an occurrence is identified by trace position, not by historical time

agent-decided, reversible. The previous formulation made an edit's identity its historical index and left that index a free field, so two edits at one time issued the same occurrence and a claim that freshness followed from the type rested on an unstated premise.

The trace is a list. Position is identity and order at once, and freshness stops being a premise. A realization that wants to record when an act happened carries that as data; two acts at one moment still issue distinct occurrences.

What the theorems consume is unique birth, not unique issuance of a content — which is what lets the same policy be adopted twice, once illicitly and once cleanly.

Rejected alternative: a separate edit identity with historical time beside it, which buys the same freshness at the cost of a second index nothing else uses.

Record: projects/normativity/legitimacy/rounds/2026-08-25-legitimate-evolution/COUNTERMODELS.md §2.