Salience — Flat Dimension Typeclasses

@cite{ariel-2001} @cite{aissen-2003}

A unified interface to the salience dimensions used across linglib:

• Accessibility (@cite{ariel-2001}) — how mentally available a referent is, on the 18-level Accessibility Marking Scale.
• Animacy (@cite{aissen-2003}, @cite{just-2024}) — referent prominence by humanness.

These dimensions are not unified into a single Salience scale on purpose. Animacy and accessibility correlate but diverge (humans can be inaccessible newcomers; inanimates can be highly accessible topics). Bundling them would obscure the divergences that the literature carefully documents.

What this module provides instead is a flat collection of typeclass projections so that downstream theories can ask "what is X's animacy / accessibility?" without committing to a particular representation. The trivial identity instances on the underlying types make these classes a no-op when the data is already in the canonical form, and a hook for extension when a theory needs to project a richer object down onto one of the dimensions.

Per-axis typeclasses for the four Krifka IS notions (HasGivenness, HasFocus, HasTopic, HasAtIssue) would naturally sit alongside HasAccessibility and HasAnimacy; add them when a real abstraction-consumer emerges, per mathlib's small-typeclass convention.

class Core.Salience.HasAccessibility (α : Type) : Type

Things that have an accessibility level on @cite{ariel-2001}'s 18-level scale.

• accessibility : α → Features.AccessibilityLevel

class Core.Salience.HasAnimacy (α : Type) : Type

Things that have an animacy level on @cite{aissen-2003}'s 3-level scale.

• animacy : α → Features.Prominence.AnimacyLevel

@[implicit_reducible]

instance Core.Salience.instHasAccessibilityAccessibilityLevel : HasAccessibility Features.AccessibilityLevel

Equations

• Core.Salience.instHasAccessibilityAccessibilityLevel = { accessibility := id }

@[implicit_reducible]

instance Core.Salience.instHasAnimacyAnimacyLevel : HasAnimacy Features.Prominence.AnimacyLevel

Equations

• Core.Salience.instHasAnimacyAnimacyLevel = { animacy := id }