# Chapter 3 Philosophy Study Guide

disjunctive syllogism

Vocab Either p or q Not p Therefore q

disjunctive syllogism

Vocab Either we light the fire or we will freeze We will not light the fire Therefore, we will freeze

modus ponens

Vocab If Spot barks, a burglar is in the house Spot is barking Therefore, a burglar is in the house

deductive and inductive

Arguments come in what two forms?

modus ponens, modus tollens, hypothetical syllogism, disjunctive syllogism

Four valid forms

invalid argument

Vocab a deductive argument that fails to provide conclusive support for its conclusion

disjunctive syllogism

A valid argument form: Either p or q Not p Therefore, q

all A are B

Sentence A "universal affirmative" is a statement of the form...

true premises and a false conclusion

Sentence A deductively valid argument cannot have:

If P then Q; P; Therefore, Q

Sentence Modus Ponens has this argument pattern:. If P, then Q

search for credible premise

Sentence The first step in investigating possible implicit (unstated) premises is to:

if P, then Q

Sentence The form of a Conditional Statement is: P, Q

if p, then q; q; therefore, p

Sentence The invalid argument form known as affirming the consequent has this pattern: if p, then q

if all a are b, then q

Sentence Which of the following is a variation on a Conditional Statement? A and B

if p, then q; not p; therefore, not q

Sentence The invalid argument form known as denying the antecedent has this pattern: If p, then q

true

True or False A "sound" argument cannot have a false conclusion; all sound arguments have true conclusions.

true

True or False A valid argument could have false premises and a false conclusion.

true

True or False An invalid argument could have true premises and a true conclusion

false

True or False Because of the guarantee of truth in the conclusion, inductively strong arguments are said to be truth-preserving.

true

True or False Only a small portion of a passage may contain statements that serve as the premises and conclusion.

true

True or False The argument form Modus Tollens is always valid

false

True or False The first statement in a conditional premise is known as the consequent.

false

True or False The following argument is valid: "If the governor does a good job, then the economy will improve. The economy has improved. Therefore, the governor did a good job."

affirming the consequent, denying the antecedent

Two invalid forms

truth-preserving

Vocab A characteristic of a valid deductive argument in which the logical structure guarantees the truth of the conclusion if the premises are true

syllogism

Vocab A deductive argument made up of three statements- two premises and a conclusion

modus tollens(denying the consequent)

Vocab A valid argument form: If p, then q Not q Therefore, not p

modus ponens (affirming the antecedent)

Vocab A valid argument form: If p, then q p Therefore, q

hypothetical syllogism

Vocab A valid argument made up of three hypothetical, or conditional, statements If p, then q If p, then r Therefore, if p, then r

deductive

Vocab An argument intended to provide logically conclusive support its conclusion is:

strong

Vocab An inductive argument that succeeds in providing probable, but not conclusive, logical support for its conclusion is said to be:

denying the antecedent

Vocab An invalid form: If p, then q Not p Therefore, not q

affirming the consequent

Vocab An invalid form: If p, then q q Therefore, p

hypothetical syllogism

Vocab If Ajax steals the money, he will go to jail If Ajax goes to jail, his family will suffer Therefore, if Ajax steals the money, his family will suffer

modus tollens

Vocab If it's raining, the park is closed The park is not closed Therefore, it's not raining

hypothetical syllogism

Vocab If p, then q If q, then r Therefore, if p, then r

denying the antecedent

Vocab If p, then q Not p Therefore, not q

modus tollens

Vocab If p, then q not q Therefore, not p

modus ponens

Vocab If p, then q p Therefore q

affirming the consequent

Vocab If p, then q q Therefore, p

affirming the consequent

Vocab If the cat is on the mat, she is asleep She is asleep Therefore, she is on the mat

denying the antecedent

Vocab If the cat is on the mat, she is asleep She is not on the mat Therefore, she is not asleep

disjunctive syllogism

Vocab The following argument form is a variation of which logical pattern? Either P, or Q, or R, or S. Not P and not S. Therefore, Q or R.

modus tollens

Vocab The following argument form is a variation of which logical pattern? If All A are B, then Q. Not Q. Therefore, not all A are B.

valid argument

Vocab a deductive argument that succeeds in providing conclusive support for its conclusion

sound argument

Vocab a good argument which gives you good reasons for accepting its conclusion

cogent argument

Vocab a strong inductive argument with all true premises

conditional statement

Vocab an "if-then" statement, it consists of the antecedent(if) and the consequent(then)

inductive

Vocab argument intended to provide probable support for its conclusion (not conclusive)

weak argument

Vocab inductive argument that fails to provide probable, logical support for its conclusion

strong argument

Vocab inductive argument that succeeds in providing probable, logical support for its conclusion

antecedent

Vocab the first part of the conditional statement (if p, then q)

consequent

Vocab the part of a conditional statement( if p, then q) introduced by the word "then"

No

Yes or No Can a sound argument have a false conclusion?

Yes

Yes or No Can a valid argument have a false conclusion?

Yes

Yes or No Can a valid argument have all false premises?

No

Yes or No Can an invalid argument have true premises and conclusion?

No

Yes or No Can you have a valid argument with T premises and F conclusions?