Question 1

A valid deductive argument can't have inconsistent premises.

Accepted Answer

A valid deductive argument can have inconsistent premises and still be valid if the logical structure guarantees that the conclusion follows necessarily from the premises. Validity concerns the form of the argument rather than the truth of its premises.

Question 2

The following argument is valid: "We live on Mars; therefore, we live on Mars."

Accepted Answer

The argument is valid because it directly restates the premise as the conclusion, ensuring logical consistency.

Question 3

The following statement is a fallacious argument: "I haven't quite made up my mind."

Accepted Answer

The statement "I haven't quite made up my mind." expresses indecision or uncertainty, rather than presenting an argument, fallacious or otherwise.

Question 4

The following statement is an example of false dilemma: "Either it is raining or it's not."

Accepted Answer

The statement "Either it is raining or it's not." is an example of a tautology, representing a basic law of logic (the law of excluded middle), not a false dilemma. A false dilemma involves presenting two options as the only possibilities when in fact more options exist.

Question 5

A "valid argument" concerns the
A) truth of the premises.
B) the connection between the premises and conclusion.
C) the persuasiveness of the argument.
D) the truth of the premises.

Accepted Answer

A valid argument is one where if the premises are true, the conclusion must also be true. It concerns the logical structure and the connection between the premises and the conclusion, not the actual truth of the premises or the persuasiveness of the argument.

Question 6

"Either it's going to rain tomorrow or it isn't." This argument is best symbolized as
A) p v ∼ q
B) ∼ p v q.
C) p ⊃ q.
D) p v ∼ p.

Accepted Answer

This statement is an example of the law of excluded middle, which states that a proposition must either be true or its negation must be true. In this case, "p" represents "it's going to rain tomorrow," and "∼p" represents "it is not going to rain tomorrow." Therefore, "p v ∼p" correctly symbolizes the statement, indicating that either it will rain tomorrow or it will not, with no third option possible.

Question 7

With a valid deductive argument we know that
A) the premises are true.
B) if the conclusion is true, the premises are probably true.
C) the conclusion is true.
D) None of the above

Accepted Answer

A valid deductive argument does not guarantee the truth of its premises or conclusion; it only ensures that if the premises are true, then the conclusion must be true. Therefore, none of the provided options accurately describe what we know from a valid deductive argument alone.

Question 8

If this is 2094, then it is the twenty-first century
It is 2094
--------------
It is the twenty-first century
The above argument is:
A) valid.
B) sound.
C) invalid.
D) None of the above

Accepted Answer

The argument is valid because the conclusion logically follows from the premise. If it is indeed 2094, according to our calendar system, it would be the twenty-first century.

Question 9

The valid argument modus tollens is symbolized as:
A) If p, then q; p; therefore q.
B) If p, then q; not q; therefore not p.
C) Either p or q; not p; therefore q.
D) None of the above

Accepted Answer

Modus tollens is a form of logical argument where the premise includes a conditional statement (if p, then q) and the denial of the consequent (not q), leading to the conclusion that denies the antecedent (not p).

Question 10

The valid argument hypothetical syllogism is symbolized as:
A) If p, then q; p; therefore q.
B) If p, then q; not q; therefore not p.
C) Either p or q; not p; therefore q.
D) None of the above

Accepted Answer

Hypothetical syllogism is a valid form of argument that follows the structure: If p, then q; if q, then r; therefore, if p, then r. None of the given options match this structure.

Question 11

Either moral questions are like scientific questions or they're like questions of taste.
It's not the case that moral questions are like scientific questions.
--------------
Moral questions are like questions of taste.
The above argument is an example of:
A) modus ponens.
B) disjunctive syllogism.
C) hypothetical syllogism.
D) modus tollens.

Accepted Answer

The argument presents two options, excludes one, and concludes that the other must be true, which is the structure of a disjunctive syllogism.

Question 12

If we have free will, then our choices aren't caused.
If our choices aren't caused, then our choices happen by chance.
--------------
If we have free will, then our choices happen by chance.
The above argument is an example of
A) modus ponens.
B) disjunctive syllogism.
C) hypothetical syllogism.
D) modus tollens.

Accepted Answer

This argument is an example of a hypothetical syllogism, which involves three statements: two premises that lead logically to a conclusion. The structure is "If A, then B; If B, then C; therefore, if A, then C."

Question 13

If p, then q
Not p
--------------
Not q
The above argument is an example of the fallacy of
A) affirming the antecedent.
B) denying the antecedent.
C) affirming the consequent.
D) denying the consequent.

Accepted Answer

The argument commits the fallacy of denying the antecedent, which incorrectly assumes that if the antecedent (p) is false, then the consequent (q) must also be false. This is a logical fallacy because the truth of the consequent does not necessarily depend on the truth of the antecedent in this way.

Question 14

Reasoning that someone is guilty "beyond a reasonable doubt" would be an example of what type of reasoning?
A) Deductive reasoning
B) Inductive reasoning
C) Circular reasoning
D) None of the above

Accepted Answer

Inductive reasoning involves making generalizations based on specific observations or evidence. The concept of proving guilt "beyond a reasonable doubt" in a legal context relies on the accumulation of evidence that, when considered together, strongly supports the conclusion of guilt. This process aligns with inductive reasoning, where conclusions are drawn from the evidence at hand, even if absolute certainty is not possible.

Question 15

"Don't believe what Professor Ingram says in his physics class. I hear he cheats on his wife." This would be an example of
A) circular reasoning.
B) argument from authority.
C) ad hominem argument.
D) appeal to popular opinion.

Accepted Answer

This is an ad hominem argument because it attacks the character of Professor Ingram (his alleged infidelity) rather than addressing the validity of his statements or teachings in physics class.

Question 16

"People seem to like what John has to say. I'd believe him if I were you." This statement involves what fallacy?
A) Circular reasoning
B) Appeal to popular opinion
C) Ad hominem argument
D) Begging the question

Accepted Answer

The statement commits the fallacy of appeal to popular opinion by suggesting that something should be believed or accepted simply because it is popular or widely accepted by others.

Question 17

"There can't be global warming. Just look at how cold it was last week." This statement involves a(n)
A) appeal to ignorance.
B) hasty conclusion.
C) inconsistency.
D) slippery slope.

Accepted Answer

This statement is an example of a hasty conclusion because it draws a broad conclusion about global warming based on a very limited and specific piece of evidence (a single cold week), without considering the broader and more complex evidence about climate patterns and trends.

Question 18

"We'll get him a fair trial and then hang him." This statement would likely be an example of the fallacy of
A) provincialism.
B) inconsistency.
C) appeal to force.
D) appeal to authority.

Accepted Answer

The statement "We'll get him a fair trial and then hang him" is an example of inconsistency because it contradicts itself by suggesting a fair trial will be given, yet the outcome (hanging) is predetermined regardless of the trial's fairness or outcome.

Question 19

"Get your head on straight. You're going to get in trouble with your neighbors believing things like that." This statement would likely be an example of the fallacy of
A) inconsistency.
B) appeal force.
C) false dilemma.
D) slippery slope.

Accepted Answer

The statement is an example of the appeal to force fallacy, where it suggests that the person will face negative consequences (trouble with neighbors) for their beliefs, rather than addressing the validity of the beliefs themselves.

Question 20

"Let the government into our lives, and they will take over everything." This statement would likely be an example of the fallacy of
A) inconsistency.
B) appeal to force.
C) false dilemma.
D) slippery slope.

Accepted Answer

This statement is an example of a slippery slope fallacy, which occurs when an argument suggests that a relatively small first step will lead to a chain of related events culminating in some significant (usually negative) effect, without providing sufficient evidence to support the inevitable chain of events.

Quiz 1: Logic

A valid deductive argument can't have inconsistent premises.

The following argument is valid: "We live on Mars; therefore, we live on Mars."

The following statement is a fallacious argument: "I haven't quite made up my mind."

The following statement is an example of false dilemma: "Either it is raining or it's not."

A "valid argument" concerns the

"Either it's going to rain tomorrow or it isn't." This argument is best symbolized as

With a valid deductive argument we know that

If this is 2094, then it is the twenty-first century It is 2094 -------------- It is the twenty-first century The above argument is:

The valid argument modus tollens is symbolized as:

The valid argument hypothetical syllogism is symbolized as:

Either moral questions are like scientific questions or they're like questions of taste. It's not the case that moral questions are like scientific questions. -------------- Moral questions are like questions of taste. The above argument is an example of:

If we have free will, then our choices aren't caused. If our choices aren't caused, then our choices happen by chance. -------------- If we have free will, then our choices happen by chance. The above argument is an example of

If p, then q Not p -------------- Not q The above argument is an example of the fallacy of

Reasoning that someone is guilty "beyond a reasonable doubt" would be an example of what type of reasoning?

"Don't believe what Professor Ingram says in his physics class. I hear he cheats on his wife." This would be an example of

"People seem to like what John has to say. I'd believe him if I were you." This statement involves what fallacy?

"There can't be global warming. Just look at how cold it was last week." This statement involves a(n)

"We'll get him a fair trial and then hang him." This statement would likely be an example of the fallacy of

"Get your head on straight. You're going to get in trouble with your neighbors believing things like that." This statement would likely be an example of the fallacy of

"Let the government into our lives, and they will take over everything." This statement would likely be an example of the fallacy of