errare

1

• errare
• humanum
• est
• (to err is human)

2
FALLACIES
3
INDUCTIONvs.DEDUCTION
PART 1
4
INDUCTION

• (S ? G)
• think increase (induction, increase)
• from specific/particular instance or instances
• to generalization
• quantity () sufficient of items or people
  asked, sufficient data (stats)
• quality reliable source (authority), accurate
  in-depth observation
• PROBABILITY, not certainty

5
INDUCTION

• BAD EXAMPLE
• You compare the prices of 4 textbooks at store 1
  with those at store 2 and notice that the prices
  are higher at the former than at the latter. You
  conclude that store 1 is more expensive.

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INDUCTION

• GOOD EXAMPLE
• A television documentary focuses on the issue of
  unwed teenage mothers in a particular city
  neighborhood. Four girls are interviewed and
  followed for several days. Then, a noted and
  respected sociologist who has studied thousands
  of unwed teenagers is interviewed, and she claims
  these four girls are representative of the many.

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INDUCTION

• INDUCTIVE FALLACIES
• wrong use of data
• insufficient sample (not enough people
  interviewed)
• ignore evidence (other possibilities)

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DEDUCTION

• (G ? S)
• think decrease (deduction, decrease)
• from inductive generalization
• to conclusion

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DEDUCTION

• 3 Propositions of a Deductive Syllogism
• 1) MAJOR PREMISE
• inductive generalization
• All
• All humans are mortal.
• (syllogism Greek, to calculate using logic)

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DEDUCTION

• 3 Propositions of a Deductive Syllogism
• 2) MINOR PREMISE
• statement about a specific member of that group
• This
• My English professor is a human.

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DEDUCTION

• 3 Propositions of a Deductive Syllogism
• 3) CONCLUSION
• Major Premise Minor Premise Conclusion
• 1 2 3
• S ? G, G ? S
• Therefore
• Therefore, my English professor is mortal.

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DEDUCTION

• If the MAJOR premise absent or faulty
  induction,
• if the MINOR premise faulty observation
  concerning the individual at issue,
• then conclusion faulty, invalid.
• HOWEVER, if the opposite is true, then the
  conclusion is a valid, strong one stronger than
  induction.
• CERTAINTY, validity, truth

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DEDUCTION

• BAD EXAMPLE
• A man is sitting opposite you on a train. He has
  what appears to be chalk dust on his fingers, and
  you conclude that he is a teacher.

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DEDUCTION

• BAD EXAMPLE
• Major premise All men with chalk on their
  fingers are school teachers.
• Minor premise This man has chalk on his
  fingers.
• Conclusion Therefore, this man is a school
  teacher.

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DEDUCTION

• BAD EXAMPLE
• Faulty Conclusion
• other occupations
• draftsmen, carpenters,
• tailors, artists
• other powders
• flour, confectioners sugar,
• talcum, heroin

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DEDUCTION

• DEDUCTION your INTRODUCTORY PARAGRAPH
• Funnel Effect, Inverted pyramid
• G ? S,
• syllogism, conclusion of syllogism thesis
  statement
• Major premise Reducing awareness of social
  differences is a desirable goal for the school.
  
• Minor premise A uniform dress code would help
  to achieve that goal.
• Conclusion/thesis Therefore, students should
  be required to dress uniformly.

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DEDUCTION

• DEDUCTIVE FALLACIES
• failure to follow the logic of a series of
  statements
• an error in one premise or both premises
• other possibilities exist that were not taken
  into consideration
• reliance upon support other than facts

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FACTSvs.IMPLICATIONS, ASSUMPTIONS, INFERENCES
PART 2
OCCAMS RAZOR
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FACTS vs. OTHERS

• 1) FACTS
• provable, verifiable
• probable
• primary evidence
• senses
• science
• secondary evidence
• testimony secondary (beliefs, ideas not from
  senses)
• historical evidence (documents, testimony,
  articles)

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FACTS vs. OTHERS

• 2) IMPLICATIONS
• unspoken message
• suggestion
• with indirect words
• SUBTEXTS
• Rhetorical Questions, Mincing Words

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FACTS vs. OTHERS

• 3) ASSUMPTIONS
• supposition
• idea taken for granted
• based on prior knowledge
• based on little knowledge

22
FACTS vs. OTHERS

• 4) INFERENCES
• logical deduction
• based on evidence or observation
• educated guess

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FACTS vs. OTHERS

• ASSUMPTION vs. INFERENCE
• assumption based on belief
• inference based on sense data or premises
• IMPLICATION vs. INFERENCE
• implication made by the speaker
• inference made by the listener

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FACTS vs. OTHERS

• Implications, Assumptions, Inferences
• not facts
• you fill in the gaps
• you make connections
• you supply missing data
• you draw conclusion without all of the
  information/facts

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OCCAMS RAZOR

• RULE OF SIMPLICITY (in textbook)
• When there are competing possibilities, choose
  the answer that requires the fewest assumptions.
• Cut through the obfuscation (BS) and choose the
  solution that would not appear on The X-files .
• The simplest solution is often the best.

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THE FALLACIES
PART 3
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I. INSUFFICIENT EVIDENCE
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INSUFFICIENT EVIDENCE

• FAULTY INDUCTION Inductive Fallacies
• quantity not enough evidence upon which to draw
  a reasonable conclusion
• quality unreliable data or sources
• bad Ethos
• implications, assumptions, inferences (not facts)
• FAULTY DEDUCTION Deductive Fallacies
• flawed Major Premise (generalization)
• flawed Minor Premise (specific, observation)

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INSUFFICIENT EVIDENCE

• 1) OVERGENERALIZATIONS
• hasty, false, sweeping generalizations
• dicto simpliciter (spoken simply)
• implies ALL
• uses INDEFINITE PRONOUNS
• all, everyone, everybody
• no one, nothing
• everything, anything, always

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INSUFFICIENT EVIDENCE

• 1) OVERGENERALIZATIONS
• EASILY DISPROVED too many exceptions
• and too many complications (life too complex)
• QUALIFY WITH
• many, some, few
• usually, often, in my experience
• DANGER with qualifying too many maybes in your
  writing may make you look indecisive

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INSUFFICIENT EVIDENCE

• EXAMPLES of OVERGENERALIZATIONS
• stereotypes, prejudices, superstitions
• racism, ageism, sexism
• Teenagers today are fat and lazy.
• Men dont cry.
• Hasty generalization Jim Bakker was an
  insincere Christian. Therefore, all Christians
  are insincere.
• Sweeping generalization Christians generally
  dislike atheists. You are a Christian, so you
  must dislike atheists. (senior citizens, Asians,
  guys, Americans materialistic, war-mongers)

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INSUFFICIENT EVIDENCE

• 2) STACKING the DECK (a.k.a. card stacking)
• poker metaphor
• dealing yourself a good hand
• stacking the card deck in your favor
• selecting only the data that supports your
  position
• ignoring contradictory data
• (only 1 side of the issue)
• (needs other side/s of the issue)
• news bias, politicians, tobacco/oil industries
• fraudulent, misleading

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INSUFFICIENT EVIDENCE

• EXAMPLES of CARD STACKING
• Ninety-five percent of the people I interviewed
  agreed with the Democratic Opposition.
• BUT I only interviewed people at the Democratic
  National Convention!
• According to a Left-Wing Nut magazine poll, the
  Vice President has a low approval rating.
• BUT only those people who readi.e., agree with
  the ideology ofthis publication were polled.

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INSUFFICIENT EVIDENCE

• 3) AD IGNORANTIUM
• since cannot disprove (or prove), then must be
  true
• assumes a lack of information (ignorance) is a
  source of information (needs more info)
• yet, an absence of evidence is not evidence

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INSUFFICIENT EVIDENCE

• CARD STACKING vs. AD IGNORANTIUM
• Dont be fooled by the ignoring part
• CS purposefully ignores existing evidence
• data that will disprove or weaken that side
• the data does exist but is ignored
• AI uses ignorance as evidence
• uses the lack of existing evidence as evidence
• the lack of evidence the proof
• the data does not exist

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INSUFFICIENT EVIDENCE

• EXAMPLES of AD IGNORANTIUM
• Since the library has no books on Eva Brauns
  intimate relations with Adolf Hitler, then she
  must not have had any.
• Of course the Bible is true. Nobody can prove
  otherwise.
• Of course telepathy and other psychic phenomena
  do not exist. Nobody has shown any proof that
  they are real. (aliens, ghosts)

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INSUFFICIENT EVIDENCE

• 4) POST HOC ERGO PROPTER HOC
• after this, therefore b/c of this
• assumes a causal relationship
• no other explanations
• faulty Cause-Effect relationship
• assumes a later event was caused by an earlier
  one
• simply because of chronology
• needs more info, more research
• B follows A therefore, A causes B

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INSUFFICIENT EVIDENCE

• DISPROVE with (more information)
• prove A and B are merely coincidences
• show how A is merely 1 cause of many
• show how A is not even a significant cause of the
  many
• more than 1 cause of an effect, more than 1
  effect of a cause
• indirect and direct causes
• complexity of life, of situations
• OCCAMS RAZOR
• simpler, more credible answer or explanation is
  best

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INSUFFICIENT EVIDENCE

• PHEPH Superstitions
• ltboston.com gt

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INSUFFICIENT EVIDENCE

• EXAMPLES of P.H.E.P.H.
• superstitions, astrology
• Consider additional causes for the following
• Because you left the milk out last night, it was
  spoiled this morning.
• The Soviet Union collapsed after instituting
  state atheism. Therefore, we must avoid atheism
  for the same reasons.
• A rooster crows every morning, and shortly
  after, the sun rises. Therefore, the rooster
  causes the sun to rise.

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INSUFFICIENT EVIDENCE

• EXAMPLE of P.H.E.P.H.
• After the school principal suspends daily
  prayers in the classroom, acts of vandalism
  increase, and some parents are convinced that the
  failure to conduct prayer is responsible for the
  rise in vandalism.
• Butdecline in disciplinary actions, a relaxation
  of academic standards, a change in school
  administration, changes in family structure in
  the school community.

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INSUFFICIENT EVIDENCE

• Post hoc ergo propter hoc
• after this (subsequency), therefore because of
  this
• Cum hoc ergo propter hoc
• with this (synchronicity), therefore because of
  this
• mistakes a correlation for causation
• overlooks coincidence, others causes
• because of simultaneous occurrence
• Clinton had great economic policies because the
  economy was great during his two terms.

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INSUFFICIENT EVIDENCE

• 5) AD HOC
• for this (specific purpose) impromptu,
  provisional
• an after-the-fact explanation
• does not apply to other situations (for this
  special case alone)
• God cured me of my cancer. But most patients
  with brain cancer die. Why did She save you?
  Are you special? Does She love you more than the
  rest of us? She moves in mysterious ways.
• because God treats all people equally, no special
  treatment
• refuted by more evidence (radiation, medication,
  remission)
• see also God war, God sports

1 time only!
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INSUFFICIENT EVIDENCE

• 6) The Natural Law Fallacy -- Appeal to NATURE
• draws a false analogy between the human and
  natural worlds
• assumes that humans are part of the natural world
  (animals) and should thus mimic animalistic
  behavior
• assumes that whatever is natural or consistent
  with nature is good AND that whatever is
  unnatural is bad
• supplements, herbal remedies
• law of the jungle arguments for genocide,
  capitalism
• Homosexuality is natural because monkeys have
  been observed engaging in homosexual behavior.
  (or the opposite)

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INSUFFICIENT EVIDENCE

• 6) The Natural Law Fallacy -- Appeal to NATURE
• BUT
• natural and nature poorly defined
• just because animals do it (or dont) does not
  mean humans should (or shouldnt) do so
  automatically, necessarily, unquestionably
• naïve environmentalism
• poison ivy, Ebola, climate, eat their young, eat
  bugs
• bathrooms, plumbing, fire, literature, clothes,
  utensils

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II. IRRELEVANT INFORMATION
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IRRELEVANT INFORMATION

• DIVERSIONARY TACTICS
• They introduce ideas that are off-topic.
• Their data is NOT germane to the present case.

Diversions, Distractions from the argument at
hand
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IRRELEVANT INFORMATION

• 1) AD BACULUM
• intimidation
• threat of harm
• physical or psychological
• economical, political, environmental
• extortion, blackmail
• Rather than make a claim, point, or
  counter-argument, I make a threat, which isnt
  discussing the issue at hand.
• Because my evidence is rather weak, I try to win
  the argument with a scare tactic.

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IRRELEVANT INFORMATION

• EXAMPLES of AD BACULUM
• If citizens dont start patronizing downtown
  stores, then businesses will be forced to close
  and then the city will be in ruin.
• If you dont (believe in God, convert to our
  religion, illegalize that practice), then youll
  burn in Hell!
• ... In any case, I know your phone number and I
  know where you live. Have I mentioned I am
  licensed to carry concealed weapons?
• If we make abortions illegal, women will be
  getting butchered again in back alleys. (ad
  misericordiam, slippery slope)

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IRRELEVANT INFORMATION

• 2) AD HOMINEM
• name calling
• (think hombre, hommé)
• personal attack, insults
• attack the person, not the facts or issue
• a way to avoid dealing with the issue
  (diversion)

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IRRELEVANT INFORMATION

• PLEASE NOTE
• A bad person does not necessarily mean a bad
  argument (conclusion, point).
• (even a broken clock)
• Accusations against the person are NOT a fallacy
  IF the characteristics under attack are relevant
  to the argument.
• For example, if a politician is irresponsible
  dishonest in her/his personal life, then it is
  reasonable to think that s/he may be the same in
  public office.

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IRRELEVANT INFORMATION

• EXAMPLES of AD HOMINEM
• What does he know look at the way hes
  dressed.
• What can a priest tell us about marriage since
  hes never been married himself. (AA)
• My doctor is overweight, so why should I listen
  to anything he has to say. (Dr. Adkins)
• I wont see a Jayne Smith movie because shes a
  drug addict. (private life vs. professional
  record)
• Since you dont support gay marriages, you must
  be a homophobe. (racist, sexist)

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IRRELEVANT INFORMATION

• EXAMPLES of AD HOMINEM
• You claim that atheists can be moral yet I
  happen to know that you abandoned your wife and
  children.
• Hitler would be very proud of you (in response
  to practically any conclusion or decision).
• Therefore, it is perfectly acceptable to kill
  animals for food. I hope you wont argue
  otherwise, given that you're quite happy to wear
  leather shoes.
• Of course youd argue that positive
  discrimination is a bad thing. Youre white.

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IRRELEVANT INFORMATION

• 3) FALLACY of OPPOSITION
• name calling
• whatever comes from the opposition is
  automatically wrong AND detrimental
• assumes nothing good could come from those we
  oppose
• Us vs. Them
• EXAMPLE Of course youd say that, youre an
  atheist, hippie, teenager, Democrat . (a member
  of the opposing group)

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IRRELEVANT INFORMATION

• 4) GENETIC FALLACY
• name calling
• assumes where the idea came from affects its
  validity (country, paper, school)
• akin to elitism, snobbery
• we come from our genes,
• genes ? genetic fallacy

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IRRELEVANT INFORMATION

• 4) GENETIC FALLACY
• EXAMPLES
• The quality of those products is poor because
  they come from China (any country).
• Cars made in the USA (any country) are junks.
• Because that idea comes from a community college
  it must be flawed, erroneous, or just plain
  wrong.

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IRRELEVANT INFORMATION

• 5) GUILT by ASSOCIATION
• birds of a feather stick together
• assumes a persons behaviors must extend to their
  friends, to those around them
• EXAMPLES
• Everyone who goes into a bar is an alcoholic.
• Sallys promiscuous, so as her friend you must
  be, too.

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IRRELEVANT INFORMATION

• 6) AD MISERICORDIAM
• an abuse of pity
• manipulation obfuscation (diversion)
• irrelevant
• evoke pitiful image or situation, without basis,
  to distract from the issue
• relies wholly on pity (pathos)

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IRRELEVANT INFORMATION

• EXAMPLES of AD MISERICORDIAM
• photos of kids war, famine, AIDS, disaster
• I couldnt write my paper because my son,
  daughter, mother, girlfriend, neighbor down the
  street was sick.
• I did not murder my mother and father with an
  axe! Please dont find me guilty Im suffering
  enough through being an orphan.

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IRRELEVANT INFORMATION

• 7) AD POPULUM
• appeals to the populace
• biases prejudices, appeals to tradition,
• halcyon days
• tells people what they want to hear, what they
  want to believe (working the audience)
• SLOGANS and SOUND BITES subvert the reasoning
  process because they do not define terms
• which can mean whatever people want them to mean
  or
• whatever people say they mean
• what exactly are family values?!

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IRRELEVANT INFORMATION

• EXAMPLES of AD POPULUM
• sound bites, slogans, bumper stickers, tee shirts
• appeals to patriotism, change for changes sake
• political cartoons, late-night-TV monologues or
  punch lines, Comedy Central shows
• if it appears on poster, tee shirt, bumper
  sticker
• If guns are outlawed, then only outlaws will
  have guns.
• Zippo. Its the grand old lighter thats made
  right here in the good ol USA. (patriotism)
• Freedom isnt free. No blood for oil.
• Guns dont kill people people kill people.
• Just say no.

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IRRELEVANT INFORMATION

• 8) BANDWAGON
• Argumentum ad numerum
• right/valid because popular
• jump on the bandwagon, join the parade
• do because others do peer pressure, group/mob
  identity, conformity
• appeals or refers to NUMBERS
• BUT you can be correct even if no one else agrees
  with you (Copernicus, Columbus)

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IRRELEVANT INFORMATION

• EXAMPLES of BANDWAGON
• Sixty million people cant be wrong.
• Over 5 million Americans have already switched
  to Grizzly Insurance.
• Last December, over 100 million people worldwide
  tuned in to see a television phenomenon dont
  be left out when Knucklehead TV returns in
  March.
• Everybodys doing it anyway, so we might as well
  legalize it (lower the age).

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IRRELEVANT INFORMATION

• Similar to Argumentum ad numerum AND to
  Argumentum ad populum. It consists of asserting
  that the more people who support or believe a
  proposition, the more likely it is that that
  proposition is correct. For example
• The vast majority of people in this country
  believe that capital punishment has a noticeable
  deterrent effect. To suggest that it doesnt in
  the face of so much evidence is ridiculous. Or
  All I'm saying is that thousands of people
  believe in pyramid power, so there must be
  something to it.
• Similar to Appeal to Tradition right/valid
  because its old since its lasted this long, it
  should continue. ex Since the Fiesta Club has
  been an exclusive male-only society since its
  founding at the turn of the 20th century, it
  should continue to exist in the same manner
  form.

65
IRRELEVANT INFORMATION

• 9) PLAIN FOLKS and SNOB APPEAL
• right because popular
• opposite of the Genetic Fallacy
• These are 2 different fallacies, but same coin.
• Plain Folks Appeal do because the ordinary
  person does ( avoid the pretensions of snobs)
• Snob Appeal do because rich/popular/beautiful do
  (celebrity endorsements)

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IRRELEVANT INFORMATION

• EXAMPLES of PLAIN FOLKS SNOB APPEAL
• Why pay fancy salon prices for a shampoo?
• Family values will return America to world
  prominence.
• Mark Twain said, The clothes make the man.
  Naked people have little or no influence on
  society. So, if you want to be a winner, youve
  got to look like a winner, which means you need a
  Rolex watch, Italian shoes, and a Lexus to be
  successful.
• Use the deodorant that professional athletes
  like Illiterate Joe use. (appeals to readers
  vanity)
• Think of 2 diametrically opposed musical genres.
• also known as Argumentum ad lazarum The fallacy
  of assuming that someone poor is sounder or more
  virtuous than someone who's wealthier. This
  fallacy is the opposite of the Argumentum ad
  Crumenam. For example Monks are more likely to
  possess insight into the meaning of life, as they
  have given up the distractions of wealth.

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IRRELEVANT INFORMATION

• 10) AD VERECUNDIAM
• inappropriate use of authority
• assumes because a person is an expert in one
  field that s/he is an expert in another
  (celebrity endorsements)
• OR
• the use of an obscure, hard to find source
• poor or irrelevant credentials, wrong field of
  expertise, no Other Side of the issue (Rogerian
  Method)
• BAD ETHOS

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IRRELEVANT INFORMATION

• EXAMPLES of AD VERECUNDIAM
• Bad
• I play a doctor on TV, so take this new OTC
  pill.
• Isaac Newton was a genius and he believed in
  God, so you should, too.
• Dr. Housenick claims stem cell research for the
  development of cures for various diseases is (is
  not) a worthy venture.
• Because my parents were unavailable, I asked my
  English teacher for permission to stay out late.
• Good
• Dr. Stephen Hawking has concluded that black
  holes give off radiation therefore, there is a
  strong chance that they exist.

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IRRELEVANT INFORMATION

• 11) RED HERRING
• diversion
• skirt the issue obfuscate the truth
• use an irrelevant point or a side issue to lead
  away from the issue at hand

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IRRELEVANT INFORMATION

• EXAMPLES of RED HERRING
• Sure, the Chargers had a bad year, but what
  about the Redskins.
• While it may be true that we withheld vital
  information from the public regarding the
  dangerous side effects of our products, while it
  may be true that we sought ways to enhance our
  products with addictive substances, and while it
  may be true that we profited immensely from all
  this, have you taken into consideration the fact
  that we have given bottled water to disaster
  victims and other acts of community involvement?

71
IRRELEVANT INFORMATION

• 12) STRAWMAN ARGUMENT
• a.k.a. Weak Opponent, Scarecrow Argument
• diversion, name calling
• this one has a few different (yet related) sides
  to it

72
IRRELEVANT INFORMATION

• Use or invent a convenient opponent that can be
  attacked (or applauded) without fear of
  retaliation
• an easy target
• to show how strong you are, you hold up a
  Scarecrow slap it around (think WWE)
• I can make fun of famous people because
• theres little chance that theyll come
• from Hollywood (e.g.) to rebut me.
• think of these easy targets
• Britney Spears, KKK, Nazis

73
IRRELEVANT INFORMATION

• Use or invent a generic/vague group or label
• no real person involved
• no true subject of the argument is identified
• label unfair, inaccurate, manufactured solely
  for the argument
• stereotypes, overgeneralizations
• (based on personal biases/prejudices)
• could be positive group
• the heroic war dead, brave immigrants
• (no specific person indicated)

74
IRRELEVANT INFORMATION

• Attack your opponents weakest possible
  argument, one s/he is not even offering
• put words into the opponents mouth
• similar to 1, in that I set up an easy opponent
  (their weakest possible argument) just so I can
  easily knock it down (and look good in the
  process)
• like Tu Quoque, Ad Hoc, False Dilemma

75
IRRELEVANT INFORMATION

• EXAMPLES of STRAWMAN
• Richard Nixons 1952 Checkers speech (weakest
  possible argument)
• kids/students today (no real kid/student)
• moral majority (who are these people?)
• welfare cheats (do they really exist?)
• liberal media (is it really? all? proof?)
• To be an atheist, you have to believe with
  absolute certainty that there is no God. In order
  to convince yourself with absolute certainty, you
  must examine all the Universe and all the places
  where God could possibly be. Since you obviously
  haven't, your position is indefensible. (weakest
  argument)

76
IRRELEVANT INFORMATION

• 13) TU QUOQUE (too kwo-kway)
• you did it too
• justify actions because accusers are supposedly
  guilty of same crime
• 2 wrongs make 1 right (see AD POPULUM)

77
IRRELEVANT INFORMATION

• EXAMPLES of TU QUOQUE
• You did it too when you were my age.
• quote Its ok that I dis white people on my
  show because theyve been doing it to us for
  years.
• How can you criticize my driving when youve had
  five accidents yourself?
• Why shouldnt I cheat on my taxes? Everyone else
  does.

78
IRRELEVANT INFORMATION

• 14) OVERSIMPLIFICATION
• like Post Hoc, Overgeneralization
• overlooks the complexity of an issue
• no critical examination of the issue
• narrows complex issue down to single cause
• BUT an issue has more than 1 side (more than 2
  sides)
• legal, moral, religious, political, racial,
  philosophical...
• an effect always has more than one reason/cause

79
IRRELEVANT INFORMATION

• EXAMPLES of OVERSIMPLIFICATION
• Kids are fat because they eat too much
  McDonalds.
• The only reason were at war with Iraq is over
  oil.
• An ad populum statement may say, No Blood for
  Oil!
• Its as simple as that.
• Todays college students cant spell because
  of spellcheckers on computers.

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III. AMBIGUITY
81
AMBIGUITY

• These fallacies have statements that are either
  purposefully or accidentally ambiguous,
  misleading, or confusing.
• Their problem often lies with LANGUAGE
• grammar
• punctuation
• diction
• syntax

82
AMBIGUITY

• 1) AMPHIBOLY
• a.k.a. amphibole
• Latin for ambiguous
• ambiguous, multiple meanings or interpretations
• caused by Bad Grammar
• misplaced modifiers, poor pronoun reference
• misleading statistics
• percentages 89 sounds like much, but not if
  only 5 people were asked

83
AMBIGUITY

• EXAMPLES of AMPHIBOLY
• Her parents watered the flowers, yet they died.
  (confusing PN reference)
• Sam gave Bob his baseball glove. (confusing PN
  reference)
• I shot a bear in my pajamas. (misplaced
  modifier)
• March moved to June.
• Girls slip seen by many.
• 4 out of 5 dentists prefer Trident. (80, only
  5 asked)

84
AMBIGUITY

• EXAMPLES of AMPHIBOLY
• Blind Bishop Appointed to See
• Patient at Death's Door Doctors Pull Him
  Through
• Teacher Strikes Idle Kids
• Lawyers Give Poor Free Legal Advice
• Juvenile Court to Try Shooting Defendant
• Autos Killing 110 a Day Let's Resolve to Do
  Better
• Collegians are Turning to Vegetables

85
AMBIGUITY

• 2) BEGGING the QUESTION
• circular reasoning
• circulus in demonstrando or petitio principii
• avoidance, non-responsiveness
• restating the premise without answering the
  question begs another question or other questions
• circular reasoning turns the question around
  without answering it
• uses what is trying to be proved as part of the
  proof the proposition appears in the
  syllogism/proof

86
AMBIGUITY

• 2) BEGGING the QUESTION (contd)
• When is a fetus a person? When it is no longer a
  fetus. When the doctor says so. When it has the
  attributes of a person.
• Answers beg other questions When is it no
  longer a fetus? When does a doctor say so? What
  are the attributes of a person? When does a
  fetus acquire such attributes?
• Syllogism It is wrong to kill innocent human
  beings. Fetuses are innocent human beings. Thus,
  aborting fetuses is wrong.
• innocent ?
• fetushuman being?

87
AMBIGUITY

• EXAMPLES of BEGGING the QUESTION
• My mother is a good person because shes so
  moral.
• Homosexuals must not be allowed to hold
  government office. Hence any government official
  who is revealed to be a homosexual will lose his
  job. Therefore homosexuals will do anything to
  hide their secret, and will be open to blackmail.
  Therefore homosexuals cannot be allowed to hold
  government office.
• Petitio principii The Bible is the word of
  God. The word of God cannot be doubted, and the
  Bible states that the Bible is true. Therefore
  the Bible must be true.

88
AMBIGUITY

• 3) EQUIVOCATION
• quibble on the meaning of word/s
• a deliberate tactic to delay, distort, clutter,
  or avoid issue
• trivial distinctions euphemisms misuse of
  definitions
• obfuscates, obscures the real issue
• I didnt steal your money I merely borrowed
  it.
• The issue is not about if you stole or
  borrowed, but that you took the item without
  asking permission.

89
AMBIGUITY

• EXAMPLES of EQUIVOCATION
• Knock, knock! Who's there, in the other
  devil'sname? Faith, here's an equivocator, that
  couldswear in both the scales against either
  scale     who committed treason enough for
  God's sake,yet could not equivocate to heaven
  O, comein, equivocator. (from Macbeth 2.3.8-13)
• That depends on what your definition of is
  is.
• terrorists or freedom fighters, communist
  or Marxist, refugee or illegal immigrant

90
AMBIGUITY

• 4) LOADED LANGUAGE
• biased words
• leading questions/statements, the answer to which
  is misleading or damning
• readers should question users motives (ethos)
• they dont want to consider the issue theyve
  already made up their minds
• their questions are often statements
• sarcasm irony ambiguity (so avoid using
  either)

91
AMBIGUITY

• EXAMPLES of LOADED LANGUAGE
• Do I have to research any more junk on this
  stupid topic for this worthless class?
• Concerning the inexperienced Presidents hasty,
  subvert, and ill-considered appointment of such
  an incompetent and unproven judge, is this the
  type of underhanded, thoughtless behavior we can
  expect from this administration?
• Have you stopped beating your wife?

92
AMBIGUITY

• 5) FALSE ANALOGY
• false relationship, false comparison, false
• impression
• more differences between the 2 than similarities
• (despite few superficial similarities)
• dig more and find that not related
• collapse when examined critically (difficult to
  use)
• exaggerations
• key words is like

93
AMBIGUITY

• DESCRIPTIVE vs. EXPLANATORY
• DESCRIPTIVE metaphorical, more colorful than
  precise, remain dissimilar, short cuts, not
  enough to support your claim
• life is a bowl of cherries
• Malcolm X, criticizing the participation of
  whites in the 1962 march on Washington, DC Its
  like when youve got some coffee thats too
  black, which means that its too strong. What do
  you do? You integrate it with cream, you make it
  weak. But if you pour too much cream in it, you
  wont even know you ever had coffee.
• Claim integration of whites blacks in the
  march weakened the black movement for rights
  jobs.
• Support putting white cream into black coffee
  weakens the coffee.
• Warrant weakening coffee with cream is
  analogous to weakening the black rights movement
  by allowing white people to participate.
• Vivid descriptive, but not convincing. Too many
  dissimilarities. Strong and weak need to be
  defined. No facts, no proof, just racist opinion.

94
AMBIGUITY

• EXPLANATORY more than imagery offer facts,
  proof
• In a world of nuclear overkill and redundance,
  the United States and the Soviet Union are like
  two rivals locked in a small room in a duel to
  the death where one has 1,400 pistols and the
  other 1,200. The one with 1,400 has no advantage
  when one or both of the parties are likely to be
  killed or maimed with the first pistol shot.
• Claim In enlarging their nuclear arsenals, the
  US and the USSR are engaged in a duel that
  neither can win.
• Support A duelist in a locked room with 1,400
  pistols could probably not win against a duelist
  with 1,200 pistols.
• Warrant A pistol duel is analogous to the
  nuclear arms rivalry between the US and the USSR.
  (still some dissimilarities)

95
AMBIGUITY

• EXAMPLES of FALSE ANALOGY
• The Patriot Act turns our government into
  another Reich.
• Bush and Hitler
• 9/11 and Pearl Harbor
• Vietnam and Iraq 2003

96
IV. FAULTY REASONING
97
FAULTY REASONING

• The problem with these fallacies
• lies in the logic
• the reasoning process
• rather than the data.

98
FAULTY REASONING

• 1) FALSE DILEMMA
• either/or thinking
• HINT the words either/or are often used
• LIKE Oversimplification, Loaded Language
• assumes only 2 sides to an issue exist
• both sides may be unpleasant, but 2nd usually is
• BUT more than 2 options, causes, sides to an
  issue

99
FAULTY REASONING

• EXAMPLES of FALSE DILEMMA
• You either support Feminism or youre a sexist
  pig.
• Either man was created, as the Bible tells us,
  or he evolved from inanimate chemicals by pure
  random chance, as scientists tell us. The latter
  is incredibly unlikely, so...
• You are either for unilateral nuclear
  disarmament or for nuclear war.
• In a 1975 interview, the Shah of Iran was asked
  why he could not introduce into his authoritarian
  regime greater freedom for his subjects. He
  replied, Whats wrong with authority? Is anarchy
  better? So, its either authoritarianism or
  anarchy.

100
FAULTY REASONING

• 2) NON SEQUITUR
• it does not follow
• Big Leap in logic, faulty conclusion,
  unconnected, doesnt make sense
• irrelevant information (like ad populum)
• A B does not necessarily C
• Faulty INDUCTION
• too big of a leap from the Specific to the
  General

101
FAULTY REASONING

• EXAMPLES of NON SEQUITUR
• Since half a million copies were sold it was a
  best-seller for two decades, it must be a great
  book.
• We dont need books and libraries anymore
  because the Internet has so much information.
• Since Egyptians did so much excavation to
  construct the pyramids, they were well versed in
  paleontology.
• Since the President is away from the White House
  so often, the Vice President must run the
  country.
• Since e-mail is so popular, we might as well
  stop making envelopes, stamps, and paper.
• From the makers/producers/creators/director of
  the hit
• From the team that brought you the hit

102
FAULTY REASONING

• 3) RATIONALIZATION
• rationalize
• blame someone/thing else
• self-serving excuse
• flimsy justification
• its not my fault its yours
• We talk ourselves into something -- Do we ever
  rationalize something good?

103
FAULTY REASONING

• EXAMPLES of RATIONALIZATION
• I cant hand in my paper today because the dumb
  computer wouldnt print it. (blame scapegoat,
  like Scarecrow)
• You cant make an omelette without breaking a
  few shells. (blame virtue)
• Yeah, I knocked over the garbage can, but you
  shouldnt have put it in my way. (blame another)
• Its OK if I have another piece of cake Ill
  just go for a run tomorrow. (self-serving
  justification)

104
FAULTY REASONING

• EXAMPLES of RATIONALIZATION
• Its only this one time.
• OK, but this is the last time.
• Just one more.
• Its Spring Break.
• Im away at college.
• Im an adult now.
• No one will ever know.
• My parents will never know.
• Whos ever going to see those pictures?
• I needed the money.
• It doesnt hurt anybody.
• Its in the privacy of my own home.
• Im entitled
• age, class, race
• I worked hard all week or semester.
• Its my life!

• Everyone else is doing it. (like Tu Quoque)
• Its on sale.
• Ill just cram the night before.
• Ill go out tonight and just study all day
  tomorrow.
• Ill just.
• CHEATING excuses
• Everyones doing it.
• Look at the business world!
• The technology was made to help us cheat.
• If the teacher were smart enough to catch me
  cheating.
• The teacher grades on a curve, so I have to
  cheat.
• I have to because of Affirmative Action.
• I really need an A.
• Its not my major.

105
FAULTY REASONING

• EXAMPLE from Blues Brothers
• Jake Oh, please, dont kill us. Please, please
  dont
• kill us. You know I love you baby. I wouldnt
  leave
• ya. It wasnt my fault.
• Mystery Woman You miserable slug! You think you
  can talk your way out of this? You betrayed me.
• Jake No I didnt. Honest... I ran out of gas. I,
  I had a flat tire. I didnt have enough money for
  cab fare. My tux didnt come back from the
  cleaners. An old friend came in from out of town.
  Someone stole my car. There was an earthquake. A
  terrible flood. Locusts. IT WASNT MY FAULT, I
  SWEAR TO GOD!

106
FAULTY REASONING

• 4) REDUCTIO AD ABSURDUM
• reduce to absurdity
• use opponents reasoning against them
• extend their argument to its absurd conclusion
• often employed to ridicule opponent
• sarcasm, ridicule
• similar, in this respect, to Straw Man
• also, based on the fallacious assumption that
  more is better or that less is better

107
FAULTY REASONING

• EXAMPLES of REDUCTIO AD ABSURDUM
• If we allow a man to marry another man, then we
  might as well allow him to marry a dog or a
  sheep.
• If 2 are good, then 5 are better, but then all
  of them would be best.
• If 2 less is good, then 5 less would be better,
  but then getting rid of them all would be best.
• Since my physical therapist told me to do 3 sets
  of 10 with my dumbbells, I should be cleared to
  play sooner if I do 6 sets of 20 still, if I do
  12 sets of 40, Ill be reactivated much sooner.

108
FAULTY REASONING

• 5) SLIPPERY SLOPE
• next stepdanger/forbidden
• always ends badly (highway to hell)
• one thing must lead to another
• (1 drink/puff addiction)
• dangerous proposals
• too simplistic, ignores the similarities, ignores
  the complexity of life and institutions, ignores
  checks and balances

109
FAULTY REASONING

• SLIPPERY SLOPE vs. REDUCTIO AD ABSURDUM
• SS ends with something bad, but possible
• RAA ends with something absurd, impossible
• Arguments against opening a casino
• If we pass this referendum and allow this casino
  to open, then well be overrun by gambling
  addicts. (SS)
• one small steps, ends in something bad but
  possible
• If we pass this referendum and allow this casino
  to open, then well be overrun by zombies and
  demons. (RAA)
• ends with something absurd, impossible
• You want to open a casino in the area, so youre
  pro-gambling. Because youre in favor of
  gambling, you must also be in favor of child
  prostitution because thats what gambling addicts
  force their children into in order to feed their
  addiction.

110
FAULTY REASONING

• EXAMPLES of SLIPPERY SLOPE
• She kept her kid away from soda because one
  drink and hed be addicted to it for life.
• If we legalize marijuana, then more people would
  start to take crack and heroin, and wed have to
  legalize those too. Before long we'd have a
  nation full of drug-addicts on welfare.
  Therefore, we cannot legalize marijuana.
• Legalizing abortion will lead to murder of the
  elderly and the physically and mentally
  handicapped.
• If we ban handguns, whats next?! Rifles and
  other hunting weapons?!
• If we allow gays to marry, then the human race
  will become extinct.

111
extras
112
extras

• Argumentum ad antiquitatem (appeal to antiquity
  or tradition)
• something (behavior, practice, policy)
  right/acceptable because of tradition
• It's always been done that way.
• Every great civilization has believed in a
  higher power.
• Argumentum ad novitatem
• opposite of the Argumentum ad Antiquitatem
• something better or more correct simply because
  it is new, or newer than something else.
• Windows XP is better than Windows 2003 because
  WXP just came out."

113
extras

• Argumentum ad nauseam
• made to the point of disgust by repetition
• repetition to substitute for actual, real
  arguments, w/o substantiation, w/o justification
• Leading or loaded or complex question
• no right way to answer assumes something to be
  true by its construction
• Have you stopped beating your wife ?

114
extras
Appeals to Authority to Belief to Common Practice to Consequences of a Belief to Fear to Flattery to Pity to Ridicule to Spite to SEX!!! Biased Sample Burden of Proof Ad Hominem Tu Quoque Circumstantial Ad Hominem Composition Confusing Cause Effect Division Gambler's Fallacy Ignoring A Common Cause Middle Ground Misleading Vividness Poisoning the Well Questionable Cause Relativist Fallacy Special Pleading Spotlight Two Wrongs Make A Right lthttp//www.nizkor.org/features/fallacies/gt