"Colorless green ideas sleep furiously" is a sentence composed by Noam Chomsky in his 1957 Syntactic Structures as an example of a sentence that is grammatically correct (logical form) but semantically nonsensical. The term was originally used in his 1955 thesis "Logical Structures of Linguistic Theory". Although the sentence is grammatically correct, no obvious understandable meaning can be derived from it, and thus it demonstrates the distinction between syntax and semantics. As an example of a category mistake, it was used to show inadequacy of the then-popular probabilistic models of grammar, and the need for more structured models.
Read more about Colorless Green Ideas Sleep Furiously: Details, Attempts At Meaningful Interpretations, Statistical Challenges, Related and Similar Examples
Famous quotes containing the words green, ideas and/or sleep:
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From his toppling tansy-throne
In the green tempestuous land—”
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As I rode to sleep the owls were bearing the farm away,”
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