Sounds like he believed in The Sapir–Whorf hypothesis:
> The hypothesis of linguistic relativity, also known as the Sapir–Whorf hypothesis /səˌpɪər ˈwɔːrf/, the Whorf hypothesis, or Whorfianism, is a principle suggesting that the structure of a language affects its speakers' worldview or cognition, and thus people's perceptions are relative to their spoken language.
> Linguistic determinism is the concept that language and its structures limit and determine human knowledge or thought, as well as thought processes such as categorization, memory, and perception.
> The hypothesis of linguistic relativity, also known as the Sapir–Whorf hypothesis /səˌpɪər ˈwɔːrf/, the Whorf hypothesis, or Whorfianism, is a principle suggesting that the structure of a language affects its speakers' worldview or cognition, and thus people's perceptions are relative to their spoken language.
> Linguistic determinism is the concept that language and its structures limit and determine human knowledge or thought, as well as thought processes such as categorization, memory, and perception.