# Treat a document as received

## Intent

I want to derive legal receipt from an established method of delivery.

## Wrong form and why it stays silent

```law title="Incorrect form"
relation received(d: Letter) kind empirical;
fiction Receipt strict { for d: Letter; when delivered(d); deem received(d); }
```

A fiction establishes legal receipt, not observation of actual reading. An empirical head raises warning E1309.

## Correct form

```law
language "law.core" version "0.2";
package recipes.g.r04 version "0.1.0";
namespace "urn:recipe:g-concepts:04";

entity Letter;
relation delivered(d: Letter);
relation received(d: Letter) kind institutional;
fiction Receipt strict { for d: Letter; when delivered(d); deem received(d); }
```

## Frozen execution scene

| Facts on 13.09.2026 | Question | Answer |
|---|---|---|
| delivery established | `truth(received(entity_ref("urn:recipe:g-concepts:04:p")))` | `truth_status == TRUE_ONLY;` / `COMPUTED` |
| no delivery | `truth(received(entity_ref("urn:recipe:g-concepts:04:p")))` | `truth_status == NEITHER;` / `COMPUTED` |
| fiction removed | `truth(received(entity_ref("urn:recipe:g-concepts:04:p")))` | `truth_status == NEITHER;` / `COMPUTED` |

```law
test "established delivery deems receipt" {
    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 delivered(entity_ref("urn:recipe:g-concepts:04:p"));
    }
    evaluate truth(received(entity_ref("urn:recipe:g-concepts:04:p")));
    expect truth_status == TRUE_ONLY;
    expect evaluation_status == COMPUTED;
}
```

```law
test "no delivery stays unknown" {
    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";
        }

    }
    evaluate truth(received(entity_ref("urn:recipe:g-concepts:04:p")));
    expect truth_status == NEITHER;
    expect evaluation_status == COMPUTED;
}
```

```law
test "removed fiction stays unknown" {
    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 delivered(entity_ref("urn:recipe:g-concepts:04:p"));
    }
    evaluate truth(received(entity_ref("urn:recipe:g-concepts:04:p")));
    expect truth_status == NEITHER;
    expect evaluation_status == COMPUTED;
}
```

## Counterfactual

Mutation `relation received(d: Letter) kind institutional;` → `relation received(d: Letter) kind empirical;`: LDC-E1309 (warning, exit code 0).

## Boundary

Delivery is a case fact. Validity conditions of service and the temporal point are set by the act separately; a single fiction does not certify that the addressee read the document.