Such a program, however, requires expertise in a number of different languages, research fields, and methodologies. Since we are investigating general principles which ought to hold for all languages, we need to consider how these principles apply to many languages, preferably as diverse as possible. However, as is well known, a correct analysis of any particular language cannot be obtained without close and detailed study. This is particularly true in our case, where we are interested not only in broad structural generalities such as can be obtained from a reference grammar, but also in the minutiae of phonetic details. It is only as a team that we could investigate so many language families, while still keeping our central concerns in sight.
Similar considerations hold with respect to research fields and methodology.
Though our primary focus is phonological theory, our interest is to find unifying principles which play a role in both segmental and prosodic domains. Prosodic structure interfaces with syntax, and we have explained elsewhere the role that phonetics plays in our theory. The study of learnability, however, requires different methods from conventional research in phonology, because of its mathematical and computational aspects.