Problems concerning the transformation of
symbol sequences according to given rules

Probleme über Veränderungen von
Zeichenreihen nach gegebenen Regeln

Axel Thue, 1914

Axel Thue's paper of 1914 on string rewriting was made famous by Emil Post when, in 1947, he proved the word problem for Thue systems to be undecidable. Yet, only the first two pages of Thue's paper are directly relevant to Post's work in 1947, and the remaining 30 pages seem to have been cast into the shade.
Thue's paper has been "passed by reference" into the history of computing, based mainly on a small section of that work. A closer study of the remaining parts of that paper highlight a number of important themes in the history of computing: the transition from algebra to formal language theory, the analysis of the "computational power" (in a pre-1936 sense) of rules, and the development of algorithms to generate rule-sets.

James Power,
Dept. of Computer Science, Maynooth University
Last revised: Monday October 06, 2014