The psychology of perception seems to suggest the existence of a common cognitive system which treats all or most sensorily conveyed meanings in the same way. If all signs must also be objects of perception, there is every reason to believe that their modality will determine at least part of their nature. Thus, the sensory modalities will be visual, auditory, tactile, olfactory, kinetic, etc. A list of sign types would include: text, symbol, index, image, map, graph, diagram, etc. Some combinations of signs can be multi-modal, i.e. different ...

See also:

Modality semiotics, Modality semiotics - Discussion of sign-type, Modality semiotics - Discussion of reality status

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