Fallacies
Ignorance is not bliss…
What is a fallacy?
• an error in the reasoning process
• jumping to a conclusion
• an appeal that does not support an argument
The three criteria for reliable reasoning:
• sufficiency
• relevance
• acceptability
Inductive Reasoning
• a general conclusion based on specific evidence
• conclusion goes beyond observations that led to it
• there is always a gap between evidence and conclusion
(called an inductive leap)
• we use the three criteria to try and minimize the gap
• we use questions to test the quality of an induction
• we use logical fallacies to eliminate errors in reasoning
Inductive Reasoning
• is the claim a clear one?
• is the claim a strong one?
• does the hypothesis account for all the facts?
• do you know any relevant facts which conflict?
• does another hypothesis also explain the same facts?
• what further evidence is needed for support?
• what is the source of the evidence?
Catalogue of Inductive Fallacies
Hasty Generalization:
an argument in which the premises
fail to provide sufficient support for the claim. It is a vast claim
made with insufficient evidence
• Teachers have it made. I have a cottage next door to a teacher, and all he
does all summer is swim, sail, and relax in the sun
• When I was in Detroit last week, this huge black guy mugged me.
Blacks should be sent back to Africa.
• President Clinton’s scandal just shows that politicians really have no
morals.
• I read an editorial in the Sault Star about teens that was totally biased.
That paper is useless!
• Old people should have their driver’s licenses suspended. Some old geezer
almost mowed me down in the parking lot.
Catalogue of Inductive Fallacies
Non Sequitur:
the premise is irrelevant and therefore does
not prove the claim. The claim does not follow logically from the
reasons
• The Minister of Health for Canada was asked to investigate the validity of
the nutritional claims made by Kellogg’s for their product Corn Flakes. The
response in parliament was:
“As for the nutritional value of Corn Flakes, the milk you
have with them has great nutritional value.”
• A doll sold at Christmas was found to have a sharp spike protruding from its
neck when the head was removed (which children did quite easily). When a
complaint was received by Consumer Affairs, the response was:
“All the legislation in Ontario won’t protect a child from
the normal hazards of everyday life.”
• Why can’t my curfew be 1:00 a.m.? Brian’s mom lets him stay out ‘til 1:00.
• Avatar is the best movie I’ve ever seen.
It will definitely win best picture at the Academy Awards.
Catalogue of Inductive Fallacies
Problematic Premise:
This fallacy occurs when one or more
of the reasons is unacceptable because of lack of authority or lack
of truth. An undefended reason which requires defense is labelled
problematic.
• Many young people who today hold responsible jobs were once the
recipients of good beatings from their parents. If there are any bleeding
hearts out there who think this is harsh, let them read Proverbs in the Bible.
“Spare the rod, spoil the child”.
• People should be able to go out in public without clothes on. I heard
Howard Stern say so on his show. Man, I love that guy.
• We have too many laws in Ontario. People are tired of being controlled. If
we just let the people follow their instincts, their good human nature will
prevail and they will do the right thing. We should get rid of all those
restrictive laws!
• You had better be good and noble in this life, because if you aren’t, you’ll
be reincarnated as a dung beetle in your next life.
Catalogue of Inductive Fallacies
Causal Connection:
In this fallacy, two events are connected
without proof in a cause/effect relationship. One thing is believed
to have caused the other to happen without proof.
This fallacy is also known as post hoc ergo propter hoc (after this,
therefore, because of this)
• I don’t wanna say nuthin, but I know he didn’t have a drinkin’ problem
‘fore he met her.
• She’s lovely! She’s engaged! She uses Oil of Olay!
• Ever since we changed to Celsius, our weather has gotten colder.
• any and ALL superstitions are causal connections.
• Sex education leads to promiscuity, unwanted pregnancies, and infidelity.
• You shouldn’t teach critical thinking in India because it will cause the
breakdown of their social system.
Catalogue of Inductive Fallacies
Slippery Slope:
This fallacy is a causal connection taken too
far, often indicating a worst-case scenario in “if this continues,
then this will happen” mode. An argument is slippery when it
designates a first and last step in a causal chain, when the
intervening steps have not occurred.
• Smoking marijuana leads to harder drugs like crack and then you’re dead.
• If we let women become CEOs, you can kiss corporate America good-bye.
• Don’t stop reading your Bible. Before long, you’ll be breaking all of the
commandments with a blatant disregard for human life.
• If you have no problem with gum chewing in class, then why not let
students eat and drink as well? Hell, let’s just destroy the blackboards, bring
in a disco ball and they can bump and grind naked in anarchic atavism.
Catalogue of Inductive Fallacies
Red Herring:
This fallacy is also known as distraction, a form
of non sequitur, which puts up a smoke screen to cloud the issue.
Sometimes the support shifts to another point entirely to lead the
reader astray.
• Under-aged drinking laws should definitely be tougher. Drunk driving laws
are even worse because other people’s lives are at stake. Death by car? You
may as well just give people automatic weapons. It’s ridiculous.
• Yes the water in Walkerton tastes a bit funny, but did you know that those
darn teachers, who are public employees, paid by your tax dollars, are
making gross amounts of money working from only 9:00 to 3:00? Plus they
get all the major holidays off? What gives?? (Mike Harris)
• English? Pfftt… who needs that? I’m never going to England. Uptight,
mannerly idiots who are engrossed in their glorious soccer team instead of
the fact that they have bad teeth. Big book of British smiles anyone?
• There’s no way O.J. did it. He is in the Football Hall of Fame. He’s also an
actor. Did you see him in Airplane? Actors are such great people.
Keanu Reeves is awesome!
Catalogue of Inductive Fallacies
Straw Man:
this fallacy is a misrepresentation of someone
else's position so that it can be attacked more easily (i.e.) a
“straw” version. After the misrepresented position is attacked
and defeated, the arguer concludes that the original position has
been demolished.
• Abortion is murder. (Now spend 10 minutes proving that murder is awful,
then come back at the end and say again that abortion is wrong…)
• What I object to most about those people who oppose capital punishment is
that they believe that the lives of convicted murderers are more important
than the lives of the police and prison guards who protect us. But, obviously,
since the lives of those who protect us are of the greatest value, no one
should oppose capital punishment.
• “I'm a very controversial figure to the animal rights movement. They no
doubt view me with some measure of hostility because I am constantly
challenging their fundamental premise that animals are superior to human
beings.” (Rush Limbaugh)
Catalogue of Inductive Fallacies
The following 5 fallacies are the result of pre-judgment or prejudice.
Judgment is the process of reaching a conclusion after a consideration of
the facts. Prejudice is the process of reaching a conclusion before
consideration of the facts; hence, it is illogical.
Labelling:
This fallacy is name-calling. A label is attached to a
person, thing, or issue which causes it to be pre-judged negatively.
Labels are easy to apply but difficult to remove.
• People who disagree with our policies are ignorant, anti-Canadian dorks.
• Shows like Ellen should be taken off the air – she’s just a faggot.
• CSI Miami is the stupidest show I’ve ever watched. David Caruso is a tool.
• Some of Ontario’s laws are Draconian – our leaders are just a bunch Fascists.
• I don’t agree with your views on abortion.
You’re an idiot and your friends are tramps.
Catalogue of Inductive Fallacies
Stereotyping:
This fallacy occurs when a person has an
unvarying conception of a person, group, idea, etc. which allows
for no individuality or critical judgment. It is the placing of people
into pre-conceived slots in your mind.
• Don’t expect much from that guy. He goes to the Hank.
• Americans annoy me. They are loud, arrogant, obnoxious people.
• That basketball team must be awesome. Look at all the black dudes.
• We should get rid of welfare. Those people are just milking the system.
• Females shouldn’t take up space in university math classes. They belong in
easier subjects like art, music, or history .
Catalogue of Inductive Fallacies
Ad Hominem:
This fallacy is an attack on the individual
instead of the issue involved. The person’s character, nationality,
religion, associates, etc. may be attacked.
• That guy shouldn’t run for office. His wife is an alcoholic.
• What does he know about social responsibility? He just got out of prison.
• It’s easy for you to condemn abortion. You can’t have children.
• Chretien wasn’t a good prime minister. He couldn’t even speak properly.
• Harper can cut all the federal programs he wants to – he’s a millionaire.
It won’t affect him at all.
Catalogue of Inductive Fallacies
Ad Populum:
This fallacy is an appeal to the emotions or
prejudices of a large group (a team, a school, a country, a
nationality). It is also termed mass appeal.
• Decent, upright citizens will not listen to a word he says.
• Our television is made in Canada, by Canadians, for Canadians.
• The polls suggest the Liberals will win by a landslide. Join the winning team!
• Anyone who is the least bit patriotic will vote against Quebec’s separation.
• Only an idiot would argue with Flood.
• Any teacher who won’t join the protest is a traitor to our cause.
Catalogue of Inductive Fallacies
Transfer:
This fallacy is a transfer of an idea, feeling, fame,
infamy, etc. from one thing to another, without any logical
connection. It is a borrowing of prestige or ill-fame and applying it
to an unconnected issue.
• Wayne Gretzky eats Wheaties – you should too.
• We ought to get out of the U.N. Churchill warned us about foreign alliances.
• The NDP believes in high income taxes, just like the Marxists…
• Bell Telephone ads, like the one where an old man receives a call from his
grandson who is on the beach at Dieppe where his grandfather fought in the
war. He thanks his grandfather for fighting for freedom and are tears aplenty.
• Beautiful people used to sell all kinds of products.
• Cut my hair? That sounds like something Hitler would say…
Catalogue of Inductive Fallacies
False Analogy:
Analogies are used to clarify or explain ideas.
When a comparison of two objects (or events) which have at least
one area of similarity is used as proof in an argument, the analogy
becomes false. There are more dissimilarities than similarities.
• Employees are like nails. Just as nails must be hit on the head in order to
make them work, so must employees.
• Government is like a business. Just as business must be a moneymaking
enterprise, so must government.
• Minds, like rivers, can be broad. The broader the river, the shallower it is.
People with broad minds are shallow.
• Smoking is all right, so long as you moderate it. Too much of anything is
harmful. Heck, too much applesauce can kill you…
• Don’t worry about your boyfriend. So he dumped you. Men are like
subways… a new one will come along in 7 minutes.
Catalogue of Inductive Fallacies
Ad Misericordiam:
This fallacy is also known as a sob story. It
is an irrelevant appeal to pity or sympathy. There are legitimate
appeals – “Save the Children” campaigns with pictures of real
starving children are relevant.
• Don’t send me to prison. I have a wife and six kids to support.
• Sirrrr… please postpone our fallacy test. We’ve been loaded down with
work, October is depressing, our parents don’t understand us, blah blah blah..
• My client shouldn’t be convicted of murdering his parents.
He had an unhappy childhood.
• You have to give me an “A”. I need it to get into Med school. My entire life
will be ruined if I don’t get an “A”.
• We can’t possibly pay all those negligent death claims. The airline will fold.
Catalogue of Inductive Fallacies
Black & White Thinking:
This fallacy oversimplifies an issue
by polarizing it into extremes, into an either/or situation. It fails
to recognize “gray” or “middle” areas in an issue.
• Listen. Either we ban pornography or we let everybody see it.
• You’re either deaf or stupid. Which is it?
• Are you sane or insane?
• The human race is evil by nature or inherently good. Pick one.
• Women! They’re either yelling at you because of some misdirected moonblood aggression or they’re snuggling up all nice and cozy ‘cause they want
something…
• Of course abortion is a complex issue, but in the end, it stays or it goes.
So are you pro-life or pro-choice?
Catalogue of Inductive Fallacies
Fallacy of the Beard:
This fallacy oversimplifies an issue by
failing to recognize differences within the issue. An issue is
simplified by seeing one side only, often resulting in sweeping,
unsupported, opinionated statements.
• All murderers should be executed.
• Abortion is wrong and no woman should be allowed to have one.
• All art is subversive and all artists should be arrested.
• Television is a blight upon our society and should be strictly censored.
• Men are slime!
• Blacks have natural rhythm.
Catalogue of Inductive Fallacies
Ad Baculum:
This fallacy is also called appeal to force or scare
tactics. There is a threat of unpleasant conditions if the individual
does not agree with the situation.
• You had better agree with the Director if you expect to keep your job.
• You better stop performing abortions or one day you might just find out how
much you value your family.
• Accept the truth of the Catholic Church or face the rack. (Inquisition)
• The jury better find O.J. innocent or there will be rioting in the streets.
• Our paper certainly deserves the support of every German. We shall
continue to forward copies to you and hope you will not want to expose
yourself to unfortunate circumstances. (Nazi notice to readers who let their
subscriptions to the Party newspaper lapse.)
• Voting “yes” for the new Iranian constitution will appease the will and wrath
of God Almighty. (Ayatollah Khomeini)
Catalogue of Inductive Fallacies
Complex Question:
This fallacy occurs when two otherwise
unrelated points are combined as a single proposition wherein the
individual is expected to accept or reject both points when in
reality one may be acceptable and the other not.
It is often termed a loaded question.
• Do you support freedom and the right to bear arms?
• Have you stopped beating your wife?
• How can you be so stupid?
• When are you gonna grow up?
• Have you stopped cheating on your math tests?
• When are you going to become responsible?
Catalogue of Inductive Fallacies
Neglected Aspect:
This fallacy involves the selective omission
of information necessary for making a valid judgment. It is usually
information damaging to the argument which is omitted.
• Nuclear power is a great benefit to mankind. It supplies great sources of
energy and is used in medical treatment.
• Our foreign policy is a great success. Our relations with Britain, the U.S.,
and France have never been better.
• Mom, can I go to the party at Sue’s? Her parents are going to be there.
(for the first hour only…)
• The U.S. performed very well at the Nagano Olympic winter games. We won
women’s hockey gold.
• Canada’s record on human rights is the envy of the world.
We are a true democracy.
Catalogue of Inductive Fallacies
Begging the Question:
This fallacy assumes the validity of
the claim instead of offering valid reasons to support it. It also
takes the form of circularity in which the reason is merely the
claim restated..
• Is it right that we prosecute someone who practices euthanasia?
Yes. The law is the law.
• Foreigners are unreliable because they’re not Canadians.
• Should the U.S. bomb Iraq or wait for diplomacy to work?
Diplomacy doesn’t work – Nuke ‘em!
• Dubya is incapable of making good decisions because he is incompetent.
• God must exist.
How do you know?
Because the Bible says He does.
Why should I believe the Bible?
Because, it’s the word of God.
Catalogue of Inductive Fallacies
Ad Ignorantiam:
this fallacy is an appeal to ignorance where
someone attempts to argue something false because it cannot be
proved true (or vice versa). It misplaces the burden of proof.
• I have an invisible fire-breathing dragon in my garage…
Until you prove this is false, my claim is true.
• No one has ever proved 100% that UFOs exist, therefore they don’t exist.
• Obviously UFOs exist – no one has been able to prove that they don’t.
* note that appeals to ignorance can work in either direction
• No further questions on fallacies? Good. You must be ready for a test.
• Of course he’s a communist. There’s nothing in his file to say that he isn’t.
• I definitely have ghosts at my camp – I got a weird reading on an EMF meter.
No way dude. It’s probably just from nearby electric cables.
But there's no electricity in the area.
OMG bra, it’s a ghost!!