PHIL 106: Critical Thinking

LARKIN

Southern Illinois University Edwardsville

 

Fallacies

 

I.                     Definitions

A.      Fallacy =df A common pattern of bad but seductive reasoning.

1.        The reasoning is bad (i.e., fallacious) because the premises do not provide logical support for the conclusion.

2.        The reasoning is seductive because we are easily misled into thinking that the conclusion does provide logical support for the conclusion.

 

B.       Fallacies of Relevance

1.        These arguments are fallacious because the truth of the premises is not even logically relevant to the truth of the conclusion.

2.        They are seductive because the premises are psychologically relevant to the conclusion.

 

C.       Fallacies of Presumption

D.      Fallacies f Ambiguity

 

 

II.                   Fallacies of Relevance

A.      Ad Hominen [to the person]

1.        Fallacious: One attacks a position or argument by attacking the person who holds the position or gives the argument, rather than supplying reasons against the position or finding some flaw in the argument.

2.        Seductive: Because it is psychologically easy to confuse the message and the messenger.

3.        EX:  Don’t buy Senator X’s argument against gun control legislation, because Senator X is a card-carrying member of the National Rifle Association.

 

B.      Appeal to Force

1.        Fallacious: One tries to get someone to accept a conclusion not by providing reasons in support of the conclusion but by threatening the person with some kind of harm.  An appeal is made not to one’s reason but to one’s natural instincts/fear.

2.        Seductive: Because we have a natural instinct to do what it takes to avoid harm, and we confuse pragmatic with rational reasons.

3.        EX:  Agree that the Orioles will win the World Series or I’ll tear up your treasured Mickey Mantle rookie card.

 

C.      Appeal to Pity

1.        Fallacious: Because it tries to persuade someone to believe something X about a person because that person deserves our pity, when the reason the person deserves pity is not even relevant to whether X is true.

2.        Seductive: Because we have natural sympathy for other people, and want to do whatever we can for a person that we feel sorry for.

3.        EX:  We should elect player X to the all star team (even though X is batting less than .250) because X is dying of cancer.

 

D.      Ad Populum (to the people)

1.        Fallacious: Attempts to persuade you to believe something just because everyone else believes it.

2.        Seductive:  We all have natural insecurities and want to fit in and be like other people.

3.        EX:  Television commercials that claim you should buy their product because it is the best selling (i.e., most popular) in the country.

 

E.       Appeal to Inappropriate Authority

1.        Fallacious:  Argues that something is true on the basis that someone said it is true, even though that person is no expert in the field or anything of the sort.

2.        Seductive:  We easily think that an expert in some area is an expert in all/other areas.

3.        EX:  Einstein (an expert in Physics/Math) thought there was a God, so God must exist. 

 

F.       Argument from Ignorance

1.        Fallacious:  Claims that something is true/false simply because it has not been proven otherwise.

2.        Seductive:  We overestimate our capacities and tend to think that if we cannot prove it or show that it is true, then it must not be true.

3.        EX:  Since there has never been a convincing proof of the existence of God, it follows that God does not exist.

 

G.      Idenitifcations: Identify the fallacies of relevance committed in the following passages.

1.        There can’t be anything wrong with stealing office supplies, since nearly everyone does it.

2.        The position open in accounting should go to Frank.  His wife needs an operation to save her eyesight.

3.        Opponents of the Gestapo’s policies have, let us say, failed to flourish.  So I am sure that you will see the wisdom of their policies.

4.        The claims of mediums and clairvoyants have never been completely refuted.  Therefore, their claims are reasonable to believe.

5.        RJ Palmer, D.D.S., one of this community’s leading dental practitioners says that the whole theory of evolution is probably mistaken.  Thus Creationism is probably true.

6.        Most students are in favor of beer on campus, so beer should be served at student dining facilities.

7.        If you are wondering whether to get me a Christmas gist, keep in mind that I have not decided whether to offer you a promotion yet.

8.        Publishing magnate Steve Forbes has argued at length that the fairest kind of income tax is a flat rate.  But Forbes is a billionaire who stands to save millions by a flat tax.  So we should reject Forbes’ arguments.

9.        There must be something to ESP.  Three famous physicists—Lodge, Jeans, and Eddington—have all taken it seriously.

10.     Evolution is nothing more than a ‘theory’ and has not been proven.  Therefore, we should reject it in favor of Creationism.

 

III.                 Fallacies of Presumption

IV.                 Fallacies of Ambiguity