"Thought and language are distinct and autonomous in speaking, listening, reading and writing. Furthermore, thought is central and language is a symbolic system that we use to refer in various ways to what we think."" Robert Lado .
Ferdinand de Saussure, a Swiss linguist, was one of the founders of modern linguistics. He established the structural study of language, emphasizing the arbitrary relationship of the linguistic sign to that which it signifies. Saussure distinguished synchronic linguistics (studying language at a given moment) from diachronic linguistics (studying the changing state of a language over time). He perferred what he named langue (the state of a language at a certain time) to parole (the speech of an individual). Saussure's most influential work is the Course in General Linguistics (1916), a compilation of notes on his lectures.
His views revolutionized the study of language and inaugurated modern linguistics. His theory also has profoundly influenced other disciplines, especially anthropology, sociology, and literary criticism. The central belief of structuralism is that the phenomena of human life, whether language or media, are not intelligible except through their network of relationships, making the sign and the system (or structure) in which the sign is embedded primary concepts. As such, a sign "for instance, a word "gets its meaning only in relation to or in contrast with other signs in a system of signs.
David Holdcroft in his book, Saussure: Sign, System, and Arbitrariness, clearly states the two central ideas in Saussure's Language as a System of Signs': " Saussure introduces two key principles, the Arbitrary Nature of the sign and the Linear Nature of the Signifier- (47).
In general, the signifier and the signified are the components of the sign, which is formed by the associative link between the signifier and signified. Even with these two components, however, signs can exist only in opposition to other signs.