Tuesday, August 13, 2013

a verb class only a cognitive semanticist could love

Continuing my walk down dissertation memory lane (walk #1 here), this time I revisit the semantics of barrier verbs (and I remind you that this is largely a cut and paste job from my draft chapter on semantics).

Here is my set of "core" barrier verbs (I'll explain later how I distinguish between core members of a verb class and peripheral members as this was a topic of great interest to me).

ban, bar, barricade, block, deflect, detain, discourage, enjoin, exclude, exempt, guard, hamper, hinder, interrupt, obstruct, protect, pre-empt, prevent, prohibit, restrain, restrict, screen, shield, thwart

Note that neither stop nor keep are in the core set, yet either can easily be coerced into the barrier verb class. A keen spidey sense for semantics might also alert you to the fact that there are two sub-classes within that list: protect versus prevent. Oh, sooo much to discuss there. Too much for now, but yes, semantic madness lies that way.

My linguistics dissertation grew out of work by Len Talmy, so I’ll begin with a brief overview of his work on these verbs. Len wrote a 40 page monograph on this verb class and I may in fact possess the only extant copy. I really should scan that. I'll show in a later post how this semantic description impacts the syntactic construction that barrier verbs often occur in, as well as how the semantics impacts some quirky frequency facts. But for now, on with cognitive semantics!

The class of English barrier verbs are causative object control verbs* which encode the relationships between a goal directed participant (or “agonist” in Len's terms), its goal and a barrier participant (or “antagonist”). Situations involving barriers are more nuanced than simply one thing being in-between two other things. A barrier necessarily impedes the motion of one of the things it is in-between. Barrier situations require motion as well. However, we will see that this motion can be extended metaphorically to intentions and goals if not many other things. If an entity wants to achieve a certain outcome, yet is impeded by some force, this situation can be encoded by a barrier verb. Some examples:

Physical Blocking 
The fence blocked the car from entering the driveway

Intentional Exclusion 
The club excluded me from membership

Speech Act Pronouncement 
The judge banned journalists from the courtroom

Spybot protected my computer from a virus.

In the examples above, there is an explicit goal directed agonist (the car, me, journalists, a virus) and a goal (the driveway, membership, the courtroom, my computer). Only in the first sentence is there a physical barrier (the fence). In the other sentences there is an implied barrier (the club’s power to exclude, the judge’s ban, Spybot). But in all cases, the barrier interferes with the goal-directed agonist's ability to achieve its intended outcome.

But interference alone is not enough to properly distinguish a barrier situation from a simple in-the path situation that a verb like place evokes in a sentence like this one:

John placed the table between Chris and the kitchen. 

In this case, to place does not necessarily evoke the notion of interfering with goal-directed motion. One would have to infer (perhaps via Gricean maxims) that Chris wants to enter the kitchen in order derive a barrier interpretation of this sentence. But that notion is not entailed by the verb place, it is at best added via inference. A member of the barrier verb class should entail the notion that the agonist is goal directed (via motion or metaphorical extensions of motion). Therefore, the two end points must have a particular relationship to each another. Namely, one end point participant must be moving towards the other, or have some sort of tendency towards the other end point (this use of tendency is adapted from Talmy).

Talmy assumes a model of barrier dynamics in which there are three salient participants: A GOAL-directed Agonist X, a barrier-forming Antagonist Y, and a GOAL Z. Figure 1 (Talmy loves figures) represents this state of affairs where the arrow represents the X participant’s tendency towards the Z participant.

Talmy also recognizes the potential for the inclusion of a SOURCE entity as well (“an object at which the Agonist begins its path” (unpublished manuscript: 2), but it is only these three salient X, Y, Z entities which form the necessary basic structure of barrier dynamics.

Note that the inclusion of a GOAL distinguishes this set of situations from simple impeded motion, lexicalized in such English verbs as “stop”:
  • I stopped the lawnmower.
  • The judge banned journalists.
In the first case, the lawnmower is not encoded with any inherent GOAL by virtue of the meaning of stop. This could simply mean that the lawnmower was turned off. Note, however that adding a complement with the preposition from adds the notion of GOAL:
  • I stopped the lawnmower from destroying the flowers.
Above,  the verb ban encodes journalists with an inherent GOAL (presumably the judge’s courtroom as it would be pragmatically odd for a judge to ban journalists from her kitchen). Is this inherent tendency towards a goal a presupposition or invited inference or semantic entailment? Those arguments must wait for later.

What's crucial is that this tendency toward a GOAL is part of what constitutes the barrier situation and hence acts as a distinguishing feature which separates these verbs from other stopped-motion verbs like stop.

It is important to recognize that this set of situations is not just a possible set of events in the world but is actually lexicalized in certain English verbs, forming a natural class (there are cognate classes in Dutch and German and probably other languages). Identifying the properties of the verbs in this class (particularly with respect to the prepositions from and against) will require empirical, corpus based methods that will be the subject of later posts.

But what will really blow your mind is when I post about the difference betwen these two sentences:
Chris kept the dogs barking.
Chris kept the dogs from barking.
Chew on that for awhile.

*Maybe. I recognize that calling a verb a causative object control verb requires you to believe in such things as causative object control verbs, and some do not. There's really no escaping at least some theoretical stipulations.

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