Argument Flaw Identification Flashcards

Advertiser: Nine out of ten dentists recommend Bright Smile toothpaste. Therefore, Bright Smile is the best toothpaste available. What is the flaw?

Answer: It treats a popular endorsement as proof of objective superiority

Professional endorsement reflects preference or recommendation, not an objective measurement of superiority over all other options.

Politician: If we allow same-sex marriage, soon people will want to marry animals. We must not allow same-sex marriage. What flaw does this illustrate?

Answer: Slippery slope — assuming one change inevitably leads to an extreme outcome

The argument claims one policy change will inevitably lead to extreme outcomes without providing evidence for each causal link.

Executive: Our company has been profitable every year that Jenkins has been CEO. Jenkins must be the reason for our profitability. What is the flaw?

Answer: Post hoc fallacy — assuming temporal association implies causation

Profitability occurring during Jenkins's tenure does not establish that Jenkins caused the profitability.

Critic: You argue that we should fund the arts, but you yourself can't even draw a straight line. Your opinion is worthless. What flaw is present?

Answer: Ad hominem — dismissing a claim based on the person's irrelevant characteristics

The ability to draw has no bearing on whether arts funding arguments are logically sound.

Investor: Either this company will become profitable or it will go bankrupt. It has not gone bankrupt. Therefore, it must now be profitable. What is the flaw?

Answer: False dichotomy — ignoring intermediate states like break-even or stagnation

A company can exist in states between profitability and bankruptcy, such as operating at break-even or surviving on loans.

Scientist: Our lab tests showed that the drug worked on mice. Therefore, it will work on humans. What is the primary flaw?

Answer: It draws an inference from a source that may not be analogous to humans

The physiological differences between mice and humans make generalizing results across species an unreliable inference.

Parent: My son says he didn't steal the cookie, so he didn't steal it. Which reasoning flaw is illustrated?

Answer: Circular reasoning — using the claim itself as the only evidence for the claim

The argument uses the son's denial as both the premise and the conclusion, providing no independent evidence.