# not: reversing a true-or-false answer

[Syntax and values](README.md)

## Behavior and details

`not` reverses one Boolean answer: true becomes false, and false becomes true. Reversing a yes-or-no answer is called **negation**.

`not` groups before comparisons. Write `not (a == b)` when you want to reverse the result of the whole comparison. Pliro does not guess that zero, empty text, or an empty list should mean false. Only an actual Boolean can be used here.

## Example

```pliro
# language: en
let ready = true
say not ready
say not (2 == 3)
```

## Related entries

[Syntax and values](README.md) · [Built-ins](../builtins/README.md) · [Programming guides](../guides/README.md)