Noam Chomsky is an influential American linguist known for developing the theory of transformational grammar and the theory of universal grammar. He proposed the existence of an innate language acquisition device (LAD) that contains the fundamental rules of grammar and allows children to rapidly acquire language abilities. The LAD hypothesizes that humans are born with an understanding of basic linguistic concepts like nouns and verbs. While the specific neurological basis of the LAD is theoretical, Chomsky's work contributed to the field of cognitive science and theories of innate linguistic knowledge.

2. Noam Chomsky
 Avram Noam Chomsky (born December 7, 1928) is an
American linguist, philosopher, cognitive scientist,
historian, social critic and political activist.
 Sometimes described as "the father of modern
linguistics", and one of the founders of the field of
cognitive science.
 He developed the theory of transformational grammar; for
this, he was awarded his doctorate in 1955.
 Chomsky is credited as the creator or co-creator of the
universal grammar theory, the generative grammar theory,
the Chomsky hierarchy, and the minimalist program.

3. LANGUAGELEARNING BY INTERACTION

4. What Is the Language Acquisition Device?
 Anybody who has had or known a child knows that children take to learning
language at a remarkable rate. In fact, it seemed a little too remarkable for one
linguistics researcher.
 Noam Chomsky,put forth an idea called the language acquisition device or LAD,
for short.
 The LAD is a hypothetical tool hardwired into the brain that helps children rapidly
learn and understand language.
 Chomsky used it to explain just how amazingly children are able to acquire
language abilities as well as accounting for the innate understanding of grammar
and syntax all children possess.

5. • Keep in mind that the LAD is a theoretical concept.
• There isn't a section of the brain with 'language acquisition device' printed on it
and a big switch to turn on and learn a new language.
• Rather, the LAD is used to explain what are most likely hundreds or thousands
of underlying processes that humans have in their brains that have evolved to
make us particularly exceptional at learning and understanding language.
• Chomsky developed the LAD in the 1950s, and since then, has moved on to a
greater theory called universal grammar (or UG) to account for the rapid
language development in humans.

6. Let's go into a little more detail on the LAD.
 Chomsky proposed that every child was born with an LAD that holds the
fundamental rules for language. In other words, children are born with an
understanding of the rules of language; they simply need to acquire the vocabulary.
 Chomsky offered a number of pieces of evidence to support his theory. He posed
that language is fundamentally similar across all of humanity. For instance, every
language has something that is like a noun and a verb, and every language has the
ability to make things positive or negative.
 Chomsky also discovered that when children are learning to speak, they don't make
the errors you would expect. For instance, children seem to understand that all
sentences should have the structure 'subject-verb-object', even before they are able to
speak in full sentences.

7.  From his experiments, Dr. Chomsky also noted that
young children, well before reaching language fluency,
would notice if adults around them spoke in a
grammatically incorrect manner.
 He also found that children attempt to apply grammatical
rules to words for which their language makes an
exception.
 For example, in following the English rules of grammar,
a child might pluralize the word 'fish' as 'fishes' and 'deer'
as 'deers', even though our language makes exceptions for
those words.

9.  Universal grammar (UG) in linguistics, is the theory of the genetic
component of the language faculty, usually credited to Noam Chomsky.
 The basic postulate of UG is that a certain set of structural rules are
innate to humans, independent of sensory experience. With more
linguistic stimuli received in the course of psychological development,
children then adopt specific syntactic rules that conform to UG. It is
sometimes known as "mental grammar", and stands contrasted with
other "grammars", e.g. prescriptive, descriptive and pedagogical.

10. Argument
The theory of universal grammar proposes that if human beings are brought up
under normal conditions, then they will always develop language with certain
properties (e.g., distinguishing nouns from verbs, or distinguishing function words
from content words).
The theory proposes that there is an innate, genetically determined language
faculty that knows these rules, making it easier and faster for children to learn to
speak than it otherwise would be.
This faculty does not know the vocabulary of any particular language, and there
remain several parameters which can vary freely among languages (such as
whether adjectives come before or after nouns) which must also be learned.

13. CHOMSKY’S THEORY
Chomsky argued that the human brain contains a limited set of
constraints for organizing language. This implies in turn that all
languages have a common structural basis: the set of rules known
as "universal grammar".
Speakers proficient in a language know which expressions are
acceptable in their language and which are unacceptable.
The key puzzle is how speakers come to know these restrictions
of their language, since expressions that violate those restrictions
are not present in the input.

14. CRITICISMS
Hinzen summarizes the most common criticisms of universal grammar:
a) • Universal grammar has no coherent formulation and is indeed unnecessary.
b) • Universal grammar is in conflict with biology: it cannot have evolved by
standardly accepted neo-Darwinian evolutionary principles.
c) • There are no linguistic universals: universal grammar is refuted by abundant
variation at all levels of linguistic organization, which lies at the heart of human
faculty of language