Go C-Command Yourself!

I have a puzzle for you: when would use him/her/them vs himself/herself/themselves? Can you ever swap one out for the other?

Got an answer in your head? Cool!

In this post, I hope to break whatever answer you came up with, and replace it with a surprising yet simple answer! You’ll laugh. You’ll cry. And maybe… just maybe, you’ll learn yourself something.

Definitions

First, let’s define some terms. For our purposes there are three types of noun phrases:

R-Expression

Referse to something specific or concrete.¹
i.e. “The cat”, “Tom”, “My hopes and dreams”

Pronoun

May (or may not) refere to another NP in the sentence (or discourse).
i.e. he/him, she/her, they/them

Anaphor²

Must refere to another NP in the sentence.
i.e. himself, herself, themselves

Here’s an example to make that a bit more concrete. We’ll use an index to mark what each NP could be referring to.

1. Jeremy fooled himself into thinking he could love another man.

Note how “he” could refer to Jeremy (likely how you read it without context), or it could refer to some other man, like Kyle!

2. Jeremy fooled himself into thinking Kyle could love another man.

It’s that flexibility that makes “he” a pronoun, and the lack of flexibility “himself” an anaphor.

The Puzzle

So, let me phrase our riddle a bit more exactly: what syntactic rule governs the distribution³ of pronouns and anaphora?

Indexing

First thing I want to point out that the index matters! While a pronoun can refer to multiple things, when actually used there is an intended meaning. For example…

3. Roberto taught himself to fly.
   Roberto taught him to fly.

Using “him” to refer to some \(j \not= i\) works just fine. However, if “him” means “Roberto”, things don’t work!

4. Roberto taught himself to fly.
   Roberto taught him to fly.

Word for word the sentences in (4) are the exact same sentences as (3). But these sentences syntactically cannot match with the semantics being expressed. If Roberto has taught himself to fly, “Roberto taught him to fly” just doesn’t communicate the right idea!

It’s also worth pointing out that duplicating the R-Expression is also unnatural:

5. Roberto taught Roberto to fly.
   Roberto taught Roberto to fly. (Two men named “Roberto”)

So, whatever rule we come up with, it’s going to have to keep the indices in mind!

Word Order

Ok, maybe you came up with a rule like this:

“If a noun follows another noun, and they share indices, an anaphor must be used.”

6. He taught Robert to fly.
   He taught Robert to fly.
   He taught himself to fly.

Seems reasonable, but it’s a little too simple. Remember (1)? This was a totally valid reading:

7. Jeremy fooled himself into thinking he could love another man.

He followed himself here, yet “Jeremy fooled himself into thinking himself could love another man” certainly didn’t work.⁴

“Ok… if the last noun was an R-Expression with the same index…”

8. [[Heidi]’s mother] bopped herself on the head with a zucchini.
   [[Heidi]’s mother] bopped herself on the head with a zucchini.
   [[Heidi]’s mother] bopped her on the head with a zucchini.
   [[Heidi]’s mother] bopped her on the head with a zucchini. (Carnie 2013, chap. 5)

Not bad, but what about this:

9. [The mother of [Heidi]] bopped herslef on the head with a zucchini.

In (9), Heidi was the most recent R-Expression! Whatever rule we come up with, we’re going to need a bit more structure…

Subject-Object Relationship

You might know anaphora as “reflexive-pronouns”, so maybe you gave a rule like

“If the object of a verb shares an index with the subject, an anaphor must be used. Otherwise, it can never be used.”

This is a pretty good rule, but unfortunately it under generates (meaning anaphora get used in more places than this rule would suggest). Consider:

10. She told me all about herself.

“About herself” is a prepositional phrase, not exactly an object! We’re close though… One thing that seems to be true — if an anaphor can be used, it must be used.

Alright, enough playing around, let’s take a more structured look at things!

C-Command

Our solution is going to be rooted in the tree structure of our sentences. Often with trees we use relationships like “parent”, “child”, “sibling”, “cousin”, etc… The relationship we need here is just a tad richer — c-command.

C-Command

(Informal) Node A c-commands its siblings and all of their decendents.
(Formal) Node A c-commands node B if every node branching dominating A also dominates B, and neither A nor B dominates the other.

To get a feel for this relationship, here is a very simple syntax tree⁵. Click on any node, and it will show which nodes that node c-commands!

In the formal definition I have to note that we calculate siblings from the first “branching” ancestor. For example, in the above sentence you might notice that “The” c-commands all nodes in the NP, even though it technically has no siblings. It’s like we skip-over D, and go strait to the NP root.

Now that we understand the c-command relationship, we should be able to come up with a solution to our puzzle!

Binding Principals

Let’s look at the tree for (8).

Now, we have a few notes we can make here:

• The NP “Heidi’s mother” c-commands the entire VP.
• The N “Heidi” doesn’t c-command the VP.
• “Herself” doesn’t c-command the subject phrase.

We can use this information to come up with a pretty good set of rules! First, to make our definitions a bit more clear, we should define the term “syntactic binding”.

Binding

A binds B if A c-commands B, and A and B share the same index.
We say A is the binder and B is the bindee.
If A is unbound, we call it free.

Now, finally, let’s look at our rules!

The Binding Principals

Anaphor: An Anaphor must be bound.
Pronoun: A pronoun must be free.
R-Expression: An R-Expression must be free.

Look back at our examples thus far, and see if they work out!

Binding Domain

These binding principals describe things fairly well, solving the problems we’ve seen thus far, but it needs one little revision! Let’s look back at our first example

11. Jeremy fooled himself into thinking he could love another man.

“Jeremy” is certainly free. “Himself” bound. But what about “he”? It looks like “he” could be bound, or not, yet “he” seems to be ok in both cases! To address this, we add one last idea — a binding domain. Because “he could love another man” is its own clause, we say “Jeremy” is outside the binding domain of “he”.

It’s as if, when choosing between “he” or “himself”, we only look at the tree for that clause:

In this subtree, “he” is free, even though it is bound outside of this clause.

At the same time, R-Expressions don’t seem to have this binding domain!

12. Jeremy fooled himself into thinking Jeremy could love another man.

With all of this, we can revise our answer, and come up with a final rule.

The Binding Principals (Revised)

Anaphor: An Anaphor must be bound in its binding domain.
Pronoun: A pronoun must be free in its binding domain.
R-Expression: An R-Expression must be globaly free.

That, my friends, is our answer!

Does this Cover Everything?

You may have found some examples which don’t seem to fit our definition. For example, sentences such as “she read the letter herself”. It turns out this isn’t as much of a problem, as this usage of”herself” is, in fact, acting as an adverb / focus particle, and not actually a noun phrase. In some languages, this focus particle would actually be a different word (“sie hat es selbst gelessen” and not “sie hat es sich gelessen”).

There are also some problems with our idea of binding domain, which muddies the waters a bit — clarifying it, however, would require some background in movement, which I don’t want to get into.

Conclusions

Early in my introduction to linguistics I learned about the c-command relationship, only being told it was “very important” (which I didn’t find to be particularly helpful). Binding, however, was when I realized it really was important!

Binding is a very well developed theory, and in fact Government and Binding Theory was an early form of The Minmalist Program (the current dominant theoretical program in Transformational Grammar). For an introduction to how binding operates in these frameworks, I’d recomend Chomsky (1980) (but be warned, this paper is very technical). Higginbotham (1980) gives a similar (and a bit more accessible) introduction to the idea, which only focuses on the uses we touched on here. While Higginbotham uses complex theories of movement, I think the paper is at least skimable to the beginner.

For a lighter introduction, I learned about binding from my first syntax book, Carnie (2013, chaps. 5, 17). For someone new to linguistics (which… if you just read this post, that’s probably you) I would strongly recommend that book.

Thanks for reading! Let me know if something didn’t makes sense! I’d be curious how these rules fit within your own languages!

References