Transcript Document

When Claims Go Wrong
Recognizing & Avoiding Logical Fallacies
Kim Miller Davis
Academic Essay Writing Process:
Step 1: Writer intakes information
Step 2: Writer analyzes information to formulate conclusion
Step 3: Writer develops plan to communicate conclusion
The plan is centered around proving the writer’s conclusion
which is called the Major Claim (aka Thesis).
The Thesis is proven through 3 Supporting Claims (aka Arguments).
First Step of Successful Communication:
Developing Logical Claims
Logical Claims
Allow the readers to easy follow the argument as it progresses
Claims Without Logic
Stop the Reader from going anywhere
The writer’s conclusion might be valid, but the
road to get there is broken
These errors in reasoning are called
Logical Fallacies
They tend to occur for three major reasons:
• False or weak premises
• Irrelevance
• Ambiguity
The Most Common Fallacies
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Ad Hominem
Bandwagon
Begging the Question or Circular Reasoning
Either/Or Reasoning
Weak Analogy
Post Hoc Ergo Propter Hoc
Hasty Generalization & Proof by Example
Slippery Slope
Dubious or False Authority
Non-Sequitur
Ad Hominem
Attacking the character of the arguer rather than the argument
http://www.youtube.com/watch?v=Ncw-acVB368
Bandwagon
Suggesting that a person should agree to something because it is
popular
http://www.youtube.com/watch?v=gQPN3UKQM-U
Begging the Question
Using Circular Reasoning to prove a conclusion
http://www.youtube.com/watch?v=8CVbku6nxhU
Either/Or Reasoning
Presenting someone with a limited choice, when other choices are
possible.
http://www.youtube.com/watch?v=3sfNROmn7bc
Weak Analogy
Making an improper comparison between two things that share a
common feature
Post Hoc Reasoning
Arguing that one event caused another when they are unrelated
http://www.youtube.com/watch?v=EJ1a0ymGCKA
Hasty Generalization
Using a part to make an inaccurate claim about a whole
http://www.youtube.com/watch?v=M2gvY2wqI7M
Romney makes a hasty generalization about
people who do not pay income tax.
In reality, that 47% includes:
• Elderly and People living on Social Security
• People making less than $20,000/year
• Active Duty Military & Retired Military
• People living solely on pension plans
• The Wealthy who make their living off of Capital Gains taxes
• Young People who are working hourly jobs
• College Students
Proof by Example
• Purporting a claim as “truth” through the use of minimal examples
“A lot of people on welfare are lazy. There is the one woman who
comes into H.E.B. with a cell phone, a BMW, and her nails done; yet she
buys her food with food stamps.”
“Illegal immigrants are damaging this country with crimes. Several men
who crossed the border in Nogales last week are known rapists.”
Slippery Slope
Suggesting that one event will automatically lead to a chain of other
events
False or Dubious Authority
Defending a claim with a biased or untrustworthy source
Non Sequitur
Stating a conclusion that doesn’t follow from the premises
http://www.youtube.com/watch?v=ErRHJlE4PGI