Criticism Reductio ad Absurdum Dilemmas Counterexamples Fallacies.

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Presentation transcript:

Criticism Reductio ad Absurdum Dilemmas Counterexamples Fallacies

Reductio ad Absurdum aka. Modus Tollens P → Q Not Q Therefore, Not P

Reductio ad Absurdum If Determinism is true, then no actions are morally right or wrong. Some actions are morally right or wrong. Therefore, Determinism is not true.

Countering a Reductio Bite the Bullet Refute the Conditional

Dilemma Two Reductios together: “Disjunctive Premise”: P -> (Q or R) “Conjunctive Premise”: (Q->S) & (R->T) Therefore, S or T S and T are both absurd. Therefore, not P.

Dilemma If God exists, then either God allows evil or God is unable to prevent evil. If God allows evil, then God is evil; and, if God is unable to prevent evil, then God is unworthy of worship. God cannot be evil and God cannot be unworthy of worship. Therefore, God does not exist.

Countering a Dilemma Going Between the Horns Grasping the Horn Show a false dichotomy Grasping the Horn Refute one of the conditionals Bite a Bullet Accept one of the ‘absurd’ consequences

Counterexamples