Flaw Flashcards
Error/Flaw Types
1) Uncertain Use of a Term or Concept
2) Ad Hominem - flawed argument attacks the person (or source) instead of the argument they advance
3) Circular Reasoning - the author assumes as true what is supposed to be proved
4) Errors of Conditional Reasoning
5) Mistaken Cause and Effect (temporal relationship, correlation, alternate cause, reversal)
6) Straw Man - when an author attempts to attack an opponent’s position by ignoring the actual statements made by the opposing speaker and instead distorts and refashions the argument, making it weaker in the process
7) Lack of Relevant Evidence for the Conclusion
8) Internal Contradiction
9) Appeal Fallacies
a. Authority
b. Popular Opinion/Appeal to Numbers
c. Emotion
- Survey Errors
- Exceptional Case/Overgeneralization
- Errors of Composition and Division
- False Analogy
- False Dilemma
- Errors in the Use of Evidence
- Time Shift Errors
Ad Hominem
Source Argument Flaw - Also known as an ad hominem, this type of flawed argument attacks the person
(or source) instead of the argument they advance.
A source argument can take different forms, including the following:
- Focusing on the motives of the source.
- Focusing on the actions of the source (as in the below example).
“The anti-smoking views expressed by Senator Smith should be ignored. After all, Smith himself is a smoker!”
What is another name for a Source Argument Flaw
Ad Hominem
Source Argument Flaw - Also known as an ad hominem, this type of flawed argument attacks the person
(or source) instead of the argument they advance.
A source argument can take different forms, including the following:
- Focusing on the motives of the source.
- Focusing on the actions of the source (as in the below example).
“The anti-smoking views expressed by Senator Smith should be ignored. After all, Smith himself is a smoker!”
“it assumes what it seeks to establish”
Circular Reasoning
In circular reasoning the author assumes as true what is supposed to be proved
“presupposes the truth of what it sets out to prove”
Circular Reasoning
In circular reasoning the author assumes as true what is supposed to be proved
“it offers, in place of support for its conclusion, a mere restatement of
that conclusion”
Circular Reasoning
In circular reasoning the author assumes as true what is supposed to be proved
“it takes for granted the very claim that it sets out to establish”
Circular Reasoning
In circular reasoning the author assumes as true what is supposed to be proved
What is a synonym for Sufficient
in the same way that Required is a synonym for Necessary
Assured
It is interesting to note the frequency with which the words “sufficient” (or its
synonym “assured”) or “necessary” (or its synonym “required”) are used when
analyzing the answer choices used to describe conditional reasoning.
“taking the nonexistence of something as evidence that a necessary precondition for that thing also did not exist”
“taking the nonexistence of something as evidence that a necessary precondition for that thing also did not exist”
(Mistaken Negation)
“mistakes being sufficient to justify punishment for being required to justify it”
“mistakes being sufficient to justify punishment for being required to justify it”
(Mistaken Reversal)
Mistaken Cause and Effect
- Assuming a causal relationship on the basis of the sequence of events.
“mistakes the observation that one thing happens after another for proof that the second thing is the result of the first”
“mistakes a temporal relationship for a causal relationship” - Assuming a causal relationship when only a correlation exists.
“confusing the coincidence of two events with a causal relation between the two”
“assumes a causal relationship where only a correlation has been indicated” - Failure to consider an alternate cause for the effect, or an alternate cause for both the cause and the effect.
“fails to exclude an alternative explanation for the observed effect”
“overlooks the possibility that the same thing may causally contribute both to education and to good health” - Failure to consider that the events may be reversed.
“the author mistakes an effect for a cause”
If you identify a stimulus with causal reasoning and are asked a Flaw question, quickly…?
scan the answers for one that contains “cause” or “effect”
Straw Man
This error occurs when an author attempts to attack an opponent’s position by ignoring the actual statements made by the opposing speaker and instead distorts and refashions the argument, making it weaker in the process. In figurative terms, a “straw” argument is built up which is then easier for the author to knock down.
“refutes a distorted version of an opposing position”
“misdescribing the student representative’s position, thereby making it easier to challenge”
“portrays opponents’ views as more extreme than they really are”
“distorts the proposal advocated by opponents”
Appeal to Authority
An Appeal to Authority uses the opinion of an authority in an attempt to persuade the reader. The flaw in this form of reasoning is that the authority may not have relevant knowledge or all the information regarding a situation, or there may a difference of opinion among experts as to what is true in the case
“the judgement of experts is applied to a matter in which their expertise is irrelevant”
“the argument inappropriately appeals to the authority of the mayor”
“it relies on the judgment of experts in a matter to which their expertise is irrelevant”
“accepts a claim on mere authority, without requiring sufficient justification”
Appeal to Popular Opinion/Appeal to Numbers
This error states that a position is true because the majority believes it to be true.
“A recent poll states that 75% of Americans believe that
Microsoft is a monopoly. Antitrust law states that monopolies have a deleterious effect on the marketplace (with the exception of utilities), and therefore Microsoft should be controlled or broken into smaller pieces.”
The author uses the results of a poll that indicate many people think Microsoft is a monopoly to conclude that Microsoft is in fact a monopoly
“it treats popular opinion as if it constituted conclusive evidence for a claim”
“attempts to discredit legislation by appealing to public
sentiment”
“a claim is inferred to be false merely because a majority of people believe it to be false”
“the argument, instead of providing adequate reasons in support of its conclusion, makes an appeal to popular opinion”
Appeal to Emotion
An Appeal to Emotion occurs when emotions or emotionally-charged language is used in an attempt to persuade the reader.
Here is an example:
“Officer, please do not give me a ticket for speeding. In the last month I’ve been fired from my job, kicked out of my apartment, and my car broke down. I don’t deserve this!
“attempts to persuade by making an emotional appeal”
“uses emotive language in labeling the proposals”
“the argument appeals to emotion rather than reason”
Survey Errors
The makers of the LSAT believe that surveys, when conducted properly, produce reliable results. However, surveys can be invalidated when either of the following three scenarios arise:
- The survey uses a biased sample.
- The survey questions are improperly constructed.
- Respondents to the survey give inaccurate responses
Exceptional Case/Overgeneralization
This error takes a small number of instances and treats those instances as if they support a broad, sweeping conclusion. Here is an example:
“Two of my friends were shortchanged at that store. Therefore, everyone gets shortchanged at that store. ”
This answer appears most frequently as an incorrect answer in Flaw questions, but as with any of the errors described in this chapter, occasionally it appears as
a correct answer.
“supports a universal claim on the basis of a single example”
“The argument generalizes from too small a sample of cases”
“Too general a conclusion is made about investing on the basis of a single experiment”
“bases a general claim on a few exceptional instances”
Errors of Composition and Division
Composition and division errors involve judgments made about groups and parts of a group.
An error of composition occurs when the author attributes a characteristic of part of the group to the group as a whole or to each member of the group
“Every party I attend is fun and exciting. Therefore, my life is fun and exciting.”
An error of division occurs when the author attributes a characteristic of the whole (or each member of the whole) to a part of the group. Here is an example:
“The United States is the wealthiest country in the world. Thus, every American is wealthy.”
Error of Composition
An error of composition occurs when the author attributes a characteristic of part of the group to the group as a whole or to each member of the group
“Every party I attend is fun and exciting. Therefore, my life is fun and exciting.”
Here are examples of how this error of reasoning is described in LSAT answer
choices:
“assuming that because something is true of each of the parts of a whole it is true of the whole itself”
“improperly infers that each and every scientist has a certain characteristic from the premise that most scientists have that characteristic”
“takes the view of one lawyer to represent the views of all lawyers”
Error of Division
An error of division occurs when the author attributes a characteristic of the whole (or each member of the whole) to a part of the group. Here is an example:
“The United States is the wealthiest country in the world. Thus, every American is wealthy.”
Here is an example of how this error of reasoning is described in LSAT answer choices:
“presumes, without providing justification, that what is true of a whole must also be true of its constituent parts”
when the author attributes a characteristic of the whole (or each member of the whole) to a part of the group.
An error of division occurs when the author attributes a characteristic of the whole (or each member of the whole) to a part of the group. Here is an example:
“The United States is the wealthiest country in the world. Thus, every American is wealthy.”
Here is an example of how this error of reasoning is described in LSAT answer choices:
“presumes, without providing justification, that what is true of a whole must also be true of its constituent parts”
when the author attributes a characteristic of part of the group to the group as a whole or to each member of the group
An error of composition occurs when the author attributes a characteristic of part of the group to the group as a whole or to each member of the group
“Every party I attend is fun and exciting. Therefore, my life is fun and exciting.”
Here are examples of how this error of reasoning is described in LSAT answer
choices:
“assuming that because something is true of each of the parts of a whole it is true of the whole itself”
“improperly infers that each and every scientist has a certain characteristic from the premise that most scientists have that characteristic”
“takes the view of one lawyer to represent the views of all lawyers”
Fallacy of Negative Proof
The author argues that since something has never been proven false, it must be true. Or, if something cannot be proven true, it must be false. This is a type of false consequences argument, since it assumes that all things must be proven true or false.
