---
title: "Three Models for the Description of Language"
authors:
  - "Noam Chomsky"
year: 1956
venue: "IRE Transactions on Information Theory"
arxiv: null
doi: "10.1109/TIT.1956.1056813"
source: "https://doi.org/10.1109/TIT.1956.1056813"
topics:
  - formal-grammars
  - chomsky
  - language
  - automata
seed_rank: 599
seed_batch: "foundations-greats-2026-08-13"
reviewed: "2026-08-13"
pool: "languages"
relevance_score: 10
lineage: foundations-of-computing
cites:
  - title: "Syntactic Structures"
    url: "https://doi.org/10.1515/9783112316009"
    year: 1957
    arxiv: null
    doi: "10.1515/9783112316009"
  - title: "On Certain Formal Properties of Grammars"
    url: "https://doi.org/10.1016/S0019-9958(59)90362-6"
    year: 1959
    arxiv: null
    doi: "10.1016/S0019-9958(59)90362-6"
  - title: "Prediction and Entropy of Printed English"
    url: "https://doi.org/10.1002/j.1538-7305.1951.tb01366.x"
    year: 1951
    arxiv: null
    doi: "10.1002/j.1538-7305.1951.tb01366.x"
see:
  - "600-syntactic-structures"
  - "601-on-certain-formal-properties-of-grammars"
  - "558-prediction-and-entropy-of-printed-english"
---

# Three Models for the Description of Language

## One-sentence takeaway

Chomsky shows finite-state Markov sources cannot generate English, then compares phrase-structure and transformational models as stronger descriptions.

## Why it matters here

Parsers, grammars, and the Chomsky hierarchy in the languages pool start at this 1956 IRE-IT paper, not at the 1957 book.

## Key ideas

- Model 1: finite-state (n-gram / Markov) devices; English has unbounded nested dependencies they cannot capture.
- Model 2: phrase-structure (context-free style) grammars generate constituent trees but still miss systematic relations between sentences.
- Model 3: a transformational component maps kernel sentences to passives, questions, and other related forms.
- The paper is the technical seed of *Syntactic Structures* and of later formal-language theory.
- Same IRE Information Theory issue era as Logic Theorist.

## Caveats

## Links

- DOI: [10.1109/TIT.1956.1056813](https://doi.org/10.1109/TIT.1956.1056813)
- URL: https://doi.org/10.1109/TIT.1956.1056813