Classic Flaws Flashcards
Possibility ≠ Certainty
- Lack of Evidence ≠ Evidence of Lacking
It’s NOT NECESSARILY TRUE, so it CANNOT BE TRUE
Ex. It has not been proven that the lack of snacks caused the Model UN tournament to be poorly attended. It could have been poorly attended because of the growing disillusionment with multi-national bureaucratic institutions. Therefore, the lack of snacks must not have been the reason. - Proof of Evidence ≠ Evidence of Proof
It COULD BE TRUE, so it MUST BE TRUE
Ex. There is some evidence that playing music turns you into a narcissist. For instance, both Kanye and Bieber are undeniably narcissists. Therefore, playing music must turn people into narcissists.
Loophole: What if lack of evidence ≠ evidence of lacking?
What if proof of evidence ≠ evidence of proof?
Bad Conditional Reasoning
When the author reads the conditionals supplied in the premises incorrectly. Never trust that the author will correctly read conditionals.
Ex. If you ride a wild horse, you are an adventurous sort. All adventurous sorts desire the thrill of the new. Therefore, if you desire the thrill of the new, you must have ridden a wild horse.
Loophole: What I’d we actually have to follow the rules of conditional reasoning?
Bad Causal Reasoning
Crazy person sees that two things are correlated and concludes that one of those things is causing the other.
Ex. Nat’s lack of chemistry with Hayden and her outlandish costumes made the Star Wars prequels borderline unwatchable. Therefore, Nat caused the temporary downfall of the franchise.
Loophole: What if one of the Omitted Options is the case?
Overgeneralization
Part ≠ All The Parts
Someone talks about something having a property and concludes that a bunch of other things also have that property.
Takes something small and turns into something big
Ex. We got better results at 70° rathe than 60°. So the hotter our lab, the better our results will be.
Paulina was quite clever in her paper on shark anatomy. So Paulina is a clever person.
Loophole: What if we can’t generalize from this one thing to a bunch of other things?
Survey Problems
There’s a survey. Someone concludes things based on the survey. There are all kinds of silent things wrong with the survey.
On the LSAT always assume that surveys are done with the highest level of incompetence.
Ex. A survey of alumni of the class of 1960 at Aurora University yielded puzzling results. When asked to indicate their academic rank, half of the respondents reported that they were in the top quarter of the graduating class in 1960.
Loophole: What if the sample was biased, the questions were biased, there are other contradictory surveys, people lie on surveys or the sample size is too small?
False Dichtomy
Someone outlines 2 possible options (this step is absent when limiting a spectrum). They eliminate one of the options. They conclude the second option must be the case.
- Limiting a spectrum
Ex. The quality of the orange zest didn’t deteriorate overnight, so it must have improved. - Limiting options
Ex. My career options include becoming an astronaut and becoming a personal assistant. Ice decided I’m afraid of space, so I’m going to be a personal assistant.
Loophole: What if there is more than 2 options?
Circular Reasoning
Crazy person concludes something. Crazy person supplies premises that assume the conclusion is already true.
Ex. Many people do not understand themselves, nor 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.
Loophole: WHat if we cant use the conclusion as evidence for itself?
Whole-to-Part and Part-to-Whole
Parts ≠ Wholes
Claims that a member of a category has a property, concludes that the category itself also has that property.
Claims that a category has a property, concludes that a member of that category also has that property.
Ex. A Starbucks location versus the Starbucks corporation
Mars versus the solar system
A member of the mock trial team versus the mock trial team
Bricks on a building versus the whole building
Loophole: What if wholes don’t necessarily equal parts?
False Starts
There’s a study with 2 groups. Researcher assumes the 2 groups are the same in all respects except those pointed out as part of the study. Researcher concludes that the differences in the study results are due to the one key difference the study is focusing on.
Ex. Researcher comparing 2 groups, one that exercises and one doesn’t. Assumes that the one that exercises is healthier. Disregards the possible differences in diet or age.
Loophole: What if the two groups were different in a key respect?
Implication
Facts ≠ Someone is believing those facts
Blair has a belief. Crazy person mentions a factual implication of that belief. Crazy person claims that Blair believes the implication of the belief.
Ex. Jose believes there is an omnipotent robot overlord in charge of our daily lives. Robot overlords always wear neckties. Therefore, Jose believes a necktie wearer is in charge of our daily lives.
Loophole: What if the person in question isn’t aware of what their belief implies?
Percentages ≠ Numbers
- Crazy person says “a percentage went up.” Concludes that the associated real number also went up.
- Crazy person says “a real number went up.” Concludes that the associated percentage also went up.
This is flawed because they always are assuming that the group size stays the same, but you have to question and call them out on this assumption. There are very different implications to the group size changing.
Ex. A commonly accepted myth is that left handed people are more prone to cause accidents than are right handed people. But this is, in fact, just a myth, as is indicated by the fact that more household accidents are caused by right handed people than are caused by left handed people.
Loophole: What if the group size is not constant?
Ad Hominem (To The Person)
Bad Proponent ≠ Bad Argument
Sane person makes a claim. Crazy person talks about how the sane person is somehow awful. Crazy person concludes that the sane person’s claim is false.
Equivocation
Crazy person uses a word or idea, intending one of its possible meanings. Crazy person concludes something using the other possible meaning of the word or idea. Hilarity ensues.
When the meaning of the word is changed throughout the argument.
Ex. Director of Ace Manufacturing Company: our management consultant proposes that we reassign staff so that 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 AMC has a long standing commitment not to exploit its workers. Therefore, implementing her recommendations would cause us to violate our own policy.
Loophole: What if we shouldn’t let words change in meaning?
Appeal Fallacies
Opinion ≠ Fact
Crazy person says that a person or group believes something. Concludes that thing must be true.
Two ways:
1. Invalid appeal to authority: when the author uses a non-expert opinion to support their conclusion
Ex. Using a baseball player to conclude something about zoology.
2. Invalid appeal to Public Opinion: because people are unreliable
Ex. 50% of Brits believe in ghosts, does that mean that ghosts are real? No.
Loophole: What if this opinion does not equal evidence of fact.
Straw Man
Sane person makes a claim. Crazy person responds to an entirely different claim, but pretends they responded to the sane person.
Ex. Ellen: Ya i turned down Harvard Law to write an LSAT book. I am so happy.
Straw Man Stranger: So what you’re saying is that you want to be poor.
Loophole: What if what they said has nothing to do with the claim they’re pretending to respond to?
