Basic Inference Here is a Basic Inference table. It contains Common Valid Arguments and Formal Fallacies. Valid Arguments Formal Fallacies Affirming the Antecedent P Q P Therefore, Q Denying the Antecedent P Q P Therefore, Q Denying the Consequent P Q Q Therefore, P Affirming the Consequent P Q Q Therefore, P Pure Hypothetical Syllogism P Q Q R Therefore, P R (No Corresponding Fallacy) Disjunctive Syllogism P Q P Therefore, Q Disjunctive Fallacy P Q P Therefore, Q Constructive Dilemma P Q R S P R Therefore, Q S Constructive Fallacy P Q R S Q S Therefore, P R Destructive Dilemma P Q R S Q S Therefore, P R Destructive Fallacy P Q R S P R Therefore, Q S DeMorgan's Law (P Q) is equivalent to ( P Q) And (P Q) is equivalent to ( P Q) Implication (P Q) is equivalent to ( P Q) And also equivalent to (P Q)

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