Answers to Selected Exercises
ANS-9
4. Some bankers are vegetarians. No anarchists are bankers.
So, some anarchists are not vegetarians. Bankers
Anarchists Vegetarians
X
Invalid
7. No poker players are early-risers. Some firefighters are early-risers.
So, some firefighters are not poker players. Early–risers
Firefighters Poker players
X
Valid
10. No Fords are Pontiacs. All Escorts are Fords.
So, some Escorts are not Pontiacs. Fords
Escorts Pontiacs
Invalid
13. No landlubbers are sailors. Some sailors are not pirates.
So, some pirates are not landlubbers. Sailors
Pirates Landlubbers
Invalid
X
16. No fish are reptiles. All trout are fish.
So, some trout are not reptiles. Fish
Trout Reptiles
Invalid
7.
Women U.S. presidents or vice presidents
10.
Worlds greatest golfers South Americans
X
E
XERCISE
9.2
1. All psychiatrists are doctors. 4. All Mustangs are Fords.
7. All players due to report on Monday are persons who are pitchers or catchers.
10. All persons who may use the Teachers’ Lounge are teachers.
13. All persons God loves are persons that dwelleth in wisdom.
E
XERCISE
9.3
I. 1. All maples are trees.
4. All insects are animals. 7. Some things that glitter are not gold things.
10. All persons that hit are persons who swing the
bat. 13. Some birds are birds that cannot f ly. Or: Some
birds are not things that f ly. 16. All places where the grass is greener are places on
the other side. 19. Some polar bears are bears that live in Canada.
22. All liars are thieves. 25. Most humans are humans who live lives of quiet
desperation. 28. All persons who persevere in error are fools.
31. All statements that are certain are statements iden- tical to the statement “Nothing is certain.”
34. All villains dwelling in Denmark are arrant knaves.
E
XERCISE
9.4
I. 1. No barracuda are pets.
No sharks are barracuda. So, no sharks are pets.
Barracuda
Sharks Pets
Invalid
ANS-10
Answers to Selected Exercises Political scientists
Persons who favor campaign finance reform
Social scientists
Valid
X
13. All tax evaders are lawbreakers. No lawbreakers are model citizens.
So, no model citizens are tax evaders. Lawbreakers
Model citizens Tax evaders
Valid
16. No harmless acts are immoral acts. Some lies are not harmless acts.
So, some lies are not immoral acts. Harmless acts
Lies Immoral acts
Invalid
X
19. All persons who eat pizza every night are persons at risk for heart disease.
Some persons who are at risk for heart disease are cab drivers.
So, some cab drivers are persons who eat pizza every night.
Persons at risk for heart disease
Cab drivers Persons who eat
pizza every night
Invalid
X
C
HAPTER
10
E
XERCISE
10.1
I. II.
III. 1. p
1. T 1. T
4. p q 4. T
4. T 7. p q
7. F 7. F
10. p q 10. F
10. T
19. Some butchers are not bakers. No butchers are candlestick makers.
So, some candlestick makers are not bakers. Butchers
C andlestick makers
B akers
X
Invalid
II. 1. No Nobel Prize winners are rock stars.
Some astrophysicists are Nobel Prize winners. Therefore, some astrophysicists are not rock stars.
Nobel Prize winners
Astrophysicists Rock stars
Valid
X
4. All liberals are big spenders. All persons identical to Senator Crumley are big
spenders. So, all persons identical to Senator Crumley are
liberals. Big spenders
Senator Crumley Liberals
Invalid
7. Some lawyers are not golfers. All lawyers are persons who have attended law
school. So, some persons who have attended law school are
not golfers. Lawyers
Persons who have attended law school
Golfers
Valid
X
10. All political scientists are social scientists. Some political scientists are persons who favor
campaign finance reform. So, some persons who favor campaign finance
reform are social scientists.