The Art of Reasoning: An Introduction to Logic and Critical Thinking, 4th edition

Book Preface

This is a book about thinking. It’s a book about how to think. In a broad sense, the word “thinking” refers to anything that goes on in our minds. When I say “a penny for your thoughts,” I want to know what’s on your mind—whether it’s a feeling, a memory, a question, an anxiety, a problem you’re trying to solve, or a daydream. As long as you are conscious, there is always something going on up there. In this sense, you can’t help thinking. You don’t need this book. You just have to stay awake. In a narrower sense, however, thinking is a particular kind of mental activity, the kind involved in solving a problem, planning an action, studying for a test, or defending your position on a controversial issue. This is still a pretty broad concept, but we have excluded some things.

In the first place, we can distinguish thinking from feeling. Thinking is a cognitive process we use in the attempt to gain knowledge or to understand something, as distinct from our emotional responses to things. This distinction does not mean, as people too often assume, that someone with strong emotions is necessarily illogical or that a logical person must be unemotional. On the contrary, there is no reason we cannot have both: clear, logical minds and passionate feelings. But thinking and feeling do have different roles to play, different jobs to do, in our mental lives.

Second, thinking is purposive. It differs from activities such as daydreaming and fantasizing in which we simply let our minds wander where they will. Thinking is something we have to do, usually with some degree of effort. And because it aims at a goal, it is something that can be done with varying degrees of success. You may or may not succeed in solving a problem, forming a plan, grasping something you read, or proving your case. In this way, too, it differs from daydreaming, where the concepts of success and failure don’t really apply. Thinking is a skill. It’s a skill that everyone has in some degree, but it is also a skill that everyone can improve.

How can we improve this skill? Let’s consider an analogy with the game of tennis. If we want to improve our skill at tennis, we need to do two things. We need to learn more about the rules and strategies of the game. And we need to practice the moves that implement those rules and strategies—to practice serving, volleying, rushing the net, and so forth. The same is true for the activity of thinking. There are certain rules and strategies of thinking, certain standards that tell us when we have achieved a clear understanding of some subject or succeeded in proving a case. Our first task is to learn what these standards are and to understand why they are correct. Our second task is to practice applying these standards to a variety of examples drawn from everyday life, from politics, and from the different subjects one studies in school. The more practice we get, the more effectively we can incorporate the standards of logic into our habits of thought. That’s why this book has a lot of exercises. Before we begin, let’s get an overview of the range of standards and techniques that we’re going to be learning about.

Contents:

PART ONE Language and Reasoning
CHAPTER 1 Classification 9
CHAPTER 2 Definitions 26
CHAPTER 3 Propositions 47
CHAPTER 4 Argument Analysis 67
CHAPTER 5 Fallacies 103
PART TWO: Deductive Logic
CHAPTER 6 Categorical Propositions 145
CHAPTER 7 Categorical Syllogisms 179
CHAPTER 8 Reasoning with Syllogisms 219
CHAPTER 9 Propositional Logic—Propositions 260
CHAPTER 10 Propositional Logic—Arguments 300
CHAPTER 11 Predicate Logic 360
PART THREE: Inductive Logic
CHAPTER 12 Inductive Generalizations 417
CHAPTER 13 Argument by Analogy 442
CHAPTER 14 Statistical Reasoning 456
CHAPTER 15 Explanation 483
CHAPTER 16 Probability 509