Identifying Argument Patterns Flashcards
1
Q
- PorQ.
- -P.
- Q.
A
Argument by Elimination
Valid Sentential
2
Q
- IfPthenQ. 2. P.
3. Q.
A
Affirming the Antecedent
Valid Sentential
3
Q
- If P then Q.
- If Q then R.
- If P then R.
A
Hypothetical Syllogism
Valid Sentential
4
Q
- P.
- Q.
- P and Q.
A
Conjunction
Valid Sentential
5
Q
- If P then Q.
- -Q.
- -P.
A
Denying the Consequent
Valid Sentential
6
Q
- If P then Q.
2. If -Q then -P.
A
Contraposition
Valid Sentential
7
Q
- P and Q
2. P.
A
Simplification
Valid Sentential
8
Q
- -P
2. P
A
Double Negation
Valid Sentential
9
Q
- P ifandonlyif Q.
- -P.
- -Q.
A
Equivalence
Valid Sentential
10
Q
- If P then Q.
- -P
- -Q.
A
Denying the Antecedent
Invalid Sentential
11
Q
- If P then Q.
- Q.
- P.
A
Affirming the Consequent
Invalid Sentential
12
Q
- All As are Bs.
- x is an A.
- x is a B.
A
Valid Predicate
13
Q
- All As are Bs.
- All Bs are Cs.
- All As are Cs.
A
Valid Predicate
14
Q
- All As are Bs.
- x is not a B.
- x is not an A.
A
Valid Predicate
15
Q
- No As are Bs.
- x is an A.
- x is not a B.
A
Valid Predicate
16
Q
- All As are Bs.
- x is not an A.
- x is not a B.
A
Invalid Predicate
17
Q
- All As are Bs.
- xisaB.
- xisanA.
A
Invalid Predicate
18
Q
- Most As are Bs.
- x is an A.
- x is a B.
A
Cogent
19
Q
- x is an A
- x is a B
- Most ABs are Cs.
- x is a C
A
Cogent
20
Q
- Most As are Bs.
- x is not an A.
- x is not a B.
A
Ill Formed
21
Q
- Most As are Bs.
- x is a B.
- x is an A.
A
Ill Formed
22
Q
Affirming the Antecedent Ex.
A
- If the Prime Minister is at 24 Sussex Drive, then the Prime Minister is in Ottawa.
- The Prime Minister is at 24 Sussex Drive.
- The Prime Minister is in Ottawa.
Affirming the Antecedent - If P then Q. 2. P.
- Q.
23
Q
Denying the Consequent Ex
A
- If the Prime Minister is at 24 Sussex Drive, then the Prime Minister is in Ottawa.
- The Prime Minister is not in Ottawa.
- Prime Minister is not at 24 Sussex Drive.
Denying the Consequent - If P then Q.
- -Q.
- -P.
24
Q
Hypothetical Syllogism Ex
A
- If the Prime Minister is at 24 Sussex Drive, then the Prime Minister is in Ottawa
- If the Prime Minister is in Ottawa, then the Prime Minister is not on vacation.
- If the Prime Minister is at 24 Sussex Drive, then the Prime Minister is not on vacation.
Hypothetical Syllogism - If P then Q. 2. If Q then R. 3. If P then R.
25
3 ways to test for validity:
1. Find a counterexample to the argument.
2. Find a counterexample to the argument’s pattern.
3. Check the list of argument patterns.
26
Define Cogency
CD2: An argument is cogent if and only if it is not valid but it follows a pattern such that all arguments following that pattern have a conclusion that is probably true if the premises are true.
