# `syntax.nested-negation`
## What it flags
Sentences that stack multiple negations. Two or more negations in the same sentence force the reader to mentally toggle truth values — a known burden for readers with aphasia and attention-fragile readers (ADHD), and a load multiplier for everyone reading under cognitive pressure. Plain-language guidelines (FALC, CDC Clear Communication Index, plainlanguage.gov) recommend rewriting double negatives as positives.
## At a glance
| | |
|---|---|
| **Category** | `syntax` |
| **Default severity** | `warning` |
| **Default weight** | `2` |
| **Condition tags** | `aphasia`, `adhd`, `general` |
| **Languages** | EN · FR (language-specific counting) |
| **Source** | [`src/rules/nested_negation.rs`](https://github.com/bastien-gallay/lucid-lint/blob/main/src/rules/nested_negation.rs) |
## Detection
Count the negations per sentence; report sentences whose count exceeds `max_negations`.
- **English** — sum of word-boundary matches against the language's negation list (`not`, `no`, `never`, `none`, `nothing`, `nobody`, `nowhere`, `neither`, `nor`, `cannot`, `without`) plus occurrences of the contracted `n't` suffix (`don't`, `won't`, `isn't`, `doesn't`, …).
- **French** — pair-based bipartite counting. Each `ne` / `n'` clitic contributes one negation and pairs with its nearest second-position particle (`pas`, `rien`, `jamais`, `plus`, `personne`, `aucun`, `aucune`, `guère`, `nulle part`) within a short window; the pairing just consumes the particle to avoid double-counting. Unpaired particles in a `ne`-sentence contribute one more — this catches forms like `rien` used as a nominal negative subject. Guards: `pas` / `plus` never count when unpaired (too ambiguous outside `ne …`); `rien` preceded by `de` is treated as the idiom `de rien` and skipped; particles in a sentence with no `ne` clitic are skipped too (`plus de courage`, `personne d'autre`). Standalones `sans` / `non` always count.
## Parameters
| Key | Type | `dev-doc` | `public` | `falc` |
|---|---|---|---|---|
| `max_negations` | `int` | 3 | 2 | 1 |
## Examples
`lucid-lint` reports; the rewrite is always yours.
### English
Three negations → three affirmatives, colour-matched across the rewrite. The `not` simply drops — the simplification shows.
**Before** (flagged):
> We do <span class="lucid-idea" data-idea="1">not say</span> <span class="lucid-idea" data-idea="2">nothing</span> is <span class="lucid-idea" data-idea="3">never possible</span>.
Three negations (`not`, `nothing`, `never`).
What `lucid-lint check --profile public` reports:
```text
warning input.md:1:1 Sentence stacks 3 negations (maximum 2). Rewrite as a positive statement or split the negations across separate sentences. [syntax.nested-negation]
```
**After** (your rewrite):
> We <span class="lucid-idea" data-idea="1">say</span> <span class="lucid-idea" data-idea="2">something</span> <span class="lucid-idea" data-idea="3">is possible</span>.
### French
**Passes under `public`:**
> Nous ne sommes pas prêts.
Bipartite `ne ... pas` counts as one negation.
**Before** (flagged):
> Nous <span class="lucid-idea" data-idea="1">ne disons pas</span> que <span class="lucid-idea" data-idea="2">rien</span> <span class="lucid-idea" data-idea="3">n'est jamais possible</span>.
Three negations: `ne…pas` (one bipartite), `rien` (unpaired), `n'…jamais` (one bipartite).
What `lucid-lint check --profile public` reports:
```text
warning input.md:1:1 Sentence stacks 3 negations (maximum 2). Rewrite as a positive statement or split the negations across separate sentences. [syntax.nested-negation]
```
**After** (your rewrite):
> Nous <span class="lucid-idea" data-idea="1">disons</span> que <span class="lucid-idea" data-idea="2">quelque chose</span> <span class="lucid-idea" data-idea="3">est possible</span>.
## Suppression
See [Suppressing diagnostics](../guide/suppression.md).
## See also
- [`syntax.passive-voice`](./passive-voice.md)
- [`structure.deep-subordination`](./deep-subordination.md)
- [Conditions](../guide/conditions.md)
## References
- [Clark & Chase (1972)](../references.md#clark-chase-1972)
- [Carpenter & Just (1975)](../references.md#carpenter-just-1975)
- [Kaup et al. (2006)](../references.md#kaup-2006)
See [References](../references.md) for the full bibliography.