# Government and Binding Theory/Case Theory

After having visited the complex approaches to bounding theory, we now dive into the weird and wonderful world that is Case Theory. GB theory has taken the concept of case from traditional grammar, and utilised it to explain many grammatical phenomena in syntax.
However, a distinction has to be made between morphological case, which is marked by inflection, and with abstract case. Morphological case is absent in English except in the cases of certain pronouns (I/me, who/whom, etc.). In other nominal expressions, it is not. Consider:
(1a) The dog bit him. (1b) The dog bit the boy.
In (1a), him is marked as accusative, but not the boy in (1b). Only the him has morphological case, but both have abstract case.

## Inherent and structural case

Firstly, we need to make sure we know what a Case is. Recall from our basic linguistics book that case is a grammatical property of a noun (now a DP) that usually correlates with the role of a verb in a sentence. Consider the French examples below:
(2a) Je le tue. (I him kill) (2b) Je lui obéis. (I him obey) (2c) Je parle de lui. (I talk about him.)
The Case of him in (2a) and (2b) depends here on the verb: tuer (accusative) and obéir (dative). Thus we can tell that it is the verb that determines Case here. In (2c), de also determines the disjunctive Case of lui. Thus prepositions can also assign Case.
In Case Theory, we also draw a distinction between inherent Case and structural Case. The former is determined by idiosyncratic properties of the verb. For example, in (2b) obéir assigned the dative Case to lui. The latter applies to all structural positions; for example, all verbs assign accusative Case to the object, direct or indirect. Inherent Case is assigned at D-structure; structural Case is assigned as S-structure.
* Inherent Case
* Inherent Case is assigned by α to a DP iff α θ-marks the DP.

## Assigning case
### Marking by inflection

Since inherent Case is dependent on θ-marking, little has to be said of its assignment. However, we still need to explore the assignment of structural case.
Let's look at nominal case. It does not depend on the idiosyncrasies of individual verbs, so it's a structural case. However, it is not always assigned to subjects:
(3a) I wanted him to finish his homework. (3b) It would be weird of me to do my homework.
In (3), him and me are clearly subjects, and yet they are accusative! What is going on? Note that both the clauses with me are non-finite, which means it is the finite inflection that assigns nominative Case. In (3a) and (3b), of and wanted assigned accusative Case instead.
Here is an example of nominative case assignment:
[DIAGRAM NEEDED]

### Marking by complementiser

Complementisers are also capable of assigning Case. Consider:
(4a) I wish for him to be able to find his parents.
Here, for is a complementiser for the IP him to be able to find his parents. As we have seen above, the non-finite clause does not assign nominative case to him; instead, this is handled by the complementiser for.

### m-command and government

So far, we have seen the following:
* Verbs and prepositions can assign Case to their complements (2)
* Verbs can assign Case to the subjects of their IP complements (3a)
* Complementisers can assign Case to the subject of their IP complements (4a)
* The finite inflection can assign Case to the subject
How can we explain these? Pro tem, we will ignore the second case and focus on the rest. The notion of government is central to GB theory, and it beautifully captures our first, third and fourth situations. Firstly, however, we need to take care of the concept of m-command.
* m-command
* α m-commands β iff:
* α does not dominate β,
* α does not dominate β, and
* the first maximal projection dominates α and β.
Next, we have to define what a governor, or an element that governs, is.
* Governor
* All lexical heads and the finite inflection are governors.
As for the formal definition of the government, this harks back to bounding theory, which we've seen last chapter. This is the usual definition of government:
* Government
* α governs β iff
* α is a governor,
* α m-commands β, and
* no barrier intervenes between α and β.
Under the relativised minimality version of bounding, the last line would be rewritten as 'there is no closer governor to β than α.

### Government in Case Theory

Now that we've laid out our framework, let's test-drive it on the three cases captured by government, to see how they explain case assignment.

#### Case 1: V and P to complements

* killed is a V, a lexical head.
* killed m-commands me:
** killed and me are sisters, so neither dominates the other.
** The first maximal projection of killed is the VP, which dominates me.
* There are no barriers between the V and DP (obviously, since there's nothing between them)
Thus killed assigns Case to me.

#### Case 2: Finite inflection to subject

* Ø is an I, a finite inflection.
* Ø m-commands I:
** I is the specifier and Ø is the head. Neither dominates the other.
** The first maximal projection of Ø is the IP, which dominates I.
* There are no barriers between the V and DP (again, obviously, since there's nothing between them)
Thus Ø assigns Case to I.

#### Case 3: C to specifier of IP

* for is an P (a prepositional complementiser), a lexical head.
* for m-commands me:
** me is dominated by IP, which is a sister of for. Neither dominates the other.
** The first maximal projection of for is the CP, which dominates me.
* There are no barriers between the C and the IP (IP is not a barrier)
Thus for assigns Case to me.

### Exceptional Case-Marking (ECM)

Most of the time, verbs, as we know them, cannot have IPs as complements; they must have complementisers to help the IP, well, become a complement. We have learnt this back in our introductory book on linguistics. Yet (3a) appears to defy this. Let's copy (3a) here to study it more closely:
(5a) I wanted him to finish his homework.
Could it be that there's an omitted complementiser, as in I think (that) he has done his homework? Let's try that:
(5b) *I wanted for him to finish his homework.
That (5b) is ungrammatical tells us a lot about this sentence, as we now know that want can take an IP complement. These verbs are exceptional verbs. With this in mind, we can analyse the case marking in this sentence (the tree leaves out unnecessary data):
* wanted is an V (a prepositional complementiser), a lexical head.
* wanted m-commands him:
** him is dominated by IP, which is a sister of wanted. Neither dominates the other.
** The first maximal projection of wanted is the VP, which dominates me.
* There are no barriers between the V and DP (IP is not a barrier)
Thus wanted assigns Case to him. This is Exceptional Case-Marking.
Note that this structure is actually not very common. In French, for example, wanted takes a CP complement:
(6) Je veux que tu finisses tes devoirs. (I want that you finish your homeworks)