Abstract: There are no unaspirated voiceless plosives in English, only unaspirated voiced plosives and aspirated voiceless plosives. All voiceless plosives in English are aspirated.
The standard theory we all learnt as undergrads tells us that English prevocalic voiceless plosives come in two flavors, aspirated when syllable initial and unaspirated otherwise. The standard theory we all learnt as undergrads can’t be right: it entails that voiced plosives cannot occur in syllable-second position. Such a prohibition a) has no justification and b) is absurd — the unaspirated voiceless plosives that the standard allophonic theory predicts do occur in that position sound just like voiced plosives. I’ve got two replacement theories to offer, neither perfect but both better than the standard.
The basic facts are these: a) English voiced plosives are unaspirated throughout the language; b) there is therefore no way to distinguish unaspirated voiceless plosives from voiced plosives in English — there is no difference in English between the sequences [skIl]; and [sgIl]: the word “skill” may as well be [s]+”gill” as [s]+”kill” with deaspiriation of the “k.” The former analysis is simpler — it requires no stipulation about deaspiration of /k/. English speakers’ bias towards the latter, more complex, analysis, reflects mere spelling convention. Yet the more complex, spelling-biased theory is the standard linguistics textbook theory.
Here’s the problem. The standard — spelling biased — theory has two rules:
1) voiceless aspirated prevocalic initials (e.g., “pill,” “till” and “kill”) are deaspirated when preceded by [s];
2) [b], [d] and [g] never occur preceded by [s] and followed by a vowel (they never occur in the deaspiration environment of 1).
On this theory, the phonemes /p/, /t/ and /k/ have two rule-governed allophonic pronunciations in prevocalic position: aspirated (syllable initial) and unaspirated (preceded by [s]).
Rule (1) is pedagogically useful for teaching the notion of the phoneme, complementary distribution and the allophone to students in their first exposure to linguistics. That may be why it persists. It has the unfortunate consequence of interpreting all plosives wedged between [s] and a vowel as deaspirated voiceless consonants, leaving no room for voiced plosives in that position. And there is no natural justification for a prohibition on voiced plosives in this position. Why shouldn’t the phonemes /b/, /d/ and /g/ occur there? After all, unaspirated /p/, /t/ and /k/ occur there and they sound exactly like [b], [d] and [g]. The prohibition is patently counterfactual: it says voiced plosives can’t occur in exactly the environment in which they do occur. This is not merely unjustifiable; it is preposterous.
A Simplest Answer
Consider a simpler theory without allophones: /p/, /t/ and /k/ are pronounced as aspirated [p], [t] and [k] wherever they are fully articulated; they are prohibited from occurring in the syllable second position by a double aspiration rule that is generally true of English consonant sequences. [fs] in Russian, not in English. There are only four English words with syllable initial double sequential aspirations and they are all Greek borrowings: sphere, sphinx, sphincter and sphalerite. I don’t know anyone but me who pronounces the labiodental initial of “phthisic” — but, then, I don’t know anyone else who pronounces the word at all. Even the lexicographers have dropped the [f]. Sequential onset aspiration is a foreign imposition on the natural phonology of English. This holds even in coda position: the aspirated /k/ of “ask” loses its aspiration when followed by a vowel (”ask anyone”).
This theory is considerably simpler and better than the standard. There’s only one rule, that rule has some natural justification and it does not lead to the standard’s absurdity. The rule: no voiceless plosives following [s] and preceding a vowel.
On this theory, in the onset /g/ is [g] and /k/ is [kh]. No allophones, no need, even, for phonemes. What you hear is what you get. It’s all phonetic, not phonological. If you want a justification for phonemes and allophones and complementary distribution, you have to look at environments where the plosives are not fully articulated. For example, the aspiration of /k/ is absorbed by [s] in “text” ([tEkst]); the /t/ loses is aspiration when followed by a vowel (”textile” — USA pronunciation, not where it’s divided into “tex”+”tile”) and the /t/ reduces to zero when followed by a consonant in “textbook.” These should suffice to serve the pedagogical function of introducing the notion of complimentary distribution, the phoneme and allophony.
A Problem for the Simple One-Rule Theory
There’s a serious problem with this theory. Consider “discourage.” On the standard theory, “courage” is underlyingly represented with an initial /k/ phoneme. Under the standard theory, allophonic variation in /k/ is induced by the presence of a syllable initial [s]. So, under the standard theory, “discourage” and “courage” are both represented with an underlying /k/ phoneme.
But under the simple theory, /k/ is prohibited from occurring after the [s]. These two words have different underlying representations, “courage” with a /k/ and “discourage” with a /g/.
Now, it does happen that morphology sometimes violates phonology. For example, the plural of “text” is required under English morphology to violate the syllable structure and consonant cluster constraints of English. Outside of such plurals and 3rd person singulars, English doesn’t permit consonant clusters of such length as [ksts] and any such concatenation of sounds would require division into two syllables.
An Unwelcome Solution
But the title of this entry refers to “Three Theories” so we’ve still got one to go.
Here’s a hybrid theory. Voiceless plosives become voiced when preceded by [s] and followed by a vowel. Here’s how this theory works:
The voiceless plosives share an allophone with the voiced plosives. /k/ and /g/, for example, are two distinct phonemes, but /k/ is sometimes pronounced the same as the /g/ phoneme is pronounced. So the underlying representation of “courage” and “discourage” both have the /k/, but in “courage” it is pronounced as an aspirated voiceless plosive, in “discourage” it is pronounced as a voiced plosive.
On this theory, there is no prohibition rule. Voiced plosives may appear before a vowel following [s]. So may voiceless plosives, but only in their unaspirated, voiced form.
Here is the unwelcome consequence: there is no way to determine on this theory whether “skill” has an underlying /k/ or an underlying /g/. In addition, the allophony requires a feature-changing rule and who really likes a feature-changing rule? Nobody talks to them at parties.
Cast in a more contemporary theory that regards features rather than phonemes, the three theories look like this:
Standard — plosives have place and voice features, but pick up aspiration by rule.
Simple — plosives are specified for place, voice and (redundantly) aspiration.
Unwelcome — plosives are specified for place and voice, but change voicing by rule.
The standard theory entails a preposterous prohibition. The simple theory entails changing underlying representations of identical morphemes. The unwelcome theory has a feature-changing rule. Take your pick.
The simplest analysis of “skill” under the unwelcome theory is [s]+/g/ — it requires fewer rules. But the theory already contains the feature-changing rule, so the more complex analysis is not ruled out even for economy’s sake. One may, however, assume that, ceteris paribus, a [g] is a /g/.