Most Californians are friendly. 4. Human beings are the only rational creatures on

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.