*valence* | *documentation* Specifies the number of arguments that a relation can take. If a relation does *not* have a fixed number of arguments, it does *not* have a *valence* *and* it is an *instance* of VariableArityRelation. For example, *holds* is a VariableArityRelation | |

**has arg2 ***valence* *singleValued* | |

**has axiom** (=> (*instance* ?REL VariableArityRelation) (*not* (exists (?INT) (*valence* ?REL ?INT))))
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**has axiom** (=> (*instance* ?FUNCTION UnaryFunction) (*valence* ?FUNCTION 1))
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**has axiom** (=> (*subrelation* ?PRED1 ?PRED2) (exists (?NUMBER) (*and* (*valence* ?PRED1 ?NUMBER) (*valence* ?PRED2 ?NUMBER))))
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**has axiom** (=> (*instance* ?FUNCTION BinaryFunction) (*valence* ?FUNCTION 2))
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**has axiom** (=> (*instance* ?FUNCTION TernaryFunction) (*valence* ?FUNCTION 3))
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**has axiom** (=> (*instance* ?REL BinaryPredicate) (*valence* ?REL 2))
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**has axiom** (=> (*instance* ?REL QuaternaryPredicate) (*valence* ?REL 4))
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**has axiom** (=> (*instance* ?REL QuintaryPredicate) (*valence* ?REL 5))
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**has axiom** (=> (*instance* ?REL TernaryPredicate) (*valence* ?REL 3))
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**has domain1** Relation | |

**has domain2** PositiveInteger | |

**is an ***instance* of AsymmetricRelation | |

**is an ***instance* of BinaryPredicate | |

BinaryRelation | **is first ***domain* of *DomainFn* | |

**is first ***domain* of *equivalenceRelationOn* | |

**is first ***domain* of *inverse* | |

**is first ***domain* of *irreflexiveOn* | |

**is first ***domain* of *partialOrderingOn* | |

**is first ***domain* of *RangeFn* | |

**is first ***domain* of *reflexiveOn* | |

**is first ***domain* of *totalOrderingOn* | |

**is first ***domain* of *trichotomizingOn* | |

**is second ***domain* of *inverse* | |

Predicate | **is first ***domain* of *singleValued* | |

Class | **is third ***domain* of *domain* | |

**is third ***domain* of *domainSubclass* | |

Abstract | **is ***disjoint* from Physical | |