Editing Hierarchy (section)

===Linguistics===
Many grammatical theories, such as [[phrase-structure grammar]], involve hierarchy.

[[Direct–inverse language]]s such as [[Cree language|Cree]] and [[Mapudungun language|Mapudungun]] distinguish subject and object on [[verb]]s not by different subject and object markers, but via a hierarchy of persons.

In this system, the three (or four with [[Algonquian languages]]) persons occur in a hierarchy of [[salience (language)|salience]]. To distinguish which is subject and which object, ''inverse markers'' are used if the object outranks the subject.

On the other hand, languages include a variety of phenomena that are not hierarchical. For example, the relationship between a pronoun and a prior noun-phrase to which it refers commonly crosses grammatical boundaries in non-hierarchical ways.