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Logic Also called a truth-functional operator or truth-functional constant. These connectives are special signs for the various relations between sentences, propositions, or statements in a truth functional system. They can not be used in isolation. Truth-functional connectives include: ∼ (negation), ∧ (conjunction), ∨ (disjunction),⊃ or → (implication), and ≡ or ↔ (equivalence). The role of these connectives is to determine the truth-value (the truth or falsity) of a truth-functional statement by the truth or falsity of its constituent statements. In daily language ∼ is expressed by “not,” ∧ by “and,” ∨ by “either … or,” ⊃ or ← by “if … then,” and ≡ or ↔ by “if and only if.” However, the logical connectives and their ordinary language counterparts can differ in implicature or even in meaning.“Any sentential connective whose meaning can be captured in a truth-table is called a truth-functional connective and is said to express a truth-function.”Forbes, Modern Logic ... log in or subscribe to read full text