MATERIAL FALLACIES

MATERIAL FALLACIES

MATERIAL FALLACIES
• Fallacies of Relevance – irrelevant premises (diversion)
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The appeal to populace (ad populum)
The appeal to pity (ad misericordiam)
The appeal to force (ad baculum)
The argument against person (ad hominem)
Irrelevant Conclusion

• Fallacies of Defective Induction – weak premises
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The argument from ignorance (ad ignorantiam)
The appeal to inappropriate authority (ad vericundiam)
False Cause
Hasty Generalization

MATERIAL FALLACIES
• Fallacies of Presumption – too much assumption in the premises • Accident
• Complex question
• Begging the question

• Straw – Man Fallacy

Fallacy of Relevance
• The appeal to populace (ad populum) – a diversion from real premises to mere popularity. This fallacy can further imply an appeal to popular emotion.
• Example
• Capital punishment cannot be wrong; 75% of the people support it.

Fallacy of Relevance
• The appeal to pity (ad misericordiam) – a diversion from real premises to pity
• Example
• If you fail me, my parents will be devastated. They sacrificed all their savings on my tuition.

Fallacy of Relevance
• The appeal to force (ad baculum) – a diversion from real premises to fear
• Example
• All those in favor of my proposal, say “I agree;” all those who oppose, say “I resign.”

Fallacy of Relevance
• The argument against person (ad hominem) – a diversion from real premises to an attack to the arguer. The following a re variations of ad hominem fallacies: • Poisoning the well: a direct attack on the trustworthiness of the person making a statement instead of addressing the statement.
• “Your preaching is worthless.” “Why?” “Because you do not practice what your preach.”

• Tu quoque (you too): consists of accusing your critic of the same thing your critic accuses you of, rather than addressing the criticism itself.
• St. Augustine led a wild life himself during his youth, so what right does he have to tell us we should be saints?

• The genetic fallacy: refuting an idea by showing some suspicious psychological origin of it.
• You only say that because you are a woman.

Fallacy of Relevance
• Irrelevant Conclusion (ignoratio elenchi) – a type of fallacy in which the premises support different conclusion than the one that is proposed.
• Example:
• It may be argued that socialized medicine is necessary because many poor people die due to lack of adequate basic medical care. The premise is true an certainly proves something in the area of social needs, but it does not prove that socialized medicine is necessary even useful to attain its end.

Fallacy of Defective Induction
• The argument from ignorance (ad ignorantiam) – arguing that an idea must be true because we do not know that it is not.
• Example
• He cannot prove he earned that money, so he must have stolen it. Fallacy of Defective Induction
• The appeal to inappropriate authority (ad vericundiam) – appeal to legitimate authority itself is not fallacious. For
“authority” does not mean “might” (baculum) but “right.”
• Example
• “The Conjuangco-Aquinos are not corrupt.” “How do you know that?”
“Boy Abunda says so.”
• “Mary was assumed into Heaven.” “How do you know that?” “The Church says so.”

Fallacy of Defective Induction
• False Cause (non causa pro causa) – a fallacy in which something that is not really a cause, is treated as a cause.
Common in this fallacy is its subcategory post hoc ergo propter hoc (after the thing, therefore, because of the thing).
• Example
• “After we threw God out of the schools, we put man on the moon.”
• As prayers has gone out of the schools, guns, knives, drugs and gangs have come in.
• The Rooster says: My first crowing in the morning brings up the sun.

Fallacy of Defective Induction
• Hasty Generalization – mere examples can never provide certainty, only probabilities. Thus, its being fallacious is measurable to some degree depending on the samples present.
• Example
• We went to three ball games this year and the home team lost each one. They are losers.

Fallacy of Presumption
• Accident – a fallacy in which a generalization is wrongly applied to a particular case.
• Example
• Jogging is good for the health. Therefore, a person with asthma could also improve his health through jogging.

Fallacy of Presumption
• Complex question – a fallacy in which a question is asked in a way that presupposes the truth of some proposition buried within the question. The question consists of asking a question without “begging” another question.
• Example
• Have you stopped beating your wife?
• Who made God?

Fallacy of Presumption
• Begging the question (petitio principii) – a fallacy in which the conclusion is stated or assumed within one of the premises. It is assuming what you set out to prove. Also known as a circular argument.
• Example
• “Why does opium make one sleepy?” “Because it possess sleep-inducing power.” Straw-Man Fallacy
• It consists in refuting an unfairly weak version of your opponent’s idea
(either his conclusion or his argument) instead of a more reasonable idea he actually holds. You first set up a “straw-man,” or scarecrow, then knock it down, since a straw man is easy to knock down (and you created it).