Reasoning & Problem Solving Lecture 5b More Fallacies By David Kelsey

Ad Hominem To commit this fallacy is to think that some consideration about a person refutes the claims that he or she makes. Confusing the person and the claim: –Criticizing the person not the claim itself

Ad Hominem again A personal attack ad hominem: –claiming that because someone has certain negative features it follows that a claim she makes is false. –Examples Inconsistency ad hominem: –to hold that what someone says is false because it is inconsistent with something else she has said or done. –Examples

Circumstantial & Positive ad hominem Circumstantial ad hominem: –holding that because a person’s circumstances are a certain way it follows that some claim she makes is false. –Priest example Positive ad hominem: –holding that the claim a person makes follows from some positive consideration about the person. –Einstein example

Poisoning the Well To poison the well –an in advance ad hominem. –For example, Rumors…

Genetic Fallacy When one tries to refute a claim based on its origin or history she has committed the genetic fallacy. –Belief in God’s existence –Genetic fallacy vs. Circumstantial ad Hominem

Straw Man Straw man fallacy: –trying to refute a claim or argument by distorting it or oversimplifying it or misrepresenting it in such a way that it can be easily refuted. –Reconfiguring a claim –Knocking down a straw man –Knocking down a straw man is easy business but knocking down a good argument is not.

False Dilemma False dilemma –limits considerations to a choice between only two alternatives although other reasonable alternatives are available. –The form of a false dilemma: –Using a false dilemma for the purpose of deception –Example: Prayer in public schools

Perfectionist fallacy –Rejecting a policy or claim because it isn’t perfect. –A kind of false dilemma –Example: Instant replay

Line Drawing Fallacy The Line-Drawing fallacy –insisting that a conceptual line must be drawn at a particular point when drawing such a line isn’t necessary. –Examples: Rich Bald Excessive force –Line drawing and Vagueness

Slippery Slope Slippery Slope: –Claiming that if we let some thing X occur it follows that something else Y will occur, yet there is no reason to think that if X occurs so must Y. –Causation and slippery slope arguments –Example: Hand gun laws

Misplacing the Burden of Proof Misplacing the burden of proof: –Misplacing the burden of proof on the wrong side of an issue. –The 2 sides of an issue –Example: Should we go to war with Iraq?

The burden of proof To say the burden of proof rests on a claim: –This just means that if one is to hold this position, then she must support it with argumentation. –Example: Iraq again –Temporal Priority

Where does the burden lie? Placing the burden –Plausibility: The burden ought to be placed on whichever side of an issue is less plausible. Example: –Affirmative: The burden, in general, ought to be placed on the affirmative side of an issue. Example:

The burden of proof #3 Special Circumstances: –Under special circumstances the burden of proof is placed on a particular side of an issue. –The court: The defendant is always innocent until proven guilty

Appeal to ignorance –claiming that we should believe that some claim is true because no one has proved it false. –Example: Ghosts exist

Begging the Question One begs the question when one of the premises of her argument assumes the truth of the conclusion. Examples: –Abortion –An argument for God’s existence Circular reasoning