Logic Exam 1 Flashcards
Identify the three central laws of logic
Law of the Excluded Middle: There is no middle ground to true or false.
Law of Identity: If a statement is true, it is true.
Law of Non-Contradiction: A statement cannot be both true and false (in the same way, at the same time).
Know the differences between deductive and inductive arguments
Deductive: a specific conclusion is reached from general statements/premises (top-down)
Inductive: a general conclusion is reached from specific statements/premises. (bottom-up)
Be able to identify premises and conclusions
Conclusion: non-contradicting, indicative statements (statements which must be either true or false) of what you are seeking to prove (60)
Premises: non-contradicting, indicative statements of the reasons for coming to that conclusion. (60)
Identify: modus ponens (way of affirming)
If P, then Q.
P.
Therefore Q.
Identify: modus tollens (way of denying)
If P, then Q.
Not Q.
Therefore not P.
Identify: hypothetical syllogism
syllogisms with hypotheticals/if-thens, therefore. A valid argument form which is a syllogism having a conditional statement for one or both of its premises.
Valid examples: modus ponens, modus tollens
Invalid examples: affirming the consequent, denying the antecedent
Identify: ad hominem
Attacking or praising the people who make an argument rather than discussing the argument itself. (Argument to the Man)
Identify: ad populum
Using an appeal to popular assent/the masses, often by arousing the feelings and enthusiasm of the multitude as a mere multitude rather than building an argument. (Argument to the People)
Identify: affirming the consequent
If P, then Q.
Q.
Therefore P.
Identify: denying the antecedent
If P, then Q.
Not P.
Therefore not Q
Identify: Bulverism (genetic fallacy)
the claim that an idea, product, or person is assumed to be wrong, then the origin of the claimant’s claim is attacked
Identify: begging the question (Circular Reasoning)
Writers assume as evidence for their argument the very conclusion they are attempting to prove. Assuming what needs proving.
Idenify: post hoc (after this)
the assumption that because one event is preceded by the second event, it must mean that the first event must have caused the second event. (After this, therefore because of this). where chronological priority is the only real reason given for the assumed casual relationship.
Identify: either/or fallacy
he assumption that there are only two choices or possible outcomes when actually there are several. (Excluded Middle)
Identify: strawman
where a speaker sets up his opposition in an unfair way (not held by the opposition), so that it is easy to take down.
Identify: ipse dixit (he has said it himself)
an illegitimate appeal made to authority
Identify: Ad baculum
an appeal to “the stick.” (appealing to forceful acceptance)
Identify: Tu quoque
A “you too” argument
Identify: Ad ignoratium
appeals to lack of information, an argument from silence
Identify: Chronological snobbery
argument rejected from something’s newness or oldness
Identify: Fallacy of equivocation
when one of the terms in the argument/mid-argument has more than one meaning, with a pretense that such has not been done.
Identify: Fallacy of accent
a sentence’s shift in meaning due to simple differentiation in italics/emphasis
Identify: Fallacy of selective arrangement
statements made to invite conclusions less than accurate
Identify: Fallacy of amphiboly
where a sentence, taken as a whole, is ambiguous.
Identify: Fallacy of composition
when someone thinks that whatever is true of parts must be true of the whole.
Identify: Fallacy of division
the opposite of the previous fallacy; anything that is true of the whole must be true of its parts.
Identify: Apriorism
a hasty generalization
