| antecedent | See conditional claim.
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| chain argument | An argument consisting of three conditional claims, in which the antecedents of one premise and the conclusion are the same, the consequents of the other premise and the conclusion are the same, and the consequent of the first premise and the antecedent of the second premise are the same.
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| claim variable | A letter that stands for a claim.
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| conditional claim | A claim that state-of-affairs A cannot hold without state-of-affairs B holding as well--e.g., "If A then B." The A-part of the claim is called the antecedent; the B-part is called the consequent.
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| conditional proof | A deduction for a conditional claim "If P then Q" that proceeds by assuming that P is true and then proving that, on that assumption, Q must also be true.
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| conjunction | A compound claim made from two simpler claims. A conjunction is true if and only if both of the simpler claims that compose it are true.
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| consequent | See conditional claim.
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| deduction (proof) | A numbered sequence of truth-functional symbolizations, each member of which validly follows from earlier members by one of the truth-functional rules.
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| disjunction | A compound claim made up of two simpler claims. A disjunction is false only if both of the simpler claims that make it up are false.
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| modus ponens | An argument consisting of a conditional claim as one premise, a claim that affirms the antecedent of the conditional as a second premise, and a claim that affirms the consequent of the conditional as the conclusion.
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| negation | The contradictory of a particular claim.
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| truth-functional equivalence | Two claims are truth-functionally equivalent if and only if they have exactly the same truth table.
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| truth-functional logic | A system of logic that specifies the logical relationships among truth-functional claims--claims whose truth values depend solely upon the truth values of their simplest component parts. In particular, truth-functional logic deals with the logical functions of the terms "not," "and," "or," "if . . . then," and so on.
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| truth table | A table that lists all possible combinations of truth values for the claim variables in a symbolized claim or argument and then specifies the truth value of the claim or claims for each of those possible combinations.
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