Binding (linguistics)

When one examines the distribution of reflexive pronouns and reciprocal pronouns (which are often subsumed under the general category of "anaphor"), one sees that there are certain domains that are relevant, a "domain" being a syntactic unit that is clause-like. Reflexive and reciprocal pronouns often seek their antecedent close by, in a binding domain that is local, e.g.

a. Fred_i praises himself_i. – Indicated reading obligatory

b. *Fred_i praises him_i. – Indicated reading impossible

a. The girls_i like each other_i. – Indicated reading obligatory

b. *The girls_i like them_i. – Indicated reading impossible

These examples illustrate that there is a domain within which a reflexive or reciprocal pronoun should find its antecedent. The a-sentences are fine because the reflexive or reciprocal pronoun has its antecedent within the clause. The b-sentences, in contrast, do not allow the indicated reading, a fact illustrating that personal pronouns have a distribution that is different from that of reflexive and reciprocal pronouns. A related observation is that a reflexive and reciprocal pronoun often cannot seek its antecedent in a superordinate clause, e.g.

a. Susan thinks that Jill_i should praise herself_i. – Indicated reading (almost) obligatory

b. ^??Susan_i thinks that Jill should praise herself_i. – Indicated reading very unlikely

a. They asked whether the girls_i like each other_i. – Indicated reading (almost) obligatory

b. ^??They_i asked whether the girls like each other_i. – Indicated reading very unlikely

When the reflexive or reciprocal pronoun attempts to find an antecedent outside of the immediate clause containing it, it fails. In other words, it can hardly seek its antecedent in the superordinate clause. The binding domain that is relevant is the immediate clause containing it.

Personal pronouns have a distribution that is different from reflexive and reciprocal pronouns, a point that is evident with the first two b-sentences in the previous section. The local binding domain that is decisive for the distribution of reflexive and reciprocal pronouns is also decisive for personal pronouns, but in a different way. Personal pronouns seek their antecedent outside of the local binding domain containing them, e.g.

a. Fred_i asked whether Jim mentioned him_i. – Indicated reading easily possible

b. *Fred asked whether Jim_i mentioned him_i. – Indicated reading impossible

a. Gina_i hopes that Wilma will mention her_i. – Indicated reading easily possible

b. *Gina hopes that Wilma_i will mention her_i. – Indicated reading impossible

In these cases, the pronoun has to look outside of the embedded clause containing it to the matrix clause to find its antecedent. Hence based on such data, the relevant binding domain appears to be the clause. Further data illustrate, however, that the clause is actually not the relevant domain:

a. Fred_i likes the picture of him_i. – Indicated reading possible

b. Gina_i has heard the rumor about her_i. – Indicated reading possible

Since the pronouns appear within the same minimal clause containing their antecedents in these cases, one cannot argue that the relevant binding domain is the clause. The most one can say based on such data is that the domain is "clause-like".

The distribution of common and proper nouns is unlike that of reflexive, reciprocal, and personal pronouns. The relevant observation in this regard is that a noun is often reluctantly coreferential with another nominal that is within its binding domain or in a superordinate binding domain, e.g.

a. Susan_i admires herself_i. – Indicated reading obligatory

b. #Susan_i admires Susan_i. – Indicated reading possible, but special context necessary

a. Fred_i thinks that he_i is the best. – Indicated reading easily possible

b. #Fred_i thinks that Fred_i is the best. – Indicated reading possible, but special context necessary

The readings indicated in the a-sentences are natural, whereas the b-sentences are very unusual. Indeed, sentences like these b-sentences were judged to be impossible in the traditional binding theory according to Condition C (see below). Given a contrastive context, however, the b-sentences can work, e.g. Susan does not admire Jane, but rather Susan_i admires Susan_i. One can therefore conclude that nouns are not sensitive to binding domains in the same way that reflexive, reciprocal, and personal pronouns are.

A simple hypothesis concerning the distribution of many anaphoric elements, of personal pronouns in particular, is that linear order plays a role. In most cases, a pronoun follows its antecedent, and in many cases, the coreferential reading is impossible if the pronoun precedes its antecedent. The following sentences suggest that pure linear can indeed be important for the distribution of pronouns:

a. Jim's_i grade upsets him_i. – Indicated reading easily possible

b. ^?His_i grade upsets Jim_i. – Indicated reading unlikely

a. Larry's_i family avoids him_i. – Indicated reading easily possible

b. ^?His_i family avoids Larry_i. – Indicated reading unlikely

a. We spoke to Tina's_i mother about her_i. – Indicated reading easily possible

b. ^?We spoke to her_i mother about Tina_i. – Indicated reading unlikely

While the coreferential readings indicated in these b-sentences are possible, they are unlikely. The order presented in the a-sentences is strongly preferred. The following, more extensive data sets further illustrate that linear order is important:

a. Sam_i mentioned twice that he_i was hungry. – Indicated reading easily possible

b. *He_i mentioned twice that Sam_i was hungry. – Indicated reading impossible

c. That Sam_i was hungry, he_i mentioned twice. – Indicated reading possible

d. ^?That he_i was hungry, Sam_i mentioned twice. – Indicated reading unlikely

a. You asked Fred_i twice when he_i would study. – Indicated reading easily possible

b. *You asked him_i twice when Fred_i would study. – Indicated reading impossible

c. When Fred_i would study, you asked him_i twice. – Indicated reading possible

d. ^?When he_i would study, you asked Fred_i twice. – Indicated reading unlikely

While the acceptability judgements here are nuanced, one can make a strong case that pure linear order is at least in part predictive of when the indicated reading is available. The a- and c-sentences allow the coreferential reading more easily than their b- and d-counterparts.

While linear order is an important factor influencing the distribution of pronouns, it is not the only factor. The following sentences are similar to the c- and d-sentences in the previous section insofar as an embedded clause is present.

a. When the boys_i are at home, they_i play video games. – Indicated reading easily possible

b. When they_i are at home, the boys_i play video games. – Indicated reading possible

a. If Susan_i tries, she_i will succeed. – Indicated reading easily possible

b. If she_i tries, Susan_i will succeed. – Indicated reading possible

While there may be a mild preference for the order in the a-sentences here, the indicated reading in the b-sentences is also available. Hence linear order is hardly playing a role in such cases. The relevant difference between these sentences and the c- and d-sentences in the previous section is that the embedded clauses here are adjunct clauses, whereas they are argument clauses above. The following examples involve adjunct phrases:[4]

a. Rosa_i found a scratch in Ben's picture of her_i. – Indicated reading easily possible

b. *She_i found a scratch in Ben's picture of Rosa_i. – Indicated reading impossible

c. ^?In Ben's picture of Rosa_i, she_i found a scratch. – Indicated reading unlikely

d. In Ben's picture of her_i, Rosa_i found a scratch. – Indicated reading possible

a. Zelda_i spent her sweetest hours in her_i bed.– Indicated reading easily possible

b. *She_i spent her sweetest hours in Zelda's_i bed. – Indicated reading impossible

c. ^??In Zelda's_i bed, she_i spent her sweetest hours. – Indicated reading very unlikely

d. In her_i bed, Zelda_i spent her sweetest hours. – Indicated reading possible

The fact that the c-sentences marginally allow the indicated reading whereas the b-sentences do not at all allow this reading further demonstrates that linear order is important. But in this regard, the d-sentences are telling, since if linear order were the entire story, one would expect the d-sentences to be less acceptable than they are. The conclusion that one can draw from such data is that there are one or more other factors beyond linear order that are impacting the distribution of pronouns.

C-command is a configurational notion that acknowledges the syntactic configuration as primitive. Basic subject-object asymmetries, which are numerous in many languages, are explained by the fact that the subject appears outside of the finite verb phrase (VP) constituent, whereas the object appears inside it. Subjects therefore c-command objects, but not vice versa. C-command is defined as follows:

C-command

Node A c-commands node B if every node dominating A also dominates B, and neither A nor B dominates the other.[6]

Given the binary division of the clause (S → NP + VP) associated with most phrase structure grammars, this definition sees a typical subject c-commanding everything inside the verb phrase (VP), whereas everything inside the VP is incapable of c-commanding anything outside of the VP. Some basic binding facts are explained in this manner, e.g.

a. Larry_i promoted himself_i. – Indicated reading obligatory

b. *Himself_i promoted Larry_i. – Indicated reading impossible; sentence ungrammatical

Sentence a is fine because the subject Larry c-commands the object himself, whereas sentence b does not work because the object Larry does not c-command the subject himself. The assumption has been that within its binding domain, a reflexive pronoun must be c-commanded by its antecedent. While this approach based on c-command makes a correct prediction much of the time, there are other cases where it fails to make the correct prediction, e.g.

The picture of himself_i upsets Larry_i. – Indicated reading possible

The reading indicated is acceptable in this case, but if c-command were the key notion helping to explain where the reflexive can and must appear, then the reading should be impossible since himself is not c-commanded by Larry.[7]

As reflexive and personal pronouns occur in complementary distribution, the notion of c-command can also be used to explain where personal pronouns can appear. The assumption is that personal pronouns cannot c-command their antecedent, e.g.

a. When Alice_i felt tired, she_i lay down. – Indicated reading easily possible

b When she_i felt tired, Alice_i lay down. – Indicated reading possible

In both examples, the personal pronoun she does not c-command its antecedent Alice, resulting in the grammaticality of both sentences despite reversed linear order.

The alternative to a c-command approach posits a ranking of syntactic functions (SUBJECT > FIRST OBJECT > SECOND OBJECT > PREPOSITIONAL OBJECT).[8] Subject-object asymmetries are addressed in terms of this ranking. Since subjects are ranked higher than objects, an object can have the subject as its antecedent, but not vice versa. With basic cases, this approach makes the same prediction as the c-command approach. The first two sentences from the previous section are repeated here:

a. Larry_i promoted himself_i. – Indicated reading obligatory

b. *Himself_i promoted Larry_i. – Indicated reading impossible; sentence ungrammatical

Since the subject outranks the object, sentence a is predictably acceptable, the subject Larry outranking the object himself. Sentence b, in contrast, is bad because the subject reflexive pronoun himself outranks its postcedent Larry. In other words, this approach in terms of rank is assuming that within its binding domain, a reflexive pronoun may not outrank its antecedent (or postcedent). Consider the third example sentence from the previous section in this regard:

The picture of himself_i upset Larry_i. – Indicated reading possible

The approach based on rank does not require a particular configurational relationship to hold between a reflexive pronoun and its antecedent. In other words, it makes no prediction in this case, and hence does not make an incorrect prediction. The reflexive pronoun himself is embedded within the subject noun phrase, which means that it is not the subject and hence does not outrank the object Larry.

A theory of binding that acknowledges both linear order and rank can at least begin to predict many of the marginal readings.[9] When both linear order and rank combine, acceptability judgments are robust, e.g.

a. Barbara_i hopes that she_i will be promoted. – Linear order and rank combine to make the indicated reading easily possible.

b. *She_i hopes that Barbara_i will be promoted. – Linear order and rank combine to make the indicated reading impossible.

a. Bill's_i grade upset him_i. – Linear order alone makes the indicated reading possible; rank is not involved.

b. ^?His_i grade upset Bill_i. – Linear order alone makes the indicated reading unlikely; rank is not involved.

This ability to address marginal readings is something that an approach combining linear order and rank can accomplish, whereas an approach that acknowledges only c-command cannot do the same.