Chapter 9 Answer Key to Select Chapter Exercises

Exercise 9.1
1. An explanation is a statement or statements intended to tell why or how something is the case.
2. Inference to the best explanation is a form of inductive reasoning in which we reason from premises about a state of affairs to an explanation for that state of affairs.
6. Enumerative induction:
X per cent of the observed members of group A have property P.
Therefore, X per cent of all members of group A probably have property P.
Inference to the best explanation:
Phenomenon Q.
E provides the best explanation for Q.
Therefore, it is probable that E is true.
Analogical induction:
Thing A has properties P₁, P₂, P₃ plus the property P₄.
Thing B has properties P₁, P₂, and P_3.
Therefore, thing B probably has property P_4.
9. A theoretical explanation tries to explain why something is the way it is, why something is the case, or why something happened. A procedural explanation tries to explain how to do something.
10. Forensic pathologists use it, in seeking explanations for death. Or structural engineers, seeking explanations for why a bridge fell or a building failed. Mechanics use it in figuring out what’s wrong with your car.

Exercise 9.2
1. State of affairs: Applications from foreign students to Canadian universities being up these days; Explanation: Students are avoiding the United States.
4. State of affairs: Indigenous Canadians mistrust healthcare professionals; Explanation: Health professionals were involved in perpetrating historical injustices in the past.
7. State of affairs: Nursing students love Professor Walton’s class; Explanation: She takes dull material and makes it interesting.
10. State of affairs: Toby fudged the numbers; Explanation: he wanted to make his boss look good.

Exercise 9.3
2. Theoretical
3. Non-theoretical (interpretive)
5. Theoretical
8. Non-theoretical (procedural)
11. Non-theoretical (teleological)
15. Theoretical
17. Theoretical

Exercise 9.4
1. Theory 1: Workers now have fewer child-care related demands forcing them to skip work to stay home.
Theory 2: Workers were motivated to be more diligent by the pro-educational “atmosphere” fostered by the school’s presence in the community.
3. Theory 1: Jason has COVID-19.
Theory 2: Jason has another illness that happens to have exactly the same symptoms as COVID-19.
5. Theory 1: During the 1980s, many government programs that aided poor or disabled people were cut.
Theory 2: During the 1980s, the number of people needing food assistance increased because many middle-class people decided they would rather live on the streets than in the suburbs.
9. Theory 1: Penn and Teller use sophisticated versions of the traditional stage magician’s tricks—misdirection and sleight-of-hand—to give the illusion of having caught bullets in their teeth.
Theory 2: Penn and Teller have extremely strong teeth and fast reflexes.

Exercise 9.5
Passage 3
(1) Phenomenon being explained: Students who attend L’Ecole de Choix experience substantial academic success.
(2) Suggested theory: The school’s holistic approach to education promotes academic success.
(3) Plausible? Yes.
(4) Alternative theory: Consistent access to a well-designed curriculum is responsible for the students’ academic success.

Passage 4
(1) Phenomenon being explained: Relative lack of women on corporate boards in Canada.
(2) Suggested theory: Women don’t have the business instincts required.
(3) Plausible? No; there is no credible evidence that women in general have worse business instincts than men.
(4) Alternative theory: Discrimination rooted in sex is the cause of this phenomenon.

Exercise 9.6
1. More evidence is not always better; in some cases, there might be more evidence for one theory, but that evidence might be of low quality.
4. The criteria of adequacy are standards used to judge the worth of explanatory theories. They include testability, fruitfulness, scope, simplicity, and conservatism.
8. Simplicity is important because the theory that is simplest has the fewest ways of going wrong. The risk is that accepting a theory that is not simple requires that we first accept a lot of assumptions. Such assumptions may not in fact turn out to be justified, themselves.

Exercise 9.7
1. The simpler and more conservative theory: mere coincidence.
6. The simpler and more conservative theory: she hurt her leg skiing.
8. The simpler and more conservative theory: Apple’s new iPhone has more features and more innovations than ours does.

Exercise 9.8
1. The most plausible theory: computer error (especially if no one else is home!)
4. The most plausible theory: the increasing popularity of on-demand Internet media streaming services such as Disney+ and Netflix