1     Definition 2     Functional Requirements 3     Syntax
4     Semantics 5    Conformance Testing 6     Performance Assessment

Definition

Proposition is the digital representation of the content of a belief or knowledge statement. It encodes the semantic components of “who/what, does/is/has what, under which conditions” in a machine-readable form.
Proposition may include the following:
  • Subject
    The entity or concept the belief refers to (e.g., “Alice”, “Car”, “Trust”).
  • SubjectType
    Classification of the subject: PhysicalObject, Entity, or Concept.
  • PredicateCategory
    High-level category of the relation between subject and object:
    State, Action, Property, Ownership, Capability.
  • PredicateClass
    Specific relation type within the category:
    is, has, can, located_in, performs.
  • Object
    The value or entity linked to the subject via the predicate (e.g., “blue”, “Room42”).
  • ObjectType
    Classification of the object: Value, Entity, or Concept.
  • Domain
    Contextual domain of the proposition:
    PhysicalWorld, SocialContext, Self, OtherEntity, Task.
  • TemporalContext
    Time reference for the proposition (e.g., now, past, future).
  • SpatialContext
    Spatial attitude or location reference (linked to SpatialAttitude.json).
  • Modality
    Modal qualifier expressing necessity or possibility:
    must, may, possible, necessary.

Functional Requirements

  1. Structured Representation
    • The system shall represent every belief or knowledge statement as a structured Proposition object following the schema.
    • Each proposition shall include Subject, PredicateCategory, PredicateClass, Object, and Domain as required fields.
  2. Ontology Alignment
    • The system shall enforce enumerations for PredicateCategory, PredicateClass, Domain, and Modality according to linked ontologies.
    • The system shall validate that these enumerations match the ontology references provided in $comment fields.
  3. Contextualisation
    • The system shall support optional TemporalContext and SpatialContext fields to situate propositions in time and space.
    • The system shall allow Modality to express necessity or possibility (e.g., must, may, possible, necessary).
  4. Validation
    • The system shall validate propositions against the schema:
      • Required fields: Subject, PredicateCategory, PredicateClass, Object, Domain.
      • Enumerated values must match allowed sets.
      • Temporal and spatial references must conform to referenced schemas (Time.json, SpatialAttitude.json).
  5. Interoperability
    • The system shall ensure propositions are serializable in JSON and compatible with external reasoning engines.
    • The system shall maintain links to ontology URIs for semantic interoperability.
  6. Extensibility
    • The system shall allow additional attributes (e.g., certainty, provenance) through higher-level schemas (e.g., Knowledge-ToM) without breaking Proposition’s core structure.
  7. Integration
    • The system shall enable propositions to be embedded in Knowledge objects as the Proposition property.
    • The system shall support referencing propositions in predictions, conflicts, and explanations.
  8. Performance
    • The system shall validate and parse propositions efficiently to support real-time reasoning in metaverse or AI-driven environments.

Syntax

https://schemas.mpai.community/MMC/V2.5/data/Proposition.json

Semantics

Label Description
Header Proposition Header.
Standard‑PRP The characters “MMC‑PRG-V” marking the Proposition data type family.
Version Major version – 1 or 2 digits.
Dot‑separator The character “.” separating version components.
Subversion Minor version – 1 or 2 digits.
PropositionID Unique identifier for the Proposition instance.
PropositionData Unified Proposition object integrating all fields below.
Subject The Entity, object, or concept the belief is about.
SubjectType Type of subject: PhysicalObject, Entity, Concept.
PredicateCategory Category of the predicate: State, Action, Property, Ownership, Capability.
PredicateClass Specific predicate: is, has, can, located_in, performs.
Object The object or value associated with the belief.
ObjectType Type of object: Value, Entity, Concept.
Domain Context domain: PhysicalWorld, SocialContext, Self, OtherEntity, Task.
TemporalContext Time-related qualifier for the belief (e.g., now, past, future).
SpatialContext Spatial attitude or location associated with the belief (linked to SpatialAttitude schema).
Modality Modal qualifier expressing necessity or possibility: must, may, possible, necessary.
Trace
– Origin Module or subsystem that registered the Proposition.
– Timestamp Time of this Proposition instance.
DescrMetadata Additional descriptive metadata for extensibility (annotations, overrides, etc.).

5     Conformance Testing

A Data instance Conforms with MPAI-MMC Proposition(MMC-PRP) if:

  1.  Its JSON Object validates against its JSON Schema.
  2. Any included  JSON Object validates against its JSON Schema.
  3. All Data in the JSON Object:
    1. Have the specified Data Types.
    2. Conform with the Qualifiers signaled in their JSON Schemas.

6     Performance Assessment