MATERIAL FALLACIES

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MATERIAL FALLACIES

• Michael Jhon M. Tamayao, M.Phil.
• College of Medical Technology

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Topic Outline

• Introduction What are Material Fallacies?
• Types of Material Fallacies
• Fallacies of Language
• Equivocation
• Amphiboly
• Composition
• Division
• Accent
• Figures of Speech

• Fallacies not of Language
• Accident
• Irrelevant Conclusion
• Appeal to Authority
• Appeal to Fear
• Appeal to the Majority
• Appeal to the Person
• Appeal to Pity
• Affirming the Consequent
• Denying the Antecedent
• Begging the Question
• False Cause
• Complex Question
• Summary
• Exercises

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OBJECTIVES

• At the end of the discussion, the student must be
  able to
• Distinguish a good argument from a fallacious
  argument.
• Debunk a fallacious argument.
• Use a fallacy in practical situations.

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INTRODUCTION

• What is a Fallacy?
• The word fallacy came from the Latin word
  fallo, which means I deceive.
• Either formal or informal (material)
• In his Organon (De Sophistici Elenchi), Aristotle
  studied the different informal fallacies in the
  rhetorical arguments of the Sophists

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INTRODUCTION

• Why should we study fallacies in Logic?
• Good arguments are best known and appreciated by
  contrasting them from bad arguments.
• Readiness in recognizing fallacies will put you
  on guard against deceptions.
• Familiarity with the fallacies will give you a
  great advantage over an opponent in discussion
  and debate

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FALLACIES OF LANGUAGE

• EQUIVOCATION
• AMPHIBOLY
• COMPOSITION
• DIVISION
• ACCENT
• FIGURES OF SPEECH

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FALLACY OF EQUIVOCATION

• It is the fallacy of using a word in two senses
  in an argument.
• Aside from being an equivocal term, the ambiguous
  word could also be an analogous term.
• It is a deceptive argument which lets the
  listener believe that two different terms
  (represented by one word or sound) are actually
  the same.

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FALLACY OF EQUIVOCATION

• EX.
• Microscope is the official logo of CMT. I just
  used a microscope in the science lab awhile ago.
  Thus, we can also use the official logo of CMT in
  looking at the structure of minute objects and
  organisms.
• God is a Perfect Being.
• Michelangelo is a god.
• Therefore, Michelangelo is a Perfect Being.

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AMPHIBOLY

• It is a deception resulting from the grammatical
  or syntactical ambiguity of language.
• Although it uses univocal terms, an amphiboly can
  be interpreted in various ways.
• EX. 1
• The Oracle gave to King Croesus this message
  when he was planning a war against Persia
• If Croesus wages war against the Persians,
• He will destroy a mighty kingdom.
• Whose kingdom?
• EX. 2
• Go slow men at work

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COMPOSITION

• The fallacy of composition consists in taking
  words or phrases as a unit when they should be
  taken separately.
• EX.
• Cajus I admit that thieves and murderers cannot
  enter the kingdom of heaven Yes, I am a thief,
  but not a murderer. So I can still enter the
  kingdom of heaven.

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COMPOSITION

• From Each to All
• Arguing from some property of constituent parts,
  to the conclusion that the whole (composite) item
  has that property.
• Examples
• The components parts of the car is relatively
  heavy. Therefore, the car is only relatively
  heavy.
• All the members of the basketball team is highly
  skilled. Therefore the entire basketball team is
  highly skilled.

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DIVISION

• Converse of the fallacy of composition
• Consists in taking separately what should be
  taken together as a unit.
• Arguing from a property of the whole, to each
  constituent part.
• Example
• Rats are all over the world.
• My pet, Sparky, is a rat.
• Therefore, Sparky is all over the world.

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DIVISION

• Examples
• All in this room weighs about a ton
• But Zambo is in this room
• Therefore Zambo weighs about a ton.
• Philippines (the whole) is a poor country
• Gloria (part) is a Filipino.
• Therefore Gloria is poor.

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ACCENT

• Very similar to amphiboly only that it creates
  ambiguity not through its grammatical structure
  but through its changing emphasis.
• The oral counterpart of amphiboly.
• Consists of emphasizing the wrong word in a
  sentence.
• It is an ambiguity that results from shifting
  emphasis from one word to another.

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ACCENT

• Examples
• The Med Tech Basketball Team is not a SORE loser.
• The Med Tech Basketball Team is not a sore LOSER.
• The Med Tech Basketball Team is not a sore loser.

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ACCENT

• Examples
• THE PHILIPPINES WON 10 GOLD MEDALS IN THE
  OLYMPICS according to Madam Aurings
  foresight
• TWO CSUans CAUGHT SLEEPING TOGETHER AT BACK OF
  THE AMPHITHEATER
  because their father kicked them
  out from their house.

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ACCENT

• Example

SALE! 50 OFF on selected items
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FALSE ANALOGY

• The confusion between the metaphorical and
  ordinary uses of a word or phrase.
• Consists in wrongly inferring similarity of
  meaning from similarity of word structure.
• Example
• What is immaterial is not material
• And what is insoluble is not soluble
• Therefore what is inflammable is not flammable.

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FALLACIES NOT OF LANGUAGE

• Accident
• Irrelevant Conclusion
• Appeal to Authority
• Appeal to Fear
• Appeal to the Majority
• Appeal to the Person
• Affirming the Consequent
• Denying the Antecedent
• Begging the Question
• False Cause
• Complex Question Fallacy of Accident

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ACCIDENT

• The fallacy of accident consists in confusing
  what is essential or necessary to a thing and
  what is merely accidental to it.
• Example
• Dialogue between teacher and student
• Teacher Did you read your lesson?
• Student Of course sir.
• Do you know how many periods are there in the
  article?
• No sir
• So youre saying that you know at the same time
  you dont know.

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ACCIDENT

• Concentrating on one accidental aspect of a thing
  which may or may not actually happen.
• Example
• Alcoholic drinks lead to drunkenness and should
  therefore be forbidden.
• Good food leads to overeating and should
  therefore be forbidden.
• Illegal Drugs leads to addiction and should
  therefore be forbidden.

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ACCIDENT

• Being too strict about the qualities of things to
  the point of not considering exemptions.
• Example
• Cutting people is a crime. Surgeons cut people.
  Therefore, surgeons are criminals.

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IRRELEVANT CONCLUSION

• Ignoratio Elenchi
• Consists in proving a conclusion other than the
  one that should be proved.
• It is simply missing the point of the dispute
• Diverts attention away from a fact in dispute
  rather than address it directly.

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IRRELEVANT CONCLUSION

• Examples
• There have been bad popes
  therefore the pope is not infallible.
• He wasnt guilty. He was nice to all the kids and
  very athletic. We played basketball and
  water-skied with him and had wonderful times.
  Hed do anything for anybody.
• She is really a very kind lady.

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a. Appeal to Authority

• Argumentum ad Verecundiam
• Associating an argument or conclusion with the
  fame, reputation, or prestige of some person or
  institution.
• social status proof
• You should believe my truth because I have more
  famous people supporting it than my opponents
  have famous people supporting their truth.
• The argument is intended to take advantage of an
  audiences ignorance by exploiting its respect
  for authority.

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a. Appeal to Authority

• Example
• Debate over marijuana - Some authorities believe
  it causes permanent reduction in intelligence and
  general brain function while other authorities
  believe it is no worse than tobacco and maybe
  better.
• Always prefer the merits (proofs) for an argument
  to the fame of its supporters, and always feel
  free to sift information for yourself.

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a. Appeal to Authority

• Examples
• Ramon Revilla must be a pretty good senator.
  After all, he had the support of President
  Estrada.
• Pornography must be harmless because a Federal
  Task Force said it is.
• As a Ph.D. and president of the Philippine
  Literary Society, I think this is a good novel.
• Vicky Bello recommends this Bello facial product.
  

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a. Appeal to Authority

• Examples
• This must be a good beer because Manny Pacquiao
  endorses it.
• If you want the opinion of an expert, ask my
  neighbor, Dr. Phosphate. He has a Ph.D. in
  Chemistry. He will tell you that Leonardo Da
  Vinci is a better painter than Michelangelo.
• These opinions about world peace must be
  excellent and profound because they belong to
  that brilliant, world-famous theoretician Albert
  Einstein.

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b. Appeal to Force

• Argumentum ad Baculum
• This is simply the adult form of arguing the way
  a bully does if you don't accept my opinion,
  I'll punch you in the nose.
• he arguer demands acceptance of his proposition
  not because it is true or proved but because
  there are consequences for rejecting it.

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b. Appeal to Force

• Examples
• If you expect to receive allowance tomorrow, I
  suggest you dont talk to your boyfriend anymore.
  
• Vote in the morning die in the afternoon. --El
  Salvador guerrilla slogan, 1982
• Youd better have an abortion, or I'll tell
  everybody you're a whore and then leave you for
  good.

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b. Appeal to Force

• Examples
• You dont like our plans for the new Model 21?
  Well, if you don't like the products our company
  is planning to bring out, maybe you should be
  working for someone else. If you can't overcome
  your negative feelings, let me know and I'll
  write you a letter of recommendation.
• I shoot people who don't agree with me. Don't you
  think that's a good idea?

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c. Appeal to Personal Ridicule

• Argumentum ad Hominem
• One of the most common fallacies of irrelevant
  evidence.
• Relies upon character assassination as a
  substitute for refutation of an opponents
  thesis.

Blah blah
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c. Appeal to Personal Ridicule

• Examples
• Jun Lozada is not credible because he looks funny
  when he cries.
• President Gloria and her colleagues have often
  been attacked by former President Estrada, a hero
  of the masses, who was once incarcerated because
  of plunder.
• How can Jesus be the Messiah? He is just the son
  of Joseph the carpenter.
• Well naturally he opposes my position. What can
  you expect from a third-grade dropout who drinks
  like a fish, sells drugs to kids, and tortures
  animals?

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c. Appeal to Personal Ridicule

• Apophasis--pretending to deny what is really
  being asserted
• Although it is obvious from his response, I pass
  silently over the fact that my opponent has only
  a high school diploma--and from a rather weak
  school district at that.
• I wish to announce that race will not be an issue
  in this campaign. Just because my opponent is
  black, I will not encourage the so-called
  anti-black vote by stressing what a black might
  do if he were elected.
• Of course, I don't mean to suggest that you have
  a rather limited ability to grasp the worth of my
  project or that you do not have the vision and
  experience necessary to understand it I simply
  would like you to reconsider your stand.

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d. Appeal to the People/Masses

• Argumentum ad Populum
• Normal/common/acceptable proof
• This argument makes an appeal to a persons sense
  of belonging or wanting to belong to a particular
  group
• The point simply is ,You should
• (1) be suspicious of arguments based largely upon
  their current popularity,
• (2) keep your mind operating when you are offered
  traditional information, and
• (3) never offer as a proof the fact that
  something is popular.

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d. Appeal to the People/Masses

• Examples
• You really must buy one of these shirtsits the
  latest style, and everybodys wearing them. You
  dont want to be left out, do you?
• Information Technology must be the best major
  because twice as many people major in it as in
  any other field.
• 85 of college students smoke pot, says
  psychiatrist. --That's reason enough, Emil.
  Here, have a joint.
• A million people have bought Magic Cream, so you
  know they must be good.

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d. Appeal to the People/Masses

• Examples
• Virtually the whole country now believes in
  Aswangs, so they must exist.
• Youre behind the times. Getting drunk is now
  accepted as normal at every party.
• Come on, Mary Jane. Everybodys doing it.
• More people use Head and Shoulders than any other
  brand.
• All the others in the class want the party in the
  gym, so don't you think we should have it there,
  too?

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e. Appeal to Pity

• Argumentum Ad Misericordiam
• Ignores the point at issue and appeals, instead,
  to our instinct to have compassion on the
  unfortunate.

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e. Appeal to Pity

• Ex. Plea for Euthanasia
• I have watched three loved ones and a dear friend
  die slowly and horribly of cancer. I saw their
  flesh turn yellow and shrivel into a hanging mass
  of vicious sickly design. I watched the light of
  reason die in their eyes and haunting madness
  take its place. I heard their shrieks of agony
  and their desperate plea for death when opiates
  ceased to deaden their pain The Bible says,
  Blessed are the merciful, for they shall obtain
  mercy. Let the law-makers take this page and
  apply it in their courtrooms.

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BEGGING THE QUESTION

• Petitio Principii
• Consists in assuming under some form or other the
  conclusion that should be proved and then using
  it as a premise to prove the very same
  conclusion.

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BEGGING THE QUESTION

• Examples
• Whiskey causes drunkenness because it is
  intoxicating.
• The soul is immortal because it cannot die.
• Morphine induces sleep because it has soporific
  effects.

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BEGGING THE QUESTION

• Many intelligent people believe in ghosts. This
  is clear because several intelligent people told
  me so. And I know they were intelligent because
  they all believed in ghosts.
• All of the best economists follow Keynes. Joseph
  Line told me, and he's clearly one of the best
  economists because he follows Keynes.
• The fossils in this stratum are 200 million years
  old. How did I date them? Well they are in a
  stratum of that age. How do I know the stratum is
  that old? Because it contains these fossils,
  which are found in strata of that age.

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BEGGING THE QUESTION

• The premises and the conclusions state exactly
  the same thing and differ from one another only
  verbally.
• Things are worse than before because they are not
  as good as they used to be.
• I think Erap is guilty. Why? Because I think he
  did it.
• This is also seen in vicious circles

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FALSE CAUSE

• Consists in assuming a cause or reason for a
  thesis that which in reality is not.
• Post hoc, ergo propter hoc (after this,
  therefore because of this)
• Night comes before day therefore night causes
  day.
• I got well after praying to Medicus Typoos, the
  god of health. Therefore I got well because of
  praying to this god.

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COMPLEX QUESTION

• Have you stopped beating your wife?
• Have you stopped smoking?
• Consists in asking either a multiple question as
  though it were a single question, and then
  demanding a simple yes or no for an answer and
  thus tricking someone into making admissions he
  did not intend.

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COMPLEX QUESTION

• Mr. Glass, did you or did you not visit the bank
  that morning--as our witnesses have
  established--and then rob it later that
  afternoon? Just answer yes or no.
• Are you planning to quit your job and thereby
  doom yourself to failure and despair?
• Don't you think steamed lobster, boiled ox eyes,
  and steak with mushrooms are delicious?
• Aren't you against immoralities like lust,
  kissing, and adultery?

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COMPLEX QUESTION

• How often do you cheat on tests this year?
• How do you account for your incompetence?
• Why did you cause the Smiths' divorce?
• Why do you want war?
• Are you trying to impose your outdated standards
  on me?
• Do you expect me to believe that lie?
• Where did you hide the murder weapon?
• Who made God?
• Have you always been such a fanatic?
• Why do you always commit logical fallacies when
  you talk?
• Why won't you be convinced by obvious truth?

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CONSEQUENT

• Inferring that an antecedent is true because its
  consequent is true, or that a consequent is false
  because its antecedent is false.
• Example
• If Popo is sick, then he will not look well.
• But Popo does not look well.
• Therefore Popo is sick.
• If Popo is sick, then he will not look well.
• But Popo is not sick.
• Therefore Popo looks well.

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CONSEQUENT

• Example 2
• A dolphin is an intelligent being
• Man is an intelligent being
• Therefore man is a dolphin.
• A dolphin is an intelligent being
• Man is not a dolphine
• Therefore man is not an intelligent being.

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NON SEQUITUR

• It does not follow.
• It is a series of true but unrelated propositions
  that simulate the structure of a syllogism.
• Ex.
• God is good.
• Satan is bad.
• Therefore man is good.

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APPEAL TO IGNORANCE

• Argumentum ad Ignorantiam
• Infers that a statement is false because it
  cannot be proved, or true because it cannot be
  refuted.
• It follows this pattern
• This is evidence that must be accepted (denied)
  because it cannot be refuted.

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APPEAL TO IGNORANCE

• Example
• There must be ghosts because no one disproved it
  yet.
• Lucifer lives in the core of the sun. If you want
  to disprove it then give me a picture of you
  inside the solar core.

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SUMMARY (Q A)

• What is a fallacy?
• It is an error in reasoning.
• What are the types of fallacies?
• Formal Informal
• What are material fallacies?
• What are the two main types of material
  fallacies?

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SUMMARY (Q A)
FALLACIES
Accident Irrelevant Conclusion Appeal to
Authority Appeal to Fear Appeal to the
Majority Appeal to the Person Appeal to Pity
Affirming the Consequent Denying the
Antecedent Begging the Question False
Cause Complex Question
FORMAL
INFORMAL

• Equivocation
• Amphiboly
• Composition
• Division
• Accent
• Figures of Speech

Fallacies of Language
Fallacies not of Language