The assumption of the autonomy of syntax can be traced back to the neglect of the study of semantics by American structuralists like
Leonard Bloomfield and
Zellig Harris in the 1940s, which was based on a
neo-positivist anti-psychologist stance, according to which since it is presumably impossible to study how the brain works, linguists should ignore all cognitive and psychological aspects of language and focus on the only objective data, that is how language appears in its exterior form. This paralleled the distinction between the two approaches in psychology,
behaviorism, which was the dominant approach up until the 1940s, and
cognitivism. Over the decades, multiple instances have been found of cases in which syntactic structures are actually determined or influenced by semantic traits, and some formalists and generativists have reacted to that by shrinking those parts of semantics that they consider autonomous. Over the decades, in the changes that
Noam Chomsky has made to his generative formulation, there has been a shift from a claim for the autonomy of syntax to one for the autonomy of
grammar. == Functionalist linguistics vs. formalist linguistics ==