Ostensive Communication — @cite{sperber-wilson-1986}

Ostensive communication involves two layers of intention:

1. Informative intention: to make manifest (or more manifest) to the audience a set of assumptions
2. Communicative intention: to make mutually manifest to communicator and audience the communicator's informative intention

The communicative intention is what distinguishes ostensive communication from mere information transmission. It creates a PRESUMPTION OF OPTIMAL RELEVANCE (Postface p. 270), which triggers the comprehension procedure.

The presumption of optimal relevance does not have independent formal content — it is REALIZED BY the comprehension procedure (see Comprehension.lean). As S&W put it (Postface p. 271): "What makes it possible to recognise the communicator's informative intention is [the comprehension] procedure." The formal machinery that implements this presumption is RTScenario.comprehensionSelects: the satisficing search over interpretations ordered by accessibility IS what it means for the hearer to treat the stimulus as optimally relevant.

structure Theories.Pragmatics.RelevanceTheory.InformativeIntention (A : Type u_1) : Type u_1

An informative intention: the set of assumptions the communicator wants to make manifest (or more manifest) to the audience.

S&W (p. 58): "Informative intention: to make manifest or more manifest to the audience a set of assumptions {I}."

• intended : List A

  Which assumptions the communicator intends to make manifest

structure Theories.Pragmatics.RelevanceTheory.OstensiveStimulus (W : Type u_1) (A : Type u_2) : Type (max u_1 u_2)

An ostensive stimulus: a stimulus that makes manifest the communicator's intention to make certain assumptions manifest.

Can be linguistic (an utterance), gestural (pointing), visual (showing), or any behavior that attracts attention and focuses it on the communicator's meaning.

S&W (p. 63): "Communicative intention: to make it mutually manifest to audience and communicator that the communicator has this informative intention."

The ostensive stimulus triggers the comprehension procedure by creating a presumption of optimal relevance. This presumption is not formalized as a separate Prop — it is operationalized by the RTScenario.comprehensionSelects predicate in Comprehension.lean.

• informativeIntention : InformativeIntention A

  The communicator's informative intention

• communicatorEnv : CogEnv W A

  The communicator's cognitive environment