Free Practice Quiz Question List

4/9 4. Validity and Soundness Online Quiz Questions

Use this free practice quiz with 20 questions to review 4/9 4. Validity and Soundness, test your knowledge, and prepare for your next test or exam.

20 questions

Choose one

1 point

Which condition defines deductive validity?

A
The conclusion is actually true.
B
The premises cannot all be true while the conclusion is false.
C
All of the premises are actually true.
D
The argument uses familiar subject matter.

Choose one

1 point

Which argument form is modus ponens?

A
If P, then Q; Q; therefore P
B
If P, then Q; not P; therefore not Q
C
If P, then Q; P; therefore Q
D
If P, then Q; not Q; therefore not P

Choose one

1 point

Consider this argument: All reptiles are mammals. Snakes are reptiles. Therefore, snakes are mammals. How should the argument be classified?

A
The argument is valid but unsound.
B
The argument is invalid but sound.
C
The argument is both invalid and sound.
D
The argument is sound because its conclusion follows.

Written response

1 point

What is the name of the valid argument form with this structure: If P, then Q; P; therefore Q?

Written response

1 point

What term describes an inductive argument whose premises provide substantial support for its conclusion, without guaranteeing it?

Fill in the blank

1 point

A deductive argument is sound only if it is and all of its premises are actually .

Fill in the blank

1 point

To show that a deductive argument is invalid, one must find a possible case in which all the premises are true and the conclusion is ; the argument's resulting status is .

Open ended

1 point

Explain why this argument form is invalid: If P, then Q; Q; therefore P. Include a counterexample or alternative explanation showing how the premises can be true while the conclusion is false.

Choose one

1 point

When using a truth table to test an argument's validity, what should you do after identifying the rows in which all premises are true?

A
Check whether the conclusion is true in at least one row, regardless of the premises.
B
Check every row in which all premises are true and see whether the conclusion is also true.
C
Check whether each premise is true in the real world.
D
Check whether the conclusion is more probable than the premises.

Choose one

1 point

A deductive argument has premises that are all true, but there is a possible case in which its conclusion is false. How should the argument be classified?

A
The argument is valid because the conclusion happens to be true.
B
The argument is invalid because the premises can be true while the conclusion is false.
C
The argument is sound because its premises are true.
D
The argument is inductive because its conclusion is false.

Choose one

1 point

An argument has a valid logical form, but one of its premises is false. What is the correct evaluation?

A
It is sound because validity alone is sufficient.
B
It is invalid because one premise is false.
C
It is unsound because a sound argument must be valid and have only true premises.
D
It is inductively strong because its conclusion follows from its premises.

Choose one

1 point

A researcher argues that if several stated premises are true, a particular conclusion must be true. What kind of reasoning is the researcher presenting?

A
Deductive reasoning, because the premises are intended to guarantee the conclusion.
B
Inductive reasoning, because every conclusion based on evidence is inductive.
C
Deductive reasoning, because deductive conclusions are always actually true.
D
Inductive reasoning, because inductive conclusions are guaranteed when the evidence is strong.

Choose one

1 point

When using a truth table to test a deductive argument, which procedure correctly determines whether the argument is valid?

A
Check whether the conclusion is true in at least one row.
B
Check whether every proposition is true in every row.
C
Check only the row in which the conclusion is false.
D
Check whether the conclusion is true in every row where all premises are true.

True or false

1 point

True or false: A deductively valid argument can have a false premise.

A
True
B
False

Written response

1 point

What is the name of the valid argument form with this structure: If P, then Q. P. Therefore, Q?

Written response

1 point

A person observes that the last 20 buses on a route arrived late and concludes that the next bus will probably arrive late. What type of reasoning is being used?

Choose all

1 point

Consider this argument: If the alarm is set, the light flashes. The alarm is not set. Therefore, the light does not flash. Select all statements that correctly evaluate the argument.

A
The argument is invalid.
B
The argument commits denying the antecedent.
C
The light could flash even when the alarm is not set.
D
The conclusion is guaranteed because the first premise is a conditional.

True or false

1 point

True or false: For the argument form If $P$ , then $Q$ ; $Q$ ; therefore, $P$ , one specific case in which $P$ is false and $Q$ is true is enough to show that the form is invalid.

A
True
B
False

True or false

1 point

True or false: If a proposed counterexample has true premises and a true conclusion, it still establishes that the deductive argument form is invalid.

A
True
B
False

Choose all

1 point

Consider this argument: “Every certified guide completed safety training. Lena is a certified guide. Therefore, Lena completed safety training.” Select all statements that correctly identify the roles of the statements in the argument.

A
“Every certified guide completed safety training” is a premise.
B
“Lena is a certified guide” is a premise.
C
“Lena completed safety training” is the conclusion.
D
“Every certified guide completed safety training” is the conclusion.
E
The argument has no conclusion.