Intro. to Logic
Practice Test 2
For each of the following syllogisms do the following: (a) Test with a Venn diagram, (b) State whether
valid or invalid from the Boolean standpoint, (c) Name any rules broken or fallacies committed; if no rules
are broken write "none," (d) Name the mood and figure.
1. All M are P.
Some S are M.
Some S are P.
a.
b. _______________
c. _______________
d. _______________
2. All M are P.
No M are S.
No S are P.
a.
b. _______________
c. _______________
d. _______________
3. All M are P.
All M are S.
Some S are P.
a.
b. _______________
c. _______________
d._______________
4. All M are P.
No M are S.
No S are P.
a.
b.__________________
c.__________________
D___________________
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Reconstruct the syllogistic form from the following combinations of mood and figure. Use the letters P, S,
and M to designate the major, minor, and middle terms, respectively. Then check the validity of the
syllogism by utilizing the six rules. State the relevant fallacy, if any.
4. OAO-3
____________________________________
Fallacy:_____________________
____________________________________
____________________________________
5. AOO-4
____________________________________
Fallacy:_____________________
____________________________________
____________________________________
6. (pick a mood and figure, any one! Do it over and over.)
Given that A and B are true and X and Y are false, determine the truth values of the following molecular
propositions. Show your work and circle the answer.
7-10: page 312, part III, #’s 15, 21 and 23.
Given that A and B are true, X and Y are false, and P and Q have unknown truth value, determine the truth
values of the following molecular propositions. If the truth value cannot be determined, write
"undetermined." Show your work and circle the answer.
11-13: page 313, part IV, #'s 10-12
Use truth tables to determine whether the following propositions are tautologous, self-contradictory or
contingent.
14-16. Page 319, part I, #’s 2, 6, and 13
Use truth tables to determine whether the following pairs of propositions are logically equivalent,
contradictory, or consistent. (10 points each, 2 questions)
17-20. Page 320, Part II, #’s 3,5,6,12
Determine whether the following arguments are valid or invalid by constructing an ordinary truth table for
each. If an argument is invalid, circle the pertinent truth values.
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21 and 22. Page 325, Part II, #’s 5 and 11
Use indirect truth tables to determine whether the following arguments are valid or invalid.
23. A  B / (A  B)  C / A  (C  D) // A  D
24. K  (L v M) / L  M / M  K / K v L // K  L
25. page 332, number 14
Use indirect truth tables to determine whether the following sets of statements are consistent or inconsistent.
26 and 27. Page 332, numbers 3 and 8.
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