Truth value

In logic, a truth value, or truth-value, is a value indicating to what extent a statement is true.

Related Topics:
Logic - True

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In classical logic, the only possible truth values are true and false.

Related Topics:
Classical logic - True - False

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However, other values are possible in other logics:

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fuzzy logic and other forms of multi-valued logic use more truth values than simply true and false.

Related Topics:
Fuzzy logic - Multi-valued logic

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Algebraically, the set {true,false} forms a simple Boolean algebra.

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Other Boolean algebras may be used as sets of truth values in multi-valued logic, while intuitionistic logic generalises Boolean algebras to Heyting algebras.

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In topos theory, the subobject classifier of a topos takes the place of the set of truth values.

Related Topics:
Topos theory - Subobject classifier

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