Abstract
Is exact number a human universal? Cross-cultural fieldwork has given strong evidence that language for exact number is an invention which is not present in all societies. This result suggests a range of questions about how learning an exact number system may interact with pre-existing analog magnitude representations. More generally, number presents a tractable case of the Whorfian question of whether speakers of different languages differ in their cognition. We addressed these questions by studying the performance of the Pirahã, an Amazonian group in Brazil, on a range of simple quantity matching tasks (first used by Gordon, 2004). We compared the performance of this group to the performance of English-speakers who were unable to use exact numerical representations due to a concurrent verbal interference task. We found that both groups were able to complete simple one-to-one matching tasks even without words for numbers and both groups relied on analog magnitude representations when faced with a more difficult task in which items in the set to be estimated were presented one at a time. However, performance between the two groups diverged on tasks in which other strategies could be used. We conclude that language for number is a “cognitive technology” which allows the manipulation of exact quantities across time, space, and changes in modality, but does not eliminate or substantially alter users' underlying numerical abilities.