Grasping numbers without words
Studies challenge theories that link language and thought
Brazil’s Pirahã people can’t count on using words for the number one or for any other number to describe exact quantities, a team led by MIT cognitive scientist Edward Gibson suggests (SN: 7/19/08, p. 5). The denizens of the Amazon rainforest are the first group anywhere reported to lack an expression for the number one. But Pirahã adults can still identify the number of items placed in front of them by picking out a matching number of items, the team concludes.
“These results suggest that number words do not change our underlying representations of number, but instead are a cognitive technology for keeping track of the exact size of large sets over time and in different contexts,” says study coauthor Michael Frank.
During testing, questions arose about whether the Pirahã really possessed nonverbal knowledge of precise amounts or simply assumed that they should place an item next to each item set out by experimenters. Gibson’s team plans to explore that possibility. In the meantime, the researchers have found that English speakers who are temporarily distracted and unable to count perform as well as the Pirahã do on tests requiring identification of up to 10 items (SN: 8/16/08, p.12). That’s further evidence that basic numerical competence operates nonverbally, without the need for counting terms, Frank says.