Symbols:Symbolic Logic/Deprecated Symbols/Ampheck

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Logical NOR

$\curlywedge$

Logical NOR.

A binary operation on two propositions.


$P \curlywedge Q$ means neither $P$ nor $Q$.


The $\LaTeX$ code for \(P \curlywedge Q\) is P \curlywedge Q .


Also see

The usual ways of expressing neither $P$ nor $Q$ nowadays are:

$\neg \paren {P \lor Q}$
$\overline {P \lor Q}$
$P \downarrow Q$


Historical Note

The ampheck was invented by Charles Sanders Peirce to denote the Logical NOR.


Linguistic Note

The word ampheck comes from the Greek $\alpha \mu \phi \eta \kappa \eta \varsigma$ (amphekes) meaning double-edged.

The word originates with Charles Sanders Peirce, to whom the shape invoked the concept of a double-edged sword.