 Hello, nice to see you. In the mid-20th century, the American linguist Noam Chomsky proposed a theory that our brains are hardwired with a mental template for learning grammar and that we rely on this innate grammar module to acquire language. His theory of universal grammar would endeavor to define a set of rules applicable to all languages, essentially exposing a hidden unity that underlies the vast surface diversity of the 7000 languages in the world. Universal grammar was a radical break from the more informal approaches prevalent at the time. Traditional approaches relied too much on the intelligent of the speaker and failed to account for a number of linguistic phenomena. Structuralist approaches had too limited a scope, focused too much on morphemes and phonemes and didn't account for the intelligence of the speaker. In his book Aspects of the Theory of Syntax, Chomsky drew attention to all the complexities involved in becoming a competent speaker of a language. His first version of the theory of universal grammar incorporated two emerging trends in Western intellectual life. The idea is that language had both a computational structure and was rooted in human biology. He posited that the language we use to communicate in everyday life behaves in the same manner as mathematically based computer languages. Simultaneously, he suggested that universal grammar was an innate component of the human mind with deep biological underpinnings. Universal grammar of the 1960s was initially based on the underlying structure of the languages spoken by those linguists who were developing the theory that meant, for the most part, European languages. The universal grammar program operated on chunks of language such as noun and verb phrases and sought to define rules that could be applied to or transform those phrases. However, exceptions that did not align with the established schema began to emerge, challenging this early idea of a universal grammar. Ergative languages such as Busk and Urdu, for example, use sentence subjects in a way that is unlike that in many European languages. Additionally, native Australian languages such as Walpiri scatter noun and verb phrases throughout the sentence. These outliers were difficult to reconcile with the universal grammar approach and led to a wholesale revision of the theory in the 1980s. Rather than a single universal grammar, for all the world's languages, the new version of the theory set to identify universal principles such as any structure X must have the property Y plus parameters that govern the structure of languages. These principles manifested themselves differently in each language and interacted with culture to produce today's parametric variations. Let us look at a non-linguistic example to illustrate this principles and parameters approach. The principle that could be found in our world is that all countries have roads that can be driven on. The question is on which side? So here we have a parameter that can be associated with each country, plus right for right-hand traffic and minus right for left-hand traffic. Here is a linguistic principle. Other declarative sentences normally have an overt subject, even if the subject is a pronoun. This is true for English and German, where sentences without the pronominal subject are ungrammatical. Languages such as Italian or Spanish by contrast can form fully grammatical sentences without the need for separate subjects. This parameter has become known as the pro-drop parameter. Some people also call it null-subject parameter. It is set minus for English and German, where the pronoun cannot be dropped, and plus for Italian and Spanish. The idea is, as soon as children encounter few sentences of this type, this pro-drop parameter would be set, and the children would know whether they could drop the subject in these sentences or not. The most recent revision of Universal Grammar came in 2002, when Chomsky and his colleagues published a paper in Science, where they described Universal Grammar that included only one feature called computational recursion or merge. This new shift in the paradigm permitted a limited number of words and rules to be combined to make an unlimited number of sentences. He also proposed that this recursive ability that may have arisen from a single genetic mutation between 100,000 and 50,000 years ago is what sets language apart from other types of cognitive processes, such as categorization and relational perception. However, as with the 1960 version of this theory, there is a counter example, the Amazonian language Pidaha. This language does not exhibit recursive structures. Defenders of Universal Grammar make the analogy that the universal parameters and principles are like our senses of taste. While culture and geography may produce variations in worldly cuisines, we are all nevertheless born with a basic set of tastes, sweet, sour, salty, bitter, and so on. Just because a culture lacks salt to season food does not mean that the members of that culture lack the ability to taste salt. Likewise, they would say just because a language lacks recursive structures, this does not mean that the speakers of that language lack the potential for recursion. This line of thinking makes Universal Grammar difficult to test in practice and contributes to the overall empirical inadequacies of the theory. Many researchers are becoming increasingly dissatisfied with a completely formal language approach such as Universal Grammar. With more and more evidence rebutting Chomsky's theory, a paradigm shift may be underway. This paradigm shift will be discussed in a second video on Universal Grammar. Until then, have a nice time and thanks for your attention.