The nature of human language is a defining feature of our species, setting us apart from all other forms of animal communication. Linguistics, the scientific study of language, begins by identifying the core properties that make human language uniquely powerful and flexible.
First among these is **productivity** (or creativity). Human speakers can generate and understand an infinite number of novel sentences, including ones never before uttered. You likely have never heard “The invisible kangaroo recited Shakespeare beneath a waterfall,” yet you comprehend it instantly. No animal communication system approaches this open-ended capacity.
Second is **displacement**. Language allows us to refer to things not present in space or time—yesterday’s mistakes, tomorrow’s hopes, fictional worlds, abstract concepts like justice or freedom. A bee can dance to indicate a nearby nectar source but cannot discuss last week’s harvest or plan for next season.
Third is **arbitrariness**. The relationship between a word’s form and its meaning is generally arbitrary: there is nothing inherently “tree-like” about the sound sequence /triː/. Different languages assign entirely different forms to the same concept. Exceptions like onomatopoeia (“buzz,” “splash”) are rare and vary across languages.
Fourth is **duality of patterning**. Language operates on two levels simultaneously: a finite set of meaningless sounds (phonemes) combines into meaningful units (morphemes, words), which then combine into infinite sentences. The same /p/ sound that distinguishes “pat” from “bat” appears in thousands of words—a remarkable economy.
Fifth is **cultural transmission**. Language is not wholly innate but acquired through social interaction. A newborn Japanese infant adopted into an Arabic-speaking family will grow up speaking fluent Arabic, not Japanese. The capacity for language is biological; the specific language is cultural.
Sixth is **discreteness**. Language is built from distinct, interchangeable units. Changing one sound—/b/ to /p/—changes meaning entirely. There are no gradual gradations between “bet” and “pet.”
Finally, **reflexiveness** allows us to use language to talk about language itself—to analyze grammar, define words, or discuss pronunciation.
Phonetics, the study of speech sounds, examines the physical raw material—how sounds are produced by the vocal tract and perceived by the ear—that enables these remarkable properties. Understanding language’s nature is the essential first step for all further linguistic inquiry.