The Classic Flaws (Loophole)

bad conditional reasoning

• occurs when the author reads the conditional supplied in the premises incorrectly

• ex/ if the premises’ conditional goes unplug —> unusable but the conclusion reads the statement backworks without negating by saying unusable —> unplug — but there are plenty of other reasons why the program might not be working

• essentially the author is either concluding something by reading the conditional premises backwards without negating or by negating the conditional premises and reading it forward

bad causal reasoning

• author sees that two things are correlated but concludes that one of those things is causing the other

• look for omitted options with bad causal relationships

• ex/ natalie lack of chemistry with Hayden and her crazy outfits made the star wars prequels unwatchable. therefore, Natalie caused the temporary downfall of the franchise. — But what if actors are too insignificant to movies as a whole to cause the temporary downfall to a franchise.

whole to part & part to whole

• when the author goes from premises about all the parts of something having a certain property to a conclusion about the whole having that property or vice versa

• parts ≠ wholes

• ex/ each element of joe’s completed design is copied from different books. since no element in the design is original, then the design itself cannot be considered original — But, what if no one else has combined the elements of design the way joe did

overgeneralization

• part ≠ all the parts

• occurs when you take a premise about something specific (e.g. hot temp) and use it to conclude about temps in general

• you can’t take tiny premises and make big claims

survey problems

• surveys on the lsat are always done with a high degree of incompetence

• the problem with surveys: the author in the stimulus has concluded things based on the survey but there are all kinds of things that are/could be wrong within the survey

• ex/ biased sample, survey liars, biased questions, small survey size etc — our loophole then is : what if sample was biased, the questions were biased, sample too small etc

false starts

• the two groups being compared are always inconveniently different

• false starts — researchers always assume that the two groups are same in all respects except the ones called out as part of the study, but despite their assumption there is always the possibility btw the two groups of being different

• loophole basically would be : what if the two groups were different in a key respect

possibility ≠ certainty

• its fine to say that someone hasn’t proven their conclusion, so it’s not necessarily true but stop there, things go wrong when you say that the other person hasn’t proven their conclusion so their conclusion cannot be true

• lack of evidence ≠ evidence of lacking — it’s not necessarily true, so it cannot be true

• proof of evidence ≠ evidence of proof — it could be true, so it must be true

implication

• facts ≠ someone believing those facts

• implication tells people w that they believe, which is always dangerous

• seen when the argument starts with someone’s believe, adds in a factual premise that relates to something that person believes — and then concludes something that adds the facts to the person’s beliefs - therefore assuming too much

• ex/ bank deposits are credited on the date of the transaction only when they are made before 3 pm. Alicia knows that the bank deposit was made before 3 pm. So, Alicia knows that the bank deposit was credited on the date of the transaction. — Assumes Alicia knows about the bank deposit rule

false dichotomy

• there are more than two options

• a false dichotomy pretends there are only two options where there really could be more

• two ways to go wrong :

  • limiting a spectrum : on a spectrum you can go up, down, or stay the same. spectrum limiting authors pretend there are only two options, when there are really three. remember/ not more ≠ less & not less ≠ more

  • limiting options : pretends that there are only two options when there could be more. the loophole here is that what if there are more than just two options

• ex/ because of the teacher hiring freezes, the quality of education in that country will not improve. thus, it will surely deteriorate — limiting spectrum

• ex/ because raoul is a vegetarian, he will not have the pepperoni pizza for lunch. it follows that he will have the cheese pizza — limiting options

straw man

• arguments for cowards

• straw man arguments “ respond to an opponent by “mishearing” what was said to them + they respond to something entirely different/outlandish

• the loophole here is to ask, what if what they said has nothing to do with the claim they’re pretending to respond to

• ex/ rep: university, in expelling a student who verbally harassed his roommate, has erred by penalizing the student

  dean : but what you’re saying is that our university should endorse verbal harassment

  — the dean misdescribes the rep’s position

ad hominem

• bad proponent ≠ bad argument

• ad hominem premises insult the proponent of a position, but then the conclusion challenges the truth of the position itself. the problem is that proponent’s don’t affect the truth/falsity of their position

• ad hominem can also attack the proponent’s motivations. if the proponent is biased, it’s natural to doubt the truth of what they are claiming but you can’t fall for this on the lsat

  — a proponent’s bias for/against a position does not affect the truth or falsity of that position + premises about character and motivation only prove claims about character and motivation

• ex/ herbalist: many of my customers find that their physical coordination improves after drinking juice containing certain herbs. A few doctors assert that the herbs are potentially harmful, but doctors are always trying to maintain a monopoly over medical therapies. so there is no reason not to try my herb juice

  — the herbs could still be harmful even thou the doctors are biased

  — loophole : what if this person’s character/motivation doesn’t affect the truth?

circular reasoning

• crazy person concludes something and supplies premises that assume the conclusion is already true

  • a circular argument assumes the conclusion is true before doing the work of proving it

  • often circular arguments rule out objections to the conclusion simply because those objections are incompatible with the conclusion

• the loophole here is: what if we can’t use the conclusion as evidence for itself; the trick is also look for synonyms and similar concepts explained using different words

• ex/ many people do not understand themselves, not do they try to gain self understanding. these people might try to understand others, but these attempts are sure to fail, because without self understanding it is impossible to understand others. it is clear from this that anyone who lacks self understanding will be incapable of understanding others

  — “w/o self understanding it is impossible to understand others = “anyone who lacks self-understanding will be incapable of understanding others”

equivocation

• homonyms unleashed

• equivocation happens when the authors changes the meaning of a word throughout an argument

• you have to be vigilant to catch equivocation

• loophole here is : what if we shouldn’t let words change in meaning

• ex/ director: our management consultant proposes that we reassign staff so that all employees are doing both what they like to do and what they do well. this, she says, will increase productivity by fully exploiting our available resources”. But the company has a long standing commitment not to exploit its workers. therefore, implementing her recommendations would cause us to violate our own policy

  — the word “exploit” changes meaning throughout the two premises. the consultant means exploit as in use to full extent, and the director uses the word to refer to its more negative definition which alludes to unfairly taking advantage of someone

appeal fallacies

• appeal fallacies are about turning someone’s opinion into a fact. and this often happens in two ways

  • invalid appeal to authority : happens when the author uses a non-expert opinion to support their conclusion

  • invalid appeal to public opinion : appeals to public opinion are invalid because people are unreliable. a high percentage of people believing in anything has very little bearing on whether that thing is actually true.

• the loophole here is : what if this opinion doesn’t equal evidence of fact

• ex/ can’t use a zookeeper’s opinion to support a conclusion about baseball. zookeepers are not recognized baseball experts — invalid appeal to authority

• ex/ most people believe yawning is most powerfully triggered by seeing someone else yawn. This belief about yawning is widespread not only today, but also has been commonplace in many parts of the world. Thus, seeing someone else yawn must be the most irresistible cause of yawning — invalid appeal to public opinion

irrelevant

• occurs when the premises are entirely unrelated to the conclusion

• every flawed argument could technically be labeled irrelevant, so you need to be careful in the answer choices on classic flaw questions.

  • irrelevant is kind of a cop out, so only choose it when you don’t detect a more specific/compelling classic flaw

percentages ≠ numbers

• premises about numbers almost never lead to conclusions about percentages and vice versa

• a rising percentage doesn’t necessarily imply a rising number and vice versa — bc whenever an argument mentions numbers and percentages, they are purposefully not mentioning group size

• percentages ≠ numbers always assume group size remains the same

• the lsat wants you to call them on their assumption that group sizes stays the same