LSAT logical reasoning Powerscore
Fam 4
Cannot be true questions Rules: 1) Accept the stimmy info--even if it contains an error of reasoning--and use the info to prove one answer must be true 2)If an answer contains info not directly in the stimmy, then this answer could be true and is incorrect! --The correct answer choice directly disagrees with the stimmy or a consequence of the stimmy
Family 1
Cannot bring new info off the page in. Stimulus stated is accepted as given -If an answer choice mentions something that is not included or encompassed by the stimmy, it is incorrect Includes: must be true main point disagree/agree method of reasoning flaw parallel reasoning/flaw
Conditional reasoning (147)
Comprised of at least one sufficient and at least one necessary condition Sufficient: an event or circumstance whose occurrence indicates that a necessary condition must also occur Necessary: an event or circumstance whose occurrence is required in order for a sufficient condition to occur -Sufficient conditions do not make the necessary condition occur. It does not actively cause the necessary to happen. Just the presence of a sufficient means a necessary will occur
justify conclusion question examples 306
Conclusion above follows logically if which one of the following is assumed? Which one of the following, if assumed, would allow the conclusion to be properly drawn? Which one of the following, if assumed, enables the argument's conclusion to be properly inferred? Which one of the following is an assumption that would serve to justify the conclusion above? Conclusion would be properly drawn if it were true that the..."
Conform and judgement (principle questions) pg 591
Conform: When answer choices are said to conform to the stimmy, likely is a MBT or most strongly supported Q When stimmy is said to conform to one of the principles in the ANSWER choice, likely facing a strengthen or justify question Judgement: usually a parallel question
Evaluate the argument
Consider the question or piece of info that would be help determine the validity of the argument in the stimmy -Identify a piece of info to help assess the argument Seen with words: evaluate, judge, assess
Errors of conditional reasoning (pg 463)
If you see conditional language in a flaw question, it is one of these! Confusing a necessary condition for a sufficient condition: 'It acts as if something that is necessary for a good leader is something that is sufficient to create one' Confuses a sufficient condition for a necessary condition: 'Confuses a sufficient condition with a required condition
Family 1 of questions: Prove
Includes: must be true main point disagree/agree method of reasoning flaw parallel reasoning/flaw Goes from stimulus to answer choices
Only
Indicates a necessary condition. But can be an exception: "The only way to achieve success is to work hard." -Diagrammed as AS -> WH --Odd as only indicates necessary, but here only modifies way". And the "only way" refers to working hard. Thus, "work had" is the necessary
Inference vs assumption
Inference: In LSAT lingo, something that must be true! An item of proof must be in the argument Assumption: An unstated premise essentially. What must be true in order for the argument to be true Difference: Inference is what follows from an argument (conclusion). Assumption is what is taken for granted while making an argument
Main Point Questions pg. 138ish (easy)
It is the conclusion!!! Look out for intermediary conclusions
Numbers and Percentages misconceptions 1-3
Misconception 1: Increasing % leads to increasing numbers (NOT TRUE) EX: X increased market share from 10% to 25% this year. Therefore, they are selling more cars this year. --Not necessarily true. What if total number of cars decreased from last yr from 1000 to 250? that would help #2: Decreasing % leads to decreasing numbers: Opposite of 1 #3: Increasing numbers automatically leads to increasing percentages EX: number of bike accidents rose dramatically this month. So, bike related accidents must account for a greater percentage of total road accidents" Nah total road accidents cud have sky rocketed and decreased bike accident percentage
Main conclusion and subsidiary ones in AP method of reaosning
Most of these questions have a main and sub conclusion. Subsidiary: often proceeded by a conclusion indicator; 'thus, therefore, etc'. Usually in the last sentence to trick you into thinking it is the main Main: has no such vocab typically, usually also in first or second sentence
Resolve paradox questions
Must address the the facts of the situation. Many incorrect answers will lure you in with reasonable solutions that do not meet the stated facts Answers allow both sides to be factually correct -do not overthink this question type
CBT tips
Occurrence of necessary condition does not automatically lead to the occurrence of the sufficient Occurrence of necessary condition could lead to the occurrence of the sufficient
Principle questions cont'd
Often in conditional language and broad as most principles just are generally. Parallel Principle question: -Not trying to find matching direct reasoning, but find answer following application of principle --can usually make diagram as conditional language often used here
Conditional tip
On LSAT, when an author makes a conditional statements, they believe that statement to be true without exception. Could not have cheated to get an A+ or anything. ex: If someone gets an A+ on a test (sufficient), they must have studied for the test (necessary) --To the author here, anyone who got an A+ MUST have studied. Studying had to have occurred.
Point of agreement 582
Opposite of disagreement questions
Abstract wording (flaw q's a lot)
Pay attention to this. how an answer choice can be more abstract then that of the stimmy. Writers do it to hide something...
Assumption tip
If there is no obvious weakness in the argument and you are faced with an assumption question, expect a Defender question
Principle questions
are not a separate question but the principle overlay appearing in various question types like (strengthen, justify, CBT, etc. Seen as: 'Which one of the following PRINCIPLES most helps justify the reasoning above (strengthen) 'Which one of the following most accurately expresses the principle underlying the argumentation above (justify)
Numbers and percentage errors
occurs when an author improperly equates a percentage with a definite quantity or vice versa. Can be seen as: 'the argument confuses an increase in market share with an increase in overall revenue'
Justify the Conclusion Questions (aka sufficient assumptions) looks like
"The conclusion above follows logically if which one of the following is assumed?" Most contain 3 indicators/features: 1. stem uses the word 'if' or another sufficient condition indicator 2. Stem uses the phrase 'allows the/enables the conclusion to properly be drawn'. BIG tip off 3. Stem does not lessen the degree of justification. ---You will not see the words 'most justifies' or 'does the most to justify' here as we need 100% valid conclusion. Note: 'Most justify' will be strengthen Note: 1 and 2 are not always present-sometimes just one, or maybe none. 3 always is present though
LG quick tip
"either x or y in, but not both" This equals a BiConditional!!
Numbers and Percentages misconceptions 4-6
#4. Decreasing numbers leads to decreasing percentages: opposite of 3 #5: Large numbers mean large percentages, small numbers mean small % #6: Large percentages mean large numbers, and small % mean small numbers
Negating Conditional Statements
'To be rich, you must be smart' becomes: 'To be rich, you DO NOT NECESSARILY have to be smart' Show the necessary condition is not necessary. Original statement: If A, then B diagram: A->B Logical negation: A-> NOT B Mistaken negation (do not be confused): Not A ->Not B
biconditional statements pg 189
'if and only if' Seen in instances of not only 'if and only if' but also: 'if but only if' 'then and only then' 'then but only then' 'when and only when' 'when but only when' 'all but only' ---These have a sufficient condition indicator and necessary condition indicator joined by 'and' or 'but' EX: Ann will attend if and only if Basil attends 'if and only if' Effectively creates two separate conditional statements: 1. A if B. Diagrammed as: B -> A 2. A only if B. Diagrammed as: A -> B Combined, we get a double arrow: A <-> B Therefore, only either A n B do not attend, or both attend. Cannot be just one in attendance!
Family 1 cont'd
-"The info above, if true..." 1) Accept the stimmy info--even if it contains an error of reasoning--and use the info to prove one answer must be true 2) Info not directly in the stimmy or under the umbrella of a concept in the stimmy is wrong
Fam 2
-Accept the answer choices as given to be true. Even if they include elements not mentioned in the stimmy -"Which one of the following, if true..." Rules: 1) There is an error present in the stimmy and you identify it 2) Answer choices are accepted as given, even if they contain "new" info. You determine which choice best meets the question posed in the stem. Includes: Assumption (necessary assumption) justify the conclusion strengthen/support resolve paradox
Test tips
-D is best guess choice -For LR, D and E make up most of answer choices
"Than either" questions
-Either translates to both EX: I like Bio better than either Chem or Physics --Means I like Bio better than both (individually, not combined) Chem or Physics. Like Bio better than Chem. Like Bio better than Physics
Assumption questions 327 (necessary assumption)
-Has to be fully correct, usually soft logical force -a 'minimalist' answer: Statement must be something the author believed when forming the argument -Cannot contain extraneous info ---EX: 'All dogs are intelligent'. Answer choice of "All dogs and cats are intelligent" would not work; we do not know about cats
Sufficient assumption Q: how to supply 'most' relationship to 'some' in conclusion
-Have another 'most' branch off the initial 'most conditional EX: Most of the members of BUN 17 of the government employees union are computer programmers. Thus, it is certain that some of the gov't employees who work with Hanson Building are computer programmers since ____. Logic: P1: 17 ->(most) CP C: Hanson ->(some) CP P2 (answer/link): 17 ->(most) Hanson correct answer: Most of the members of BUN 17 work in the Hanson building
Causality in premise or conlcusion
-If in conclusion, be skeptical
Principle question review
-Parallel questions: use the principle presented in the stimmy and apply it to the situation in each answer choice -strengthen questions: each answer choice contains a principle that acts an an additional, broad premise supporting or proving the conclusion (5 diff principles here)
Diagramming either/or statements
-either or in LSAT world means "at least 1, maybe both" -"at least one of the two, possibly both" is the same as either...or in LSAT In normal world, it means this or that. NOT IN LSAT EX: Either Jack or John will go to the party --Not John -> Jack --Not Jack -> John
Justify the conclusion 303
-like sufficient assumption. Gotta make the conclusion 100% proven. Nothing less premise + answer choice =conclusion -bridge the gap EX: P1: John has 2 apples P2: ? Conclusion: John has 5 apples P2: is the gap-3 apples
approaching questions
-they say read stimmy first. Not the question, to save time
Unless equation
1) Whatever term is modified by "unless," "except," "until," or "without" becomes the necessary condition. 2) The remaining term is negated and becomes the sufficient condition ex: Unless a person studies, he or she will not receive an A -Turns into: He will receive an A if he studies ex: There can be no peace without justice -Turns into: if peace occurs, there must be justice
Justify fill in the blank telling signs (easy to identify)
1. Blank in the stimulus is preceded by a premise indicator (because, since, etc.) 2. Wording of the stem shows you it is a justify ---'The conclusion of the argument is properly drawn if which one of the following completes the passage?
Appeal fallacies- 3 most commons
1. Appeal to authority: using the opinion of an authority in an attempt to persuade the reader. Flaw here is that authority may not have relevant knowledge or all the info regarding the situation; or there may be a difference of opinion among experts Seen as: 'Judgement of experts is applied to a manner in which their expertise is not relevant' 2. Appeal to popular opinion/numbers States that a position is true because a majority believe it so Seen as: 'Argument tries to undermine the claim by appealing to public opinion' 'Popular sentiment is treated as definitive proof of a claim' 3. Appeals to emotion Emotion/emotionally charged language is used in an attempt to persuade. ex: 'Officer please do not give me a ticket. In last month i have been fired from my job, lost girl friend and kicked out of apartment. I do not need this' Seen as: 'Attempts to persuade by making an emotional appeal' 'Argument appeals to emotion rather than reason'
Causality vs conditonality
1. Chronology: cause must happen before the effect naturally. Sufficient condition can happen before, after or same time as a necessary 2. Connection: Cause makes the effect happen. In conditional, the sufficient and necessary conditions are often related directly, but they do not have to be ex: before the war can end, I must eat this ice cream. --sufficient does not make the necessary happen, it just indicates that it must occur 3. Language used to introduce the statements is different. Causal indicators are usually very powerful, conditionals not
Causality in strengthen questions
1. Eliminate any alternate causes for the stated effect 2. Show that when the cause occurs, the effect occurs 3. Show that when the cause does not occur, the effect does not occur. 4. Eliminate the possibility that the stated relationship is reversed. 5. Show that the data used to make the causal statement are accurate or eliminate possible problems with the data.
Assumptions and causality: typical correct answer categories pg 346
1. Eliminates alternate cause -Because author believes there is only one cause (one stated in argument) author assumes no other cause exists 2. When cause occurs, effect occurs 3. shows when causes does not occur, effect does not occur 4. Eliminates possibility that the relationship is reversed -Because author believes the cause and effect relationship is correctly stated, author assumes relationship here cannot be backwards 5. Shows data to make the causal statement is accurate, or eliminates problem with the data ALL similar to strengthen answers
Logic ladder
All Most Some -If something says all kids like ice cream, you automoatically know most and some do too. It goes down like that -If only 'some' do, you cannot say for that most or all would Negative: None Most are not some are not
Number and percentage tips
1. If stimmy contains percentage info only, avoid answers with hard numbers EX: stimmy: market share of X declined. Avoid: X sold small amount/greater amount 2. Stimmy has numerical info only, avoid percentage or proportion info EX: stimmy: Y sold fewer computers this year Avoid: Y has lower market share now 3. If stimmy has both % and numerical info, any answer can be true
Flaw question types: Error in assessing the force of evidence
1. Lack of evidence is taken to prove that a position is false EX: 'White house has failed to offer any evidence that they have reached a trade agreement with china. Therefore, no such agreement happened --Just because there is no evidence does not mean it is false. Maybe it is classified so they had to hold onto info. Lack of info does not undeniably prove that a trade agreement has not been reached Can be seen as: 'Treats failure to prove a claim as constituting denial of that claim' 2. lack of evidence to prove a position is true -opposite of above. Just because no evidence disproving, does not mean it is true EX: There has been no evidence against the existence of God, so God must exist Seen as: 'Treating the failure to prove a claim to be false as if it is a demonstration of the truth of that claim
What to look for for parallel answers
1. Matching method of reasoning (conditional reasoning, analogy, etc.) 2. Match the conclusion: time saver. matching language (most, none, etc.) 3. Match the premises: similar to conclusion 4. Match the validity of the argument: eliminate answer with not equivalent logical force
Basic errors of causality
1. One event occurs before another: when one event occurs before another, many fall into a trap of thinking the first caused the second. Not always the case -EX: Every morning the rooster crows before the sun rises. Hence, the rooster must cause the sun to rise 2. 2 or more events occur at the same time: Many assume one caused the other. But the 2 could be the result of a 3rd event, or two correlated without causation. -EX: Consumption of ice cream has been found to positively correlate with murder rate. Therefore, consuming ice cream must cause one to be more likely to murder. ---both could be explained as effects of a cause: hot weather.
Weaken answer traps
1. Opposite answers: these strengthen actually 2. Shell game: similar concept or idea in an answer, but changed just enough to be wrong 3. Out of scope: answer misses the point of the argument and raises issues not related to or not tangential to the argument Note: Look for answers that attack conclusion and pay attention closely. Look out for hell answers
Identifying Assumption
1. Stem uses words like 'assumption' 'presupposition' or etc. 2. Stem NEVER uses word 'if' or any other sufficient indicator Important: Assumption are necessary part of the argument, so will contain indicators for such like 'required' or 'unless' etc. Appearance of a sufficient indicator means either justify or strengthen (IMPORTANT) EX's: "Which one of the following is an assumption required by the argument above" 'Argument assumes which one of the following' 'Position taken above presupposes which one of the following'
Survey errors flaw
1. Using a biased sample: sending survey only to red states and say Trump will win election of their info back 2. Questions not constructed well: Confusing or misleading 3. Inaccurate answers: lie about how much they earn or certain things to look good Seen as: 'generalizes from an unrepresentative sample' 'Uses evidence drawn from a sample that may not be representative'
3 tips for assumption questions
1. answers with "at least" usually right. Soft logical force 2. Answers with 'the top priority/primary purpose/main factor' are wrong 3. Do not rule out answers with a negative answer choice
Incorrect method of reasoning answers
1. new element answers - an answer that describes something that did not occur or describes an element new to the argument cannot be correct 2. Half right, half wrong answers - LSAT makers like to start off with something that happened, then end with something that did not. Half wrong=ALL wrong 3. Exaggerated answers - take a situation from the stimulus and stretch that situation to make an extreme statement that is not supported by the stimulus. Just because an answer choice contains extreme language DOES NOT mean that the answer is incorrect! 4. The Opposite Answer 5. The Reverse Answer - these are attractive because they contain familiar elements from the stimulus, but reverses them in the answer.
look out for in solving justify conclusion q's: Mechanistic (justify formula) approach
1. new info in conclusion will be included in the answer 2. Elements that are common to the conclusion and at least one premise normally are not in the right answer 3. Elements that appear in the premise but not the conclusion are typically right
THings to look out for on justify q's 314
1. rewording elements: 'boycott' in premise turns into 'action'. Mean same, but LSAT trying to trip you up 2. Distractor elements: provide background info or are not essential to the main argument. But confusing because they are in the stimmy to begin. EX: P1: A->B P2: D->B Conclusion: A->C Answer? B->C. Ignore D
Strengthen q's
1. usually use word strength or synonym (support, helps, most justifies) 2. stem indicates the answer choices should be accepted as true (which one of the following, if true...) EX: Which one of the following, if true, most strongly/strengthens supports the statement/argument above
Valid and invalid
151 pg
Flaw question types: Error in assessing the force of evidence PART 2
3. Some evidence against a position is taken to show a position is false This can weaken a position, but not necessarily show it to be false EX: Some claim that a lengthy drought preceded the fall of the Aztec Empire. But we know from Aztec writings that in at least one year during the supposed drought there was minor flooding. Thus, the claim that there was a lengthy drought prior to the fall of the Aztec empire is false." -Shows that minor flooding would weaken claim of lengthy drought. But not kill it as it is possible for flooding to occur on occasion, but not enough to overcome general drought conditions Seen as: Confuses weakening an argument in support of a given conclusion with proving the conclusion to be false"
Mistaken cause and effect (flaw)
4 types: 1. Assuming a causal relationship on the basis of the sequence of events. 'Mistakes the occurrence of one event after another for proof that the second event is the result of the first' 2. Assuming a causal relationship when only a correlation exists. 'Confusing the coincidence of two events with a causal relation between the two 3. Failure to consider an alternate cause for the effect, or alternate cause for both cause and effect 'Overlooks possibility that the same thing may causally contribute to both 4. Failure to consider that the events may be reversed 'Author mistakes an effect for a cause IF YOU SEE a stimmy with causal reasoning, go to answers with such
Flaw question types: Error in assessing the force of evidence PART 3
4. Some evidence for a position is take to prove that position is true. Seen as: Argument treats evidence showing mere plausibility as if it proves that the conclusion is in fact true EX: We know that the defendant was in the vicinity of the robbery when it occurred. Therefore, the defendant is guilty of the robbery -Partial support does not make the position invincible and correct
Conditional chain seen in sufficient (justify conclusion) assumption q's. tough ones
A-B-C-D Conclusion: Not A A correct answer here would be a NOT D, or a NOT C -When there is nothing to fill in the gap
Cannot be true questions (infrequent) 563 for explanation
Accept stimmy info and look for answer choice that can not be true (duh) Seen with saying CANNOT be true, or true EXCEPT, or one must be false IF in conditional form, chain the statements and see from there. --One scenario NOT in CBT questions is sufficient occurring and the necessary not --If an answer choice has necessary occurring but not the sufficient, this is ok and possible answer choice!
"Only" "Only if" "The Only" pg 184
All are necessary indicators. --Only and only if directly precede a necessary condition, whereas "the only" directly precedes a sufficient (important)! The only works in same way as only EX: The only way to become rich is to work hard Only modifies "way" and way refers to "work hard". So diagram is: Rich -> work hard -Another way to think of "the only" is to think of it as a sufficient condition indicator that modifies the condition that immediately follows it EX 2: The only people who like parties are extroverts The only is followed by people who like parties. This is the sufficient condition
all, most, some, etc. meanings in LSAT
All=100 Most = 51-100 (majority) Some are not = 0-99 (not all) Most are not = 0-49 Some = 1-100 (at least one) None = 0
Assumption v. MBT
Assumption contain statements that were 'used to make' the conclusion (before) MBT contain statements that 'follow from' the argument in the stimmy (after)
Source Argument (Ad Hominem) Flaw questions
Attacking the person or source instead of the actual argument itself Easiest flaw type Seen as: 'it is directed against the proponent of a claim rather than against the claim itself" 'Draws conclusions about the validity of a position from evidence about the persons source (!) 'Assuming that legislation should not be supported based on the character of some supporters of the legislation
Straw man flaw
Attacks opponents position by ignoring actual statements by the opposition and instead distorting and refashioning the argument, making it weaker in the process Seen as: 'Distorts the proposal advocated by opponents' 'Misdescribing the opposing position, thus making it easier to challenge' 'Refutes a distorted version of an opposing position'
Parallel chaining little tip
C->SBO->(most)CM->S C: C->(most)S the conclusion is flawed as you cannot chain this, given the SBO has most, not the C. You could do SBO ->(most)C; but not C as there is a block. The most blocks it here
MBT wrong answers
Could be true/possibly true: not must be exaggerated answers: taking info from stimmy and broadening it to a statement not supported by the stimmy --EX: changing some in stimmy to most/all in answer Shell game: idea raised in stimmy and similar idea in answer, but the idea is changed just enough to be incorrect, while still attractive. Reverse answer: Many people like some kind of music." to "Some people like many kinds of music." changed up
Double not arrow
EX: If G runs for president, then H will not run for president diagrammed: G -> Not H Contra: H -> Not G Only one runs. so as seen in LG it is like: G <-Not->H -Only possible scenario that cannot happen here is both run!. G can run, H only can run, or neither could
Multiple sufficient conditions pg 187
EX: If you are rich and famous, then you are happy Diagram: Rich AND famous -> happy Contra: Not happy -> not rich OR not famous -Vice versa if stimmy had "or" instead of 'and'
Multiple necessary conditions pg. 186
EX: To graduate from Bates you must be both smart and resourceful diagrammed as: graduate -> Smart (1) and resourceful (2) contra: Not smart OR not resourceful -> not graduate -Only one needs to be not met to fail this. "and" becomes "or" in contra here. Vice versa if stimmy had or instead of "and" See below EX 2: To graduate from Bates you must be both smart or resourceful diagrammed as: graduate -> Smart (1) or resourceful (2) Contra: Not smart AND not resourceful -> not graduate
Logical negation important dummie
EX: if A then B LOGICAL negation: If A then NOT B Mistaken negation: NOT A then NOT B Keep sufficient condition and use logical negation
Most Strongly Supported Questions
EXs: "The statements provide the most support (!) for which one of the following?" "Which one of the following is most supported by the info above?"
MBT questions (stimmy to answer)
EXs: If statements above are true, which of the following must also be true? "If the info above is correct, which one of the following conclusions can be properly drawn on the basis of it? "Which one of the following can be properly inferred from the statements?"
Conclusion/premise indicator
EXs: Therefore, since. Thus, because. Hence, due to... -Even though conclusion language is first, a premise follows due to the comma after therefore. EX: Therefore, because higher debt has forced consumers to lower their savings, banks now have less money to loan. ---Conclusion is banks now have less money to loan
Solving Parallel reasoning questions (important)
Elements that DO NOT need to be parallel with stimmy and answer: 1. Topic of stimmy: it is irrelevant as you are looking at the skeleton/structure of argument --If they have same topic, usually that answer is wrong 2. Order of presentation of the premises and conclusion Elements that DO need to be parallel: 1. Method of reasoning 2. Arguments validity --Sometimes in flawed reasoning, an answer is incorrect because the argument is valid 3. Conclusion certainty matches: 'must/always/never/sometimes, etc. --A conditional conclusion in the stimmy will be matched by a conditional conclusion in the answer ---Pay attention to switches in indicators: majority switching into most, etc. ----Look at negatives and do not eliminate just because of such: "the council member must be present at the meeting" pretty much same as "The councilmember must not be absent from the meeting" 4. The premises: 'must/always/never/sometimes' apply the same
Error of composition and division (Part to whole flaw)
Error of composition: assigning a characteristic of part of the group to the group as a whole or to each member of the group Seen as: takes belief of one to represent the belief of all' 'Assumes that because something is true of each of the parts of a whole it is true of the whole itself' Error of division: Author attributes characteristic of the whole (or each member of the whole) to a part of the group EX: America is wealthiest country in the world. Thus, every American is wealthy Seen as: 'Presumes without warrant that what is true of a whole must also be true of each of its arts
Flaw question types: Errors in use of evidence pg 455
Failing to use info correctly Lack of Relevant evidence for the conclusion: -Citing irrelevant evidence in an attempt to refute/reach a claim --seen as "author cites irrelevant data/draws a conclusion not warranted by the evidence provided/fails to give any reason for the judgement it reaches
false analogy fallacy
Fallacy in which the premises are based on two or more cases that contain more differences than similarities Seen as: 'Treats two very different cases as if they are similar'
Chapter 7 pg 217. Weaken questions
Focus on conclusion -Answer choices are true. Their new info is no problem -personalizing the argument can help: how would I respond to the author here? Common logical fallacies: 1. Incomplete info: author does not consider all possibilities 2. Improper comparison: author compares items that are essentially different 3. Overly broad conclusion: Author draws a conclusion that is too broad or expansive than the premises support
additional premise indicators
Furthermore Moreover Besides In addition What's more After all -These add info not always entirely necessary for the argument (not the most important premise), but important to note and possibly use
Family 2: Help
Goes from answer choices to stimulus Includes: Assumption (necessary assumption) justify the conclusion strengthen/support resolve paradox
Family 4: Disprove
Goes from stimmy to answer choices Cannot be true
Conditional Linking Important!
If an identical condition is sufficient in one statement, but necessary in another, a chain and can be linked! EX: P1: A -> B P2: B -> C Chain: A -> B -> C Inference: A ->C Contra here: Not C -> Not A Note: Contrapositive of final link is usually the answer choice
Tackling question
If stimmy contains an argument-identify the conclusion If stimmy contains a fact set-examine each fact
Must be true/most suported
If the statements above are true, which one of the following must also be true? Which one of the following can be properly inferred from the passage?
Formal logic 379 (big chapter)
Like intro to logic at bates Do not think this is necessary Look at in questions where you see "some, most, all" a lot. Often in MBT questions
Parallel little tip
Look at contrapositives possibly too to help link things
Disagree/point of issue questions 573
Look out for: 1. ethical vs factual situations 2. Dual agreement or dual disagreement
Flaw in reasoning q's
Same as method as you look at the skeleton of the argument, but you identify why it is flawed of course
Variance test (evaluating the argument question
See an answer choice, and then take two extreme hypotheticals from the original answer choice. If one strengthens and one weakens, you got a winner
Circular reasoning
Seen as: 'presupposes what it sets out to prove' 'It assumes what it is attempting to demonstrate' Author assumes as true what is supposed to be proved EX: This essay is the best because it is better than all the others --Premise and conclusion are identical in meaning so both support one another equally creating a circle
Pseudo Sufficient Assumption
Similar, but look for 'most helps to justify' typical question will be: P1: A C: B Answer: A->B
Unless, except, without and until
Special process 1)Whatever term is modified by these, becomes the necessary 2)Remaining term is negated and becomes the sufficient
MBT GOOD EX:
Stimmy has conditional reasoning and is a MBT question, immediately look for the repeat or contrapositive in the answer choices! Avoid mistaken reversals or negations
Strengthen vs must be true
Strengthen/support: Which one of the following, if true, provides the most support for the argument? (Answer to stimmy) MBT: The statements above, if true, most strongly support which one of the following? (Stimmy to answer)
Strengthen v Justify the conclusion v Assumption
Strengthen: Support argument, intuitive Justify: Asks you to strengthen argument so much, the conclusion is made logical (sufficient assumption). The answer must make the conclusion 100% proven, nothing less. Assumption: Identify a statement that the argument assumes. Assumption is an unstated premise-what must be true in order for the argument to be true. (necessary assumption: usually soft force)
Review page 200
Sufficient words: if when whenever every all any each in order to people who Necessary indicators: then only only if must required unless except until without
Supporter/defender assumption model 329
Supporter: Linking role; an assumption connects the pieces of the argument EX: All male citizens of Athens had the right to vote. Therefore, Socrates had the right to vote in Athens' --linking assumption is Socrates is a male of Athens. Defender: Protects argument by eliminating ideas that could weaken the argument --When you read an LSAT argument from mind of the author, they believe their argument is sound. They do not knowingly make errors of reasoning and means the points they raised and conclusions they make have been well-considered and are airtight --EX: 'People who read a lot are more intelligent than others. Thus reading must cause a person to be intelligent.' ---In author's mind here, all other explanations are assumed not to exist; an idea that would undermine the argument here is impossible and cannot occur. ---Statements that would undermine: "Genetics causes a person to be intelligent' or 'Regular exercise causes a person to be intelligent." --Author assumes here that these are not possible. Therefore, 'Genetics does not cause a person to be intelligent' -Defenders attack 'what if' scenarios that would undermine an argument
Supporter/defender simplified
Supporter: links together new or rogue elements in the stimulus or fills logical gaps Defender: eliminates ideas or assertions that would undermine the conclusion. 'Defends' argument by showing that a possible alternative is not viable
Flaw saying "takes for granted"
That means 'it assumes' so look at it as an assumption question!
Indicator words ex
To get an A, you must study Studying is necessary to get an A When someone gets an A, it shows they must have studied Only someone who studies can get an A You will get an A only if you study ---All of these are diagrammed the same: -A (sufficient) -> Study (necessary)
Weakening conditional reasoning q's 229
To weaken a conditional conclusion, attack the necessary condition to show that the necessary does not need to occur in order for the sufficient to occur. -Can be achieved by showing a counterexample or by presenting info that shows the sufficient can occur without the necessary So: When you have conditional reasoning in the stimmy on a weaken question, look for an answer that attacks the idea that the necessary condition is required`
Unless prob ex 198
Unless they find an eyewitness and put the defendant on the stand, they will lose the case Diagrammed: Not LC -> FE and DS Contra: Not FE or Not DS -> LC
Most strongly supported q's
Very similar to MBT but question stem reduces degree of certainty by substituting 'most strongly supported' for say 'must be true/infer/etc.'
Family 3: Hurt (pg 67)
Weaken Goes from answer choices to stimmy
fam 3
Weaken questions Rules: 1) There is an error present in the stimmy and you identify it 2) Answer choices are accepted as given, even if they contain "new" info. You determine which choice best meets the question posed in the stem.
Central assumption of basic causal conclusions 251
When an LSAT speaker concludes that one occurrence definitely caused another, that speaker also assumes that the stated cause is the ONLY possibly cause of the effect and that the stated cause will ALWAYS produce the effect. -Every argument with basic causal conclusion on LSAT, speaker believes stated cause is the only cause and all other theoretical possibly causes are not actual causes!!! ---A normal person would say yes maybe this is a cause but what about xy and z? Not on the LSAT
Principle questions looking at answers with conditional language (IMPORTANT)
When looking at possible answers, here are some things to remember you CAN CONCLUDE based off of conditional statements: 1. If sufficient condition is met in one of the answer choices, then it can be concluded necessary has occurred 2. If necessary is not met in one of the answer choices, can be concluded sufficient has not occurred (contrapositive) Things you CANNOT Conclude: 1. If sufficient is not met in one of the scenarios in the answer choice, you can conclude that the necessary has not occurred --NO this is a mistaken negation 2. IF necessary is met in one of the scenarios in the answer choice, you can conclude sufficient has occurred. --NO this is a mistaken reversal
AP (Argument part) Method of reasoning q's
Where they cite a specific point of the stimmy and ask you to identify the role it played in the argument -not terribly hard
MBT question type (140)
Which one of the following can be inferred from the passage above? infer=MBY
Justify the conclusion
Which one of the following, if assumed, would allow the conclusion to be properly drawn?
Cause and effect 248
Words to look out for: caused by because of responsible for reason for leads to induced by promoted by determined by product of is an effect of
Uncertain Use of a Term or Concept
as an argument progresses, the author must use each term in a constant, coherent fashion. using a term in different ways is inherently confusing and undermines the integrity of the argument. Seen as: 'confuses two different meaning of the word 'genius''
Flaw negations
can possibly be mistaken negations and mistaken reversals EX: Since the handwriting is not Millers, the joker is not Miller's Answer choice: If the handwriting had been Millers, then the identity on the note would have been ascertained to be Millers (Mistaken negation)
possible/probable causes vs certain cause 258
certain: must (see slides above) possible/probably: likely, could, probably Possible/probable can change answers: EX: Pollen count is high today and I am suffering from sniffles. So my sniffles are probably (!) the result of today's high pollen count Answer choice for a Weaken question: A) Exposure to certain foods can also cause congestion ---This would present an alternate cause and work IF the conclusion was absolute. Since it is not, does not work fully! Best way for attacking possible cause weaken questions is: Show relationship is reversed, raise possible third cause causing them both
414 for logic formal examples
dd
Method of reasoning pg 423
describing how the argument proceeds ex: 'Method of the argument is to/argument proceeds by/argument derives its conclusion by?' Hard to prephrase, just do a general one and then look at the answers that best describes it Watch out for answers which are partially true --EX: "The argument accepts a claim on the basis of public opinion of the claim" Better be true that in the argument, the author identifiably accepted a claim and that it is done indeed on the basis of public opinion
pg 210. GOOD FOR REVIEW
f
Right answers on causal connections
find alternate causes show effect does not occur show cause does not occur show effect here causes the cause (reverse)
Principle
if necessary conclusion is met, does not mean sufficient is! look at previous slide
Conditional Linking 172 onward. LOOK At closely!
look at
few
maybe helpful. the word 'few' means logically some are or most are not. LSAT cares more about 'most are not'; apparently
False dilemma
occurs when it is suggested that only two alternatives exist even though there may be others Do not confuse when an argument is clearly seen as only A or B. "Either A or B will occur, but not both"
Shell game ex:
page 112
MBT correct answers
paraphrased answers: diff language but same concepts combination answers: combining two or more statements in the stimmy
Strengthen 279 pg.
pay attention to conclusion Info in stimmy is suspect, focus carefully the answer choices are accepted as given, even though they bring in new info
New info on MBT questions
pg 102/103
Unless equation simplified for u dummy
phrase modified by 'unless' becomes the necessary and remainder is negated and becomes the sufficient EX: A gift is not generous unless it is intended to benefit the recipient and is worth more than what is expected or customary in the situation G=gift is generous BR=gift is intended to benefit the recipient WM=Gift is worth more than what is expected or customary in the situation Seen as: G -> BR + WM
General tip: Read better and pay attention to words like
probably, some, most, all, etc.
Flaw question types: Internal contradiction
self contradicting seen as: bases a conclusion on claims that are inconsistent with each other/author makes irreconcilable presuppositions/etc. conflicting
Flaw question types: Exception case/overgeneralization
takes a small occurrence and treats it to be a big, maybe always occurring event Seen as: Supports a general claim on the basis of a single example/generalizes on the basis of what could be exceptional cases/ etc.
Time Shift Errors
the mistake involves assuming that conditions will remain constant over time, and that what was the case in the past will be the case in the present or the future Seen as: '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'
Most, if not all
this is redundant Most = 51-100 (majority) Therefore if you see this, it can be either a majority, or up to all of it
Negating assumption answers
to double check -Negated choice that weakens the argument will be the correct answer Use logical opposite rather than polar opposite!!! -ex: what is logical opposite of sweet? --Polar opp: sour --logical opp: NOT sweet logical opp of some? None. Divides into two categories