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Flashcards in Chapter 3.1-3.4 Deck (35)
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Deductive argument

- if premise are true the conclusion is necessarily true
- goes from particular to general

1) arg based on math
2) arg by definition
3) categorical syllogism (all some or no)
4) hypothetical syllogism (if... Then)
5) disjunctive syllogism (either.. Or)


Affirming the consequent

P1: if p, then q
P2: q
C: p

- Invalid form of reasoning because conclusion is not true


Denying the antecedent

P1: if p, then q
P2: not p
C: not q




- is an error in reasoning
- "non sequitur" (it does not follow that)


Formal fallacies

- it is identified merely by examining the form or structure (deductive identifiable forms)


Informal fallacies

- can only be detected by examining the content of the argument


Fallacies of Relevance

- share the common characteristics that the arguments in which they occur have premises that are logically irrelevant to the conclusion

1) appeal to force
2) appeal to pity
3) appeal to the people (7 types)
4) argument against the person (3 types)
5) accident
6) straw man
7) missing the point
8) red herring


Appeal to force

- occurs whenever an argued poses a conclusion to another person and tells that person that some harm will come to him or her if she/he does not accept the conclusion


Appeal to pity

- occurs when an argued attempts to support a conclusion by merely evoking pity from the reader or listener


Appeal to the people

- uses people's desires to get the reader or listener to accept a conclusion

Subtypes of appeal to the people
2 approaches indirect and direct
1) appeal to fear
2) bandwagon argument
3) appeal to vanity
4) appeal to snobbery
5) appeal to tradition


Appeal to the people
- Direct approaches

1) occurs when an arguer addresses large groups of people and gets them excited into a mob mentality

2) appeal to fear- arguer trumps up a fear of something in the mind of the crowd and uses that fear as a premise for some conclusion


Appeal to people
- indirect approach

- arguer aims his or her appeal not at the crowd but at the individuals separately

1) bandwagon argument
- everyone believes such and such or does such and such therefore you should too
2) appeal to vanity
- linking the love, admiration or approval of the crowd with some famous figure who is loved, admired and approved of
3) appeal to snobbery
- the crowd that the arguer appeals to is a smaller group that is supposed to be superior in some way
4) appeal to tradition
- an arguer cites the fact that something has become a tradition as grounds for some conclusion


Argument against the person

- involves two argues, one advances a certain argument and the other redirects the argument not to the first persons argument but to the person himself

Three forms
1) ad hominem abusive
- second person responds to the first persons argument by verbally abusing the first person
2) ad hominem circumstantial
- second person attempts to discredit the opponents argument by alluding to certain circumstances that affect the opponent
3) Tu quoque (you too)
- second arguer attempts to make the first appear hypocritical or arguing in bad faith



- when a general rule is applied to a specific case that it was not intended to cover
- cited in premises and then wrongly applied to the conclusion


Straw Man

- when an arguer distorts an opponents argument for the purpose of more easily attacking it, demolishes the distorted argument and then concludes that the opponents real argument has been demolished


Missing the Point

- when the premises of an argument support one particular conclusion, but then a different conclusion is drawn


Red Herring

- arguer diverts the attention of the reader by changing the subject to a different but sometimes subtly related one


Fallacies of weak induction

- the connection between the premise and conclusion is not strong enough to support the conclusion

1) appeal to unqualified authority
2) appeal to ignorance
3) hasty generalization
4) false cause (4 types)
5) slippery slope
6) weak analogy


Appeal to Unqualified Authority

- when the cited authority or witness lacks credibility


Appeal to Ignorance

- premise states that nothing has been proved one way or the other about something, and the conclusion then makes a definite assertion about that thing


Hasty Generalization

- an argument that draws a conclusion about all members of a group based on a select few (OPPOSITE of this)


False Cause

- occurs whenever the link between the premises and conclusion depends on some imagined casual connection that probably doesn't exist

1) post hoc ergo propter hoc (after this therefore on account of this)
- just bc one event precedes the other, the first event causes the second
2) non causa pro causa (not the cause for the cause)
- what is taken to be the cause of something is not really the cause at all
3) oversimplified cause
- a multitude of causes is responsible for a certain effect but the arguer selects just one of these causes and represents it as if it were the sole cause
4) gamblers fallacy
- conclusion of an argument depends on the supposition that independent events in a game of chance are casually related


Slippery slope

- when the conclusion of an argument rests on the alleged chain reaction and there is not sufficient reason to think the chain reaction will actually take place


Weak analogy

- when the analogy is not strong enough to support the conclusion drawn


Fallacies of presumption

- premises presume what they purport to prove

1) begging the question
2) complex question
3) false dichotomy
4) suppressed evidence


Fallacies of ambiguity

- some form of ambiguity in either premise or conclusion

1) equivocation
2) amphiboly


Fallacies of illicit transference

- incorrect transference of an attribute from the parts of something onto the whole, or from the whole onto the parts

1) composition
2) division


Begging the question

- arguer creates the illusion that inadequate premises provide adequate support for the conclusion by leaving out a possible false (shaky) key premise, by restating a possibly false premise as the conclusion, or by reasoning in a circle


Complex question

- when two or more questions are asked in the guise of a single question and a single answer is then given to both of them


False dichotomy

- when a disjunctive (either.. Or) premise presents two unlikely alternatives as if they were the only ones available, then the arguer gets rid of the undesirable one leaving just the desirable option