Logical Fallacies

Logical Fallacies GXEX1406 Thinking and Communication Skills

GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Premise & Conclusion Premise: All girls have long eyelashes. Cows has long eyelashes Conclusion: Therefore, all girls are cows Is this statement logically right? GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Is this reasoning logical? Premise: “A cloud is 90% water. A watermelon is 90% water. A plane can fly through a cloud. Conclusion: Therefore, a plane can fly through a watermelon” GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

There is logic in the premise of the statements – BUT the conclusion makes no logical sense. The reasoning is flawed The conclusion is illogical GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

This type of arguments are called Logical fallacies • Fallacy is a mistake in reasoning • A statement or argument based on false inference that causes incorrectness in reasoning • Used to cloud our logical thinking, appeal to our emotions rather than intellect • Often masquerade as logical statements GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Objective of the course • You will be able to identify fallacies • Able to indicate instances or type of fallacy Situations • Found in newspapers, magazines, reports, advertisements GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Why Study Fallacies ? • Able to spot poor reasoning & know why it is wrong • Able to correct other’s mistakes, or refute them convincingly • Supplements your knowledge on logic GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Why Study Fallacies ? • Know when your reasoning in an essay is flawed or questionable • Prevent you from making generalized statements without backing it up with sound evidence GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

3 categories of fallacies • (1) Fallacies that appeal to emotions (total 4) - Claims are made that appeal to emotions rather than reason • (2) Fallacies that distract (total 3) - Claims made to divert attention from the main issue • (3) Other common types (total 5) GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

(1) TYPE 1- appeal to emotions • (a) Appeal to fear/force/scare tactics -ad baculum The claim makes use of threats. The threats are irrelevant to the argument. Therefore the claim is fallacious GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Example: appeal to fear/force/scare tactics • If you don’t finish your vegetables, you will get cancer • If you do not forward this mail to 10 friends, you will face bad luck - (chain mail) • Listerine: kills the germ that causes bad breath GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

WHY FALLACIOUS? - No proof that not eating veges can cause cancer + Not all cancers are caused by not eating veges • No proof that the chain mail causes bad luck - Other factors may also cause bad breath. GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

(1) TYPE 1 • (b) Appeal to vanity/flattery Use flattery to make the reader or listener feel special. Use persuasive language. Often used in advertisements. To entice consumers to buy products or services GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Example: Appeal to vanity/flattery • I don’t moisturize, I don’t tone, I just use Dove! • BMW 3.0Si: for those who deny themselves nothing • SBB blue-chip MasterCard, a radically new way of life GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

WHY FALLACIOUS? • Where is the proof that Dove is 3 in 1? That it moisturizes & tones other than it just cleans ? • Can a car really last for life? • having the new master card may not necessary change your life in a radical way GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

(1) TYPE 1 • (b) Appeal to numbers/ bandwagon /peer pressure Use to solicit group identity Put pressure on individuals to follow the crowd. Often used in adverts - to buy software or hardware or other products & services GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Example: Appeal to numbers/bandwagon/peer pressure • Millions of people smoke. Therefore smoking must not be bad for people. • All the really smart people watch University Challenge. You should watch too. • Classical music is really neat - but like my friends I prefer Linkin’ Park. We are not nerds. GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

WHY FALLACIOUS? • Just because millions of people do something is a poor basis to say that the action is right. • Not smart people also watch that TV show! • You don’t have to follow your friends in your choice of music to listen to. Where is the proof that classical music lovers are nerds? GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

(1) TYPE 1 • (b) Appeal to pity (ad misericodium) Use pity to establish the truth of a conclusion Use language to evoke compassion to induce the listener to accept the claim GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Example: Appeal to pity • You should hire him as a coach of our football team because he broke his leg and cannot play big time football anymore. • We should re-elect Encik Fauzi as our MP because his wife just died and his crippled mother lives with him. GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Why Fallacious? • Pity does not serve as evidence for a claim. Therefore the claim is fallacious GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

TYPE 2 - Fallacies that distract (total 3 - Claim that diverts attention from the main issue) • (a) Ad Hominem / against the person Sometimes called - fallacy of opposition Attacks the person’s personality, beliefs, affiliation, ethnicity to reject a claim GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Example: Ad-Hominem • Encik Latif just divorce his wife. How can his proposal be any good? • How can you vote for Salmah as prefect when she is related to the Headmistress? • You agree that the government should increase on military spending because your father works in a munitions factory. GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Why Fallacious? • The character or circumstance of the person has no claim on the truth of the claim. Encik Latif divorcing his wife has got nothing to do with his working ability Salmah may have the makings of a good prefect even though she is related to the head mistress. GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

TYPE 2 • (b) Red Herring An issue brought into the picture to divert the listener’s or reader’s attention from the real issue This happens a lot in meetings and group discussions. Be aware of this! GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Example: Red herring • Why worry about the Pandas becoming extinct when we have a large number of homeless in our own country? • Why should we donate to the Iraq war when we still have people living in poverty? GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Why Fallacious? • One issue is not related to the other. Therefore the first claim cannot justify the second claim. The extinction of pandas and the homeless are two separate issues The contribution to Iraq war and the plight of the poor are two separate issues. GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

TYPE 2 • (c) Straw Man Oversimplify an evidence to support a claim. The simplification, therefore cannot support the claim GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Example: Straw Man & why fallacious • Those who favor gun control also favor disarming the police This is oversimplifying the issue. The first claim is not strong enough to support the second claim. GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Example: Straw Man & why fallacious • What women in her right mind would support total equality with men. No women wants the right to go to war or the right to pay alimony Oversimplify the issue. Equality does not mean for every situations! GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

TYPE 3 - Other common fallacies • (a) Begging the question (circular argument) The claims in the premise is again drawn in the conclusion. Redundant Repeating an issue (going in circles) The argument does not go anywhere! GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Example: begging the question & why fallacious? • My argument must be correct because I am the smartest student in the class. The conclusion merely restate the premise. Being smart does not mean that you are correct. GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Example: begging the question & why fallacious? • Murderers should be executed because they are killers! The conclusion merely restate the premise. Murderers are killers by definition. So, what is the justification why killers must be executed? GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Example: begging the question & why fallacious? • The bible is the word of God because it says it is. Whether or not the bible is the word of God is a matter of personal faith. The statement should be written as: The Bible says that it is the word of God. The word of God cannot be false. Therefore, the Bible is the word of God. GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

TYPE 3 - Other common fallacies • (b) Slippery slop (snowball argument/ domino theory) Suggests to the listener that if one action is taken, it will lead to similar actions & the end result is negative or undesirable Assumes a chain reaction of cause-effect of events GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Example: slippery slope & why fallacious? • Let one student disrupt my lecture, then other students would want to ask & I therefore cannot complete my lecture in time. Student’s interruptions may disrupt a lecture BUT not all lectures are delayed because of students disruptions. GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Example & why fallacious? • President Richard Nixon - We have to win in Vietnam or the entire SEA will become communist Winning the Vietnam war might have saved Vietnam from Communism BUT not all communist state are dependent of the success of the Vietnam War. GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

TYPE 3 - Other common fallacies • (c) False dilemma or black / white argument/ either -or A limited number of opinion is given when in reality there are more options An illegitimate use or the word “or” GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Example of False Dilemma (black/white) & why fallacious? • FSKTM Love it or leave it. Should have been written as: One of the ways to excel in FSKTM is to love the life here. Hating it would affect your studies and may result with you having to leave. GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Example of False Dilemma (black/white) & why fallacious? • Stop smoking or die young. Fallacious because death can be caused by other factors not just by smoking. Should have been written as: One of the ways to avoid dying young is to stop smoking as smoking might affect one’s health. GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Example of False Dilemma (black/white) & why fallacious? • Either go to college or forget about getting a good job. Fallacious because good jobs are not dependent on going to college alone. Should have been written as: Going to college and getting a degree is one means of getting a good job. GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

TYPE 3 - Other common fallacies • (d) Hasty generalization This is the chief error made by many. Leaping to a conclusion without a strong or large enough justification. GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Example of Hasty generalization • Feminists hate men. Ramlah is a feminist. Ramlah hates men. • I notice that my fat friend is jolly. Therefore all fat people are jolly. • All pop stars are rude. I asked Elton John for his autograph at a restaurant and he told me to get lost. All the arguments are based on insufficient evidence & there fore are not valid. GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

TYPE 3 - Other common fallacies • (b) Burden of Proof (Appeal to ignorance) Premise: If something has not been proven as false, the claim must be true. Shifts the burden the other party to prove in order to make a claim. GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Example of burden of proof & why fallacious? • Since you cannot proof that ghosts does not exist, then they do exist. • Since scientists cannot proof that global warming will take place, it probably wont. • The new experimental drug must be working because not a single patient has returned to complain. GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

SUMMARY OF FALLACIES • (1) Fallacies that appeal to emotions (total 4) • - Claims are made appeal to emotions rather than reason • Appeal to Fear/Force/ Scare tactics or ad baculum • Appeal to Vanity/Flattery • Appeal to Numbers/ Belief/ • Bandwagon/Peer pressure • Appeal to Pity (Ad misericordium) GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

3 categories of fallacies • (2) Fallacies that distract (total 3) - Claims made divert attention from the main issue • Ad hominem (attack/against the person) • Red herring • Straw Man GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

3 categories of fallacies • (3) Other common types (total 5) • Begging the question (circular arguments) • Slippery slope (domino theory) • False dilemma (either- or) • Hasty generalization • Burden of proof GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

THE END THE END GXEX1406 Thinking and Communication Skills – Week 12 Logical Fallacies

Logical Fallacies