1.5: Review of Major Points

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Bradley H. Dowden
California State University Sacramento

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This chapter emphasized that logical reasoning is your guide to good decisions. It is also a guide to sorting out truth from falsehood. This chapter began with several case studies of logical reasoning. It also pointed out some common errors in reasoning. From these examples we were able to extract the following principles of logical reasoning: (1) ask for reasons before accepting a conclusion, (2) give an argument to support your conclusion, (3) tailor reasons to your audience, (4) design your reasons to imply the conclusion, (5) recognize the value of having more relevant information, (6) weigh the pros and cons, (7) consider the possible courses of action, (8) look at the consequences of these various courses of action, (9) evaluate the consequences, (10) consider the probabilities that those various consequences will actually occur, (11) delay making important decisions when practical, (12) assess what is said in light of the situation, (13) don't take people too literally, (14) use your background knowledge and common sense in drawing conclusions, (15) remember that extraordinary statements require extraordinarily good evidence, (16) defer to the expert, (17) remember that firmer conclusions require better reasons, (18) be consistent in your own reasoning, (19) be on the lookout for inconsistency in the reasoning of yourself and others, (20) check to see whether explanations fit all the relevant facts, (21) you can make your opponent's explanation less believable by showing that there are alternative explanations that haven't been ruled out, (22) stick to the subject, and (23) don't draw a conclusion until you’ve gotten enough evidence.

These principles are merely pieces of advice; they are not rules or recipes. All the points, principles, and problems discussed in this chapter will receive more detailed treatment in later chapters. Those chapters will continue to systematically explore the intricacies of being logical. Although not all the logical principles in the world will be introduced in this book, all the most important ones will be. Regarding the problem of whether some are more important than others: not to worry; the relative importance of the principles will become clear as we go along.

As you investigate arguments during the course, you will improve the following skills:

RECOGNITION of arguments
EVALUATION of arguments
CREATION of arguments