"In general," says Tom McArthur, "Grimm's Law holds that unvoiced IE [Indo-European] stops became Germanic unvoiced continuants, that voiced IE stops became Germanic unvoiced stops, and that unvoiced IE continuants became Germanic voiced stops" (Concise Oxford Companion to the English Language, 2005).
The basic principle of Grimm's law was discovered early in the 19th century by Danish scholar Rasmus Rask, and soon afterward it was described in detail by German philologist Jacob Grimm.
- Historical Linguistics
- Key Dates in the History of the English Language
- Language Change
- Language Family
- Sound Change
Examples and Observations:
- "Rask's and Grimm's work . . . succeeded in establishing once and for all that the Germanic languages are indeed part of Indo-European. Secondly, it did so by providing a brilliant account for the differences between Germanic and the classical languages in terms of a set of amazingly systematic sound changes."
(H. H. Hock and B. D. Joseph, Language History, Language Change, and Language Relationship. Walter de Gruyter, 1996)
- A Chain Reaction
"Grimm's Law can be considered a chain reaction: aspirated voice stops become regular voiced stops, voiced stops in turn become voiceless stops, and voiceless stops become fricatives. . . .
"Examples of this change taking place at the beginning of words are provided in (1) . . .. Sanskrit is the first form given (except for kanah which is Old Persian), Latin the second, and English the third. It is important to remember that the change takes place only once in a word: dhwer corresponds to door but the latter does not change to toor:
- ghordho-hortus-yard (<Old English geard)
- kanab-cannabis-hemp (<Old English henep)
(Elly van Gelderen, A History of the English Language. John Benjamins, 2006)
- A Sequence of Changes
"It remains unclear whether Grimm's Law was in any sense a unitary natural sound change or a series of changes that need not have occurred together. It is true that no sound change can be shown to have occurred between any of the components of Grimm's Law; but since Grimm's Law was among the earliest Germanic sound changes, and since the other early changes that involved single non-laryngeal obstruents affected only the place of articulation and rounding of dorsals . . ., that could be an accident. In any case, Grimm's Law is most naturally presented as a sequence of changes that counterfed each other."
(Donald Ringe, A Linguistic History of English: From Proto-Indo-European to Proto-Germanic. Oxford Univ. Press, 2006)