When money changes grammar: A comparative study of Chadic languages

The ancestors of speakers of Chadic languages entered the Sahel region around 7,000 years ago, and developed their languages in a context where commerce was predominately done through trading goods.

At some point in the last few millennia, the use of currency became the dominant mode of commerce, and speakers of Chadic languages began adapting to a new cognitive distinction: framing an exchange in terms of which party gives or receives money (BUY vs SELL). By comparing descriptions of 85 of the 200 Chadic languages spoken today, we can see diverse strategies employed to integrate the concepts of BUY and SELL in each grammar. One common strategy is to incorporate a new verb stem to express SELL, either through borrowing or semantic shift. The other common strategy is to co-opt existing verbal morphology to modify the verb meaning `trade’ and designate the modified form as SELL. Within the second strategy, there is a significant amount of variation in which verbal affixes are used to mark the SELL form. Some linguists have attempted to incorporate these SELL verbs into a compositional analysis of the meanings of verbal morphology of a particular language, but from a cross-linguistic perspective it becomes clear that the meaning of these particular complex verbs cannot be decomposed in a predictable manner, despite the use of the same morphology in predictable ways elsewhere in the language