Phil
106: Critical Thinking
LARKIN:
Fall 2002
TEST
#2: Review
Truth-Functional
Logic
I.
Multiple Choice: (Directions: Choose the best available answer for each of the
questions below. Clearly record your
choices on the separate answer sheet provided.)
A.
Truth and Validity
1.
Example:
If an argument is invalid,
then we definitely know which of the following:
a.
It
has all true premises and a true conclusion
b.
It
has all true premises and a false conclusion
c.
It
has some false premise
d.
None
of the above
2.
Read:
Chapter One 1.7 and 1.9
B.
Translations
1.
Example:
Which of the following is the best symbolic
translation of the English sentence “Both Barry will hit a home run if the
Cardinals do not win and Barry will hit a home run unless the Cardinals win” (B
= Barry will hit a home run, C = Cardinals will win):
a.
(B
É C) · (B É
C)
b.
(B
É ~C) · (B É
C)
c.
(C
É B) · (B v C)
d.
(~C
É B) · (B v C)
2.
Read: Chapter Eight: 8.1-8.3
3.
Practice: p. 311 IV, p. 320 III
1.
Example:
If A and B
are true but P and Q are unknown, which of the following claims are definitely
true:
a.
(A
· ~B) · (P v Q)
b.
(A · ~B) v (P v A)
c.
(A
· ~B) É (P v Q)
d.
both
a and b
e.
both
b and c
2.
Read:
Chapter Eight: 8.1-8.3
3.
Practice:
p. 310 II and III, p. 319 I, II
1.
Example:
“If the Cardinals do not win, then Barry will go
deep at least once. Since the Cardinal
will win, Barry will not go deep at least once.” This argument is best described as which of the following:
a.
Affirming
the Antecedent
b.
Affirming
the Consequent
c.
Denying
the Antecedent
d.
Denying
the Consequent
2.
Read: Chapter Eight: 8.5 C and D
II.
Truth Table Analysis (Directions: Determine whether the following arguments are valid or not by
constructing a truth table)
(P v Q) É (Q ·
R)
~(R v Q)
/\ ~P