Flaws Flashcards
- “Cites irrelevant data”
- “Draws a conclusion that is not warranted by the evidence provided”
- “Uses inapplicable information to draw a conclusion”
- “Fails to give any reason for the judgement it reaches”
Errors in the use of evidence - Lack of relevant evidence for the conclusion`
- “Inconsistent claims”
- “irreconcilable presuppositions”
- “Conflicting premises”
Internal contradiction
takes an exceptional case or a small number of instances to make a general rule
Overgeneralization
- Lack of evidence is used to disprove a conclusion
- Lack of evidence against a position is used as proof that the conclusion is true
- Some evidence weakening a position is used to claim that the position is false
- Some evidence for a position is used to claim the position is true
Errors in assessing the force of evidence
Source argument (aka ad hominem)
- on the LSAT, it is never legit to attack the person instead of the argument, only the argument matters, so dismissing an argument on the basis of the source, whether they are attacking the source’s motives or actions etc. is a flaw
- “Assumes what it is attempting to demonstrate”
- “Presupposes what it sets out to prove”
- “Assumes the conclusion is true in stating the premises”
Circular reasoning - the author using the claim paraphrased as its own warrant
Mistaking sufficient and necessary conditions
Errors of conditional reasoning - the more tricky of these questions describe the errors in logical terms
“Taking the absence of an occurrence as evidence that a necessary condition for that occurrence also did not take place”
Mistaken negation
“Mistakes being sufficient to achieve a particular outcome as being required to achieve it”
Mistaken reversal
ignores the real argument made by the opponent and mischaracterizes it as an argument
Straw Man - ignores the real argument made by the opponent and mischaracterizes it as an argument (made of STRAW so to speak ) which is easier to defeat
“The argument appeals to emotion rather than reason”
appeal fallacy - Appeal to emotion - emotions or emotionally charged language
appeal fallacies
- Appeal to authority - citing the opinion of an inapplicable expert
- Appeal to popular opinions/numbers - saying something is true because a lot of people think it is
Appeal to emotion - emotions or emotionally charged language
Survey errors
- Biased sample
- Inappropriate sample
- Improperly constructed questions
- A survey where respondents are unlikely to give truthful responses (Qs about weight or money)
things true of members of a group are not necessarily true of the group as a whole and vice versa
Errors of composition and division
- “Depending on the ambiguous use of a key term”
- “It confuses two different meanings of the word X”
- “Equivocates with respect to a central concept”
Uncertain use of a term or concept (most common wrong answer choice given) - it’s only correct when the stimulus clearly uses the same word in two diff ways
compares something to something too dissimilar for the comparison to make sense
False analogy
acts as though there are only two possible outcomes/courses of action when that is not in fact the case
“Fails to consider…”
False dilemma
“Fails to consider…”
- “Treats a claim about the current state of affairs as if it were a claim about what has been the case for an extended period”
- “Draws an unwarranted inferences from what has been true in the past to what will be true in the future”
Time shift errors - just because something was true in a given time doesn’t mean it will continue to be true
assuming that knowledge about a quality something possesses relative to something else means more than it does (he has more money than me, so he is rich)
Relativity flaw
we’ve already invested $100m so we need to invest more or we will lose the investment!!
Sunk costs/concorde fallacy
- Making incorrect assumptions about numbers from percentages or vice versa
- Relativity mistakes
Numbers and percentage errors
“fails to address a highly plausible alternative explanation for all instances of the observed phenomenon”
false dilemma
acts as though there are only two possible outcomes/courses of action when that is not in fact the case
“Fails to consider…”
It overlooks the possibility that even if a disease is one of the most common in a nation, most people in that nation are not in significant danger of developing that disease.
relativity flaw
treats an occurrence that will ensure a certain outcome as something that is required for that outcome
The argument confuses a sufficient condition in the first premise for a necessary condition.
The argument confuses a sufficient condition in the first premise for a necessary condition.
mistaken reversal
rejects a claim merely on the grounds that its proponent holds another view inconsistent with it
source flaw - Just because someone might seem to be a hypocrite doesn’t mean that one of their opinions is wrong.
CORRECT takes for granted that something that has not been proven to be true is for that reason shown to be false
evidence flaw
