Noam Chomsky wrote a perfectly grammatical sentence that means literally nothing

In 1957 Chomsky offered 'Colorless green ideas sleep furiously' as flawless English grammar with zero meaning, to prove grammar and meaning are separate systems. He contrasted it with its word-for-word reversal, 'Furiously sleep ideas green colorless,' which is just as meaningless but also ungrammatical.

— Noam Chomsky, Syntactic Structures — Mouton, 1957
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