Commutation test

In semiotics, the commutation test is used to identify the value or signficance of any of the signifiers used in the material to be analysed.

Discussion

The first stage of development in semiotics related to the spoken and/or written form of language. Later, it was expanded to cover all sign systems that have an informational content. As Umberto Eco says, "A sign is everything which can be taken as significantly substituting for something else." (1976)

Semiotics studies the relationship between the form of the sign (the signifier) and the meaning expressed (the signfied), and thereby attempts to reveal the process of communicating understanding. Hence, language begins with a sign (sometimes called a signal). Of the many possible meanings that it can be used to convey, one or more will be selected and encoded, i.e. the chosen meaning(s) will be denoted or associated with the sign within the broader framework of syntactic and semantic systems available within the community. When the audience is exposed to the sign, the expectation is that they will be able to decode the meaning. In lexicography, the fact that a neologism is used marks its acceptance into the language. This will not be a difficult process so long as each sign has a limited and immediately useful meaning. The problem arises when several possible meanings or shades of meaning become associated with the sign. This is a shift from denotational to connotational meanings. Rules of interpretation are required to resolve uncertainty. Within the community, such rules are, for the most part, experiential and applied unconsciously. Members of a community have a shared memory of language patterns and norms which, for the most part, are stable over long periods of time. Individuals are therefore able to build up a cognitive framework which identifies the possible meanings from any grouping of signs and selects one considered the most appropiate from the context. This intuitive system is continuously tested through the audience's responses. If the responses are satisfying, intuition prevails. If the responses are obviously inappropriate, the audience will consciously review the thought process and decide whether to modify the framework. Semiotics has developed a more precise methodology for this interpretive process.

The commutation test

This test is used to identify distinctive signifiers and to define their significance. It works through a process of substitution, testing whether a change in the signifier leads to a change on the level of the signified. The first step, therefore, is to exclude one signifier from the material to be analysed. This is a test of redundancy: to identify what meaning is lost (if any) by omitting it. It will be relatively unusual to find that one sign is completely superfluous, but more common to find that the contribution of the one sign to the whole meaning is relatively weak. The weakness or strength of its contribution can be calibrated more exactly by placing alternate (synonymous) signs in the context. This will enable the analyst to make a judgement on the distinctiveness of the particular signifier chosen by the author/artist and of its value to the meaning, i.e. as more or less necessary for maintaining the meaning and/or rule structure in different occurrences. By also placing the original sign into different contexts, it can be seen whether the sign becomes more or less distinctive.

References

Eco, Umberto. "A Theory of Semiotics" (1976) (Original English version of Trattato di semiotica generale, 1975)