Symbols:Symbolic Logic

$$\vee$$

"Or". A binary operation on two propositions. $$P \vee Q$$ means "either $$P$$ is true or $$Q$$ is true, or both."

Its technical term is "vel".

$$\wedge$$

"And". A binary operation on two propositions. $$P \land Q$$ means "$$P$$ is true and $$Q$$ is also true."

See Vector Algebra and Group Theory for alternative definitions of this symbol.

$$\neg$$

"Not". $$\neg Q$$ means not $$Q$$, the logical opposite (negation) of $$Q$$. The effect of the unary operator $$\neg$$ is to reverse the truth value of the following statement.

Deprecated Symbols
$$\cdot$$

"And". A binary operation on two propositions. $$P \cdot Q$$ means "$$P$$ is true and $$Q$$ is true." In this usage, it is called "dot".

An alternative to $$P \land Q$$, which is what is usually used by logicians.

See Arithmetic and Algebra, Vector Algebra and Group Theory for alternative definitions of this symbol.

$$-$$

"Not": an alternative to $$\lnot$$, which is what is usually used.

See Arithmetic and Algebra and Set Operations and Relations for alternative definitions of this symbol.