Every term is about something in the world

Answers Metaphysics · Ontology

Every row grounds on exactly one Entities row: the thing in the world the row is ultimately about. Grounding is a relationship like any other and is declared like one - a verb, a named inverse, a governed cardinality and a constitutive claim - so it can be read from either end. It is declared once for the whole model rather than repeated by each kind, because it is a relationship every kind makes and no kind owns, and it is asserted once, on the row, never a second time as a separate assertion saying the same thing.

What goes wrong without it

A term that does not say what it is about cannot be joined to anything: two terms describing the same thing in the world are unrecognisable as such, and a vocabulary of terms floats free of the subject matter it was built to describe. Declaring it as a bare field rather than a relationship costs more than tidiness. A field reads in one direction only, so the thing being described never learns what describes it - the entity a hundred terms are about renders as though nothing points at it, which is the opposite of the truth and the single most misleading thing a knowledge graph can tell a reader. Stated as a relationship with a named inverse, both readings come back for free, and the grain declaration every term already makes becomes traversable rather than merely recorded.

What proves it — 1

Each is a gate the build runs: a check inside a ring, a whole ring, or an eval beside them. A build stops at the first that refuses.

• registry integritytyped relationships
  Every relationship has declared endpoint kinds and a governed cardinality.

Derived from — 2

• Kimball GroupDeclaring the Grain
• W3COWL 2 Web Ontology Language Primer

Kinds it licenses

Relationships it licenses

grounds on

Where this model stands

Every row outside Entities grounds on exactly one Entities row, so no row is stated without the subject it is about.

An Entities row grounds on itself, which is not an assertion: the subject of a subject is itself, so grounding is expanded for every kind but Entities.

The grounding a row states is read from both ends - the row names what it is about, and the entity names everything that is about it - from one stored fact rather than two.

What it does not claim

Grounding is stated against one Entities row per row. A row that is genuinely about two things is not yet expressible, and would need a second Entities relationship rather than a second value in this one.

RUL-022