A Neo-Jakobsonian merger of aperture, [−atr], lowering, emphaticness, and retroflexion

I argue that the system of Standard Yoruba vowels and their harmonic behaviour follow directly from the internal structure of vowels assumed in Government Phonology 2.0, a theory which reinterprets aperture (openness) as empty structure. I address a common connection between aperture and [− atr ] and propose that while aperture is empty structure in general, [− atr ] is a particular position within that empty structure. As a result, both Yoruba vowel harmony as well as other typical limitations of [− atr ] (e.g. in high vowels) become derivable. What is more, the same reasoning (and the same solution) can be applied to the representation of consonants, in languages as diverse as French, Swedish, and Arabic, allowing me to unify (at least) aperture, [− atr ], lowering, emphaticness, and retroflexion.