Published online by Cambridge University Press: 22 April 2026
The following article is, first, an algorithm or set of rules for deriving the phonology of Proto-Germanic from that of Indo-European. The input to this set of rules consists of individual IE lexical items specified completely (i.e. allophonically) in terms of Jakobsonian distinctive features; the output consists of the corresponding lexical items of Proto-Germanic. Second, the article gives a criterion of simplicity for the construction of a similar algorithm describing phonological change from a prior stage of a language to a later one. The claim made for such a set of optimally written rules is that if one orders the rules so that the fewest possible feature specifications are used in their formulation, the order in which the rules occur reflects the historical chronology of the sound changes.