Docs / Morphology / Paradigm / Contiguity

Paradigm contiguity: the *ABA generalization

import Linglib.Morphology.Paradigm.Contiguity · namespace Morphology

The *ABA generalization says graded paradigms are contiguous (IsContiguous), no form recurring across a distinct intervening form, for degree (positive < comparative < superlative, after Bobaljik), case (after Caha), and path roles (after Pantcheva). Of the five syncretism patterns of three cells, named as Bobaljik names the degree patterns, contiguity excludes exactly ABA.

Main definitions

Main results

References

The three-cell patterns

The five syncretism patterns of a three-cell chain, as form-class indices, named as Bobaljik 2012 names the degree patterns over positive < comparative < superlative. A concrete paradigm has a pattern when its syncretism, the kernel Setoid.ker, is the pattern's. ABA is the pattern contiguity excludes; AAB is contiguous, and its exclusion for degree is a vocabulary-level matter (Morphology/Exponence/Containment/Contiguity.lean).

L70–81

A three-cell paradigm has the ABA pattern iff its outer cells agree and its middle cell differs.

theorem ker_eq_ker_aba_iffL83–99
{F : Type u_1} (p : Paradigm 3 F) :
Setoid.ker p = Setoid.ker Paradigm.aba ↔ p 0 = p 2 ∧ p 0 ≠ p 1

Built from

A three-cell paradigm has the AAB pattern iff its lower cells agree and its highest cell differs.

theorem ker_eq_ker_aab_iffL101–117
{F : Type u_1} (p : Paradigm 3 F) :
Setoid.ker p = Setoid.ker Paradigm.aab ↔ p 0 = p 1 ∧ p 1 ≠ p 2

Built from

Two three-cell paradigms have the same pattern iff the same pairs of cells agree.

theorem ker_eq_ker_iff_fin_threeL136–150
{F : Type u_1} {G : Type u_2} (p : Paradigm 3 F) (q : Paradigm 3 G) :
Setoid.ker p = Setoid.ker q ↔ (p 0 = p 1 ↔ q 0 = q 1) ∧ (p 1 = p 2 ↔ q 1 = q 2) ∧ (p 0 = p 2 ↔ q 0 = q 2)