Fig. 1-3 Speech in numbness, language in gesture—Shakespeare
Have you heard of BODY LANGUAGE? The way we use our bodies in sitting, standing, walking, is considered to be expressive of our feelings and emotions and other meanings. Is it language? Let's consider from the basic properties:
First of all, body language lacks DUALITY. By this we mean it is not symbolic but rather a direct representation of a feeling. There is no "alphabet" of distinctive movements or postures. It lacks productivity, in that "original" expressions are likely not to be understood. Moreover, many movements or postures are often selected by their "meaning" as representational, not arbitrary. For instance, "barrier signs" such as crossing one's arms or legs need no dictionary. (Clark et at, 1985: 7) Can you think of some postures that are arbitrary in meaning? What about putting hands on each side of the waist?
How about "the language of traffic lights", "the language of ballet", "the language of music", and "the language of movie"? SEMIOTICS—a general science of signs—may be a more suitable field for studying these aspects. In semiotics, of course, human languages take the central position. So linguistics—the study of language can be a good start for you to go on exploring other semiotic systems.