Logical Fallacies

Ad Hominem

“against the man”, attacking the arguer rather than the argument or issue

Ad Populum

“to the crowd”, the misconception that because a great number of people do something, it is therefore correct. the parents of sylvia’s friends alow their daughters to stay out until 2 a.m., therefore Sylvia’s parents should let Sylvia stay out until 2:00 a.m. as well

Appeal to Authority

Person A is (or claims to be) an authority on subject S. Person A makes claim C about subject S. Therefore, C is true

Appeal to Belief

Most people believe that X is true, therefore X is true

Appeal to Emotion

when the arguer manipulates emotions in order to get people to accept a claim as being true

Appeal to Popularity

“the new UltraSkinny diet will make you feel great. no longer be troubled by your weight. enjoy the admiring stares of the opposite sex. revel in your new freedom from fat.”

Appeal to Fear

you must believe that God exists. after all, if you don’t accept the existence of God, you’ll face the horrors of hell

Appeal to Flattery

might I say that this is the best class i’ve ever taken. by the way, about those two points I need to get an A…

Appeal to Novelty

our company has to eb on the cutting edge. that means new ideas and new techniques have to be used. the GK method is new, so it will do better than the old method

Appeal to Pity

i’m positive that my work will meet your requirements. i really need the job since my grandmother is very sick

Appeal to Ridicule

support the ERA? sure, when the women start paying for the drinks!

Appeal to Spite

you can’t be serious about nominating John for president. remember what he pulled last year?

Appeal to Tradition

i believe in God. people have believed in God for generations, so God must exist

Bandwagon

threat of rejection from one’s peers replaces evidence in an argument. “i realize prejudice is wrong, but we don’t allow African Americans or Women in our group. you understand"

Begging the Question

taking for granted something that needs proving. ‘free all political prisoners’

Biased Sample

drawing a conclusion about a population based ona sample that is biased or prejudiced. in determining the population’s stance on gun control, polling only NRA members would be a biased sample

Circular Reasoning

trying to prove one idea with another idea that is too similar to the first. “A writer is a person who writers”

Confusing Cause & Effect

A and B regularly occur together. Therefore A is the cause of B

Hasty Generalization

drawing a general and premature conclusion on the basis of only one or two cases. “all dogs should be muzzled because a golden retriever disturbed the peace in the park”

Middle Ground

Position A and B are too extreme. C rests in between A and B. therefore C is the correct one

Motivational Appeal

an attempt to reach an audience by recognizing their needs and values and how these contribute to their decision making

Non Sequitur

“it does not follow” an inference or conclusion that does not follow established evidence or premises. “he’s the most popular, therefore he should be president”

Poisoning the Well

unfavorable information about person A is presented (true or false). therefore, any claims made by person A will be false

Post Hoc

“after this, therefore because of this” assuming that an incident that precedes another is the cause of the second. “Andy worked on his science paper longer than his English paper, therefore he felt he should earn an A”

Propaganda

writing or images that seek to persuade through emotional appeal rather than logical proof, written or visual texts that describe or depict using highly connotative words or images without justification

Red Herring (Wild Goose Chase)

diverting attention from the issue by introducing a new point

Reductio ad Absurdum

“to reduce to the absurd” it reduces an argument to an either/or choice. “the possession of firearms should be completely banned or completely legal”

Slippery Slope

predicting without justification that one step in a process will lead unavoidably to a second, generally undesirable step

Straw Man

disputing a view similar to, but not the same as, that of the arguer’s opponent

Two Wrongs Make a Right

Bill has borrowed Jane’s pen, but found he didn’t return it. he tells himself that it is okay to keep it, since she would have done the same