The idea that the language we speak influences the way we think has evoked perennial fascination and intense controversy. According to the strong version of this hypothesis, called the Sapir-Whorf hypothesis after the American linguists who propounded it, languages vary in their semantic partitioning of the world, and the structure of one's language influences how one understands the world. Thus speakers of different languages perceive the world differently.

Although the last two decades have been marked by extreme skepticism concerning the possible effects of language on thought,...