ve
never seen before - you just have to work out what it does. Every one of us takes up new words
all the time, from infancy onwards, but how do we actually learn what those words mean?
I’m Moti Lieberman, and this is the Ling Space.
So all of us have tons and tons of words in our heads, in one language or across many.
We rarely think about our individual words when we’re trying to say them - they’re just
there in our heads, ready for us to express our thoughts. But at some point, each and
every one of those words had to be learned.
This situation is made more complicated by the fact that the words that we use for things
don’t usually have anything to do with the things themselves, except for onomatopoeia
like plop or achoo. Like, there’s nothing particularly wall-like about the word “wall”,
or pie-ish about pies. This concept is often called the Arbitrariness
of the Linguistic Sign, and the groundbreaking linguist Ferdinand de Saussure came up with
it a century ago.
The sounds of words just aren’t predictable based on the information that we have about the
world. That information needs to be stored somewhere.
But where? Well, we can imagine that we have a kind of mental dictionary in our brains, where we keep all
information about words. We call these mental files a Lexical Entry,
and it contains everything you need to know about a word: how it's pronounced, where it goes, and
what it means. Let’s look at an example.
The Lexical Entry for the word “hound” tells you that it’s a noun that's pronounced like [hawnd],
and it means “large domesticated canine”. So for every language you speak, you fill up
your brain with tens of thousands of these lexical entries. But how do you manage to
build that dictionary up? Learning words is complicated! And in the real world, words
are flying at you like a flock of ravens.
The first thing you have to do is separate that stream of language into
its component parts. And that’s hard enough, but even when you do have
those little chunks, your job’s not over. You still need to map those phonological forms onto
their meanings. But if meanings aren’t predictable from
the sounds, then how do you even do that?
Here’s a concrete example, based on the work of philosopher W.V.O. Quine. So let’s
say you just happen to be standing around with a friend of yours, and a rabbit runs
by. Your friend points at the rabbit and says, “Hodor!” What does hodor mean? Well, maybe
it means rabbit. That’s a decent assumption. But if you think about it a minute, it could
also mean “run”, or “fast”, or “dinner”, or “look over there”.
There’s a huge list of things that hodor could mean. But you probably thought that
it meant “rabbit”, right? Well, fortunately, that’s one of the basic
assumptions that pretty much everyone makes, so it’s a natural guess.
Linguists have figured out four easy tricks that people use to associate arbitrary sounds and symbols
to meanings in the real world.
The first of these guidelines is known as the Whole Object Assumption. Now, this says that every
new word that you encounter will probably refer to the whole object, and not one of its parts
or attributes. So hodor should mean rabbit, not just the rabbit’s foot, or fluffy.
We’ve also got the Type Assumption. This means that a new word refers to a type of
thing, and not to any particular thing. So your friend pointing and saying hodor probably
doesn’t mean, “Look, there’s my pet rabbit, Hodor!”
So linguists ran an experiment on 4 and 5 year olds, to test the Type Assumption.
They showed them a picture of a cow, and said, “This is a dax. Can you find another dax?”
And then they showed them two other pictures: one of a pig, and one of milk. Now cows and pigs go together
by type, like if “dax” meant “barnyard animal” or something. Cows and milk aren’t
related by type - there’s a theme there, but nothing else. So what did kids pick?
Well, those kids that were told that the cow was a dax picked the pig 65% of
the time. So they definitely were preferring to interpret by type! But interestingly,
when they weren’t given a new label for things, and they just got shown the cow and then told something like,
“look at this, now can you find another one?” Kids only picked the pigs a quarter of the time.
So they were really using that label to help them group things together.
Another arrow we have in our word-learning quiver is the Basic Level Assumption. The
idea here is that some categories are more fundamental than others. So, a word like
“rabbit” is a basic-level category, whereas words like “mammal” or “animal” are higher
level categories. We usually assume that a new word will apply to a basic-level idea:
so hodor probably doesn’t mean “mammal”.
We’ve got one more weapon when it comes to picking up new words.
Let’s say you managed to learn that hodor really did mean rabbit. But the next day
you run into your friend again, and he’s holding his new pet rabbit, and he says something different,
like… bodor. Now, will you think that bodor means rabbit? Not if you follow the Mutual Exclusivity
Assumption. This says that objects have just one label.
So maybe bodor means something like soft, or fluffy, or it could be the rabbit's name, but it won’t just mean rabbit.
So let's look at an example. Imagine an experiment where kids get shown
two things - like, a tree, and then a shiny, funky new object they’ve never
seen before. Then you ask them, “Show me the zib”. They’re not going to point at the tree,
because they already know that trees are trees.
They nearly always assign the new label to the new object, because they assume that terms
are mutually exclusive. This is so powerful that it can actually override the other assumptions,
which we’ll talk about back on our website. Okay. So that’s the big stuff. But there are
a few other things that we can use if those four assumptions don’t give us all the information we need.
For example, we can use the information we already have about syntax and morphology for our language.
So, for example, we already know that -s usually gets stuck on nouns to make them plural,
or that common nouns can get preceded by determiners, like ‘a’ or ‘the’.
We’ve got some cool experiments about this, too. So researchers showed some kids who were
about a year and a half old some dolls. And the two dolls looked similar, but they only
talked about one of them, making the other doll really jealous. For some of the kids, they said “This is a zav”,
with the determiner stuck in there. Other kids were just told “This is Zav”,
without the ‘a’. After a while of this, researchers asked the kid to put some dress-up
clothes on the doll.
If they’d been hearing “This is Zav”, then they were asked to dress Zav, and they only
went to dress that one particular doll. But if they’d been hearing “a zav” the
whole time, then they were asked to dress “a zav”, and then they would dress either that one
doll or the other one. Both of them were okay, because they'd been using that little ‘a’ the whole time.
Little kids who weren’t even two and had never studied any grammar already knew that proper
nouns refer to one individual and don’t take ‘a’, whereas common nouns refer to a
type of thing, and do.
Before we wrap up, let’s go back to our idea about lexical entries. We already said that they
have information about pronunciation and meaning in them, as well as whether they’re a noun or a
verb or whatever. But now we can add some more information. Lexical entries include
facts about what situations a word can show up in. Like, is a morpheme free to stand
on its own, or does it have to get bound to something in order to show up? Does it need to have a
determiner like ‘a’, or not? Stuff like that.
Oh, and then, you have to wonder about plurals. Like, do you have two separate lexical entries
for “spear” and “spears”? Or do you have just one?
Well, the kind of plurals that you make just by adding an -s use a rule that people store in
their heads, even little kids. Remember the Wug Test, that we talked about back in episode 21?
You show a kid a drawing of some unfamiliar
critter and tell them it’s a wug. Then, you show them two of them, and ask them what they're called.
Kids will usually say two wugs, with the -s, even though they never heard the word wug
before. So this means that plurals, along with a whole bunch of other things, are stored separately in our
brains from the mental dictionary. We don’t need multiple lexical entries for spear and
spears, or for dragon and dragons. We only have the one, and our rules take care of the rest.
So even if Hodor is causing you some problems, you can use these assumptions to work
out what your friend is trying to get across. You build your mental dictionary using these
strategies, and you solve the problem of what meanings go where without ever even really thinking
about it much. That’s just another sign of how well our minds are built for language.
So we’ve reached the end of the Ling Space for this week.
If you assigned the right meanings to my sounds, you learned that what words refer to
isn’t as obvious as you might think; that we construct our mental dictionaries
out of lexical entries with information about pronunciation, usage, and meaning; that we
use four assumptions to help us guide our task: Whole Object, Type, Basic Level, and Mutual Exclusivity;
and that things that are driven by rules sit outside the lexical entries for the words
themselves.
The Ling Space is produced by me, Moti Lieberman. It’s directed by Adèle-Elise Prévost,
and it’s written by both of us. Our editor is Georges Coulombe, our production assistant
is Stephan Hurtubise, our music and sound design is by Shane Turner, and our graphics
team is atelierMUSE.
We’re down in the comments below, or you can bring the discussion back over to our
website, where we have some extra material on this topic. Check us out on Tumblr, Twitter
and Facebook, and if you want to keep expanding your own personal Ling Space, please subscribe.
And we’ll see you next Wednesday. Hodor!