The Entropy of Morphological Systems in Natural Languages Is Modulated by Functional and Semantic Properties

ABSTRACT

In most natural languages, grammatical gender and number features encode semantic attributes concerning animacy, sex, and numerosity. Despite the likely advantage of promptly communicating about such salient attributes, inflectional systems rarely display consistently bijective correspondences between the semantic attributes and the grammatical feature values. In a study on Italian, we explored how this apparently noisy encoding depends on a trade-off between the semantic and the functional aspects of grammatical features. Using entropy metrics, we assessed the primarily functional purpose of gender and number features in the lexicon, observing a distribution of nouns that can optimally serve agreement-based parsing and prediction of words in sentences. A novel context entropy measure, introduced in this study to assess meaning specificity, revealed a semantic underspecification in masculine and singular nouns denoting animate referents. We argue that underspecification is the hallmark of the particular type of information compression occurring in inflectional systems. In binary inflectional systems, one value specifically encodes a semantic attribute, while the other value does not encode any semantic information, and surfaces as a default for functional purposes. By providing an information-theoretical account of the role of grammatical features, we set the basis for a scientifically informed pursue of language inclusiveness.

Acknowledgments

We wish to thank Claudia Artiaco, Davide Crepaldi and Alessandro Treves for their insightful comments and fruitful discussion.

Disclosure Statement

No potential conflict of interest was reported by the author(s).

Notes

1. Languages differ in the way they encode kind references; in English, the generic interpretation of a kind can also be encoded in plurals (Lazaridou-Chatzigoga et al., 2017).

2. Some scholars have argued that prediction would instead be a waste of cognitive resources given the large number of nouns that may be suitable for occurring in any context (for a discussion cf., Van Petten & Luka, 2012). However, in the perspective of information theory (since Shannon, 1948), prediction does appear an efficient tool given noise occurring during communication (cf., Kleinschmidt & Jaeger, 2015).

3. For nouns denoting animate non-human referents, the oppositions likely denote the most frequent configurations of sex. For referents in higher positions in the animacy scales, including humans, attributes pertaining to the social and cultural construction of gender can be encoded as well. Notably, the latter varies across social and cultural groups and likely comprises more than two semantic attributes.

4. It is likely that, due to historical and societal configurations, human male referents in public roles are a majority; this may be reflected in the higher frequencies of occurrences of masculine forms. Even this case, though, can be economically described within an underspecification account. Indeed, the male referents cannot be denoted as specifically [+female], therefore the available grammatical value is masculine.