A unary logical connective, denoted

\begin{equation*} \lnot P \end{equation*}

and read

“not \(P\)”,

that is true if and only if

\(P\) is false.

Note. \(\lnot \lnot P \equiv P\).

(Levin 2021, sec. 0.2; Poole and Mackworth 2017, sec. 5.1)

---

• Synonyms
• Truth table