Definition:Logical Not

The logical not or negation operator is a unary connective whose action is to reverse the truth value of the statement on which it operates.


 * $$\neg p$$ is defined as: "$$p$$ is not true", or "It is not the case that $$p$$ is true".

Thus the statement $$\neg p$$ is called the negation of $$p$$.

"$$\neg p$$" is voiced "not $$p$$".

Truth Table
The truth table of $$\neg p$$ is as follows:

Notational Variants
Different symbols that you may encounter that mean the same thing as $$\neg p$$ are: