The document discusses different theories about language acquisition and the modularity of the mind. It compares Piaget's view that language develops through constructive stages to Chomsky's view that humans have an innate Universal Grammar. It also covers Fodor's Modularity Theory, which argues the mind is made up of specialized domain-specific modules rather than being domain-general. Finally, it provides an overview of Chomsky's view that the Faculty of Language in the mind, including the Universal Grammar and linguistic competence, are modular and allow children to acquire language during a critical period in development.