# Logical negation

Logical negation is an operation on one logical value, typically the value of a proposition, that produces a value of true when its operand is false and a value of false when its operand is true.

The truth table of $\operatorname{NOT}~ p,$ also written $\lnot p,\!$ appears below:

 $p\!$ $\lnot p\!$ $\operatorname{F}$ $\operatorname{T}$ $\operatorname{T}$ $\operatorname{F}$

The negation of a proposition $p\!$ may be found notated in various ways in various contexts of application, often merely for typographical convenience. Among these variants are the following:

 $\text{Notation}\!$ $\text{Vocalization}\!$ $\bar{p}\!$ $p\!$ bar $\tilde{p}\!$ $p\!$ tilde $p'\!$ $p\!$ prime $p\!$ complement $!p\!$ bang $p\!$

## Syllabus

### Focal nodes

 Inquiry Live Logic Live

## Document history

Portions of the above article were adapted from the following sources under the GNU Free Documentation License, under other applicable licenses, or by permission of the copyright holders.