Noam Chomsky, a prominent linguist, proposed the Language Acquisition Device (LAD) as a hypothetical mechanism in the brain that allows children to acquire language. According to Chomsky, children are born with the innate ability to acquire language, and the LAD is what enables them to do so. He suggested that the LAD contains a set of universal principles that are common to all human languages, and that these principles allow children to acquire language through exposure and interaction with adults. Chomsky argued that the LAD allows children to learn language without explicit instruction, and that it plays a crucial role in language development.

His theory has been both influential and controversial in the field of linguistics, and it has led to further research on the cognitive processes involved in language acquisition.