# Relationship **Meta-Universe Specification** **Document ID:** MU-V2-CORE-006 **Title:** Relationship — A First-Class Semantic Entity **Document Class:** Normative **Version:** 2.0 (Draft) **Status:** Working Draft **Normative References:** MUC, MUFP **Informative References:** [Object](../04-core-concepts/Object.md), [Event](../04-core-concepts/Event.md) **Copyright:** © Orkestron.AI **License:** Apache-2.0 --- # 1. Purpose This document defines the concept of a **Relationship** within the Meta-Universe. A Relationship is a first-class semantic entity that expresses a meaningful connection between two or more Meta-Objects. Relationships are governed, versioned and traceable independently from the objects they connect. --- # 2. Definition A Relationship represents a semantic assertion describing how Meta-Objects are connected. A Relationship is a **first-class semantic entity, not a technical link.** In real organizations, relationships frequently carry more meaning than the objects they join: the bond *employee ↔ manager*, the bond *person ↔ family*, the bond *company ↔ contract* — these are where obligation, authority and consequence actually live. The Meta-Universe therefore governs Relationships in their own right, with their own identity, lifecycle, ownership and provenance. A Relationship SHALL describe meaning rather than implementation. Implementation-specific references, foreign keys or graph edges SHALL NOT be considered semantic relationships unless they explicitly represent semantic meaning. --- # 3. Relationship Principles Every Relationship SHALL: - have a well-defined semantic meaning; - reference one or more Meta-Objects; - preserve traceability; - have an identifiable lifecycle; - belong to an authoritative Universe; - remain independent from storage technology. Relationships are semantic objects in their own right. --- # 4. Core Components Every Relationship SHOULD define: - canonical identifier; - relationship type; - source object(s); - target object(s); - semantic meaning; - cardinality; - lifecycle state; - owner; - provenance; - version. Additional metadata MAY be defined by domain Meta-Models. --- # 5. Relationship Types Typical relationship categories include: - Association - Composition - Aggregation - Dependency - Ownership - Membership - Assignment - Reference - Derivation - Equivalence Domain Meta-Models MAY introduce additional relationship types. --- # 5a. Relationship Profile A **Relationship Profile** is a standardized, reusable class of relation that MAY be shared across meta-models so that the same connection means the same thing everywhere it appears. Recommended baseline Relationship Profiles include: - `reportsTo` — an actor is accountable to another within an authority structure; - `owns` — an actor holds ownership of an object; - `memberOf` — an object participates in a group or collective; - `dependsOn` — an object requires another to function or to hold meaning; - `implements` — an object realizes a specification, capability or contract. A Relationship Profile SHOULD define its semantic meaning, expected source and target categories, default cardinality and typical temporal behavior. Meta-Models SHOULD reuse published Relationship Profiles rather than redefining equivalent relations, so that connections remain comparable and federatable across Universes. Local extensions to a Relationship Profile SHALL remain additive and SHALL NOT redefine its established meaning. --- # 6. Cardinality Relationship cardinality SHALL be explicit whenever applicable. Typical forms include: - One-to-One - One-to-Many - Many-to-One - Many-to-Many Cardinality SHALL describe semantics rather than database implementation. --- # 7. Identity Every significant Relationship SHALL possess a canonical Identity. Identity SHALL remain stable throughout the lifecycle of the Relationship. Changing relationship attributes SHALL NOT create a new identity. Replacing the semantic meaning SHALL create a new Relationship. --- # 8. Ownership Every Relationship SHALL have an authoritative owner. Ownership determines responsibility for establishing, maintaining and retiring the relationship. Ownership SHALL remain traceable. --- # 9. Lifecycle A Relationship SHOULD progress through explicit lifecycle states such as: - Proposed - Active - Suspended - Deprecated - Retired Lifecycle transitions SHALL be represented through Events. --- # 10. Temporal Validity A Relationship MAY include temporal validity. Typical attributes include: - validFrom; - validUntil; - observedAt; - terminatedAt. The temporal validity and lifecycle of a Relationship SHALL be expressed through the [Event](../04-core-concepts/Event.md) primitive and recorded on the Semantic Timeline, so that *when* a connection held — and when it ceased to hold — is reconstructable independently of the current state of the objects it joins. Temporal validity SHALL NOT affect canonical identity. --- # 11. Events Creation, modification and retirement of Relationships SHOULD be represented by immutable Events. Historical states SHALL remain reconstructable. --- # 12. Federation Relationships MAY span Objects originating from different Universes. Cross-Universe Relationships SHALL: - preserve the canonical identities of all participating Objects; - identify the authoritative owner; - reference the governing federation agreement when applicable. Federation SHALL NOT transfer ownership of participating Objects. --- # 13. Imported Relationships Imported Relationships SHALL preserve: - originating namespace; - provenance; - version; - semantic meaning. Local extensions SHALL remain additive. --- # 14. Traceability Every Relationship SHALL preserve: - provenance; - ownership history; - lifecycle history; - event history; - semantic lineage. Relationship history SHALL remain auditable. --- # 15. Validation A conforming implementation SHOULD validate: - referenced object identities; - relationship type; - cardinality; - semantic consistency; - lifecycle state; - federation constraints. --- # 16. Architectural Invariants Every Relationship SHALL preserve: - semantic meaning; - canonical identity; - traceability; - ownership; - constitutional compliance. Relationships SHALL NEVER be reduced to implementation-only links. --- # Future Directions The Meta-Universe advances a guiding principle: **meaning emerges from Relationships, not only from Objects.** As this principle matures, a future **Relationship Profile catalog** is anticipated — a published, federatable library of standardized relation classes (extending the `reportsTo` / `owns` / `memberOf` / `dependsOn` / `implements` baseline) that meta-models can import the way they import Namespaces, so that the *structure* of knowledge becomes as reusable and as discoverable as the entities within it. This direction is anticipated but not yet normative. --- # Final Statement A Relationship is a first-class semantic construct of the Meta-Universe. It represents meaningful connections between Meta-Objects, enabling knowledge to be modeled as an evolving semantic network whose structure is as important as the objects themselves. By treating Relationships as independently governed artifacts, Meta-Universe preserves meaning, traceability and interoperability across federated semantic universes.