Linguistic Relativity

Linguistic relativity — the Sapir–Whorf hypothesis — proposes that the language a person speaks shapes how they think. It comes in a strong form, that language determines thought and makes some concepts unthinkable, and a weak form, that language influences attention and habitual categorisation.

The strong form is not supported. The weak form has modest experimental support: speakers of languages with different colour-term boundaries show small differences in discrimination speed, and languages using absolute rather than relative spatial terms produce speakers with markedly better absolute orientation. These are real, and they are effects on habit and attention rather than on capacity.

The debate's most-cited case is Pirahã, a language isolate of the Brazilian Amazon, reported to lack number words, colour terms, and recursive embedding. The claims are contested on both descriptive and interpretive grounds, and the fact worth extracting is methodological rather than linguistic: the evidence rests heavily on one researcher's fieldwork with a very small community, which is exactly the situation in which a claim should be held loosely.

The general lesson generalises past linguistics. A hypothesis that is interesting, widely repeated, and resting on a thin evidential base is the kind most likely to be believed past what it can support. See Plausible Mechanism and Exhaustive Claim.