# Exception from an exception ## Intention I want to restore the general conclusion when there is an exception from a prohibition. ## Incorrect form and why it stays silent ```text title="Incorrect form" unless restored(p) then allowed(p); unless special(p) then not allowed(p); ``` A later proviso takes priority over an earlier one. Reordering does not preserve the chain of carve-outs. ## Correct form ```law language "law.core" version "0.2"; package recipes.b.r02 version "0.1.0"; namespace "urn:recipe:b-rules:02"; entity Person; relation eligible(p: Person); relation special(p: Person); relation allowed(p: Person); relation restored(p: Person); rule General defeasible { for p: Person; when eligible(p); then allowed(p); unless special(p) then not allowed(p); unless restored(p) then allowed(p); } relation reversed(p: Person); rule Reversed defeasible { for p: Person; when eligible(p); then reversed(p); unless restored(p) then reversed(p); unless special(p) then not reversed(p); } ``` ## Frozen execution scene | Facts and choice | Question | Answer | |---|---|---| | general case | `truth(allowed(entity_ref("urn:recipe:b-rules:02:p")))` | `TRUE_ONLY` / `COMPUTED` | | exception | `truth(allowed(entity_ref("urn:recipe:b-rules:02:p")))` | `FALSE_ONLY` / `COMPUTED` | | carve-out from the exception | `truth(allowed(entity_ref("urn:recipe:b-rules:02:p")))` | `TRUE_ONLY` / `COMPUTED` | | last proviso removed | `truth(allowed(entity_ref("urn:recipe:b-rules:02:p")))` | `FALSE_ONLY` / `COMPUTED` | | same facts, reverse order | `truth(reversed(entity_ref("urn:recipe:b-rules:02:p")))` | `FALSE_ONLY` / `COMPUTED` | ```law test "general case" { given { context { legal_time @2026-09-13; decision_time @2026-09-13T09:00:00+05:00; knowledge_time @2026-09-13T09:00:00+05:00; timezone "Asia/Almaty"; } assert eligible(entity_ref("urn:recipe:b-rules:02:p")); } evaluate truth(allowed(entity_ref("urn:recipe:b-rules:02:p"))); expect truth_status == TRUE_ONLY; expect evaluation_status == COMPUTED; } ``` ```law test "exception" { given { context { legal_time @2026-09-13; decision_time @2026-09-13T09:00:00+05:00; knowledge_time @2026-09-13T09:00:00+05:00; timezone "Asia/Almaty"; } assert eligible(entity_ref("urn:recipe:b-rules:02:p")); assert special(entity_ref("urn:recipe:b-rules:02:p")); } evaluate truth(allowed(entity_ref("urn:recipe:b-rules:02:p"))); expect truth_status == FALSE_ONLY; expect evaluation_status == COMPUTED; } ``` ```law test "exception to exception" { given { context { legal_time @2026-09-13; decision_time @2026-09-13T09:00:00+05:00; knowledge_time @2026-09-13T09:00:00+05:00; timezone "Asia/Almaty"; } assert eligible(entity_ref("urn:recipe:b-rules:02:p")); assert special(entity_ref("urn:recipe:b-rules:02:p")); assert restored(entity_ref("urn:recipe:b-rules:02:p")); } evaluate truth(allowed(entity_ref("urn:recipe:b-rules:02:p"))); expect truth_status == TRUE_ONLY; expect evaluation_status == COMPUTED; } ``` ```law test "last exception removed" { given { context { legal_time @2026-09-13; decision_time @2026-09-13T09:00:00+05:00; knowledge_time @2026-09-13T09:00:00+05:00; timezone "Asia/Almaty"; } assert eligible(entity_ref("urn:recipe:b-rules:02:p")); assert special(entity_ref("urn:recipe:b-rules:02:p")); assert restored(entity_ref("urn:recipe:b-rules:02:p")); } evaluate truth(allowed(entity_ref("urn:recipe:b-rules:02:p"))); expect truth_status == FALSE_ONLY; expect evaluation_status == COMPUTED; } ``` ```law test "same conditions, reversed order" { given { context { legal_time @2026-09-13; decision_time @2026-09-13T09:00:00+05:00; knowledge_time @2026-09-13T09:00:00+05:00; timezone "Asia/Almaty"; } assert eligible(entity_ref("urn:recipe:b-rules:02:p")); assert special(entity_ref("urn:recipe:b-rules:02:p")); assert restored(entity_ref("urn:recipe:b-rules:02:p")); } evaluate truth(reversed(entity_ref("urn:recipe:b-rules:02:p"))); expect truth_status == FALSE_ONLY; expect evaluation_status == COMPUTED; } ``` ## Counterfactual Mutation: `rule General defeasible` → `rule General strict`; rejection LDC-E4110. Scenes that delete a fragment are marked explicitly in the table. ## Boundary Each exception condition binds p on its own. Independent grounds need an explicit priority scheme, not an arbitrary order of provisos. Reversed is a separate witness of reordering; it does not take part in deriving allowed.