Wesley C. Salmon, Logic (1984).
Preface to the 3d edition (1984)
Although logic is generally regarded as a branch of philosophy, its applications extend far beyond the limits of any single discipline. The critical standards of logic have application in any subject that employs inference and argument -- in any field in which conclusions are supposed to be supported by evidence. This includes every domain of serious intellectual endeavor, as well as the practical affairs of everyday life.
There are many logic textbooks -- that is, books intended mainly for use as texts in logic courses. This book has a different purpose. It is designed primarily for readers who, for various reasons, would find a basic knowledge of logic helpful. They might be taking courses in other branches of philosophy. They might be students of mathematics, science, language, history, or law. They might be interested in the presentation and criticism of reasoned arguments as they occur in exposition and debate. Or they might want to learn a little logic to help them evaluate their own thinking, as well as the enormous barrage of words -- directed at all of us in our everyday lives by television, radio, newspapers, magazines, colleagues, and friends -- that are intended to persuade us to purchase a certain product or to take a particular stand on some issue of public policy, politics, or religion. I am offering them a concise treatment of a wide range of topics in logic in the hope that it will be a practical supplement to the materials in their various areas of interest. If they are stimulated to pursue the study of logic a little bit farther, I would be most gratified. Looking to that end, a brief list of additional readings is given at the conclusion of the book.
Like many serious disciplines, logic may be studied for its intrinsic interest or for the purpose of application. These two aims are not mutually
exclusive. I have tried to satisfy each purpose to some extent. On the one hand, I have said quite a bit throughout the book concerning the scope, nature, and function of logic. I have tried to show the kinds of questions logic deals with and the kinds that are outside of its domain, hoping that readers will get a good basic idea of what logic is all about. On the other hand, I have tried to present topics that have important applications. In particular, every effort has been made to apply logical considerations to significant examples.
This book had its modest beginnings over twenty years ago as a sixteen page mimeographed pamphlet, which was distributed to students in introductory philosophy courses at Brown University. It was designed as a small handbook containing just a few basic logical concepts and argument forms to supplement the textbooks in these courses. Its basic purpose has not changed, but I believe that later versions provide a far more useful supplement in a broader range of contexts. It has subsequently gone through two previous editions in the Prentice-Hall Foundations of Philosophy Series. In each case the content of the book was substantially expanded to cover additional topics that had been omitted from earlier versions.
The third edition continues the trend. The main shortcoming of the second edition, I felt, was its rather cursory treatment of causal reasoning. It has become increasingly clear to me in recent years that arguments involving causal relationships occur with astonishing frequency in a wide variety of contexts. It is of vital importance for us to learn about how smoking, diet, and exposure to radiation bear upon the occurrence of cancer. News on such issues, and reports of studies that purport to furnish answers, appear regularly in newspapers and magazines. We are often informed about investigations into the causes of airplane crashes, fires, nuclear accidents, and a variety of other large or small catastrophes. We need to know much more about the causes of inflation, traffic fatalities, birth defects, and various diseases. We need to know more about the effects of the increased levels of carbon dioxide in the atmosphere that result from the use of coal as a fuel, as well as the effects of innumerable other chemicals that we introduce into the environment. Scientists are constantly trying to find out more about the effects of all sorts of drugs -- marijuana, alcohol, diet drugs, oral contraceptives, and new therapeutic agents. We all want to know why our tomato plants are not doing well this year, why our college-aged children have such strange taste in popular music, why last winter was especially cold, and why our cars would not start this morning. The list seems virtually endless, and each item in some fashion involves causal reasoning.
In an effort to do some justice to this important domain of logic, I have incorporated into the present edition three sections, 27-29, that deal with causal reasoning. Mill's methods (with the exception of the rnethod of residues) are presented as basic tools for dealing with causal relations, and
they are used to lead into more modern approaches that employ controlled experiments and statistical considerations. The treatment of the causal fallacies is, I believe, much improved in this edition. I hope that these three sections, which constitute the most important change, provide a more satisfactory introduction to causal reasoning.
Another significant change in this edition is the inclusion of a treatment of operational definitions in section 32. Given the widespread reference to operational definitions in virtually every scientific discipline, it seems essential to include them in a general discussion of definitions.
In addition, many small but important changes that correct and update the text have been incorporated. Especially significant, in my opinion, is the sincere attempt to remove any traces of sexual bias that were present in earlier editions. Events of the past decade have thoroughly convinced me of the harm that can result even from unintentional inequalities. I hope no infractions remain.
There is one revision that I seriously considered making, but in the end decided against. Robert McLaughlin has argued quite cogently that the traditional discovery/justification distinction (section 3) is better described as a distinction between invention and appraisal. In spite of the advantages of his new terminology, I decided -- since the traditional terms were used in the previous editions -- to stick with them in order to avoid terminological confusion. More importantly, however, he has shown that there can be helpful rational guidelines in the process of invention; thus there is, in some sense, a logic of discovery. Nevertheless it is not the sort of logic of discovery that I reject in this book, so I decided to confine mention of it to this Preface, instead of revising the discussion in section 3. An elementary handbook is not an appropriate place to report on the results of recent research.1
I am grateful to Prentice-Hall for the opportunity to bring out this third edition; I hope the new material will make the book more adequate for contemporary readers. I should like to express my warm thanks to Elizabeth and Monroe Beardsley, editors of this series, for their help and encouragement ever since I began work on the first edition, and to Tom Beauchamp. who has recently joined the group of editors, for valuable help on this edition. I am grateful to Chrystena Chrzanowski of Prentice-Hall for her skill and sensitivity in bringing the production of this book to a successful and timely conclusion. Finally, I should like to express my deepest gratitude to my wife, Merrilee Salmon, for her extremely useful suggestions and criticisms based upon many years' experience as a successful teacher of logic. Her help has been invaluable.
Wesley C. Salmon
1 See his essay, "Invention and Appraisal" in RobertMcLaughlin, ed., What? Where? When? Why? (Dordrecht: D. Reidel Publishing Co., 1982)
Preface to the 1st Edition (1963)
Although logic is generally regarded as a branch of philosophy, its applications extend far beyond the limits of any single discipline. The critical standards of logic have application in any subject which employs inference and argument -- in any field in which conclusions are supposed to be supported by evidence. This includes every domain of serious intellectual endeavor as well as the practical affairs of everyday life.
There are many excellent logic books, but most of them are large books, best suited for use as textbooks in logic courses. This book has a different purpose. It is designed primarily for the reader who, though he is not taking a logic course, would find a basic knowledge of logic helpful. He might be taking a course in some other branch of philosophy. He might be a student of mathematics, science, language, history, or law. He might be interested in the presentation and criticism of reasoned arguments as they occur in exposition and debate. Or he might want to learn a little logic to help him evaluate his own thinking and the enormous barrage of words intended to persuade. I offer him a small book in the hope that it will be a practical supplement to the materials of his own field of interest. If he is stimulated to pursue the study of logic farther, I would be most gratified. A brief list of supplementary readings is given at the end of the book.
Like many serious disciplines, logic may be studied for its own intrinsic interest or for the purpose of application. These two aims are not mutually exclusive. I have tried to satisfy each purpose to some extent. On the one hand, I have said quite a bit throughout the book concerning the scope, nature, and function of logic. I have tried to show the kinds
of questions logic deals with and the kinds which are outside its domain. I hope that the reader will get a good basic idea of what logic is all about. On the other hand, I have tried to present topics which have important applications. In particular, every effort has been made to apply logical considerations to significant examples.
I should like to express my deepest gratitude to Professors Elizabeth and Monroe Beardsley, editors of this series, to Professors William Alston, Stephen Barker, and Joel Feinberg, and to my wife, Nancy, all of whom kindly read my manuscript or parts of it and contributed extremely valuable criticisms and suggestions. My thanks are due also to Mrs. Betty Stokes for prompt and expert typing, and to Prentice-Hall, Inc., for their assistance in carrying out this project.
WESLEY C. SALMON