My research philosophy
My research philosophy may be summed up in two phrases: Formal precision and Descriptive adequacy.
Descriptive adequacy. “Chaque langue est un système où tout se tient” (Meillet 1913); or, in Sapir’s words, each language has its own “structural genius” that underlies the “sundry facts” (Sapir 1921). Most linguistic work done today, however, looks only at bits and pieces of systems, rather than whole systems. Sometimes this atomistic approach is even argued for explicitly (McCarthy 2008: 31-32).
A descriptively adequate grammar is a grammar that generates all of the grammatical forms of a language, and excludes all of the ungrammatical ones (Chomsky 1964: 62-63). But how is descriptive adequacy to be evaluated? If we restrict our analysis only to a small part of a system, how can we distinguish between genuine counterexamples, i.e. those forms which the analysis has failed to explain, from those forms which are merely beyond the scope of the analysis? In fact, I believe this is impossible: analyses based on small data sets are always left with an element of uncertainty, since we don’t know what else is out there in the language. There is no descriptive adequacy without descriptive completeness.
Formal precision. While there has been much discussion in recent years on the need for empirical evidence to support theoretical claims (Wasow & Arnold 2005), an equally serious problem, in my view, is theoretical claims in the literature which are not clearly defined. How can we determine whether a claim is true or false, if it is stated in a vague or imprecise manner? Specifically, since the introduction of Optimality Theory (Prince & Smolensky 1993), it has become common practice to omit reference to any representational model. However, this often means that the resulting phonological analyses are poorly defined with unclear empirical predictions. This is because it is to representations that all OT constraints ultimately refer, and it is on the basis of these representations that constraint violations are ultimately computed.
For this reason I am rather conservative as a phonologist, having re-introduced a number of 1980’s style representational devices into my work: Lexical Phonology, Autosegmental Phonology, Feature Geometry, and, most recently, the Contrastive Hierarchy.
My work in phonetics is what might be called 'descriptive phonetics'--looking for instrumental evidence to verify the existence of phonological patterns in the language. For example, I did a phonetic study of the Wıìlıìdeh stress system, and found that the surface prosody was iambic (see here), and I also did a phonetic study of the Tetsǫ́t'ıné vowel system, where I found that the language has 8 different vowels in stems (see here). In general, with this type of phonetics, we get results which are 'wildly significant' (for example, p-values with up to 18 zeroes) because the effect sizes are so large.
In a European language, these kinds of questions would usually not even be worth asking, but when working with under-described languages, we cannot take anything for granted--often there are seemingly basic things about the language, including even the phoneme inventory, which are not firmly established. So fieldwork is really about building our understanding of a language 'from the ground up'.
There are two big questions that guide my work in phonology: (1) where is the boundary between phonology and morphology, and (2) where is the boundary between synchronic phonology and historical phonology? Dene languages are an excellent place to investigate these issues, since they exhibit a great deal of opaque morphophonemics--alternations which are, from a historical perspective 'on their way out' of the phonology. Eventually, all phonological processes reach the end of their 'life-cycle' as lexically listed allomorphy (Bermúdez-Otero 2015)--the question is, when and how?
The theoretical models I use provide us with principled criteria to address these questions. In Stratal OT, if two phonological processes interact opaquely within a stratum, then at least one of them is actually lexically listed allomorphy. Under the Contrastivist Hypothesis, if a phonological alternation requires reference to non-contrastive features, then it also most likely does not belong to the synchronic phonology. Even applying these criteria, we still find that Dene languages have a huge amount of phonology going on--which is why they are such a fun and exciting group of languages to work with.
I am interested in morphology at two different 'levels', so to speak. At a practical level, I make use of a version of the traditional Deneist (Athapaskanist) "Interrupted Synthesis" model, to describe how the Dene verb is put together: Verb Theme, Verb Base, and Inflection (e.g. Kari 1989) This is useful for writing descriptive grammars and dictionaries and making teaching materials. This model is still necessary even for someone who uses Lexical Phonology, since the reality is that, in Dene languages, phonological structure and morphological structure are non-isomorphic. The best way to reconcile the two models is to think of the Lexical Phonology model as operating on the output of the Interrupted Synthesis model.
At a higher level, I am interested in morphological typology, specifically Sapir's original typology of Isolating, Agglutinating, and Fusional languages (Sapir 1921), which at present does not seem to be recognized as such by any formal theory (Carstairs-McCarthy 1992: 166-167). Again, I think that Dene languages are an excellent place to investigate this question, since the verb morphology is generally in a transitional state between agglutinative and fusional, and the question of 'when do opaque phonological processes become morphologized?' is really the same question as 'when do separate, agglutinative prefixes become fused?' So the two sets of questions, phonological and morphological, are closely related as I see things.