In linguistics, pied-piping is a phenomenon of syntax whereby a given focused expression takes an entire encompassing phrase with it when it is "moved". The term itself is due to John Robert Ross; it is a reference to the Pied Piper of Hamelin, the figure of fairy tales who lured rats (and children) by playing his flute. Pied-piping is an aspect of discontinuities in syntax, having to do with the constituents that can and cannot be discontinuous. While pied-piping is most visible in cases of wh-fronting of information questions and relative clauses, it is not limited to wh-fronting, but rather it can be construed as occurring with most any type of discontinuity (extraposition, scrambling, topicalization). Most if not all languages that allow discontinuities employ pied-piping to some extent, although there are major differences across languages in this area, some languages employing pied-piping much more than others.
Typical examples of pied-piping occur when a wh-expression drags with it an entire encompassing phrase to the front of the clause. The focused expression is in bold in the following examples and the fronted word/phrase in the b- and c-sentences is underlined. The material that has been pied-piped is therefore any underlined material that is not bolded. The gap marks the canonical position of the fronted expression:
- a. She bought the red house.
- b. Which house did she buy ___? - The interrogative word which has pied-piped the noun house.
- c. *Which did she buy ___ house? - The sentence is bad because pied-piping has not occurred.
- a. She is ten years old.
- b. How old is she ___? - The interrogative word how has pied-piped the adjective old.
- c. *How is she ___ old? - The sentence is bad because pied-piping has not occurred.
- a. John left the scene very slowly.
- b. How slowly did John leave the scene ___? - The interrogative word how has pied-piped the adverb slowly.
- c. *How did John leave the scene ___ slowly? - The sentence is bad because pied-piping has not occurred.
In each of the b-sentences, the interrogative word has pied-piped an encompassing phrase with it, whereas each c-sentence is bad because pied-piping has not occurred. These examples illustrate that the pied-piped phrase can be a noun phrase, an adjective phrase, or an adverb phrase, and examples further below illustrate that it can also be a prepositional phrase. Pied-piping occurs in embedded wh-clauses as well:
- a. Sarah likes someone's paper.
- b. Sam asked whose paper Sarah likes ___. - The interrogative word whose has pied-piped the noun paper.
- c. *Sam asked whose Sarah likes ___ paper. - The sentence is bad because pied-piping has not occurred.
And pied-piping is very frequent in relative clauses, where a greater flexibility about what can or must be pied-piped is discernible:
- a. He likes stories about hobbits.
- b. ...hobbits stories about whom he likes ___ - The relative pronoun whom has pied-piped stories about.
- c. ...hobbits about whom he likes stories ___ - The relative pronoun whom has pied-piped the word about.
- d. ...hobbits who he likes stories about ___ - The relative pronoun who has pied-piped nothing; pied-piping has not occurred.
Wh-clauses vs. relative clauses
The pied-piping mechanism is more flexible in relative clauses in English than in interrogative clauses, because it can pied-pipe material that would be less acceptable in the corresponding interrogative clause, e.g.
- a. She laughed because of the face you made.
- b. ?Because of what did she laugh ___? - Pied-piping seems marginally acceptable in this matrix wh-clause.
- c. *We asked because of what she laughed ___? - Pied-piping is simply bad in this embedded wh-clause.
- d. ...the face you made because of which she laughed ___ - Pied-piping is possible in this relative clause.
- a. Tom likes your picture of Susan.
- b. ??Your picture of whom does Tom like ___? - Pied-piping seems strongly marginal in this matrix wh-clause.
- c. *They know your picture of whom Tom likes ___? - Pied-piping is simply bad in this embedded wh-clause.
- d. ...Susan, your picture of whom Tom likes ___ - Pied-piping is possible in this relative clause.
The d-examples, where pied-piping has occurred in a relative clause, are acceptable, whereas the corresponding wh-clauses in the b- and c-sentences are much less acceptable. This aspect of pied-piping - i.e. that it is more restricted in wh-clauses than in relative clauses in English - is poorly understood, especially in light of the fact that the same contrast in acceptability does not obtain in closely related languages such as German.
Pied-piping in English is optional with many prepositions (in, of, on, to, with, etc.). Colloquial registers prefer to avoid pied-piping whenever possible, whereas a more formal register can opt for pied-piping. The issue is understood in terms of preposition stranding. When a preposition is stranded, pied-piping has not occurred, whereas when preposition stranding is avoided, pied-piping of the preposition has occurred, e.g.
- a. Fred spoke with Susan.
- b. With whom did Fred speak ___. - Formal register allows pied-piping; preposition stranding is avoided.
- c. Who did Fred speak with ___? - Colloquial register dislikes pied-piping; preposition stranding occurs.
- a. Fred is waiting for Susan.
- b. For whom is Fred waiting ___? - Formal register allows pied-piping; preposition stranding is avoided.
- c. Who is Fred waiting for ___? - Colloquial register dislikes pied-piping; preposition stranding occurs.
The debate surrounding the stylistic acceptability of preposition stranding can hence be illuminated by an understanding of pied-piping.
Pied-piping broadly construed
Broadly construed, pied-piping occurs in other types of discontinuities beyond wh-fronting, that is, if one views just part of a topicalized or extraposed phrase as focused, then pied-piping can be construed as occurring with these other types of discontinuities, e.g.
- a. She called his parents, not her parents.
- b. His parents she called, not her parents. - Topicalization can be construed as involving pied-piping.
- a. The student who I know helped, not the student who you know.
- b. The student helped who I know, not the student who you know. - Extraposition can be construed as involving pied-piping.
Assuming that just the bolded words in these examples bear contrastive focus, the rest of the topicalized or extraposed phrase is pied-piped in each b-sentence. Similar examples could be produced for scrambling.
Pied-piping across languages
Pied-piping varies significantly across languages. Languages with relatively strict word order tend to employ pied-piping more often than languages that have freer word order. Hence English, with its relatively strict word order, employs pied piping more often than, for instance, the Slavic languages, with their relatively free word order. Three examples - one from Russian, one from Latin, and one from German - are now employed to illustrate the variation in pied-piping across languages. Unlike in English, a pre-noun modifier in Russian and Latin need not pied-pipe the noun that it modifies, e.g.
Č′jui ty čitaješ knigu? whose you read book 'Whose book are you reading?'
Cuius legis librum? whose you read book 'Whose book are you reading?'
When the word order here of Russian and Latin is maintained in English, the sentences are bad. They are bad because pre-noun modifiers necessarily pied-pipe their noun in English. The constraint is known as the Left Branch Condition: a modifier on a left branch under a noun may not be extracted from the noun phrase. Apparently, the Left Branch Condition is absent from Russian. The second example illustrating variation in pied-piping across languages is from German. Relative pronouns in German at times have the option to pied-pipe a governing zu-infinitive when they are fronted, e.g.
a. ...das Buch, das zu lesen ich versuchte the book that to read I tried 'the book that I tried to read'
b. ...das Buch, das ich zu lesen versuchte the book that I to read tried 'the book that I tried to read'
The a-sentence has the relative pronoun das pied-piping the zu-infinitive zu lesen to the front of the relative clause, whereas this pied-piping does not occur in the b-sentence. Since both variants are acceptable, pied-piping in such cases is optional. In English in contrast, pied-piping in such constellations is impossible, e.g. *the book that to read I tried and *the book to read which I tried.
The fact that pied-piping varies so much across languages is a major challenge facing theories of syntax.
- For a similar definition of pied-piping, see Crystal (1997;294).
- Ross introduced the concept of pied-piping in his seminal dissertation (1967/86:121ff.).
- Pied-piping is a concept discussed in many introductory texts to syntax, e.g. Riemsdijk (1986:28ff.), Haegeman (1994: 375f.), Roberts (1997:189).
- The greater flexibility of pied-piping in relative clauses is noted by, for instance, Culicover (1997:183).
- The differences between pied-piping in wh-clauses and relative clauses are discussed by Horvath (2006:579f).
- Pied-piping as it relates to preposition stranding is discussed in the literature frequently, e.g. Riemsdijk and Williams (1986:146f.), Haegeman (1994:375f.), Ouhalla (1994:70), and Radford (2004:106ff.).
- The two examples are taken from Roberts (1997:189).
- Like the concept of pied-piping itself, the Left Branch Condition was first identified by John Robert Ross in his seminal dissertation (1967/86:127).
- The Left Branch Condition is commonly introduced together with the concept of pied-piping, e.g. Riemsdijk and Williams (1986:28ff.) and Roberts(1987:189).
- The examples produced here are similar to those discussed by Osborne (2005:252f.).
- Crystal, D. 1997. A dictionary of linguistics and phonetics, 4th edition. Oxford, UK: Blackwell Publishers.
- Culicover, P. 1997. Principles and Parameters: An introduction to syntactic theory. New York: Oxford University Press.
- Haegeman, L. 1994. Introduction to Government and Binding Theory. Second edition. Oxford, UK: Blackwell.
- Horvath, J. 2006. Pied-piping. In The Blackwell companion to syntax, Volume III, edited by M. Everaert and H. van Riemsdijk, 569-630. Malden, MA: Blackwell Publishing.
- Osborne, T. 2005. Coherence: A dependency grammar analysis. SKY Journal of Linguistics 18, 223-286.
- Ouhalla, J. 1994. Introducing transformational grammar: From Principles and Parameters to Minimalism. Second edition. London: Arnold.
- Radford, A. 2004. English syntax: An introduction. Cambridge, UK: Cambridge University Press.
- Riemsdijk, Henk van and E. Williams. 1986. Introduction to the theory of grammar. Cambridge, MA: The MIT Press.
- Roberts, I. 1997. Comparative syntax. London: Arnold.
- Ross, J. 1967. Constraints on variables in syntax. Ph.D. Dissertation, MIT.
- Ross, J. 1986. Infinite syntax! Norwood, NJ: ABLEX [Reprinted dissertation from 1967].