Logical Reasoning Bible
解 题 思 路 整 理
IPrimary Objectives:
1.Determine whether the stimulus contains an argument or if it is only a set of
factual statements;
2.If the stimulus contains an argument, identify the conclusion of the argument; If
the stimulus contains a fact set, examine each fact;
3.If the stimulus contains an argument, determine whether the argument is strong or
weak;
4.Read closely and know precisely what the author said. Do not generalize;
5.Carefully read and identify the question stem; Do not assume that certain words
are automatically associated with certain question types;
6.Prephrase; After reading the question stem, take a moment to mentally formulate
your answers to the question stem;
7.Always read each of the five answers;
8.Separate the answer choice into contenders and losers; After completing this
process, review the contenders and decide which is the correct one;
9.If all 5 answers appear to be losers, return to the stimulus and reevaluate the
argument.
IIBasics of Logical Reasoning
Premise IndicatorsCounter-Premise IndicatorsConclusion Indicatorsbecause, since, for, for But, yet however, on the thus, therefore, hence,
example, for the reason that, other hand, admittedly, in consequently, as a result, so,
in that, given that, as contrast, although, even accordingly, clearly, must
indicated by, due to, owing though, still, whereas, in be that, shows that,
to, this can be seen from, spite of, despite, after allconclude that, follows that,
we know this by, for this reason,
furthermore, moreover,
besides, in addition, what’s
more, after all
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Quantity IndicatorsProbability Indicators
all, every, most, many, some, several, few, Must, will, always, not always, probably, sole, only, not all, nonelikely, would, not necessarily, could, rarely,
never
I题型
Family #1Must Be or Prove Family
1.Must Be True Questions
Fact TestThe correct answer to a Must Be True
question can always be proven by referring
to the facts stated in the stimulus.
You can often predict the occurrence of
Must Bu True questions because the
stimulus of most Must Be True questions
does not contain a conclusion.Correct Answer Types•Paraphrased answers, restating a
portion of the stimulus in different
terms.
•Combination answers, resulting
from combining 2 or more
statements in the stimulus.Incorrect Answer Types•Could Be True answers;
•Exaggerated answers;
•New Info;
•Shell Game;
•The Opposite answers;
•Reverse answers.
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2.Main Point Questions
Many Main Point problems Incorrect Answer Types:Main Point---Fill in the feature a structure that Blank Questions
a. Answers that are true but places the conclusion either
do not encapsulate the The blank is always at the at the beginning or in the
author’s point;end of the stimulus. There is middle of the stimulus.
a conclusion indicator at the
b. Answers that repeat start of the sentence to help
premises of the argument.you recognized that are
being asked to fill in the
conclusion of the argument.3.Point at Issue
Incorrect Answers in Point a. Ethical versus Factual Situations;at Issue Questions
b. Dual Agreement or Dual Disagreement;
c. The View of 1 Speaker is Unknown.The Agree/Disagree TestThe correct answer must produce responses where one
speaker would say “I agree, the statement is correct” and
the other speaker would say “I disagree, the statement is
incorrect”. If those two responses are not produced, then
the answer is incorrect.
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4.Method of Reasoning
Method of Reasoning Questions TypesThe stimulus for a Method of Reasoning
question will contain an argument, and the argument can contain either valid or invalid reasoning.
You must watch for the presence of the premise and conclusion indicators.
Use Fact Test to eliminate answers. If an answer choice describes an event that did not occur in the stimulus, then that answer is incorrect.
Several types of incorrect questions:
•“New” Elements Answers;
•Half Right, Half Wrong;
•Exaggerated Answers;
•Opposite Answers;
•Reverse Answers.
Method of Reasoning—Argument Part Method—AP questions often feature 2
Questionconclusions—a main conclusion and
subsidiary conclusion—where the main conclusion is typically placed in the first or second sentence and the last sentence contains the subsidiary conclusion.
Trick: the test makers in Method—AP is to create wrong answers that describe parts of the argument other than the part named in the question stem.
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5.Flaw Questions
Common Errors of Reasoning Explained
a. Uncertain Use of a Term or Concepti. Appeal Fallacies
•Appeal to authority;
•Appeal to Popular Opinion/Appeal
to Numbers;
•Appeal to Emotion.
b. Source Argumentj. Survey Errors
ad hominem, or attack the person (or •Survey uses a biased sample;source)
•Survey questions are improperly
•Focusing on the motives of the constructed;
source;
•Respondents to the survey give
•Focusing on the actions of the inaccurate responses.
source.
c. Circular Reasoningk. Exceptional Case/Overgeneralizationd. Errors of Conditional Reasoningl. Errors of Compositions and Division
•Mistaken Negation;以偏全或以全偏概概
•Mistaken Reversal;
•Confuse a necessary condition
for a sufficient condition;
•Confuse a sufficient condition
with a required condition.
If you identify a stimulus with
conditional reasoning and are asked a Flaw
question, you can quickly scan the answers
for the one answer that contains
“Sufficient”, “Necessary” or both.
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e. Mistaken Cause and Effectm. False Analogy
•Assuming a causal relationship
on the basis of the sequence of
events;
•Assuming a causal relationship
when only a correlation exists;
•Failure to consider an alternate
cause for the effect, or an
alternate cause for both the cause
and the effect;
•Failure to consider that the events
may be reversed.
If you identify a stimulus with causal
reasoning and are asked a Flaw question,
quickly scan the answers for one that
contains “Cause”, “Effect” or both.
f. Straw Mann. False Dilemma
Ignore the actual statements made by the
opposing speaker and instead distorts and
refashions the argument.
g. General Lack of Relevant Evidence of o. Errors in the Use of Evidencethe Conclusion
•Lack of evidence for a position is
taken to prove that position is false;
•Lack of evidence against a position
is taken to prove that position is
true.
•Some evidence against a position is
taken to prove that position is false;
•Some evidence for a position is
taken to prove that position is true.h. Internal Contradictionp. time shift errors
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q. Numbers and Percentages Errors.
Author improperly equates a percentage
with a definite quantity, or when an author
uses quantity info to make a judgment
about the percentage represented by that
quantity.
6.Parallel Questions
The question stem for any Parallel question reveals whether the stimulus contains valid or
invalid reasoning. If the question stem mentions a flaw, then the reasoning is invalid. If
the question stem does not mention a flaw, then the reasoning is valid.The following elements do a. Topic of the stimulus;
not need to be paralleled:
b. The order of the presentation of the premises and
conclusions in the stimulus.
You must parallel all of a. The Method of Reasoning;
these elements:
b. The Validity of the Argument;
c. The Conclusion;
d. The Premises.
If all else fails,Create a short statement that summarizes the “action” in
the argument. Then take the abstraction and compare it to
each argument.
Family #2Help Family
7.Strengthen Questions
To effectively strengthen 3 Incorrect Answer TrapsTo strengthen a Cause and
argumentsEffect relationship
Identify the conclusion;Eliminate any alternate •Opposite answers;
causes;
Personalize the argument;•Shell game answers;
Show that when the cause
Look for weakness or holes occurs, the effect occurs;•Out of scope in the argument.
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answers.Show that when the cause
does not occur, the effect
does not occur;
Eliminate the possibility
that the stated relationship is
reversed;
Show that the data used to
make the causal statement is
accurate, or eliminate
possible problems with the
data.
8.Justify Questions
Justify FormulaThe following rules apply:
Premise + Answer Choice = Conclusiona. Any “New” element in the conclusion
will appear in the correct answer;
b. Elements that are common to the
conclusion and at least 1 premise, or to 2
premises, normally do not appear in the
correct answer;
c. Elements that appear in the premises but
not the conclusion normally appear in
correct answer.
9.Assumption Questions
The relationship between the conclusion and the assumption can be described as:
Conclusion Assumption ValidTrue
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Supporter/Defender Assumption Model
Supporter Assumption: These assumptions link together new or rogue elements in the stimulus or fill logical gaps in the argument.
Defender Assumption: These assumptions statements that eliminate ideas or assertions that would undermine the conclusion.
If there is no obvious weakness in the argument and you are faced with an Assumption question, expect to see a Defender answer choice.
Assumption Negation Technique:
a. logically negate the answer choices under consideration;
b. the negated answer choice that attacks the argument will be the correct answer.3 Quirks of Assumption Question Answer Choice:
a. Watch of answers starting with the phase “at lease one” or “at least some”;b. Avoid answers that claim an idea was the most important consideration for the author;c. Watch for the use of “not” or negatives in assumption answer choices.Assumptions and Conditionality:
a. If conditional statements are linked together in the argument, the correct answer choice for an Assumption question will typically supply a missing link in the chain;b. If no conditional chains are present and only a conditional conclusion exists, the correct answer will usually deny scenarios where the sufficient condition occurs and the necessary does not, or it works as a Defender.
Assumption and Causality: ?解题思路与Strengthen Causality题似?
a. Eliminate any alternate causes;
b. Show that when the cause occurs, the effect occurs;
c. Show that when the cause does not occur, the effect does not occur;d. Eliminate the possibility that the stated relationship is reversed;e. Show that the data used to make the causal statement is accurate, or eliminate possible problems with the data.
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10.Paradox Questions
The correct answer will The following types of Note: You must address the allow 2 sides to be factually answers are incorrect:facts of the situation. Many correct. answers will try to lure you
•explain only 1 side with reasonable solutions
that do not quite meet the of the paradox;
stated facts. These answers
•b. Similarities and are incorrect.
differences.
Family #3Hurt Family
11.Weaken Questions
Fundamental RulesCommon Weakening 3 Incorrect Answer Simple Rule for
ScenarioTrapsweakening a
conditional
reasoninga. The stimulus will To weaken a •Incomplete •Opposite
contain an argument;conditional info;answers;
conclusion, attack b. Focus on the the necessary •Improper •Shell game
conclusion;condition by comparison;answers;
showing that the c. The info in the necessary condition •Qualified •Out of stimulus is suspect. does not need to conclusion.scope There are often occur in order for answers.reasoning errors the sufficient present, and you condition to occur.must read the
argument very
carefully;
d. Weak questions
often yield strong
prephrases;
e. The answer
choices are accepted
as given, even if they
include “New” info.
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