PHIL
106: Critical Thinking
LARKIN
Southern
Illinois University Edwardsville
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.
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.
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.
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.
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.
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