Principle A is a statement in the government and binding theory of syntax that is intended to answer questions such as these: Why in sentences such
as the following must 'Mary' and 'herself' refer to the same individual in the
first case? Why isn't the second sentence grammatical? Why can't 'Mary' and
'herself' refer to the same individual in the second case?
Maryi saw herselfi in the mirror
*Herselfi saw Maryi in the mirror
Possible (wrong) easy explanations
Linear order: 'Mary' and 'herself' have to occur in left-to-right order.
When they do, 'herself' takes 'Mary' as its antecedent.
The following show that this cannot be right. Even though 'Mary' and 'herself'
are in the supposedly correct order, and 'father' is not a possible antecedent
for 'herself', still the sentence is bad. Note also that on the most likely
interpretation it seems to imply that Mary's father is female. This suggests
that despite the implausibility of this interpretation, somehow 'herself' is
taking 'Mary's father' as its antecedent. In the second sentence the two key
terms appear in the supposedly correct order, but still something is amiss.
What?
*Maryi's father likes herselfi
*The book about Maryi fell on herselfi
Subjecthood: Perhaps, we might think, it is critical that 'Mary' be the
subject of the sentence. But even when 'Mary' is not the subject, there are
grammatical sentences where 'Mary' and 'herself' successfully corefer.
John likes Maryi's picture of herselfi
What sort of relationship?
How can we correctly describe the necessary relationship between anaphors (like
'herself') and their antecedents? To state the relationship we need to define
several terms, the most critical of which is c-command.
Definitions:
c-command: Node X c-commands Node Y iff (if and only if) the first node
dominating X also dominates Y.
co-indexing: Nodes are co-indexed if each carries the same subscript.
bound: An NP is bound iff it is co-indexed with a c-commanding NP.
free: Not bound.
Principle A applies to:
Maryi saw herselfi in the mirror
S
/ \
NP VP
| / \
N V NP
Mary saw / \
N PP
herself / \
P NP
in the mirror
John likes Maryi's picture of herselfi
S
/ \
NP VP
/ / \
N V NP
John likes / | \____
NP N PP
| picture / \
N P NP
Mary's of |
N
herself
*Maryi's father likes herselfi
These are difficult to draw, so I switch to a different but logically
equivalent form now...
(S
(NP
(NP
(N Mary's))
(N father))
(VP
(V likes)
(NP
(N herself))))
*Herselfi saw Maryi in the mirror
(S
(NP
(N herself))
(VP
(V saw)
(NP
(N Mary))
(PP
(P in)
(NP
(Art the)
(N mirror)))))
*The book about Maryi fell on herselfi
(S
(NP
(Art the)
(N book)
(PP
(P about)
(NP
(N Mary))))
(VP
(V fell)
(PP
(P on)
(NP
(N herself)))))
"An anaphor must be bound"
If this is correct, then it should predict which of the above sentences is
grammatical and ungrammatical -- under the specified interpretations. We have a
problem, however:
*Maryi thinks the boy saw herselfi
(S
(NP
(N Mary))
(VP
(V thinks)
(S
(NP
(Art the)
(N boy))
(VP
(V saw)
(NP
(N herself))))))
This indicates that we must modify the principle as follows:
An anaphor must be bound in its own clause.
Note: Anaphors MUST have an antecedent in the sentence. If "herself"
in the following sentence is taken to mean someone not mentioned in the
sentence, the sentence is ungrammatical.
*Maryi saw herselfj in the mirror
(S
(NP
(N Maryi))
(VP
(V saw)
(NP
(N herselfj)
(PP
(P in)
(NP
(Art the)
(N mirror))))))
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