Diachronic effects of rhinoglottophilia, symmetries in sound change, and the curious case of Basque

The particular affinity linking glottality and nasality to each other, a connection which is grounded both on articulatory and acoustic bases, seems to be responsible for various phonetic phenomena in different languages. In sound changes associated to what has been termed rhinoglottophilia (Matisoff 1975), the two logically possible diachronic pathways show up: from glottality to secondary nasalization, on the one hand, and from nasality to secondary laryngealization, on the other. The innovations concerned can thus be considered symmetrical, a feature that is rarely found in sound change. This paper first reviews the evidence at our disposal for positing a class of replacive phonetic changes caused by rhinoglottophilia, and then argues for an explanation of the diachronic correspondence n > h in the history of the Basque language based on the (primarily acoustic) effects of this specific connection between glottality (more specifically, aspiration) and nasality.