What is language?

There is nothing more central to human existence than language. We experience it every day of our conscious lives, and sometimes even in our dreams. Nonetheless, the biological nature of human language remains a largely unsolved puzzle for science, and many popular misunderstandings about language persist.

We may begin to answer the titular question by clarifying what language is not, pointing out what is universally and uniquely human about language, and finally sketching out the basic cognitive properties of language.

A common conception holds that language consists of words in a linear sequence, forming sentences like beads on a string. While this is an understandable belief, given the physical temporality of speech and writing, there is plentiful evidence that language is mentally represented as a hierarchical phrase structure composed of morphemes that are interpreted both semantically and phonologically in their phrasal context.

Such a scientifically informed view of language has numerous implications, and we will consider a few of special interest for students, who are the main target of companies pushing the rapid expansion of so-called ‚generative AI‘ or ‚Large Language Models‘.