Sentence containing a pronoun with clear meaning but unclear syntactic role
In
semantics, donkey sentences are sentences that contain a
pronoun with clear meaning (it is semantically
bound) but whose
syntactic role in the sentence poses challenges to
linguists.[a] Such sentences defy straightforward attempts to generate their
formal language equivalents. The difficulty is with understanding how English speakers
parse such sentences.[b]
Barker and Shan define a donkey pronoun as "a pronoun that lies outside the restrictor of a
quantifier or the if-clause of a
conditional, yet
covaries with some
quantificational element inside it, usually an
indefinite."[3] The pronoun in question is sometimes termed a donkey pronoun or donkey
anaphora.
The following sentences are examples of donkey sentences.
"Omne homo habens asinum videt illum." ("Every man who owns a donkey sees it") —
Walter Burley (1328), De puritate artis logicae tractatus longior[4][5]
"Every police officer who arrested a murderer insulted him."
History
Walter Burley, a medieval scholastic philosopher, introduced donkey sentences in the context of the theory of suppositio, the medieval equivalent of reference theory.
The goal of
Montague grammar is to show how sentences of a natural language (like English) could be translated into a formal logical language, and so would then be amenable to mathematical analysis. Following
Russell, it is typical to translate
indefinite noun phrases using an
existential quantifier,[9]
as in the following simple example from Burchardt et al:
The prototypical donkey sentence, "Every farmer who owns a donkey beats it.", requires careful consideration for adequate description (though reading "each" in place of "every" does simplify the formal analysis). The donkey pronoun in this case is the word it. Correctly translating this sentence will require using a
universal quantifier for the indefinite noun phrase "a donkey", rather than the expected existential quantifier.
The naive first attempt at translation given below is not a well-formed sentence, since the variable is left
free in the predicate .[11]
It may be attempted to extend the
scope of the existential quantifier to bind the free instance of , but it still does not give a correct translation.[11]
This translation is incorrect since it is already true if there exists any object that is not a donkey: Given any object to be substituted for , substituting any non-donkey object for makes the
material conditional true (since its
antecedent is false), and so existential clause is true for every choice of .
A correct translation into first-order logic for the donkey sentence seems to be
,
indicating that indefinites must sometimes be interpreted as existential quantifiers, and other times as universal quantifiers.[11]
There is nothing wrong with donkey sentences: they are grammatically correct, they are well-formed and meaningful, and their syntax is regular. However, it is difficult to explain how donkey sentences produce their semantic results, and how those results generalize consistently with all other language use. If such an analysis were successful, it might allow a computer program to accurately translate natural language forms into
logical form.[12] It is unknown how natural language users are – apparently effortlessly – agreeing on the meaning of sentences such as the examples.[citation needed]
There may be several equivalent ways of describing this process. In fact,
Hans Kamp (1981) and
Irene Heim (1982) independently proposed very similar accounts in different terminology, which they called
discourse representation theory (DRT) and
file change semantics (FCS), respectively.
Theories of donkey anaphora
It is usual to distinguish two main kinds of theories about the semantics of donkey pronouns. The most classical proposals fall within the so-called description-theoretic approach, a label that is meant to encompass all the theories that treat the semantics of these pronouns as akin to, or derivative from, the semantics of
definite descriptions. The second main family of proposals goes by the name dynamic theories, and they model donkey anaphora – and anaphora in general – on the assumption that the meaning of a sentence lies in its potential to change the context (understood as the information shared by the participants in a conversation).[13]
Description-theoretic approaches
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adding to it. (March 2020)
Description-theoretic approaches are theories of donkey pronouns in which definite descriptions play an important role. They were pioneered by
Gareth Evans's E-type approach,[8] which holds that donkey pronouns can be understood as referring terms whose reference is fixed by description.
For example, in "Every farmer who owns a donkey beats it.", the donkey pronoun "it" can be expanded as a definite description to yield "Every farmer who owns a donkey beats the donkey he/she owns." This expanded sentence can be interpreted along the lines of Russell's
theory of descriptions.[14]
Later authors have attributed an even larger role to definite descriptions, to the point of arguing that donkey pronouns have the semantics,[15][16] and even the syntax,[17] of definite descriptions. Approaches of the latter kind are usually called D-type.
Donkey sentences became a major force in advancing
semantic research in the 1980s, with the introduction of
discourse representation theory (DRT). During that time, an effort was made to settle the inconsistencies which arose from the attempts to translate donkey sentences into
first-order logic.
The solution that
DRT provides for the donkey sentence problem can be roughly outlined as follows: The common semantic function of non-anaphoric
noun phrases is the introduction of a new
discourse referent, which is in turn available for the binding of anaphoric expressions. No quantifiers are introduced into the representation, thus overcoming the scope problem that the logical translations had.
Dynamic Predicate Logic
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adding to it. (March 2020)
^
abPeter Geach (1962). Reference and Generality. Ithaca and London: Cornell University Press – via philosophieweb0.001.free.fr/GeachRandG.pdf.
^Lewis, David (1975). "Adverbs of quantification". In Keenan, Edward L. (ed.). Formal Semantics of Natural Language. Cambridge: Cambridge University Press.
ISBN9780511897696 – via users.ox.ac.uk/~sfop0776/LewisQA.pdf.
^Cooper, Robin (1979). "The interpretation of pronouns". In Frank Heny; Helmut Schnelle (eds.). Syntax and Semantics 10: Selections from the third Gröningen roundtable. Academic Press.
ISBN012613510X.
Conway, L. and S. Crain. 'Donkey Anaphora in Child Grammar'. In Proceedings of the North East Linguistics Society (NELS) 25.
University of Massachusetts Amherst, 1995.
Kanazawa, Makoto. 'Weak vs. Strong Readings of Donkey Sentences and Monotonicity Inference in a Dynamic Setting'. Linguistics and Philosophy17 (1994): 109–158.
Krifka, Manfred. 'Pragmatic Strengthening in Plural Predications and Donkey Sentences'. In Proceedings from Semantics and Linguistic Theory (SALT) 6. Ithaca, New York:
Cornell University, 1996. Pages 136–153.
Lappin, Shalom. 'An Intensional Parametric Semantics for Vague Quantifiers'. Linguistics and Philosophy23 (2000): 599–620.
^David Lewis describes this as his motivation for considering the issue in the introduction to Papers in Philosophical Logic, a collection of reprints of his articles. "There was no satisfactory way to assign relative scopes to quantifier phrases."[2]
^In 2007, Adrian Brasoveanu published studies of donkey pronoun analogs in
Hindi, and analysis of complex and
modal versions of donkey pronouns in English.
Huang, C-T James.
'Logical Form'. Chapter 3 in Government and Binding Theory and the Minimalist Program: Principles and Parameters in Syntactic Theory edited by Gert Webelhuth. Oxford and Cambridge:
Blackwell Publishing, 1995. Pages 127–177.
Kitagawa, Yoshihisa.
'Copying Variables'. Chapter 2 in Functional Structure(s), Form and Interpretation: Perspectives from East Asian Languages. Edited by Yen-hui Audrey Li and others.
Routledge, 2003. Pages 28–64.