Monthly Archives: September 2016

That’s OK, but this’s not OK?

Here’s something peculiar I noticed the other day about the English language.

The word is (the third-person singular present indicative form of the verb be) can be ‘contracted’ with a preceding noun phrase, so that it is reduced to an enclitic form -‘s. This can happen after pretty much any noun phrase, no matter how syntactically complex:

(1) he’s here

/(h)iːz ˈhiːə/[1]

(2) everyone’s here

/ˈevriːwɒnz ˈhiːə/

(3) ten years ago’s a long time

/ˈtɛn ˈjiːəz əˈgəwz ə ˈlɒng ˈtajm/

However, one place where this contraction can’t happen is immediately after the proximal demonstrative this. This is strange, because it can certainly happen after the distal demonstrative that, and one wouldn’t expect these two very similar words to behave so differently:

(4) that’s funny
/ˈðats ˈfʊniː/

(5) *this’s funny

There is a complication here which I’ve kind of skirted over, though. Sure, this’s funny is unacceptable in writing. But what would it sound like, if it was said in speech? Well, the -’s enclitic form of is can actually be realized on the surface in a couple of different ways, depending on the phonological environment. You might already have noticed that it’s /-s/ in example (4), but /-z/ in examples (1)-(3). This allomorphy (variation in phonological form) is reminiscent of the allomorphy in the plural suffix: cats is /ˈkats/, dogs is /ˈdɒgz/, horses is /ˈhɔːsɪz/. In fact the distribution of the /-s/ and /-z/ realizations of -‘s is exactly the same as for the plural suffix: /-s/ appears after voiceless non-sibilant consonants and /-z/ appears after vowels and voiced non-sibilant consonants. The remaining environment, the environment after sibilants, is the environment in which the plural suffix appears as /-ɪz/. And this environment turns out to be exactly the same environment in which -’s is unacceptable in writing. Here are a couple more examples:

(6) *a good guess’s worth something (compare: the correct answer’s worth something)

(7) *The Clash’s my favourite band (compare: Pearl Jam’s my favourite band)

Now, if -‘s obeys the same rules as the plural suffix then we’d expect it to be realized as /-ɪz/ in this environment. However… this is exactly the same sequence of segments that the independent word is is realized as when it is unstressed. One might therefore suspect that in sentences like (8) below, the morpheme graphically represented as the independent word is is actually the enclitic -‘s, it just happens to be realized the same as the independent word is and therefore not distinguished from it in writing. (Or, perhaps it would be more elegant to say that the contrast between enclitic and independent word is neutralized in this environment.)

(8) The Clash is my favourite band

Well, this is (*this’s) a very neat explanation, and if you do a Google search for “this’s” that’s pretty much the explanation you’ll find given to the various other confused people who have gone to websites like English Stack Exchange to ask why this’s isn’t a word. Unfortunately, I think it can’t be right.

The problem is, there are some accents of English, including mine, which have /-əz/ rather than /-ɪz/ in the allomorph of the plural suffix that occurs after sibilants, while at the same time pronouncing unstressed is as /ɪz/ rather than /əz/. (There are minimal pairs, such as peace is upon us /ˈpiːsɪz əˈpɒn ʊz/ and pieces upon us /ˈpiːsəz əˈpɒn ʊz/.) If the enclitic form of is does occur in (8) then we’d expect it to be realized as /əz/ in these accents, just like the plural suffix would be in the same environment. This is not what happens, at least in my own accent: (8) can only have /ɪz/. Indeed, it can be distinguished from the minimally contrastive NP (9):

(9) The Clash as my favourite band

In fact this problem exists in more standard accents of English as well, because is is not the only word ending in /-z/ which can end a contraction. The third-person singular present indicative of the verb have, has, can also be contracted to -‘s, and it exhibits the expected allomorphy between voiceless and voiced realizations:

(10) it’s been a while /ɪts ˈbiːn ə ˈwajəl/

(11) somebody I used to know’s disappeared /ˈsʊmbɒdiː aj ˈjuːst tə ˈnəwz dɪsəˈpijəd/

But like is it does not contract, at least in writing, after sibilants, although it may drop the initial /h-/ whenever it’s unstressed:

(12) this has gone on long enough /ˈðɪs (h)əz gɒn ɒn lɒng əˈnʊf/

I am not a native speaker of RP, so, correct me if I’m wrong. But I would be very surprised if any native speaker of RP would ever pronounce has as /ɪz/ in sentences like (12).

What’s going on? I actually do think the answer given above—that this’s isn’t written because it sounds exactly the same as this is—is more or less correct, but it needs elaboration. Such an answer can only be accepted if we in turn accept that the plural -s, the reduced -‘s form of is and the reduced -‘s form of has do not all exhibit the same allomorph in the environment after sibilants. The reduced form of is has the allomorph /-ɪz/ in all accents, except in those such as Australian English in which unstressed /ɪ/ merges with schwa. The reduced form of has has the allomorph /-əz/ in all accents. The plural suffix has the allomorph /-ɪz/ in some accents, but /-əz/ in others, including some in which /ɪ/ is not merged completely with schwa and in particular is not merged with schwa in the unstressed pronunciation of is.

Introductory textbooks on phonology written in the English language are very fond of talking about the allomorphy of the English plural suffix. In pretty much every treatment I’ve seen, it’s assumed that /-z/ is the underlying form, and /-s/ and /-əz/ are derived by phonological rules of voicing assimilation and epenthesis respectively, with the voicing assimilation crucially coming after the epenthesis (otherwise we’d have an additional allomorph /-əs/ after voiceless sibilants, while /-əz/ would only appear after voiced sibilants). This is the best analysis when the example is taken in isolation, because positing an epenthesis rule allows the phonological rules to be assumed to be productive across the entire lexicon of English. If such a fully productive deletion rule were posited, then it would be impossible to account for the pronunciation of a word like Paulas (‘multiple people named Paula’) with /-əz/ on the surface, whose underlying form would be exactly the same, phonologically, as Pauls (‘multiple people named Paul’). (This example only works if your plural suffix post-sibilant allomorph is /-əz/ rather than /-ɪz/, but a similar example could probably be exhibited in the other case.) One could appeal to the differing placement of the morpheme boundary but this is unappealing.

However, the assumption that a single epenthesis rule operating between sibilants is productive across the entire English lexicon has to be given up, because ‘s < is and ‘s < has have different allomorphs after sibilants! Either they are accounted for by two different lexically-conditioned epenthesis rules (which is a very unappealing model) or the allomorphs with the vowels are actually the underlying ones, and the allomorphs without the vowels are produced by a not phonologically-conditioned but at least (sort of) morphologically-conditioned deletion rule that elides fully reduced unstressed vowels (/ə/, /ɪ/) before word-final obstruents. This rule only applies in inflectional suffixes (e.g. lettuce and orchid are immune), and even there it does not apply unconditionally because the superlative suffix -est is immune to it. But this doesn’t bother me too much. One can argue that the superlative is kind of a marginal inflectional category, when you put it in the company of the plural, the possessive and the past tense.

A nice thing about the synchronic rule I’m proposing here is that it’s more or less exactly the same as the diachronic rule that produced the whole situation in the first place. The Old English nom./acc. pl., gen. sg., and past endings were, respectively, -as, -es, -aþ and -ede. In Middle English final schwa was elided unconditionally in absolute word-final position, while in word-final unstressed syllables where it was followed by a single obstruent it was gradually eliminated by a process of lexical diffusion from inflectional suffix to inflectional suffix, although “a full coverage of the process in ME is still outstanding” (Minkova 2013: 231). Even the superlative suffix was reduced to /-st/ by many speakers for a time, but eventually the schwa-ful form of this suffix prevailed.

I don’t see this as a coincidence. My inclination, when it comes to phonology, is to see the historical phonology as essential for understanding the present-day phonology. Synchronic phonological alternations are for the most part caused by sound changes, and trying to understand them without reference to these old sound changes is… well, you may be able to make some progress but it seems like it’d be much easier to make progress more quickly by trying to understand the things that cause them—sound changes—at the same time. This is a pretty tentative paragraph, and I’m aware I’d need a lot more elaboration to make a convincing case for this stance. But this is where my inclination is headed.

[1] The transcription system is the one which I prefer to use for my own accent of English.

References

Minkova, D. 2013. A Historical Phonology of English. Edinburgh University Press.

Advertisements

A language with no word-initial consonants

I was having a look at some of the squibs in Linguistic Inquiry today, which are often fairly interesting (and have the redeeming quality that, when they’re not interesting, they’re at least short), and there was an especially interesting one in the April 1970 (second ever) issue by R. M. W. Dixon (Dixon 1970) which I’d like to write about for the benefit of those who can’t access it.

In Olgolo, a variety of Kunjen spoken on the Cape York Peninsula, there appears to been a sound change that elided consonants in initial position. That is, not just consonants of a particular variety, but all consonants. As a result of this change, every word in the language begins with a vowel. Examples (transcriptions in IPA):

  • *báma ‘man’ > áb͡ma
  • *míɲa ‘animal’ > íɲa
  • *gúda ‘dog’ > úda
  • *gúman ‘thigh’ > úb͡man
  • *búŋa ‘sun’ > úg͡ŋa
  • *bíːɲa ‘aunt’ > íɲa
  • *gúyu ‘fish’ > úyu
  • *yúgu ‘tree, wood’ > úgu

(Being used to the conventions of Indo-Europeanists, I’m a little disturbed by the fact that Dixon doesn’t identify the linguistic proto-variety to which the proto-forms in these examples belong, nor does he cite cognates to back up his reconstruction. But I presume forms very similar to the proto-forms are found in nearby Paman languages. In fact, I know for a fact that the Uradhi word for ‘tree’ is /yúku/ because Black (1993) mentions it by way of illustrating the remarkable Uradhi phonological rule which inserts a phonetic [k] or [ŋ] after every vowel in utterance-final position. Utterance-final /yúku/ is by this means realized as [yúkuk] in Uradhi.)

(The pre-stopped nasals in some of these words [rather interesting segments in of themselves, but fairly widely attested, see the Wikipedia article] have arisen due to a sound change occurring before the word-initial consonant elision sound change, which pre-stopped nasals immediately after word-initial syllables containing a stop or *w followed by a short vowel. This would have helped mitigate the loss of contrast resulting from the word-initial consonant elision sound change a little, but only a little, and between e.g. the words for ‘animal’ and ‘aunt’ homophony was not averted because ‘aunt’ had an originally long vowel [which was shortened in Olgolo by yet another sound change].)

Dixon says Olgolo is the only language he’s heard of in which there are no word-initial consonants, although it’s possible that more have been discovered since 1970. However, there is a caveat to this statement: there are monoconsonantal prefixes that can be optionally added to most nouns, so that they have an initial consonant on the surface. There are at least four of these prefixes, /n-/, /w-/, /y-/ and /ŋ-/; however, every noun seems to only take a single one of these prefixes, so we can regard these three forms as lexically-conditioned allomorphs of a single prefix. The conditioning is in fact more precisely semantic: roughly, y- is added to nouns denoting fish, n- is added to nouns denoting other animals, and w- is added to nouns denoting various inanimates. The prefixes therefore identify ‘noun classes’ in a sense (although these are probably not noun classes in a strict sense because Dixon gives no indication that there are any agreement phenomena which involve them). The prefix ŋ- was only seen on a one word, /ɔ́jɟɔba/ ~ /ŋɔ́jɟɔba/ ‘wild yam’ and might be added to all nouns denoting fruits and vegetables, given that most Australian languages with noun classes have a noun class for fruits and vegetables, but there were no other such nouns in the dataset (Dixon only noticed the semantic conditioning after he left the field, so he didn’t have a chance to elicit any others). It must be emphasized, however, that these prefixes are entirely optional, and every noun which can have a prefix added to it can also be pronounced without the prefix. In addition some nouns, those denoting kin and body parts, appear to never take a prefix, although possibly this is just a limitation of the dataset given that their taking a prefix would be expected to be optional in any case. And words other than nouns, such as verbs, don’t take these prefixes at all.

Dixon hypothesizes that the y- and n- prefixes are reduced forms of /úyu/ ‘fish’ and /íɲa/ ‘animal’ respectively, while w- may be from /úgu/ ‘tree, wood’ or just an “unmarked” initial consonant (it’s not clear what Dixon means by this). These derivations are not unquestionable (for example, how do we get from /-ɲ-/ to /n-/ in the ‘animal’ prefix?) But it’s very plausible that the prefixes do originate in this way, even if the exact antedecent words are difficult to identify, because similar origins have been identified for noun class prefixes in other Australian languages (Dixon 1968, as cited by Dixon 1970). Just intuitively, it’s easy to see how nouns might come to be ever more frequently replaced by compounds of the dependent original noun and a term denoting a superset; cf. English koala ~ koala bear, oak ~ oak tree, gem ~ gemstone. In English these compounds are head-final but in other languages (e.g. Welsh) they are often head-initial, and presumably this would have to be the case in pre-Olgolo in order for the head elements to grammaticalize into noun class prefixes. The fact that the noun class prefixes are optional certainly suggests that the system is very much incipient, and still developing, and therefore of recent origin.

It might therefore be very interesting to see how the Olgolo language has changed after a century or so; we might be able to examine a noun class system as it develops in real time, with all of our modern equipment and techniques available to record each stage. It would also be very interesting to see how quickly this supposedly anomalous state of every word beginning with a vowel (in at least one of its freely-variant forms) is eliminated, especially since work on Australian language phonology since 1970 has established many other surprising findings about Australian syllable structure, including a language where the “basic’ syllable type appears to be VC rather than CV (Breen & Pensalfini 1999). Indeed, since Dixon wrote this paper 46 years ago Olgolo might have changed considerably already. Unfortunately, it might have changed in a somewhat more disappointing way. None of the citations of Dixon’s paper recorded by Google Scholar seem to examine Olgolo any further, and the documentation on Kunjen (the variety which includes Olgolo as a subvariety) recorded in the Australian Indigenous Languages Database isn’t particularly overwhelming. I can’t find a straight answer as to whether Kunjen is extinct today or not (never mind the Olgolo variety), but Dixon wasn’t optimistic about its future in 1970:

It would be instructive to study the development of Olgolo over the next few generations … Unfortunately, the language is at present spoken by only a handful of old people, and is bound to become extinct in the next decade or so.

References

Black, P. 1993 (post-print). Unusual syllable structure in the Kurtjar language of Australia. Retrieved from http://espace.cdu.edu.au/view/cdu:42522 on 26 September 2016.

Breen, G. & Pensalfini, R. 1999. Arrernte: A Language with No Syllable Onsets. Linguistic Inquiry 30 (1): 1-25.

Dixon, R. M. W. 1968. Noun Classes. Lingua 21: 104-125.

Dixon, R. M. W. 1970. Olgolo Syllable Structure and What They Are Doing about It. Linguistic Inquiry 1 (2): 273-276.

The insecurity of relative chronologies

One of the things historical linguists do is reconstruct relative chronologies: statements about whether one change in a language occurred before another change in the language. For example, in the history of English there was a change which raised the Middle English (ME) mid back vowel /oː/, so that it became high /uː/: boot, pronounced /boːt/ in Middle English, is now pronounced /buːt/. There was also a change which caused ME /oː/ to be reflected as short /ʊ/ before /k/ (among other consonants), so that book is now pronounced as /bʊk/. There are two possible relative chronologies of these changes: either the first happens before the second, or the second happens before the first. Now, because English has been well-recorded in writing for centuries, because these written records of the language often contain phonetic spellings, and because they also sometimes communicate observations about the language’s phonetics, we can date these changes quite precisely. The first probably began in the thirteenth century and continued through the fourteenth, while the second took place in the seventeenth century (Minkova 2015: 253-4, 272). In this particular case, then, no linguistic reasoning is needed to infer the relative chronology. But much of if not most of the time in historical linguistics, we are not so lucky, and are dealing with the history of languages for which written records in the desired time period are much less extensive, or completely nonexistent. Relative chronologies can still be inferred under these circumstances; however, it is a methodologically trickier business. In this post, I want to point out some complications associated with inferring relative chronologies under these circumstances which I’m not sure historical linguists are always aware of.

Let’s begin by thinking again about the English example I gave above. If English was an unwritten language, could we still infer that the /oː/ > /uː/ change happened before the /oː/ > /ʊ/ change? (I’m stating these changes as correspondences between Middle English and Modern English sounds—obviously if /oː/ > /uː/ happened first then the second change would operate on /uː/ rather than /oː/.) A first answer might go something along these lines: if the /oː/ > /uː/ change in quality happens first, then the second change is /uː/ > /ʊ/, so it’s one of quantity only (long to short). On the other hand, if /oː/ > /ʊ/ happens first we have a shift of both quantity and quality at the same time, followed by a second shift of quality. The first scenario is simpler, and therefore more likely.

Admittedly, it’s only somewhat more likely than the other scenario. It’s not absolutely proven to be the correct one. Of course we never have truly absolute proofs of anything, but I think there’s a good order of magnitude or so of difference between the likelihood of /oː/ > /uː/ happening first, if we ignore the evidence of the written records and accept this argument, and the likelihood of /oː/ > /uː/ happening first once we consider the evidence of the written records.

But in fact we can’t even say it’s more likely, because the argument is flawed! The /uː/ > /ʊ/ would involve some quality adjustment, because /ʊ/ is a little lower and more central than /uː/.[1] Now, in modern European languages, at least, it is very common for minor quality differences to exist between long and short vowels, and for lengthening and shortening changes to involve the expected minor shifts in quality as well (if you like, you can think of persistent rules existing along the lines of /u/ > /ʊ/ and /ʊː/ > /uː/, which are automatically applied after any lengthening or shortening rules to “adjust” their outputs). We might therefore say that this isn’t really a substantive quality shift; it’s just a minor adjustment concomitant with the quality shift. But sometimes, these quality adjustments following lengthening and shortening changes go in the opposite direction than might be expected based on etymology. For example, when /ʊ/ was affected by open syllable lengthening in Middle English, it became /oː/, not /uː/: OE wudu > ME wood /woːd/. This is not unexpected, because the quality difference between /uː/ and /ʊ/ is (or, more accurately, can be) such that /ʊ/ is about as close in quality to /oː/ as it is to /uː/. Given that /ʊ/ could lengthen into /oː/ in Middle English, it is hardly unbelievable that /oː/ could shorten into /ʊ/ as well.

I’m not trying to say that one should go the other way here, and conclude that /oː/ > /ʊ/ happened first. I’m just trying to argue that without the evidence of the written records, no relative chronological inference can be made here—not even an insecure-but-best-guess kind of relative chronological inference. To me this is surprising and somewhat disturbing, because when I first started thinking about it I was convinced that there were good intrinsic linguistic reasons for taking the /oː/ > /uː/-first scenario as the correct one. And this is something that happens with a lot of relative chronologies, once I start thinking about them properly.

Let’s now go to an example where there really is no written evidence to help us, and where my questioning of the general relative-chronological assumption might have real force. In Greek, the following two very well-known generalizations about the reflexes of Proto-Indo-European (PIE) forms can be made:

  1. The PIE voiced aspirated stops are reflected in Greek as voiceless aspirated stops in the general environment: PIE *bʰéroh2 ‘I bear’ > Greek φέρω, PIE *dʰéh₁tis ‘act of putting’ > Greek θέσις ‘placement’, PIE *ǵʰáns ‘goose’ > Greek χήν.
  2. However, in the specific environment before another PIE voiced aspirated stop in the onset of the immediately succeeding syllable, they are reflected as voiceless unaspirated stops: PIE *bʰeydʰoh2 ‘I trust’ > Greek πείθω ‘I convince’, PIE *dʰédʰeh1mi ‘I put’ > Greek τίθημι. This is known as Grassman’s Law. PIE *s (which usually became /h/ elsewhere) is elided in the same environment: PIE *segʰoh2 ‘I hold’ > Greek ἔχω ‘I have’ (note the smooth breathing diacritic).

On the face of it, the fact that Grassman’s Law produces voiceless unaspirated stops rather than voiced ones seems to indicate that it came into effect only after the sound change that devoiced the PIE voiced aspirated stops. For otherwise, the deaspiration of these voiced aspirated stops due to Grassman’s Law would have produced voiced unaspirated stops at first, and voiced unaspirated stops inherited from PIE, as in PIE *déḱm̥ ‘ten’ > Greek δέκα, were not devoiced.

However, if we think more closely about the phonetics of the segments involved, this is not quite as obvious. The PIE voiced aspirated stops could surely be more accurately described as breathy-voiced stops, like their presumed unaltered reflexes in modern Indo-Aryan languages. Breathy voice is essentially a kind of voice which is closer to voicelessness than voice normally is: the glottis is more open (or less tightly closed, or open at one part and not at another part) than it is when a modally voiced sound is articulated. Therefore it does not seem out of the question for breathy-voiced stops to deaspirate to voiceless stops if they are going to be deaspirated, in a similar manner as ME /ʊ/ becoming /oː/ when it lengthens. Granted, I don’t know of any attested parallels for such a shift. And in Sanskrit, in which a version of Grassman’s Law also applies, breathy-voiced stops certainly deaspirate to voiced stops: PIE *dʰédʰeh1mi ‘I put’ > Sanskrit dádhāmi. So the Grassman’s Law in Greek certainly has to be different in nature (and probably an entirely separate innovation) from the Grassman’s Law in Sanskrit.[2]

Another example of a commonly-accepted relative chronology which I think is highly questionable is the idea that Grimm’s Law comes into effect in Proto-Germanic before Verner’s Law does. To be honest, I’m not really sure what the rationale is for thinking this in the first place. Ringe (2006: 93) simply asserts that “Verner’s Law must have followed Grimm’s Law, since it operated on the outputs of Grimm’s Law”. This is unilluminating: certainly Verner’s Law only operates on voiceless fricatives in Ringe’s formulation of it, but Ringe does not justify his formulation of Verner’s Law as applying only to voiceless fricatives. In general, sound changes will appear to have operated on the outputs of a previous sound change if one assumes in the first place that the previous sound change comes first: the key to justifying the relative chronology properly is to think about what alternative formulations of each sound change are required in order to make the alternative chronology (such alternative formulations can almost always be formulated), and establish the high relative unnaturalness of the sound changes thus formulated compared to the sound changes as formulable under the relative chronology which one wishes to justify.

If the PIE voiceless stops at some point became aspirated (which seems very likely, given that fricativization of voiceless stops normally follows aspiration, and given that stops immediately after obstruents, in precisely the same environment that voiceless stops are unaspirated in modern Germanic languages, are not fricativized), then Verner’s Law, formulated as voicing of obstruents in the usual environments, followed by Grimm’s Law formulated in the usual manner, accounts perfectly well for the data. A Wikipedia editor objects, or at least raises the objection, that a formulation of the sound change so that it affects the voiceless fricatives, specifically, rather than the voiceless obstruents as a whole, would be preferable—but why? What matters is the naturalness of the sound change—how likely it is to happen in a language similar to the one under consideration—not the sizes of the categories in phonetic space that it refers to. Some categories are natural, some are unnatural, and this is not well correlated with size. Both fricatives and obstruents are, as far as I am aware, about equally natural categories.

I do have one misgiving with the Verner’s Law-first scenario, which is that I’m not aware of any attested sound changes involving intervocalic voicing of aspirated stops. Perhaps voiceless aspirated stops voice less easily than voiceless unaspirated stops. But Verner’s Law is not just intervocalic voicing, of course: it also interacts with the accent (precisely, it voices obstruents only after unaccented syllables). If one thinks of it as a matter of the association of voice with low tone, rather than of lenition, then voicing of aspirated stops might be a more believable possibility.

My point here is not so much about the specific examples; I am not aiming to actually convince people to abandon the specific relative chronologies questioned here (there are likely to be points I haven’t thought of). My point is to raise these questions in order to show at what level the justification of the relative chronology needs to be done. I expect that it is deeper than many people would think. It is also somewhat unsettling that it relies so much on theoretical assumptions about what kinds of sound changes are natural, which are often not well-established.

Are there any relative chronologies which are very secure? Well, there is another famous Indo-European sound law associated with a specific relative chronology which I think is secure. This is the “law of the palatals” in Sanskrit. In Sanskrit, PIE *e, *a and *o merge as a; but PIE *k/*g/*gʰ and *kʷ/*gʷ/*gʷʰ are reflected as c/j/h before PIE *e (and *i), and k/g/gh before PIE *a and *o (and *u). The only credible explanation for this, as far as I can see, is that an earlier sound change palatalizes the dorsal stops before *e and *i, and then a later sound change merges *e with *a and *o. If *e had already merged with *a and *o by the time the palatalization occurred, then the palatalization would have to occur before *a, and it would have to be sporadic: and sporadic changes are rare, but not impossible (this is the Neogrammarian hypothesis, in its watered-down form). But what really clinches it is this: that sporadic change would have to apply to dorsal stops before a set of instances of *a which just happened to be exactly the same as the set of instances of *a which reflect PIE *e, rather than *a or *o. This is astronomically unlikely, and one doesn’t need any theoretical assumptions to see this.[3]

Now the question I really want to answer here is: what exactly are the relevant differences in this relative chronology that distinguish it from the three more questionable ones I examined above, and allow us to infer it with high confidence (based on the unlikelihood of a sporadic change happening to appear conditioned by an eliminated contrast)? It’s not clear to me what they are. Something to do with how the vowel merger counterbleeds the palatalization? (I hope this is the correct relation. The concepts of (counter)bleeding and (counter)feeding are very confusing for me.) But I don’t think this is referring to the relevant things. Whether two phonological rules / sound changes (counter)bleed or (counter)feed each other is a function of the natures of the phonological rules / sound changes; but when we’re trying to establish relative chronologies we don’t know what the natures of the phonological rules / sound changes are! That has to wait until we’ve established the relative chronologies. I think that’s why I keep failing to compute whether there is also a counterbleeding in the other relative chronologies I talked about above: the question is non-well-formed. (In case you can’t tell, I’m starting to mostly think aloud in this paragraph.) What we do actually know are the correspondences between the mother language and the daughter language[4], so an answer to the question should state it in terms of those correspondences. Anyway, I think it is best to leave it here, for my readers to read and perhaps comment with their ideas, providing I’ve managed to communicate the question properly; I might make another post on this theme sometime if I manage to work out (or read) an answer that satisfies me.

Oh, but one last thing: is establishing the security of relative chronologies that important? I think it is quite important. For a start, relative chronological assumptions bear directly on assumptions about the natures of particular sound changes, and that means they affect our judgements of which types of sound changes are likely and which are not, which are of fundamental importance in historical phonology and perhaps of considerable importance in non-historical phonology as well (under e.g. the Evolutionary Phonology framework of Blevins 2004).[5] But perhaps even more importantly, they are important in establishing genetic linguistic relationships. Ringe & Eska (2014) emphasize in their chapter on subgrouping how much less likely it is for languages to share the same sequence of changes than the same unordered set of changes, and so how the establishment of secure relative chronologies is our saving grace when it comes to establishing subgroups in cases of quick diversification (where there might be only a few innovations common to a given subgroup). This seems reasonable, but if the relative chronologies are insecure and questionable, we have a problem (and the sequence of changes they cite as establishing the validity of the Germanic subgroup certainly contains some questionable relative chronologies—for example they have all three parts of Grimm’s Law in succession before Verner’s Law, but as explained above, Verner’s Law could have come before Grimm’s; the third part of Grimm’s Law may also have not happened separately from the first).

[1] This quality difference exists in present-day English for sure—modulo secondary quality shifts which have affected these vowels in some accents—and it can be extrapolated back into seventeenth-century English with reasonable certainty using the written records. If we are ignoring the evidence of the written records, we can postulate that the quality differentiation between long /uː/ and short /ʊ/ was even more recent than the /uː/ > /ʊ/ shift (which would now be better described as an /uː/ > /u/ shift). But the point is that such quality adjustment can happen, as explained in the rest of the paragraph.

[2] There is a lot of literature on Grassman’s Law, a lot of it dealing with relative chronological issues and, in particular, the question of whether Grassman’s Law can be considered a phonological rule that was already present in PIE. I have no idea why one would want to—there are certainly PIE forms inherited in Germanic that appear to have been unaffected by Grassman’s Law, as in PIE *bʰeydʰ- > English bide; but I’ve hardly read any of this literature. My contention here is only that the generally-accepted relative chronology of Grassman’s Law and the devoicing of the PIE voiced aspirated stops can be contested.

[3] One should bear in mind some subtleties though—for example, *e and *a might have gotten very, very phonetically similar, so that they were almost merged, before the palatalization occured. If one wants to rule out that scenario, one has to appeal again to the naturalness of the hypothesized sound changes. But as long as we are talking about the full merger of *e and *a we can confidently say that it occurred after palatalization.)

[4] Actually, in practice we don’t know these with certainty either, and the correspondences we postulate to some extent are influenced by our postulations about the natures of sound changes that have occurred and their relative chronologies… but I’ve been assuming they can be established more or less independently throughout these posts, and that seems a reasonable assumption most of the time.

[5] I realize I’ve been talking about phonological changes throughout this post, but obviously there are other kinds of linguistic changes, and relative chronologies of those changes can be established too. How far the discussion in this post applies outside of the phonological domain I will leave for you to think about.

References

Blevins, J. 2004. Evolutionary phonology: The emergence of sound patterns. Cambridge University Press.

Minkova, D. 2013. A historical phonology of English. Edinburgh University Press.

Ringe, D. 2006. A linguistic history of English: from Proto-Indo-European to Proto-Germanic. Oxford University Press.

Ringe, D. & Eska, J. F. 2013. Historical linguistics: toward a twenty-first century reintegration. Cambridge University Press.