CH 8: Formal & Language Fallacies - Lecture Review

These flashcards review key concepts and terms related to formal and language fallacies covered in the lecture.

What are the three formal fallacies mentioned in the lecture?

Affirming the Consequent, Denying the Antecedent, Undistributed Middle.

What is Affirming the Consequent?

An invalid form of argument: If P, then Q. Q. Therefore, P.

• incorrectly assuming the cause is true because the effect is true

Provide an example of Affirming the Consequent.

If Jane is a member of a sorority, then she is female. Jane is female. Therefore, Jane is a member of a sorority.

What is Denying the Antecedent?

An invalid form of argument: If P, then Q. Not-P, Therefore Not-Q.

• incorrectly assuming that if the cause is wrong, the effect is also false

Provide an example of Denying the Antecedent.

If Howard passed the final, then he passed the course. Howard did not pass the final. Therefore, Howard did not pass the course.

What is the Undistributed Middle fallacy?

Assuming that two things related to a third thing are related to each other.

Provide an example of the Undistributed Middle fallacy.

All cats are mammals. All dogs are mammals. Therefore, all cats are dogs.

What is the fallacy of Equivocation?

Occurs when a word is used ambiguously in different senses within the same argument.

Provide an example of Equivocation.

All banks are alongside rivers; the place where I keep my money is a bank. Therefore, the place where I keep my money is alongside a river.

What is Amphiboly?

Occurs when the structure of a sentence creates ambiguity.

Provide an example of Amphiboly.

If you want to take the motor out of the car, I’ll sell it to you cheap. The pronoun ‘it’ may refer to the car or to the motor.

What is the Composition fallacy?

Assuming what is true of individual parts is true for the whole.

Provide an example of the Composition fallacy.

This building is made from rectangular bricks; therefore, it must be rectangular.

What is Division fallacy?

Assuming what is true of a whole must be true of its individual parts.

Provide an example of the Division fallacy.

This building is circular; therefore, it must be made from circular bricks.

What is the Gambler's Fallacy?

The false belief that past events affect the probabilities of independent events.

Provide an example of the Gambler's Fallacy.

Believing that after several flips of tails, the next flip must be heads.

What does it mean to overlook prior probabilities?

Failing to consider the true likelihood of an event outside of any other influences.

What is a false positive in the context of probability?

An incorrect conclusion that indicates the presence of something when it is not there.