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A logical proposition produced by joining two simple propositions by the word "or". An example is the proposition "John is intelligent or John is modest"; it is false if both parts are separately false, otherwise it is true. The disjunction is used in mathematics – in which the proposition is true if either or both components are true. The disjunction of two simple propositions, P or Q, is written P ^ Q, and read "P or Q". See also conjunction.

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   • LOGIC