Comparative Reasoning Think “This is Like That” Chapter 12 Comparative Reasoning Think “This is Like That”

Comparative, Ideological, and Empirical Inferences Comparative reasoning (or this-is-like-that thinking) enables us to: Make interpretations, draw inferences, or offer explanations by relying on something that is: More familiar in order to understand something that is less familiar © 2013 Pearson Education, Inc. All rights reserved.

“This Is Like That”—Recognizing Comparative Reasoning Gardens of Comparatives People cultivate an exceptional variety of ways to express comparative reasoning Most comparative reasoning doesn’t appear as a fully developed argument: With reasons and claims © 2013 Pearson Education, Inc. All rights reserved.

“This Is Like That”—Recognizing Comparative Reasoning Powerful Comparisons Connect Intellect and Emotion Knowing that vivid comparisons can move hearts as well as minds, speechwriters: Strive to associate their ideas with memorable comparisons as these next two examples illustrate © 2013 Pearson Education, Inc. All rights reserved.

Breaking Down Comparative Reasoning © 2013 Pearson Education, Inc. All rights reserved.

Evaluating Comparative Inferences Do the Four Tests of Acceptability Apply? First test Are the premises all true? Second test Are there counterexamples and how difficult is it to imagine them? © 2013 Pearson Education, Inc. All rights reserved.

Evaluating Comparative Inferences Third test Are the premises relevant to the truth of the conclusion? Fourth test Does the truth of any premise depend on the truth of the conclusion? © 2013 Pearson Education, Inc. All rights reserved.

Evaluating Comparative Inferences The purpose of comparative reasoning is to: Illustrate, illuminate, suggest, or hypothesize, rather than to prove that a conclusion is true Five Criteria for Evaluating Comparative Reasoning Why is comparative reasoning so potentially valuable? © 2013 Pearson Education, Inc. All rights reserved.

Evaluating Comparative Inferences If the comparison is reasonable, then some salient feature of the more familiar object is: Also a salient feature of the less familiar object Comparative inferences, including analogical arguments, are inductive and probabilistic Familiarity © 2013 Pearson Education, Inc. All rights reserved.

Evaluating Comparative Inferences Successful comparisons direct the listener’s attention to that which is more familiar Simplicity A measure of the relative complexity of the comparison Simpler comparisons are often more readily understood and remembered © 2013 Pearson Education, Inc. All rights reserved.

Evaluating Comparative Inferences Comprehensiveness The virtue of simplicity must be balanced with the importance of comprehensiveness Productivity The capacity of a comparison to bring to mind unexpected new ideas that go: Beyond the points of comparison initially mentioned © 2013 Pearson Education, Inc. All rights reserved.

Evaluating Comparative Inferences Testability The capacity of a comparison to project consequences that have: The potential to be shown to be false, inapplicable, or unacceptable The criterion of testability enables us to evaluate the acceptability of a proposed comparison © 2013 Pearson Education, Inc. All rights reserved.

Evaluating Comparative Inferences Shaping Our View of the Universe for Two Thousand Years The Many Uses of Comparative Inferences Comparative reasoning is used in discussions of ethics: Such as to compare cases and infer obligations © 2013 Pearson Education, Inc. All rights reserved.

Evaluating Comparative Inferences The basic character of the appeal to precedent is the assertion that: The case in question is so much like the prior case that the ruling that applied there should apply here A comparison’s persuasive power depends heavily on the suggested parallelism Simplicity and Hypothetical Entities © 2013 Pearson Education, Inc. All rights reserved.

© 2013 Pearson Education, Inc. All rights reserved.