# Submit a negative fact

## Intention

I want to tell the case that a person is not insured.

## Incorrect form and why it stays silent

Polarity is written before the atom. A field in the assertion body does not replace not:

```text title="Incorrect form"
assert insured(person) { polarity negative; }
```

A second error is to negate the whole conjunction: `not (registered(p) and insured(p))` is rejected.

## Correct form

```law
language "law.core" version "0.2";
package recipes.v.r02 version "0.1.0";
namespace "urn:recipe:v-negation:02";

entity Person;
relation registered(p: Person);
relation insured(p: Person);
relation notice(p: Person);
rule Notice strict {
    for p: Person;
    when registered(p) and not insured(p);
    then notice(p);
}
```

## Frozen execution scene

| Facts | Question | Answer |
|---|---|---|
| registered(a), assert not insured(a) | notice(a) | TRUE_ONLY |
| registered(a), insured(a) { polarity negative; } | notice(a) | NEITHER |
| registered(a), no insured | notice(a) | NEITHER |

```law
test "explicit negative fact triggers notice" {
    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 registered(entity_ref("urn:recipe:v-negation:02:a"));
        assert not insured(entity_ref("urn:recipe:v-negation:02:a"));
    }
    evaluate truth(notice(entity_ref("urn:recipe:v-negation:02:a")));
    expect truth_status == TRUE_ONLY;
    expect applied(Notice);
}
```

```law
test "polarity field is no negation" {
    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 registered(entity_ref("urn:recipe:v-negation:02:a"));
        assert insured(entity_ref("urn:recipe:v-negation:02:a")) { polarity negative; }
    }
    evaluate truth(notice(entity_ref("urn:recipe:v-negation:02:a")));
    expect truth_status == NEITHER;
    expect not applied(Notice);
}
```

## Counterfactual

The two scene files differ in how the negative fact is written; the second keeps the wrong answer. teaches separately pins the ban on not over a conjunction (E1305).

## Boundary

A negative fact must have its own ground; negating a compound formula is rejected.

## Pitfall

`polarity negative` does not give negative support; the fix is `assert not`.