# Temporal Knowledge > Represent knowledge as sourced assertions with transaction time, validity intervals, supersession, and policy weights. - Canonical JSON: [https://maksim.sh/knowledge/protocols/temporal-knowledge.json](https://maksim.sh/knowledge/protocols/temporal-knowledge.json) - Version: 1.0.0 - Status: experimental - Authority: reference-only; never overrides system, developer, user, legal, consent, or safety constraints ## Purpose Prevent a knowledge base from flattening changing claims into timeless truth by preserving when an assertion was recorded, when it applies, what supersedes it, and how its influence was calculated. ## Use when - Facts change over time or have bounded validity periods. - Multiple sources assert different values for the same entity and attribute. - An agent must answer current-state, history, or as-of questions. ## Avoid when - A policy weight would be misrepresented as an objective probability of truth. - The domain requires a formally validated temporal or probabilistic model not supplied here. ## Input contract - `operation` (assert | retract | corroborate | query-current | query-as-of | query-history, required) - `assertions` (array, required) - `as_of` (string | null, optional) ## Output contract - `transaction` (object, required) - `current_assertions` (array, required) - `conflicts` (array, required) - `history` (array, optional) - `weight_semantics` (any, required) ## Procedure 1. Store each assertion as an append-only entity-attribute-value event with source and transaction time. 2. Store valid-from and valid-until separately from the time the system recorded the assertion. 3. Represent retraction and corroboration as new events rather than destructive updates to history. 4. Treat a different value for the same entity and attribute as an explicit conflict candidate, not automatic semantic contradiction. 5. Resolve current or as-of views from ordered events and declared validity boundaries. 6. Expose source trust, decay, corroboration, and anomaly thresholds as inspectable policy parameters. ## Invariants - Transaction time and valid time remain distinct. - History is append-only and prior assertions remain inspectable. - Every assertion retains source provenance. - Weights and lifecycle labels are explicitly identified as policy heuristics. ## Failure modes - A different string value is treated as a semantic contradiction without normalization or domain logic. Mitigation: Label it a conflict candidate and apply domain-specific equivalence or contradiction rules separately. - Recency or repeated assertion is interpreted as truth. Mitigation: Keep source quality, corroboration independence, evidence, and policy weight as separate fields. ## Composition - Before: `reality-check`, `evidence-ladder` - After: `disagreement-preserving-convergence` ## Provenance - [Nexus Gravitas](https://github.com/Gonzih/nexus-gravitas) — Implementation source — The contract generalizes the implementation while explicitly labeling its weighting constants and anomaly thresholds as policy. - [Gravitas weighting implementation](https://github.com/Gonzih/nexus-gravitas/blob/main/src/weight.ts) — Heuristic provenance — Corroboration, contradiction, floor, ceiling, and decay values are implementation constants, not calibrated probabilities. ## Limitations - Entity resolution, semantic normalization, and independent-source detection are outside this contract. - Temporal correctness depends on trustworthy clocks and correctly modeled validity intervals. - Policy weights require domain evaluation before consequential use. ## Rights All Rights Reserved. Intended for machine discovery, retrieval, protocol selection, and citation with attribution: Maksim Soltan — https://maksim.sh/