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Logical fallacies

A fallacy is the use of faulty reasoning that undermines an argument's validity.

Example 1.

Which fallacy applies to the following example?

"The movie is going to be boring if Steve directed it."

(A) Ad hominem, (B) Begging the question, (C) Post Hoc, Ergo Propter Hoc

Solution: Ad hominem. Attacking the person rather than attacking the substance of the argument. Concepts are not evaluated on their own merits, and are rejected based on the source.

Example 2

Which fallacy applies to the following example?

"If aliens didn't make the crop circles, who did?"

(A) Hasty generalization, (B) Begging the question, (C) Post Hoc, Ergo Propter Hoc

Solution: Begging the question(form of circular reasoning). This fallacy is associated with circular reasoning; it's usually the case that the premise and the conclusion are closely associated.

1. Which fallacy applies to the following example?

"There was a flash of lighting before the music stopped. The storm must have intefered with the sound equipment."

(A) Hasty generalization

(B) Bandwagon

(C) Post Hoc, Ergo Propter Hoc

Post Hoc, Ergo Propter Hoc

In latin this translates to 'after this, therfore because of this", and referes to arguments that something occured solely because of something else which occurred before it.



2. Which fallacy applies to the following example?

"All odd numbers between 3 and 13 are prime numbers. 15 must also be a prime number."

(A) Hasty generalization

(B) Bandwagon

(C) Ad hominem

Hasty generalization

This fallacy results from making assumptions that are based on an insufficient sample size. This results in broad conclusions that are lacking in sufficient evidence and can create stereotypes.


3. Which fallacy applies to the following example?

"Everyone is going to the movies, there must be some good shows."

(A) Begging the question

(B) Bandwagon

(C) Post Hoc, Ergo Propter Hoc

Bandwagon fallacy

Popular opinion is not able to confirm a proposition as true or false.


4. Which fallacy applies to the following example?

"Just ignore his theory about the science experiment. He got a D in mechanics."

(A) Hasty generalization

(B) Bandwagon

(C) Ad hominem

Ad hominem

Attacking the person rather than attacking the substance of the argument. Concepts are not evaluated on their own merits, and are rejected based on the source.


5. Which fallacy applies to the following example?

"If I can't fix it, then who can?"

(A) Hasty generalization

(B) Bandwagon

(C) Begging the question

Begging the question

This fallacy is associated with circular reasoning; it's usually the case that the premise and the conclusion are closely associated.