Logical fallacies

OrSeriously… what were you thinking??

First, what’s a fallacy?Well, according to dictionary.com, a fallacy is:1. a deceptive, misleading, or false notion, belief,

etc.: That the world is flat was at one time a popular fallacy.

2. a misleading or unsound argument. 3. deceptive, misleading, or false nature;

erroneousness. 4. Logic. any of various types of erroneous reasoning

that render arguments logically unsound.

Okay, great… now put it in your own words in your notes.

So what’s a logical fallacy then?Going back to dictionary.com, a logical fallacy

is:

a fallacy in logical argumentation

Umm. Yeah. Put that in your own words, too.

Are there different types of logical fallacies?Oh my yes… here are a few of them:

Ad HominemBandwagonEither/Or (also called False Dilemma)Appeal to AuthorityCherry Picking the EvidenceGuilt (or Popularity) by Association

Ad Hominem? Isn’t that a song by the Muppets?

No no no! (Bonus points if you get the allusion, though!)

Ad hominem actually means 1. appealing to one's

prejudices, emotions, or special interests rather than to one's intellect or reason.

2. attacking an opponent's character rather than answering his argument.

Put this in your own words on your worksheet.

BandwagonOh cool! My parents have

one of those!Umm… no. In rhetoric, bandwagon

means: 1. a party, cause, movement,

etc., that by its mass appeal or strength readily attracts many followers: After it became apparent that the incumbent would win, everyone decided to jump on the bandwagon.

2. a fallacy in which a threat of rejection by one's peers (or peer pressure) is substituted for evidence in an “argument.”

Put this in your own words on your sheet.

Either/or (also called false dichotomy or false dilemma)

This one’s pretty straightforward. An either/or fallacy occurs when a speaker makes a claim that presents an artificial range of choices, usually suggesting that there are only two choices possible, when three or more really exist.  Those who use an either/or fallacy try to force their audience to accept a conclusion by presenting only two possible options, one of which is clearly more desirable.

Put this in your own words on your sheet.

Either you thought Avatar was the best movie ever, or you’re some sort of brain dead zombie.

Appeal to authority (also called Questionable Authority, Inappropriate Authority) This fallacy is

committed when the person in question is not a legitimate authority on the subject.

Put this in your own words.

There's comes a time in every father's life when he blows up his daughter's room.

Cherry picking (the evidence)The act of

pointing at individual cases or data that seem to confirm a particular position, while ignoring a significant portion of related cases or data that may contradict that position.

Put this in your own words.

Guilt by associationA fallacy in which a

person rejects a claim simply because it is pointed out that people she dislikes accept the claim.

The opposite can also be true: accepting a claim simply because the person making the claim is liked.

Put this in your own words on your sheet.

Is that it? By no means! In fact, your teacher has a nifty handout from the Undergraduate Writing Center at the University of Texas at Austin that organizes logical fallacies into the three rhetorical appeals (pathos, ethos, logos).

Live long and prosper by avoiding these fallacies in thinking!