T he linguistic sign is more of a process than a thing. A sound pattern is the hearer's psychological impression of a sound. In this way, the character the linguistic sign is far less trivial than it seems at first. I t is the link between the signal and the signification that comprises the sign. The distinction is subtle, but also far from trivial in its implications.
Some explanation is necessary.
The linguistic sign is a useful device in the explanation of language, but it does not represent the totality of language, the object of study. Additionally, that system should contain all of the basic sound-meaning pairings contained in the language. These are the other signs of the language. It would be to suppose that a start could be made with individual signs, and a system constructed by putting them together. On the contrary, the system as a united whole is the starting point, from which it becomes possible, by a process of analysis, to identify its constituent elements.