Field of Science

Learning What Not to Say

A troubling fact about language is that words can be used in more than one way. For instance, I can throw a ball, I can throw a party, and I can throw a party that is also a ball.

These cats are having a ball.

The Causative Alternation

Sometimes the relationship between different uses of a word is completely arbitrary. If there's any relationship between the different meanings of ball, most people don't know it. But sometimes there are straightforward, predictable relationships. For instance, consider:

John broke the vase.
The vase broke.

Mary rolled the ball.
The ball rolled.

This is the famous causative alternation. Some verbs can be used with only a subject (The vase broke. The ball rolled) or with a subject and an object (John broke the vase. Mary rolled the ball). The relationship is highly systematic. When there is both a subject and an object, the subject has done something that changed the object. When there is only a subject, it is the subject that undergoes the change. Not all verbs work this way:

Sally ate some soup.
Some soup ate.

Notice that Some soup ate doesn't mean that some soup was eaten, but rather has to mean nonsensically that it was the soup doing the eating. Some verbs simply have no meaning at all without an object:

Bill threw the ball.
*The ball threw.

In this case, The ball threw doesn't appear to mean anything, nonsensical or otherwise (signified by the *). Try:

*John laughed Bill.
Bill laughed.

Here, laughed can only appear with a subject and no object.

The dative alternation

Another famous alternation is the dative alternation:

John gave a book to Mary.
John gave Mary a book.

Mary rolled the ball to John.
Mary rolled John the ball.

Once again, not all verbs allow this alternation:

John donated a book to the library.
*John donated the library a book.

(Some people actually think John donated the library a book sounds OK. That's all right. There is dialectical variation. But for everyone there are verbs that won't alternate.)

The developmental problem

These alternations present a problem for theory: how do children learn which verbs can be used in which forms? A kid who learns that all verbs that appear with both subjects and objects can appear with only subjects is going to sound funny. But so is the kid who thinks verbs can only take one form.
The trick is learning what not to say

One naive theory is that kids are very conservative. They only use verbs in constructions that they've heard. So until they hear "The vase broke," they don't think that break can appear in that construction. The problem with this theory is that lots of verbs are so rare that it's possible that (a) the verb can be used in both constructions, but (b) you'll never hear it used in both.

Another possibility is that kids are wildly optimistic about verb alternations and assume any verb can appear in any form unless told otherwise. There are two problems with this. The first is that kids are rarely corrected when they say something wrong. But perhaps you could just assume that, after a certain amount of time, if you haven't heard e.g. The ball threw then threw can't be used without an object. The problem with that is, again, that some verbs are so rare that you'll only hear them a few times in your life. By the time you've heard that verb enough to know for sure it doesn't appear in a particular construction, you'll be dead.

The verb class hypothesis

In the late 1980s, building on previous work, Steven Pinker suggested a solution to this problem. Essentially, there are certain types of verbs which, in theory, could participate in a given alternation. Verbs involving caused changes (break, eat, laugh) in theory can participate in the causative alternation, and verbs involving transfer of possession (roll, donate) in theory can participate in the dative alternation, and this knowledge is probably innate. What a child has to learn is which verbs do participate in the dative alternation.

For reasons described above, this can't be done one verb at a time. And this is where the exciting part of the theory comes in. Pinker (building very heavily on work by Ray Jackendoff and others) argues that verbs have core aspects of their meaning and some extra stuff. For instance, break, crack, crash, rend, shatter, smash, splinter and tear all describe something being caused to fall to pieces. What varies between the verbs is the exact manner in which this happens. Jackendoff and others argues that the shared meaning is what is important to grammar, whereas the manner of falling to pieces was extra information which, while important, is not grammatically central.

Pinker's hypothesis was that verb alternations make use of this core meaning, not the "extra" meaning. From the perspective of the alternation, then, break, crack, crash, rend, shatter, smash, splinter and tear are all the same verb. So children are not learning whether break alternates, they learn whether the whole class of verbs alternate. Since there are many fewer classes than than there are verbs (my favorite compendium VerbNet has only about 270), the fact that some verbs are very rare isn't that important. If you know what class it belongs to, as long as the class itself is common enough, you're golden.

Testing the theory

This particular theory has not been tested as much as one might expect, partly because it is hard to test. It is rather trivial to show that verbs do or don't participate in alternations as a class, partly because that's how verb classes are often defined (that's how VerbNet does it). Moreover, various folks (like Stefanowitsch, 2008) argue that although speakers might notice the verb classes, that doesn't prove that people actually do use those verb classes to learn which verbs alternate and which do not.

The best test, then, is it teach people -- particularly young children -- new verbs that either belong to a class that does alternate or to a class that does not and see if they think those new verbs should or should not alternate. Very few such studies have been done.

Around the same time Pinker's seminal Language and Cognition came out in 1989, which outlines the theory I described above, a research team led by his student Jess Gropen (Gropen, Pinker, Hollander, Golberg and Wilson, 1989) published a study of the dative alternation. They taught children new verbs of transfer (such as "moop," which meant to move an object to someone using a scoop), which in theory could undergo the dative alternation. The question they asked was whether kids would be more likely to use those verbs in the alternation if the verbs were monosyllabic (moop) or bisyllabic (orgulate). They were more likely to do so for the monosyllabic verbs, and in fact in English monosyllabic verbs are more likely to alternate. This issue of how many syllables the verb has did come up in Language and Cognition, but it wasn't -- at least to me -- the most compelling part of the story (which is why I left it out of the discussion so far!).

Ambridge, Pine and Rowland (2011)

Ben Ambridge, Julian Pine and Caroline Rowland of the University of Liverpool have a new study in press which is the only study to have directly tested whether verb meaning really does guide which constructions a child thinks a given verb can be used in, at least to the best of my knowledge -- and apparently to theirs, since they don't cite anyone else. (I've since learned that Brooks and Tomasello, 1999, might be relevant, but the details are sufficiently complicated and the paper sufficiently long that I'm not yet sure.)

They taught children two novel verbs, one of which should belong to a verb class that participates in the causative alternation (a manner of motion verb: bounce, move, twist, rotate, float) and one of which should not (an emotional expression: smile, laugh, giggle). Just to prove to you that these classes exist, compare:

John bounced/moved/twisted/rotated/floated the ball.

The ball bounced/moved/twisted/rotated/floated.

*John smiled/laughed/giggled Sally.
Sally smiled/laughed/giggled.

Two groups of children (5-6 years old and 9-10 years old) were taught both types of verbs with subjects only. After a lot of training, they were shown new sentences with the verbs and asked to rate how good the sentences were. In the case of the manner of motion verb, they liked the sentences whether the verb had an subject and an object or if the verb had only a subject. That is, they thought the verb participated in the causative alternation. For the emotion expression verb, however, they thought it sounded good with a subject only; when it had both a subject and an object, they thought it did not sound good. This was true both for the older kids and the younger kids.

This is, I think, a pretty nice confirmation of Pinker's theory. Interestingly, Ambridge and colleagues think that Pinker is nonetheless wrong, but based on other considerations. Partly, our difference of opinion comes from the fact that we interpret Pinker's theory differently. I think I'm right, but that's a topic for another post. Also, there is some disagreement about a related phenomenon (entrenchment), but that, too, is a long post, and the present post is long enough.

Gropen, J., Pinker, S., Hollander, M., Goldberg, R., and Wilson, R. (1989). The Learnability and Acquisition of the Dative Alternation in English Language, 65 (2) DOI: 10.2307/415332

Ben Ambridge, Julian M. Pine, and Caroline F. Rowland (2011). Children use verb semantics to retreat from overgeneralization errors Cognitive Linguistics

For picture credits, look here and here.


Bob Carpenter said...

Does anyone now or did anyone ever believe that syntactic alternations weren't tied to the meaning of a verb? It's even called "causative", which is a semantic notion.

A quick search on Google Books turned up John Seely Hart's 1873 "Hart's English Grammar", which says on page 195, "In most languages there is a class of verbs derived from others and called causatives. If the original verb expresses any particular action the causative denotes the causing of that action. This practice is not wholly unknown to the English."

GamesWithWords said...

I don't think anyone denies that the transitive version of a transitive/intransitive alternator involves some kind of causation. But I suspect the claim that the semantics of verbs determines whether they alternate is a minority position.

I won't claim to pay careful attention to this literature, but very few of the studies I do come across even mention any role of semantics. Ben Ambridge is the notable exception, and he's told me he's encountered a lot of resistance to the idea (though personally I think it was conclusively proven to be true -- at least in part -- decades ago).