Modality (semiotics)

In semiotics, a modality is a particular way in which information is to be encoded for presentation to humans, i.e. to the type of sign and to the status of reality ascribed to or claimed by a sign, text or genre. It is more closely associated with the semiotics of Charles Peirce (1839–1914) than Ferdinand de Saussure (1857–1913) because meaning is conceived as an effect of a set of signs. In the Peircean model, a reference is made to an object when the sign (or representamen) is interpreted recursively by another sign (which becomes its interpretant), a conception of meaning that does in fact imply a classification of sign types.

The psychology of perception suggests 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, gustatory, kinesthetic, etc. A list of sign types would include: writing, symbol, index, image, map, graph, diagram, etc. Some combinations of signs can be multi-modal, i.e. different types of signs grouped together for effect. But the distinction between a medium and a modality should be clarified:

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