Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

PHIL 220 > Course Content > Flashcards

Course Content Flashcards

1
Q

______ is expressed by a declarative sentence

A

Proposition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

“it’s going to rain tomorrow”

Is this a proposition?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

“I like bacon”

Is this a proposition?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

“close the window because I’m cold”

Is this a proposition?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

“Will this be on the exam?”

Is this a proposition?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

“the Italian flag has 3 colours”

Is this a proposition?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Logic is in part the study of _______

A

Arguments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

All arguments have a _________

A

Conclusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

“Don’t touch the wire, because it’s hot.”

Is this an argument?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

An ______ has to be able to be true or false

A

Argument

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

In a formal argument, what format is followed

A

-First sentences are the premises.

-last sentence is the conclusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Each sentence in an argument must be a _________

A

Proposition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are some common argument conclusion indicators?

A

So, therefore, etc.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Validity is a ______ of an argument

A

Property

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

An argument is valid if and only if _________________.

A

it is impossible for the premises to be true while at the same time the conclusion is false.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

“If all insects are tasty, then scorpions are tasty.”

Is this a valid argument?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

“Only a secret Muslim would bow to the Saudi king. Obama bowed to the Saudi king. Therefore, Obama is a secret Muslim.”

Is this a valid argument?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Jonathan has a cat and Jonathan does not have a cat. Therefore, tomato-based dishes are best paired with wines from colder regions.

Is this a valid argument?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Arguments with impossible premises are always ______

A

Valid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Why are arguments with impossible premises always valid?

A

Because the premises CAN’T be true, there is no possible way to make the premises true while the conclusion false.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Does the premise have to be intuitively relevant to the conclusion for an argument to be technically valid?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

An argument is sound if and only if (2)

A

1) it is valid
2) all of the premises are true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Sound arguments always have ____ conclusions

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

“Only a secret Muslim would bow to the Saudi king. Obama bowed to the Saudi king. Therefore, Obama is a secret Muslim.”

Is this argument sound?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

“Opera singers are sexy. Therefore, opera singers are sexy.”

Is this argument sound?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Soundness assumes all propositions are _______

A

True or false

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Valid argument form example (Modus Ponens)

A

If P, then Q.
P.
So, Q.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

A form is valid iff

A

any argument with that form must be valid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

If P, then Q.
Q.
So, R.

Is this a valid argument form

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

An argument form is invalid when

A

It fails to guarantee that the argument will be valid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Can arguments be valid with an invalid argument form?

A

Yes, but the form does not explain why it is valid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

If P, then Q. So R

P: I have a pet dog.
Q: I have a pet cat.
R: I have at least one pet.

Is this a valid argument?
Is the form of the argument valid?

A

The argument is valid because the conclusion can’t be false while the premises are true.

The form is invalid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Propositional connectives (6)

A

Conjunction
Disjunction
Recursion
Conditional
Biconditional
Negation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

for any two sentences you can make a new sentence that is their _____

A

Conjunction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

P & Q is a

A

Conjunction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

In P & Q, P and Q are each

A

Conjuncts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

If a conjunction sentence is true, ______ are true

A

Both conjuncts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Do conjunctions always have to be represented using “and”

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

“France is over-rated, but susan wants to go there anyway.”

Is this a conjunction?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

“Dmitri loves to sing and his hair is white.”

Is this a conjunction?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

“Simon and Alex are going to hook up tonight.”

Is this a conjunction?

A

No, because the normal way to read it is that they are going to hook up together, which is one proposition.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

“One false move and I’ll shoot.”

Is this a conjunction?

A

No, it’s a conditional

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Is this a conjunction?

“John is afraid that Eliza and Delia will come to the party.”

A

No

Could very well mean that he doesn’t want them to come together, but is okay if they come alone, meaning this expresses one proposition.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

A disjunction means that

A

One of the two disjuncts is true, or both

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Disjunctions are true any time ____________

A

at least one disjunct is true.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

P V Q represents

A

A disjunction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Making complex sentences by conjoining or disjoining non-atomic sentences is called

A

Recursion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Is there a limit to the length and complexity of a recursive sentence?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

If P, then Q is a _______

A

Conditional

50
Q

P ⊃ Q means

A

If P, then Q

51
Q

“If I don’t eat soon, then I will be sad.”

Is this a conditional?

A

Yes

52
Q

“If he is going to the beach, then it is sunny”

Is this a conditional?

A

Yes

53
Q

Ways to write conditionals (4)

A

P ⊃ Q
P, Q
Q if P
P only if Q

54
Q

Conditional that works in both directions is called

A

Biconditional

55
Q

If and only if / iff is a

A

biconditional

56
Q

P ≡ Q is a

A

Biconditional

57
Q

Ways to represent a biconditional (3)

A

P ≡ Q
P iff Q
P if and only if Q

58
Q

Every sentence has another sentence that is its ______

A

Negation

59
Q

the negation of P is

A

¬P

60
Q

P is the _____ of ¬P

A

Negand

61
Q

“I’m not wearing a red tie”

Is this a negation?

A

Yes

62
Q

(P v Q) & ¬ (P &Q)

this means

A

“one or the other, but not both”

63
Q

T or F:

All arguments with true premises and true conclusions are sound.

A

False

64
Q

T or F:

Only valid arguments are sound.

A

True

65
Q

T or F:

If an argument to the conclusion A is sound, then an argument to the conclusion not A is not sound.

A

True

66
Q

T or F

All arguments with at least one impossible premise are valid.

A

True

67
Q

T or F:

All invalid arguments are instances of invalid argument forms.

A

True

68
Q

No invalid arguments have impossible premises.

A

True

69
Q

Is the following valid and/or sound?

PHIL 220 is a history class. Therefore, PHIL 220 is a history class or a linguistics class.

A

Valid, but not sound

70
Q

Is the following valid and/or sound?

If it rained yesterday, it means that Beyonce is the prime minister. It rained yesterday. Therefore, Beyonce is the prime minister.

A

Valid, but not sound

71
Q

A valid argument with an impossible conclusion is not _______

A

Sound

72
Q

Is it possible to have a sound argument with an impossible premise?

A

No

73
Q

Impossible premises make ____ arguments but not ______ arguments.

A

Impossible premises make VALID arguments but not SOUND arguments.

74
Q

For an argument of this form to be sound, how must it be formatted?

if P then Q
R
therefore, Q

A

R entails P or R entails Q will make it valid, and then the premises must be true to make it sound

75
Q

Form of this argument:

If I have more than $10, then I can afford this sandwich.
I have more than $100 dollars.
Therefore, I can afford this sandwich.

A

if P then Q
R
.˙. Q

76
Q

The following proposition can be categorized as which 2 connectives:

I did not tell Mother or Father.

A

Negation OR conjunction

77
Q

What does “P only if Q” mean?

A

Q is a necessary condition for P

78
Q

What does “If P, Q” mean?

A

P is a sufficient condition for Q

79
Q

What does “P if and only if Q” mean?

A

is necessary and sufficient for Q

80
Q

How can “P only if Q” be represented in SL? (2)

A

¬Q ⊃ ¬P or P ⊃ Q

81
Q

A grammatical sentence in SL is called a

A

well-formed formula (wff)

82
Q

What is an atom in SL

A

A capital letter (with optional numerical subscript)

83
Q

the connective that
governs the whole formula

A

Main connective

84
Q

Remember, our disjunction is ________, not ______.

A

inclusive, not exclusive

85
Q

Disjunctions are true any time _________

A

either disjunct is true.

86
Q

When constructing a truth table, _____ with the main connective.

A

End

87
Q

1 atom has ____ possibilities

A

2

88
Q

2 atoms have ____ possibilities

A

4

89
Q

3 atoms have ____ possibilities

A

8

90
Q

When is a conditional false

A

False only if antecedent is true and consequent is false
(1, 0 = 0)

True in all other cases

91
Q

Note that (P ⊃ Q) has the same truth conditions as.

A

(¬Q ⊃ ¬P)

92
Q

The biconditional (P ≡ Q) is true if P and Q have ________

A

the same truth value

93
Q

What should you do at the end of constructing a truth table?

A

Indicate the main connective column.

94
Q

Interpretations correspond to ______ in the truth table.

A

rows

95
Q

An interpretation satisfies a formula if __________

A

if the main connective of that formula receives a 1 in that row.

96
Q

If the main connective column has 0 in every row, the proposition is a
_______.

A

contradiction

97
Q

Contradictions are logically ________

A

Impossible

98
Q

If the main connective column has 1 in every row, the proposition is a _______

A

tautology

99
Q

A tautology proposition is logically _______

A

Necessary

100
Q

If the main connective column has 1 in at least 1 row and 0 in at least one row, the proposition is ________ .

A

contingent

101
Q

Two formulas are logically equivalent if and only if they have the same ___________

A

truth value on every interpretation

102
Q

An SL argument form is valid iff no interpretation satisfies all the
premises while _______ the conclusion

A

falsifying

103
Q

The argument form is valid iff there are no rows in which the premises are true and the conclusion is ____.

A

false

104
Q

Φ, Ψ |= Ω indicates an argument is _____

A

valid

105
Q

Φ, Ψ |/= Ω means that the argument is

A

invalid

106
Q

Entailment means

A

Any interpretation
that satisfies the left-hand side will also satisfy the right-hand side.

107
Q

|= means

A

Entailment

108
Q

Is the entailment symbol a part of SL

A

No, it just says something about SL

109
Q

How is P ⊃ Q different from
P |= Q

A

1st is a sentence of SL, 2nd is a claim about all interpretations

110
Q

The entailment claim is equivalent to saying the conditional is __________

A

true in all interpretations

111
Q

Any entailment claim is false if and only if there is a _____________.

A

counterexample —
an interpretation that satisfies the left and falsifies the right

112
Q

Conditionals with false _________
are always true.

A

antecedents

113
Q

So any entailment claim with a tautology on the right-hand side will be _______

A

True

114
Q

Entailment claims with an empty set on the left are always

A

right

115
Q

Any entailment claim with a contradiction on the left is ______

A

true

116
Q

⊥means

A

unsatisfiability

117
Q

What does unsatisfiability mean

A

every interpretation that satisfies the left will satisfy the
impossible

You can’t satisfy the impossible, so no interpretation on the left will be satisfied

118
Q

What is a partial truth table equivalent to

A

trying to force an invalid interpretation

119
Q

How do you draw a partial truth table

A

-Put a 0 under the main operator of the conclusion and a 1 under the main operator of each premise.

-Write down the truth value of anything you’re forced at this point.

-If nothing is forced, write a row for each possibility.

-If you can complete the process, then you have a counterexample to the validity of the argument.

120
Q

What is a partial truth table good for

A

Answering questions about
entailment more efficiently than drawing a complete truth table.

If you find they key pattern — satisfying the premises and falsifying the conclusion — the entailment claim is false.

PHIL 220 (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions