In Language and Mind, Chomsky argues that all human languages share a core set of grammatical rules. He also posits that language acquisition is largely determined by innate factors. The book had a major impact on linguistics, cognitive science, philosophy, and politics. The reason why this book had such a significant impact is because Chomsky presented his theory of UG in a clear and concise way – to rephrase his point; he showed how all human languages share a set of grammatical rules, and how they are inherited from a common ancestor.
That is, human languages are not arbitrary; they are based on a set of rules that have been passed down through the generations. This means that the human brain is able to understand and use language based on a set of basic rules. How did these rules form and what did they do for human beings? This is a question that Chomsky was able to answer in the book.
Furthermore, Chomsky’s theory of UG helped solidify his reputation as one of the preeminent thinkers of his generation. UG is still used today to make sense of human language – it is short for Universal Grammar.