Presentation on theme: "Logical Fallacies. Definition & Facts Defects that weaken arguments weaken arguments Common in politics and politics and advertisements advertisements."— Presentation transcript:
Definition & Facts Defects that weaken arguments weaken arguments Common in politics and politics and advertisements advertisements Often very persuasive persuasive
Don’t weaken your argument with faulty reasoning!
When you attempt to employ logic to support claims in your papers, your reasoning is sometimes weakened because you are presenting fallacious arguments. It is important for you to be able to identify and eliminate fallacies in your writing.
Check this out! This fallacy is very common in advertising, as in this simple example.
Unchanged Since 1899 (Reader's Digest, March, 1999, p. 15)
Hershey’s Advertisement Appeal to Tradition Appeal to Tradition Any argument that defends a behavior or choice by pointing out that the behavior or choice is a longstanding practice. Unfortunately, many foolish and destructive behaviors are also very traditional, such as slavery, forced prostitution, and punishing children by hitting them with belts. belts.
What the heck does this mean? bandwagon
bandwagon: logical fallacy in which the writer uses the argument that because everyone believes in something, it must be true.
Example “I’m going to the party because all my friends are going!”
What the heck does this mean? begging the question
begging the question: logical fallacy in which the writer presents an assertion that simply restates the point just made
Example "Exposure to asbestos is carcinogenic because it causes cancer.”
What the heck does this mean? ad hominem
ad hominem: logical fallacy in which the writer attacks the person who presents the issue rather than deal logically with the issue itself.
Example "Ignore what Professor Doe says about the origins of the Old Testament. I happen to know that Doe is an atheist."
What the heck does this mean? either-or fallacy
either-or fallacy: logical fallacy in which the writer states that only two alternatives exist when in fact there are more than two.
Example “Caldwell Hall is in bad shape. Either we tear it down and put up a new building, or we continue to risk students’ safety. Obviously we should not risk anyone’s safety, so we must tear the building down."
What the heck does this mean? red herring
red herring: logical fallacy in which the writer dodges the real issue by drawing attention to an irrelevant issue (ignoring the question).
Example Real Example: "No, no, he's a friend of mine. He's not a moron at all -- he's a friend. I had a good time with him today." Canadian Prime Minister Jean Chretien, responding to reports that his chief spokesman had called President George W. Bush a moron. (Newsweek, 2 Dec. 2002) Analysis: Perhaps it's true that Bush is his friend. Perhaps it's true that they had a good time together. What has that information got to do with answering the charge that Bush is a moron? Chretien is changing the subject instead of talking about Bush's intelligence.