Abstract::
The principle of contradiction, traditionally
considered in its three variants, has now been challenged in each of these
versions. The imaginary situation presented by Lukasiewicz, in which people
know that to every true sentence there corresponds its true negation, suggests
another interpretation for the principle as a pragmatic rule of linguistic
action.
That language should be interpreted as a means of action and not only
as a means of representation is a point frequently made in the 20th century
philosophy. Austin's theory of performatives and the theory of speech acts,
developed by Searle, provide a theoretical framework to describe the related
phenomena. The logic of speech acts presented by Searle and Vanderveken
preserves the principle of contradiction. Language in action functions
as a sign. The new version of the principle of contradiction could be "a
sign is only a sign inasmuch it is opposed to other signs". This proposition
follows from the theses of de Saussure (language is a system of oppositions)
and Wittgenstein (tautology and contradiction mean nothing).
Even though some language phenomena seem to be counterexamples to that,
it is important to notice the deeper meanings of language utterances, as
discussed by Grice. Every utterance in natural language -- unless the language
"goes on holiday" -- can be held to derive its meaning from other utterances
which are opposed to it and which do not accompany it.