Question: It is a fact that major life forms now on earth were not at all represented in the past. There were no birds or mammals 250 million years ago. It is a fact that major life forms of the past are no longer living. There used to be dinosaurs and Pithecanthropus, and there are none now. It is a fact that all living forms came from previously living forms. Therefore, all present forms of life arose from ancestral forms that were different: birds arose from nonbirds and humans from nonhumans.
— R.C. Lewontin, Evolution/Creation Debate: A Time for Truth
Answer Options:
a. Argument; conclusion: It is a fact that all living forms … previously living forms.
b. Argument; conclusion: It is a fact that major life forms of the past are no longer living.
c. Argument; conclusion: It is a fact that major life forms … represented in the past.
d. Argument; conclusion: It is a fact that major life forms … previously living forms.
e. Argument; conclusion: All present forms of life … forms that were different.
Answer: e. Argument; conclusion: All present forms of life … forms that were different.
Question: After Sally stopped wearing Levi jeans, she started having vision problems. Therefore, to clear up her vision problems, Sally should go back to wearing her Levi’s.
Answer Options:
a. Inductive, weak.
b. Deductive, unsound.
c. Inductive, strong.
d. Deductive, invalid.
e. Deductive, valid.
Answer: a. Inductive, weak.
Question: As global warming continues, the temperature of the world’s oceans will rise. As ocean temperatures rise, hurricanes will become more intense. Therefore, hurricanes in the Caribbean will intensify in the years ahead.
Answer Options:
a. Inductive, weak.
b. Deductive, invalid.
c. Inductive, strong.
d. Deductive, sound.
e. Deductive, invalid.
Answer: b. Deductive, invalid.
Question: Given that figure A is an equilateral triangle, and one of its sides has a length of 1 foot. It follows that its area is less than 1 square foot.
Answer Options:
a. Inductive, strong.
b. Inductive, uncogent.
c. Deductive, valid.
d. Deductive, sound.
e. Deductive, invalid.
Answer: a. Inductive, strong.
Question: James Watson, co-discoverer of the structure of the DNA molecule, says that Charles Darwin is the most important person to have ever lived. Therefore, it must be the case that Charles Darwin is indeed the most important person to have ever lived.
Answer Options:
a. Inductive, strong.
b. Deductive, invalid.
c. Inductive, weak.
d. Inductive, cogent.
e. Deductive, valid.
Answer: c. Inductive, weak.
Question: If the northern pike is a ferocious predator, then it is a threat to lake trout. The northern pike is indeed a threat to lake trout. Therefore, the northern pike is a ferocious predator.
Answer Options:
a. Inductive, weak.
b. Inductive, strong.
c. Deductive, valid.
d. Inductive, cogent.
e. Deductive, invalid.
Answer: c. Deductive, valid.
Question: Either Leonardo da Vinci or Andrew Wyeth painted the Mona Lisa. But it clearly wasn’t da Vinci. Therefore, Andrew Wyeth painted the Mona Lisa.
Answer Options:
a. Inductive, weak.
b. Deductive, valid.
c. Deductive, invalid.
d. Deductive, sound.
e. Inductive, strong.
Answer: b. Deductive, valid.
Question: A week ago we invited Charlie to a party, and within two hours he became drunk and obnoxious. The same thing happened when Theresa invited him three weeks ago. Therefore, it would not be a good idea for Daisy to invite him to next week’s party, because the same thing will probably happen again.
Answer Options:
a. Inductive, strong.
b. Deductive, invalid.
c. Inductive, weak.
d. Deductive, valid.
e. Inductive, cogent.
Answer: a. Inductive, strong.
Question: Henry and Carl, who are neighbors, are about the same age, and they both have heart conditions. Henry takes Digitoxin for his heart, and it relieves his symptoms. Therefore, it would be a good idea for Carl to take the same medicine for his heart.
Answer Options:
a. Deductive, valid.
b. Deductive, invalid.
c. Inductive, cogent.
d. Inductive, weak.
e. Inductive, strong.
Answer: d. Inductive, weak.
Question: Some statements about the human condition are commercial failures, since some novels are commercial failures, and some novels are statements about the human condition.
Answer Options:
a. Inductive, weak.
b. Inductive, strong.
c. Deductive, invalid.
d. Deductive, valid.
e. Inductive, unsound.
Answer: c. Deductive, invalid.
Question: The pop-up message on your computer screen says “Earn $10,000 per week. Call 306-981-4872.” Therefore, if you call that number you can earn $10,000 per week.
Answer Options:
a. Deductive, invalid.
b. Deductive, valid.
c. Inductive, strong.
d. Inductive, cogent.
e. Inductive, weak.
Answer: e. Inductive, weak.
Question: Louis graduated from college after Cheri, and Cheri graduated before Denise. Therefore, it follows necessarily that Louis graduated before Denise.
Answer Options:
a. Deductive, valid.
b. Deductive, invalid.
c. Inductive, sound.
d. Inductive, strong.
e. Inductive, weak.
Answer: b. Deductive, invalid.
Question: No taggers are publicly spirited citizens, because all taggers are criminals, and no criminals are publicly spirited citizens.
Answer Options:
a. Inductive, cogent.
b. Deductive, invalid.
c. Deductive, valid.
d. Inductive, weak.
e. Inductive, strong.
Answer: c. Deductive, valid.
Question: After Scott started the engine in his old Chevy, the car backfired several times, and clouds of smoke came from the exhaust pipe. Apparently something must be wrong with the engine.
Answer Options:
a. Deductive, valid.
b. Inductive, weak.
c. Deductive, invalid.
d. Inductive, strong.
e. Inductive, cogent.
Answer: d. Inductive, strong.
Question: Laura is the sister of either Rachel or Sandy, and Sandy is the sister of Beth. Therefore, it follows necessarily that Laura is the sister of Beth.
Answer Options:
a. Deductive, valid.
b. Deductive, invalid.
c. Inductive, strong.
d. Inductive, weak.
e. Inductive, cogent.
Answer: b. Deductive, invalid.
Question: Beneath the image of Thomas Jefferson on this U.S. five-cent coin we see “1975.” It must be the case that the coin was minted in 1975.
Answer Options:
a. Deductive, invalid.
b. Inductive, strong.
c. Deductive, valid.
d. Inductive, weak.
e. Deductive, sound.
Answer: b. Inductive, strong.
Question: When asked how to address the militaristic ambitions of Syria, two Republican senators said we should drop bombs on Damascus, and a third said we should invade. The obvious conclusion is that Republicans are all a bunch of war mongers.
Answer Options:
a. Inductive, strong.
b. Deductive, invalid.
c. Inductive, cogent.
d. Deductive, valid.
e. Inductive, weak.
Answer: e. Inductive, weak.
Question: If interest rates rise, then home sales will decline. Thus, if interest rates rise, then real estate prices will drop, because if home sales decline, then real estate prices will drop.
Answer Options:
a. Deductive, invalid.
b. Inductive, cogent.
c. Deductive, valid.
d. Inductive, weak.
e. Inductive, strong.
Answer: c. Deductive, valid.
Question: Which of the following are all nonarguments?
Answer Options:
a. Predictions, pieces of advice, reports.
b. Opinions, categorical syllogisms, explanations.
c. Expository passages, illustrations, disjunctive syllogisms.
d. Statements of belief, warnings, conditional statements.
e. Generalizations, causal inferences, propositions.
Answer: d. Statements of belief, warnings, conditional statements.
Question: Which of the following are all inductive arguments?
Answer Options:
a. Generalizations, arguments from authority, arguments based on signs.
b. Disjunctive syllogisms, arguments based on mathematics, arguments from definition.
c. Causal inferences, arguments from definition, predictions.
d. Arguments from analogy, arguments from authority, hypothetical syllogisms.
e. Categorical syllogisms, arguments from authority, predictions.
Answer: a. Generalizations, arguments from authority, arguments based on signs.
Question: Which of the following are all conclusion indicators?
Answer Options:
a. Implies that, accordingly, since.
b. For the reason that, it follows that, inasmuch as.
c. Therefore, for this reason, entails that.
d. Hence, thus, given that.
e. Given that, as indicated by, seeing that.
Answer: c. Therefore, for this reason, entails that.
Question: In the expression “Hard water causes spots on glass because it contains calcium and magnesium salts that remain when the water dries,” the statement “It contains calcium and magnesium salts that remain when the water dries” is called the:
Answer Options:
a. Explanandum.
b. Consequent.
c. Premise.
d. Conclusion.
e. Explanans.
Answer: e. Explanans.