Kluge's law is a controversial Proto-Germanic sound law formulated by Friedrich Kluge. It purports to explain the origin of the Proto-Germanic long consonants , , and (Proto-Indo-European lacked a phonemic length distinction for consonants) as originating in the assimilation of to a preceding voiced plosive consonant, under the condition that the was part of a suffix which was stressed in the ancestral Proto-Indo-European (PIE). The name "Kluge's law" was coined by Friedrich Kauffmann and revived by Frederik Kortlandt. As of 2006, the law was not generally accepted by historical linguists.
The resulting long consonants would subsequently have been shortened, except when they followed a short vowel; this is uncontroversial for (which has a different origin). Proponents of Kluge's law use this to explain why so many Proto-Germanic roots (especially of strong verbs) end in short , , or even though their likely cognates in other Indo-European languages point to final Proto-Indo-European consonants other than the expected , , , or . (Indeed, non-Germanic evidence for Proto-Indo-European is so rare that may not have been a phoneme at all; yet, in Proto-Germanic, was rare only at the beginnings of words.)
Much like Verner's law, Kluge's law would have created many consonant alternations in the grammatical paradigm of a word that were becoming only partially predictable. Analogical simplifications of these complexities are proposedKroonen, Guus Jan (2009). Consonant and vowel gradation in the Proto-Germanic n-stems. Doctoral thesis, Universiteit Leiden. Updated and extended version of Kroonen (2009). as an explanation for the many cases where closely related (often otherwise identical) words point to short, long, plosive, fricative, voiceless or voiced Proto-Germanic consonants in closely related Germanic languages or dialects, even sometimes the same dialect.
Assimilation (Kluge's law proper) The origin of Proto-Germanic (PGmc) , , , and had already been explained in Kluge's time as resulting from the assimilation of consonant clusters across earlier morpheme boundaries: from earlier (Pre-Germanic) , from earlier , from earlier and , from earlier and . This is uncontroversial today,Moulton, William G. (1972). "The Proto-Germanic non-syllabics (consonants)". Pages 141–173 in van Coetsem, Frans (ed.): Toward a Grammar of Proto-Germanic. De Gruyter. except that may not have given in every case. A few examples with are:
PGmc < PIE > Sanskrit (all meaning "full") PGmc < PIE > Sanskrit (all meaning "wool") PGmc ("far") < PIE > Lithuanian ("last year") German , Old High German < PIE (e-grade); Russian < PIE (zero-grade) (all meaning "wave")
Kluge proposed to explain , , and the same way (examples cited after Kroonen):
PGmc < PIE > Latin (all meaning "to lick") Middle Dutch , Middle High German and later (both "to pluck, tear off") < PIE > Latin ("I break") PGmc (genitive singular) < PIE > Sanskrit , Latin (all meaning "bottom") PGmc < PIE > Latin (all meaning "to bump into something") PGmc < PIE > Ancient Greek , Latin (all meaning "to lick") PGmc "to pat" < PIE > Latin "I touch"
Without Kluge's law, *, *, *, *, *, and * would be expected, respectively, in the Germanic forms (according to Grimm's law and Verner's law).
Predictable exceptions Kluge's law did not operate behind stressed vowels, only in the same environment as Verner's law. Examples cited are after Kroonen:
PGmc ("oven") < PIE PGmc ("sacrifice", "meal") < PIE > Latin ("detriment"), Ancient Greek ("expenditure") PGmc < PIE > Sanskrit , Latin (all "sleep", "dream") PGmc < PIE > Latin (all "year") PGmc < PIE ("water"; in the nominative, in the genitive) > Latin ("wave", "[mass of] water") PGmc ("borrowed goods") < PIE > Sanskrit ("inheritance", "wealth") PGmc < PIE ("wagon")
Also, even when that condition was fulfilled, Kluge's law did not act on the descendants of Proto-Indo-European (Proto-Germanic following Verner's law). Examples cited after Kroonen:
PGmc ("house") < PIE PGmc ("double thread") < PIE PGmc ("to learn") < PIE ("to make oneself know", a mediopassive causative) PGmc ("work") < PIE PGmc genitive singular , genitive plural , accusative plural < PIE , , ("ox's, oxen's, oxen")
Shortening of long consonants in overlong syllables The rise of long consonant phonemes left the Pre-Germanic language with three kinds of syllables: short: with a short vowel, followed by a short consonant in the next syllable long: with a long vowel, a diphthong or a short vowel + ///, followed by a short consonant in the next syllableor a short vowel followed by a long consonant that spanned the syllable boundary overlong: with a long vowel, a diphthong or a short vowel + /// followed by a long consonant that spanned the syllable boundary
In other words, syllables could be long because of the specific vowel (or a following ///), or because a long consonant from the next syllable bled in. If both occurred, the syllable was overlong. See Mora (linguistics), which suggests that such overlong syllables are cross-linguistically rare.
All overlong syllables were then turned into long syllables by shortening the long consonant. This is uncontroversial for , which derives from Proto-Indo-European , and clusters across morpheme boundaries (which were probably pronounced in Proto-Indo-European):
Without shortening (short vowel followed by long consonant): PGmc "certain" < PIE "known" With shortening (long vowel followed by originally long consonant): PGmc "wise" < PIE > Latin "seen" With shortening (diphthong followed by originally long consonant): PGmc "command" < PIE "act of calling"
Kluge proposed to extend this explanation to cases where Proto-Germanic roots that constituted long syllables ended in , , or , while different consonants at the same places of articulation would be expected based on apparently related roots (in Proto-Germanic or other Indo-European branches). Examples cited after Kroonen:
PGmc ("deep") as if from PIE ; Lithuanian ("deep", "hollow") from PIE PGmc ("sheep"), but ("to scrape/shear/shave") PGmc as if from PIE ; Sanskrit , from PIE (all meaning "white") PGmc ("glove/mitten"), but ("to wind") PGmc ("dam/dike", "pool") as if from PIE or ; Ancient Greek ("wall") from PIE or PGmc as if from PIE or ; Ancient Greek from PIE or (all meaning "to show")
Consequences for Proto-Germanic morphology Kluge's law had a noticeable effect on Proto-Germanic morphology. Because of its dependence on ablaut and accent, it operated in some parts of declension and conjugation, but not in others, giving rise to alternations of short and long consonants in both nominal and verbal paradigms. Kroonen compared these alternations to grammatischer Wechsel (the alternation of voiced and voiceless fricatives in Proto-Germanic, caused by Verner's law) and especially to the consonant gradation of the neighboring Finnic and Sami languages. This is most conspicuous in the n-stem nouns and the "néh₂-presents" (imperfective verbs formed from perfective ones by adding the Proto-Indo-European suffix /), but also occurs in mn-stems and directional adverbs.
n-stem nouns Kluge's law created long consonants in the genitive singular, which ended in in Proto-Indo-European, and in the genitive plural (). It did not operate in the dative plural: although the of was in direct contact with the root in Proto-Indo-European, it was syllabic, so it became early on the way to Proto-Germanic (soon assimilated to ), preventing the operation of Kluge's law.
Schematic (after Kroonen), where C represents the initial and the final consonant of the root, and G represents its Verner variant if it had one:
n-stem paradigm PIE PGmc nominative sg. C_́C-ō C_C-ô genitive sg. C_C-n-és C_CC-iz locative > dative sg. C_C-én-i C_G-ini accusative sg. C_C-ón-m̥ C_G-anų nominative pl. C_C-ón-es C_G-aniz genitive pl. C_C-n-óHom C_CC-ǫ̂ dative pl. C_́C-n̥-mis C_C-ummiz accusative pl. C_C-on-n̥s C_G-unz
Example:
"fever" PIE PGmc nominative sg. genitive sg. locative > dative sg. accusative sg.
Naturally, this led to three different kinds of consonant alternation (examples after Kroonen):
friction + voice + length friction + length length only nominative sg. genitive sg. Meaning twig/branch, prong stringing pole, line wick infertile animal
The nominative singular of roots ending in plosives thus became difficult to predict from the cases where Kluge's law had operated; and the pure length opposition was more common than the others, because it was not limited to plosives.
mn-stem nouns In Proto-Indo-European, such words regularly would have had a nominative singular in and a genitive in . However, in the genitive singular, it appears that the dropped out of the middle of the resulting three-consonant cluster already in PIE, making the mn-stems look like n-stems: Proto-Indo-European , > , ("bottom") > Ancient Greek from the nominative, but Sanskrit and Latin from the genitive. This would have allowed assimilation of to the now preceding consonant; Kroonen (2011) proposed that this happened in such words, yielding e.g. Proto-Germanic , ("bottom").
Directional adverbs In addition to prepositions that indicated relative locations (such as "in" or "over"), Proto-Germanic had a large set of directional adverbs: "locative" ones (with meanings such as "inside" or "on top"), "allative" ones (with meanings such as "into" or "up") and "ablative" ones (with meanings such as "out from the inside" or "down from above"). Many, but not all of these forms had long consonants. Kroonen (2011, 2012)Kroonen, Guus (2012). "Consonant gradation in the Germanic iterative verbs". Pages 263–290 in Nielsen Whitehead, Benedicte, Olander, Thomas, Olsen, Birgit Anette & Elmegård Rasmussen, Jens (eds.): The Sound of Indo-European – Phonetics, Phonemics, and Morphophonemics. Museum Tusculanum. [Presented to the conference "The Sound of Indo-European – Phonetics, Phonemics, and Morphophonemics" in Copenhagen in 2009.] reconstructed examples like this and attributed them to Kluge's law:
preposition "locative" "allative" "ablative" PIE or PGmc or meaning over on top up down from above
néh₂-"present" verbs: iteratives
néh₂-presents PIE PGmc 3p. singular C_C-néh₂-ti C_CC-ōþi 3p. plural C_C-n̥h₂-énti C_G-unanþi
Chronology
The law had sparked discussions about its chronology in relation to Grimm's law and Verner's law. The problem is that the traditional ordering (1. Grimm, 2. Verner, 3. Kluge) cannot account for the absence of voice in the Proto-Germanic geminates. Therefore, it has been proposed to rearrange the order of events so that the Proto-Germanic geminates' loss of voice may be equated with that part of Grimm's law that turns mediae into voiceless tenues. This would mean that characteristics noted in Kluge's law happened before (or between different phases of) those of Grimm's law. If accepted, this has further consequences, because those characteristics of Verner's law must in fact, precede those of Kluge's law, or otherwise it can not be explained why both the reflexes of Proto-Indo-European voiced aspirated plosives and Proto-Indo-European voiceless plosives underwent the changes characteristic in Kluge's law. Consequently, this would put Verner's law chronologically in the first position, followed by Kluge's, and finally by Grimm's law.
Under the updated view, the processes may be summarized by the following table: Pre-Proto-Germanic All three sets of stops occur before accented suffixes. Verner's law Voiceless stops occurring after an unaccented syllable are voiced. Kluge's law Stop + *n becomes, before an accented vowel, a geminate. Grimm's law and stress shift Voiced stops are devoiced, and accent is shifted to the initial syllable.
Criticism