IN LOGIC: DEDUCTIVE AND INDUCTIVE WITH COPIOUS QUESTIONS AND EXAMPLES, AND A VOCABULARY OF LOGICAL TERMS. BY W. STANLEY JEVONS, M.A. PROFESSOR OF LOGIC IN OWENS COLLEGE, MANCHESTER, NEW EDITION. London and New York: MACMILLAN AND CO. 1892. PREFACE. IN preparing these Lessons I have attempted to show that Logic, even in its traditional form, can be made a highly useful subject of study, and a powerful means of mental exercise. With this view I have avoided the use of superfluous technical terms, and have abstained from entering into questions of a purely speculative or metaphysical character. For the puerile illustrations too often found in works on Logic I have generally substituted examples drawn from the distinct objects and ideas treated in the natural and experimental sciences; and in this and other respects have aimed at rendering these Lessons a suitable companion to a series of science school books. Logic is not only an exact science, but is the most simple and elementary of all sciences; it ought therefore undoubtedly to find some place in every course of education. The relations of propositions and the forms of argument present as precise a subject of instruction and as vigorous an exercise of thought, as the properties of geometrical figures, or the rules of Algebra. Yet every school-boy is made to learn mathematical problems which he will never employ in after life, and is left in total ignorance of those simple principles and forms of reasoning which will enter into the thoughts of every hour. Logic should no longer be considered an elegant and learned accomplishment; it should take its place as an indispensable study for every well-informed person. These Lessons I trust will introduce to the science many who have not leisure or inclination to read more elaborate treatises, and many who would not be attracted by the numerous but somewhat dry and brief compendiums published in past years. It is desirable that Lessons in Logic should be made the basis of many exercises, and for this purpose I have supplied abundance of questions and examples at the end of the book, some of which are selected from the examination papers of the Oxford, |