In general linguistics Ferdinand de Saussure described a sign as a combination of a concept and a sound-image. A sound image is something mental as it is possible to talk to oneself without actually moving the lips. But normally the sound-images are used to produce an utterance.
So a sign consists of:
- a concept - respectively the signified (signifié)
- a sound-image - respectively the signifier (signifiant), or phonological form in generative terms..
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