This view challenges much of the traditionally dominant thinking and practice in linguistic theory, from Ferdinand de Saussure to Noam Chomsky. Mainstream theorists do not deny the existence of variation, rather they tend to downplay its relevance and treat it as a superficial phenomenon obscuring a fundamental uniformity that characterizes language. Labov’s research demonstrates that linguistic variation is pervasive and highly structured, revealing regular patterns of co-occurrence between language forms, such as the pronunciation of a particular vowel, and social categories, such as socioeconomic classes.