Concepts
Everything in Ultimate Memory rests on one distinction: what a source said is not the same thing as what is currently true. Sources go stale, contradict each other, and get corrected. A memory that conflates the two either serves outdated statements as facts or silently rewrites history. This page defines the small vocabulary the whole system — and every answer it returns — is built from.
The courtroom analogy carries most of it: claims are the transcript (immutable testimony — who said what, when), facts are the verdict (the current adjudicated position, revisable as evidence arrives), and evidence is the recorded link between the two.
The terminology ladder
| Term | What it is | Can it change? |
|---|---|---|
| claim | what one source said — the permanent record of a single assertion, traceable to the exact place in the document it came from | never (immutable) |
| relation | a fact linking two entities — (Alice, works_for, Acme) | its validity window closes when superseded |
| observation | a fact stating a value about one entity — "Acme headcount: 600" | same rules; lives beside relations |
| fact | the umbrella word for relation or observation — what the system currently holds true | revisable, with the full history kept |
| core belief | a distilled knowledge page: compiled prose built only from well-supported, uncontradicted facts, every statement citing its evidence | recompiled when its evidence changes |
A sentence like "the roster says Bob is CFO" travels the ladder: it enters as a claim ("this file said it"), is adjudicated into a relation (Bob works_for Acme, the fact the system holds), and may end up cited by a core belief page if it is well-supported. Three layers, three words, no synonyms.
The grains — how answers are labeled
Every answer the system returns is typed with the grain of what it contains, so a caller always knows what kind of thing it is holding:
fact— relations and observations: what the system currently holds true, filtered by validity. This is the default place for "is it true now?" questions.evidence— claims: what sources asserted, possibly stale, superseded, or contradictory. This answers "who said what, when" — and is never allowed to pose as a current fact.compiled— knowledge pages: pre-paid synthesis with a freshness timestamp, useful for orientation before verifying specifics on the fact layer.
The default reading motion for an agent is orient → verify → audit: skim compiled knowledge to get oriented, verify anything load-bearing against the fact layer, and drill into claims and raw sources when the stakes demand it.
Two clocks
Facts carry two independent time axes, and keeping them apart is what makes time-travel queries honest:
- World time (validity): when something was true in the world — Alice worked at Acme from 2021 to 2024.
- System time (belief): when the system learned or stopped believing it — we found out in March.
"Who worked at Acme in 2022?" and "what did we believe last March?" are different questions with different answers, and both are askable. (Media adds a third, unrelated timestamp — where in a recording something was said — which is deliberately named apart so the three are never confused.)
Contradictions are surfaced, never resolved silently
When sources disagree — two documents state different FY2023 revenues — the system keeps both positions, groups them as a live contradiction, and returns the group together. Ranking may order them; nothing hides one side. Resolution is an explicit, recorded act, never a side effect of retrieval.
Evidence counting — what "well-supported" means
A fact's support counts distinct source lineages — independent documents that currently attest to it. Re-processing a document, repeated statements within one document, or ten versions of the same edited file never inflate support. When a source is deleted or its current version withdraws a statement, the facts it alone supported are closed — recorded and reversible, never silently vanished.