The duality of patterning refers to the way in which speech can be broken down into meaningful components, which can then be further divided into meaningless elements.

Higher levels of organization (including morphology, syntax, and semantics) govern the combination of these individually meaningless phonemes into meaningful elements.

According to Charles F. Hockett and other linguists, this duality (a finite number of elements combining to produce an infinite number of meaning) is a crucial property of human languages as it allows the expression of an infinite number of meaningful language structures.
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