---
name: "not"
module: "predicates"
section: "Logic"
params: [{ name: x, type: any }]
returns: bool
---
Logical negation. Returns `#t` when `x` is falsy (`#f` or `nil`) and `#f` otherwise.
```sema
(not #f) ; => #t
(not nil) ; => #t
(not 0) ; => #f
(not '()) ; => #f
```