Determining cross-linguistic phonological similarity between segments: The primacy of abstract aspects of similarity

Although the general notion of "phonological similarity" has figured prominently in linguistic scholarship, the manner in which talkers determine similarity between phonological units is not well understood. Recent research has shown that perceptual similarity does not account for input-output mappings between languages as well as it does within a language. I argue that this disparity arises due to the fact that, unlike phonological similarity within a language, phonological similarity between languages is highly influenced by an abstract, between-system level of analysis that is only relevant cross-linguistically. I review an array of findings in cross-linguistic research to demonstrate, first, a dissociation between acoustic distance and phonemic correspondence and, second, a consistent preference for relating segments and natural classes cross-linguistically on the basis of phonemic correspondence. This type of abstract comparison helps to explain why effects of perceptual similarity are often masked in cross-linguistic circumstances, and I point to possible bases of these comparisons: (1) inventory niches based on contrastive feature oppositions and/or relative phonetics, and (2) distributional parallelisms