Linguistic relativity
The hypothesis of linguistic relativity holds that the structure of a language affects its speakers' world view or cognition. Also known as the Sapir–Whorf hypothesis, or Whorfianism, the principle is often defined to include two versions: the strong hypothesis and the weak hypothesis:

The strong version says that language determines thought and that linguistic categories limit and determine cognitive categories.
The weak version says that linguistic categories and usage only influence thought and decisions.The term "Sapir–Whorf hypothesis" is considered a misnomer by linguists for several reasons: Edward Sapir and Benjamin Lee Whorf never co-authored any works, and never stated their ideas in terms of a hypothesis. The distinction between a weak and a strong version of this hypothesis is also a later invention; Sapir and Whorf never set up such a dichotomy, although often in their writings their views of this relativity principle are phrased in stronger or weaker terms.The idea was first clearly expressed by 19th-century thinkers, such as Wilhelm von Humboldt, who saw language as the expression of the spirit of a nation.