# Evidence against the context-freeness of natural language

@article{Shieber1985EvidenceAT, title={Evidence against the context-freeness of natural language}, author={Stuart M. Shieber}, journal={Linguistics and Philosophy}, year={1985}, volume={8}, pages={333-343} }

In searching for universal constraints on the class of natural languages, linguists have investigated a number of formal properties, including that of context-freeness. Soon after Chomsky’s categorization of languages into his well-known hierarchy (Chomsky, 1963), the common conception of the context-free class of languages as a tool for describing natural languages was that it was too restrictive a class — interpreted strongly (as a way of characterizing structure sets) and even weakly (as a… Expand

#### 697 Citations

Learning of Context-Free Languages: A Survey of the Literature

- Computer Science
- 1996

This work surveys methods for learning context-free languages (CFL's) in the theoretical computer science literature, considering those that take text as input, those thatTake structural information as input), those that rely on CFL formalisms that are not based on context- free grammars, those which learn subclasses of CFL's, and stochastic methods. Expand

Computationally Relevant Properties of Natural Languages and Their Grammars

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- 1985

What is currently known about natural language morphology and syntax from the perspective of formal language theory is surveyed and recent developments such as feature-theory, the use of extension and unification, default mechanisms, and metagram-matical techniques are outlined. Expand

Computationally relevant properties of natural languages and their grammars

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What is currently known about natural language morphology and syntax from the perspective of formal language theory is surveyed and recent developments such as feature-theory, the use of extension and unification, default mechanisms, and metagrammatical techniques are outlined. Expand

Contextual Grammars versus Natural Languages

- Mathematics
- 1996

We continue here the investigations concerning the relevance of certain classes of contextual grammars (internal contextual grammars with maximal use of selectors) as generative models of natural… Expand

Formal language theory: refining the Chomsky hierarchy

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- Philosophical Transactions of the Royal Society B: Biological Sciences
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The arguments why neither regular nor context-free grammar is sufficiently expressive to capture all phenomena in the natural language syntax are recapitulated. Expand

Mildly Context-Sensitive Grammars

- Computer Science
- 2004

One of the most investigated families of languages is the family of context-free languages, which turn out to be very useful in many applications of formal languages and they have good mathematical properties. Expand

Global index languages

- Computer Science
- 2004

Describing power is shown both in terms of the set of string languages included in GILs, as well as the structural descriptions generated by the corresponding grammars, which preserves the desirable properties of context-free languages. Expand

The equivalence of four extensions of context-free grammars

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- 2005

The result presented in this paper is that all four of the formalisms under consideration generate exactly the same class of string languages. Expand

Grammar Formalisms for Natural Languages

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- 2010

For a long time there has been a debate about whether CFGs are sufficiently powerful to describe natural languages, but these approaches were able to treat a large range of linguistic phenomena. Expand

A formal universal of natural language grammar

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This article proposes that the possible word orders for any natural language construction composed of n elements, each of which selects for the category headed by the next, are universally limited… Expand

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