Whorf is best known as the main proponent of what he called the principle of linguistic relativity, but which is often known as "the Sapir–Whorf hypothesis", named for him and Edward Sapir. Whorf never stated the principle in the form of a hypothesis, and the idea that linguistic categories influence perception and cognition was shared by many other scholars before him. But because Whorf, in his articles, gave specific examples of how he saw the grammatical categories of specific languages related to conceptual and behavioral patterns, he pointed towards an empirical research program that has been taken up by subsequent scholars, and which is often called "Sapir–Whorf studies".