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Article published In: Historiographia Linguistica
Vol. 52:2 (2025) ► pp.269–303

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The prehistory of generative grammar and Chomsky’s debt to Emil Post

 | University of Edinburgh
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Available under the Creative Commons Attribution (CC BY) 4.0 license.

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Open Access publication of this article was funded through a Transformative Agreement with University of Edinburgh.

Published online: 23 October 2025
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https://doi.org/10.1075/hl.00186.pul
Summary
Generative linguistics has a longer prehistory than most linguists realize. The rewriting systems that Chomsky brought into linguistics as generative grammars were explicitly defined more than a century ago, as part of a project to formalize inference rules in logic, and were later applied to studying mathematical properties of certain kinds of infinite sets. Their developer was the mathematician and logician Emil Leon Post, whose work was inspired by Clarence Irving Lewis and Cassius Jackson Keyser. Post also proved the first two theorems about what linguists now call generative capacity. The idea of deploying Post’s systems within linguistics was first suggested in 1950 by the logician Paul Rosenbloom. I review the relevant pre-1950 work, and explore the reasons for its having remained so little known among linguists.
Résumé
La linguistique générative a une préhistoire plus longue que ne le pensent la plupart des linguistes. Les systèmes de réécriture que Chomsky a introduits en linguistique sous le nom de grammaires génératives avaient été explicitement définis il y a plus d’un siècle, dans le cadre d’un projet visant à formaliser les règles d’inférence en logique et ont été ensuite appliqués à l’étude des propriétés mathématiques de certains types d’ensembles infinis. La paternité de ces travaux revient au mathématicien et logicien Emil Leon Post, qui a lui-même été inspiré par les travaux de Clarence Irving Lewis et Cassius Jackson Keyser. Post a également prouvé les deux premiers théorèmes sur ce que les linguistes appellent aujourd’hui la capacité générative. L’idée d’utiliser les systèmes de Post en linguistique a été suggérée pour la première fois en 1950 par le logicien Paul Rosenbloom. Je passe en revue les travaux pertinents antérieurs à 1950 et explore les raisons pour lesquelles ils sont restés si peu connus des linguistes.
Zusammenfassung
Die generative Linguistik hat eine längere Vorgeschichte, als den meisten Linguisten bewusst ist. Die Umschreibungssysteme, die Chomsky als generative Grammatiken in die Linguistik einführte, wurden vor mehr als einem Jahrhundert im Rahmen eines Projekts zur Formalisierung von Inferenzregeln in der Logik explizit definiert und später auf die Untersuchung mathematischer Eigenschaften bestimmter Arten von unendlichen Mengen angewendet. Diese Systeme wurden vom Mathematiker und Logiker Emil Leon Post entwickelt, dessen Arbeiten ihrerseits von Clarence Irving Lewis und Cassius Jackson Keyser inspiriert wurden. Post lieferte auch den Beweis für die ersten beiden Theoreme über das, was Linguisten heute als generatives Vermögen bezeichnen. Der Gedanke, Posts Systeme in der Linguistik einzusetzen, wurde erstmals 1950 vom Logiker Paul Rosenbloom vorgeschlagen. Der vorliegende Beitrag gibt einen Überblick über die relevanten Arbeiten vor 1950 und untersucht die Gründe dafür, dass sie unter Linguisten so wenig bekannt sind.
Article outline
  • 1.Introduction
    • 1.1A few terminological preliminaries
      • Grammars
      • Languages
      • Generativity
      • Stringsets
      • Derivations
      • Algorithms
  • 2.Post’s rewriting systems and the mathematizing of logic
    • 2.1Separating syntax from semantics
    • 2.2From propositional to first-order logic
    • 2.3Publish or perish: The years of illness
  • 3.How Post’s production systems work
  • 4.Expressive power proofs
    • 4.1The Normal-Form Theorem
    • 4.2Axel Thue’s unsolvable word puzzle
  • 5.Priority, attribution, and citation
    • 5.1On the technical term ‘generate’
    • 5.2Chomsky’s acknowledgements of Post
    • 5.3Chomsky’s own account of his learning about Post
    • 5.4The Rosenbloom textbook
    • 5.5The puzzle of Chomsky’s blind spot, and its solution
  • 6.Concluding remarks
  • Acknowledgements
  • Notes
  • References
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