The present paper is an attempt to show the origin, development and nature of Chomsky's linguistics. It will be indicated that Chomskyan linguistics is a Lakatosian research program which marks the beginning of the Second Cognitive Revolution. Therefore, its origin is the Rationalist thought of the seventeenth and eighteenth centuries. The nature of the program constitutes three problems, namely those of Humboldt's, Plato's and Descartes's and its development passes through two stages: rule-based and principle-based and three periods: derivational, representational and again derivational.

According to Chomsky's view, the main part of our linguistic knowledge is genetically determined. Therefore, language is inherent and this unknowing or tacit knowledge lies at the foundation of our ability to speak. The purpose of this article is to analyze the nature of tacit language in Chomsky's philosophy. This research is based on a qualitative research approach and conceptual analysis method to study the concept of tacit language and its relation with other main components of Chomsky's attitude toward language including linguistic competence, generative linguistics, universal grammar and argument of stimulus poverty. According to the three main critiques of tacit linguistic knowledge, tacit linguistic ability, and tacit linguistic rule, the tacit access to the reservoir of linguistic rules in the philosophy of Chomsky is not well explained and it is not empirically verifiable. Therefore, when this knowledge is valid, it is based on a kind of explicit language knowledge of grammar and rules which are expressed in the form of a statement and can be recognized and verified by the user of the language.

Translation is defined as the transfer of meaning from a language system into another without any change or reduction in meaning. Chomsky's model, as a framework for translation, would render meaning from SL D-structure into TL D-structure, but Chomsky's methodology in distinguishing competence from performance poses certain serious implications for transfer of meaning. D-structure is a level of conceptual meaning, containing simply those aspects of meaning which are lexicalized and which are incorporated in the D-structure through lexical registration rules. However, contextual meanings which are treated under pragmatics will be capable of transfer, unless they either are lexicalized both in SL and TL, or are arbitrarily represented in a word or lexical item in SL and TL.

The relationship between mind and language regarding Abdolqaher georgani and Noam Chomsky views Chomsky and Georgani emphasize on the necessity of documanents and adaptation of vocabulary on grammatical ryles regarding the definition of language. Based on Chimsky and Georgani is not only grammer but also the rules for language projuction in the mind the speaker، therefore، the expectation of the existence of the relationship between the instinctive properties of mind and language features seen really natural. This relationship regarding Georgani is limited to the product and comprehention of speech in the mind، but Chomsky seeks the identification of the neture of mind as the instinctive tablent and unique one through the ordering force in language. regarding the gramnatical rules، he doesn t separate the grammar، but in invatigting the comprehehension process and the analysis of sentence، he believes that the grammatical viwies for the speaker and litrer exist.

This study intends to analyze Guilaki prepositional constructions and to compare the results with Chomsky's ideas concerning Head Parameter. 1200 Fumani and Rashti participants, selected through stratified random sampling, were divided into twelve groups on the basis of their age, gender, literacy and locality. A list of 20 Guilaki sentences, taken from Christensen (1375/1995), was used after it was lexically and syntactically modified. Each sentence contained a blank to be filled in by an appropriate prepositional/postpositional construction. On the whole 24020 constructions were gathered and they were divided into four groups: PREP + NP, NP + POSTP, PREP +NP + POSTP, and finally NP. The findings revealed that in Guilaki Head Parameter is not binary but tertiary. In other words there are three types of constructions in Guilaki: PREP + NP, NP + POSTP, and PREP + NP + POSTP.

Verb valency is central to dependency grammar, but its role in generative grammar is ambiguous. The first theory gives a central role to verbs, determines certain groups of relations among the components of a sentence, and assumes free valence around key elements of a sentence, especially for verbs. The second theory is based on formal and relational structures of subject and predicate and assumes the generation of grammatical layers. The main objective of this study is to compare the two grammars to find out if Chomsky's sentential transformations are controlled by the concept of valency or not, and to discover how verbal valency affects the basic structure of a sentence and determines the surface structure. In order to answer these questions, the authors have first taken a look at new analytical and developmental views on Tesniè re's theory through examples. Then, by an analytical approach, the authors have provided a comparative study of Tesniè re and Chomsky's views. According to Tesniè re, speech acts like the translation of a “ linear system” into a “ syntactic system” . Conversely, the action of understanding in its turn acts like the translation of a syntactic system into a linear one. He differentiates between both and believes that the syntactic system is not necessarily linear. Moreover, by defining a concept of zero (free) valency, Tesniè re’ s approach is better able to explain the transformations and permutations in the sentences compared to Chomsky’ s approach. The concept of "universal sentence" in Chomsky’ s theory seeks to describe the abilities of language users in the production of complex sentences. By analyzing some examples in this study, the authors have shown that Chomsky’ s approach, which considers the transformations of a sentence as an ability of the main to accept additional ones, is more similar to Tesniè re’ s approach. Chomsky’ s theory, takes into accounts a free place for an additional syntagma to explain the development of the basic structure as well. So, this syntagmatic load resembles free valence in Tesniè re’ s theory. The results showed that as a dynamic system, language automatically creates free valence around or next to central elements and ultimately provides the possibility of certain grammatical transformations.