Leonard Bloomfield founded American structuralism, based on structural linguistics developed by Saussure. Bloomfield is known for applying the principles of behaviorist psychology to linguistics, defining "the meaning of a linguistic form as the situation in which the speaker utters it, and the response it calls forth in the hearer." (Oller, 1979).
His 1933 book Language is the classical structuralist text, setting out Bloomfield's rigorously empiricist approach to language study.
In his 1942 guide for second language learners, he advocated a blank slate approach:
The sounds, constructions, and meanings of different languages are not the same: to get an easy command of a foreign language one must learn to ignore the features of any and all other languages, especially of one's own.
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