## Foundations of Mathematics## Mathematical and Formal Logic |

## What are logical operators in predicate calculus? |

Predicate calculus commonly uses seven special symbols—called *logical operators—* to express a formula (in this case, a formula is a meaningful expression built up from atomic formulas by repeated application of the logical operators). The following table lists the symbols and their meanings. (Note: Many of these symbols are also used as logical operators in truth tables; see below.)