Flaws

Question 1

Causal Flaw

Answer 1

Description: Mistakes a correlation for causation, assuming that just because two things happen together, one caused the other.

Example: “Every time I see Paul, it rains. Therefore, Paul causes it to rain.”

Question 2

Conditional Logic Flaw

Answer 2

Description: Incorrectly interprets or manipulates conditional statements. This includes flaws like:
- Mistaken Reversal: Treats a conditional statement’s necessary condition as sufficient.
-Mistaken Negation: Incorrectly negates a conditional statement.

Example: “If I pass the LSAT, I will become a lawyer. I’m not going to be a lawyer, so I won’t pass the LSAT.”

Question 3

Comparison Flaw

Answer 3

Description: Assumes that because two things are similar in one respect, they must be similar in another.

Example: “Since medicine A and medicine B are both antibiotics, medicine A must be as effective as medicine B.”

Question 4

False Dichotomy

Answer 4

Description: Treats two or more options as the only possibilities when there may be others.

Example: “Either you support increased funding for public schools, or you don’t care about education.”

Question 5

Overgeneralization

Answer 5

Description: Draws a broad conclusion based on a limited or small sample.

Example: “I met two people from New York who were rude, so all New Yorkers must be rude

Question 6

Appeal to Authority

Answer 6

Description: Assumes that something is true because an authority or expert said so, even if they are not qualified in the specific area.

Example: “A famous actor says this skincare product is the best on the market, so it must be effective.”

Question 7

Appeal to Popular Opinion (Bandwagon Fallacy)

Answer 7

Description: Assumes something is true or correct just because it’s popular.

Example: “Most people believe in astrology, so it must be valid.”

Question 8

Appeal to Emotion

Answer 8

Description: Attempts to manipulate emotions rather than provide a logical reason.

Example: “You should donate to our cause, or innocent children will continue to suffer.”

Question 9

Circular Reasoning

Answer 9

Description: The conclusion is just a restatement of a premise rather than providing a new reason.

Example: “Reading is enjoyable because it’s fun.”

Pretty Rare

Question 10

Equivocation

Answer 10

Description: Uses a word or phrase with multiple meanings inconsistently in the argument.

Example: “A feather is light. Therefore, it cannot be dark.”

Question 11

Part-to-Whole (or Whole-to-Part) Flaw

Answer 11

Description: Assumes that what is true of the parts must be true of the whole, or vice versa.

Example: “Each part of the machine is lightweight, so the entire machine must be lightweight.”
or
“The entire machine is lightweight, so each part of the machine must be lightweight”

Question 12

False Analogy

Answer 12

Description: Assumes that because two things are similar in one way, they must be similar in other ways.

Example: “Just like cars need tune-ups, our economy needs stimulus packages.”

Question 13

Unrepresentative Sample

Answer 13

Description: Bases a conclusion on a sample that does not represent the larger group.

Example: “All of my friends enjoy classical music, so the general public must love it too.”

Question 14

Biased Sampling

Answer 14

Description: Draws conclusions from a sample that is not randomly selected, making it biased.

Example: “A survey of wealthy patrons at a luxury restaurant shows that most people are in favor of tax cuts for the rich.”

Question 15

Survey Errors

Answer 15

Description: Relies on survey data but fails to consider issues like biased sampling, poorly phrased questions, or small sample size.

Example: “A poll showed that 90% of respondents prefer product X, but it turns out only 10 people were surveyed.”

Question 16

Composition and Division Errors

Answer 16

Description: Incorrectly assumes that what’s true of the parts is true of the whole, or what’s true of the whole is true of the parts.

Example: “Since every ingredient in this dish is delicious, the dish must be delicious.”

Same as Part to Whole/Whole to Part

Question 17

Relative vs. Absolute

Answer 17

Description: Confuses relative statements (comparisons) with absolute statements (generalizations).

Example: “This car is cheaper than the others, so it must be cheap.”

Question 18

Ad Hominem (Attacking the Person)

Answer 18

Description: Attacks the person making the argument rather than the argument itself.

Example: “You shouldn’t listen to her argument on climate change; she’s not even a scientist.”

Question 19

Straw Man

Answer 19

Description: Misrepresents an opponent’s argument to make it easier to attack.

Example: “My opponent wants to cut the defense budget, which means he wants to leave our country defenseless.”

Question 20

Temporal Flaws

Answer 20

Description: Assumes that because something was true in the past, it must be true in the future, or vice versa.

Example: “This stock has been rising for months, so it will continue to rise.”

Question 21

Self-Contradiction

Answer 21

Description: The argument contains statements that contradict each other.

Example: “You can’t trust people who wear glasses, but you can trust my friend who wears glasses.”

Question 22

Absence of Evidence

Answer 22

Description: Concludes something is true because there is no evidence proving it false or vice versa.

Example: “No one has proven aliens don’t exist, so they must be real.”

Question 23

Percent vs. Amount

Answer 23

Description: Confuses percentages with absolute quantities, ignoring the total size of the population.

Example: “Company A had a 10% growth in sales, while Company B had a 5% growth. Therefore, Company A’s total sales must be higher.”

Company A originally did 100 sales now with a 10% growth they do 110 sales. Company B does 300 sales and with a 5% growth they now do 315, Therefore, company B’s total sales is higher.

Question 24

Scope Shift

Answer 24

Description: The argument’s premise discusses one thing, but the conclusion shifts to a different, unconnected topic.

Example: “Pollution in cities is decreasing, so rural areas must also have cleaner air.”

Question 25

Hasty Generalization

Answer 25

Description: Draws a broad conclusion from limited data or few instances.

Example: “After meeting two friendly people from Boston, I concluded that everyone from Boston is friendly.”

Same as overgeneralization?

Question 26

Confusing Necessary and Sufficient Conditions

Answer 26

Description: Assumes a condition is necessary when it’s only sufficient, or vice versa.

Example: “To become a lawyer, one must go to law school. Therefore, everyone who goes to law school becomes a lawyer.”

Same as Conditional Logic Flaw

Question 27

Know flaw

Answer 27

Example: “John will be promoted only if, Jackie retires. John knows that Jackie will retire. Thus, John knows he will be promoted”

We do not know if John knows the condition. Jackie might have told John she was retiring, but we do not know if the company has told john he will get promoted only if Jackie retires. John only know that Jackie is Retiring.

(This example also includes sufficient and Necessary Flaw)

Question 28

Is-Ought (AKA the “prescriptive” or “normative” flaw)

Answer 28

Descriptive Premises: The argument starts by stating facts about how things are.
Prescriptive Conclusion: The argument then concludes with how things should be or what one ought to do.
Lack of Justification: The argument doesn’t provide a rationale for why what is should dictate what ought to be.

Argument: “People have always eaten meat, so there’s nothing wrong with eating meat.”
Flaw: This reasoning assumes that because people have traditionally eaten meat (a descriptive fact), eating meat is therefore morally acceptable (a prescriptive claim). However, the argument fails to explain why the tradition of eating meat justifies its moral acceptability.

Question 29

Routinely to Never

Answer 29

Can’t go from, “something bad ROUTINELY happens which causes x, y, and z bad consequences. Thus we should NEVER let that something bad happen.”

Because what happens if the something bad happens sometimes? Will it lead to the same consequences? we don’t know.

How to correct: “something bad SOMETIMES happens which causes x, y, and z bad consequences. Thus we should NEVER let that something bad happen.”

Sometimes = 1/10 or 10% at its lowest