ELEMENTS OF LOGIC: ON THE BASIS OF LECTURES BY WILLIAM BARRON, F. R. S. E. PROFESSOR OF BELLES-LETTRES AND LOGIC IN THE UNIVERSITY OF ST. ANDREWS. WITH LARGE SUPPLEMENTARY ADDITIONS, CHIEFLY FROM WATTS, ABERCROMBIE, BROWN, WHATELY, MILLS, AND THOMSON. EDITED AND COMPILED BY REV. JAMES R. BOYD, AUTHOR OF ELEMENTS OF RHETORIC, EDITOR OF KAMES' CRITICISM, AND OF ENGLISH POETS WITH NOTES, ETC. NEW YORK: A. S. BARNES & CO., 51 & 53 JOHN-STREET. 1856. Phil 5041.8 1862, Nov, 18. Gift of Richard Green Parker, Ey. Entered according to Act of Congress, in the year 1856, BY A. S. BARNES & CO., In the Clerk's Office of the District Court of the United States for the Southern District of New York. RICHARD C. VALENTINE, GEORGE W. WOOD, Printer, No. 2 Dutch-street. INTRODUCTORY OBSERVATIONS. THE Lectures which constitute the basis of the present work were read by the learned author, during twenty-five sessions, in the University of St. Andrews, and may consequently be presumed to have been elaborated with great care, and to be worthy of the attentive study of all who desire to become acquainted with the science and the art of Reasoning. As the Lectures are few and concise, there seemed to be occasion, in fitting them the better for a text-book in schools, or even for private perusal, to supplement them occasionally, from the works of distinguished writers on Logic, on points where, for practical utility, a more full discussion of the subject is needed; and also to introduce various important topics upon which Professor Barron had neglected to offer observations. As stated in the title-page, the works to which the compiler has had recourse for this purpose, are, chiefly, those of Dr. Isaac Watts, Dr. Abercrombie, Archbishop Whately, Dr. Thomas Brown, John Stuart Mills, and William Thomson. The con tributions gained from these standard sources will be found at least equal in value, and nearly also in amount, to the Lectures. It is hoped, therefore, that a work has thus been constructed which will be found to possess some advantages over the text-books now most generally used. One peculiar feature of it, is the omission of a great deal of perplexing and useless matter relating to the Syllogism; and yet it presents a full discussion of the value and functions of that ancient form of rea 4 INTRODUCTORY OBSERVATIONS. soning. The opinions and views of distinguished authors on this interesting branch of the subject are largely quoted, that the student may be led to a discovery of the true state of the case. He is not, moreover, here subjected to the irksome task of learning a huge mass of intricate and unprofitable details about syllogistic Moods and Figures, such as are found in most treatises on the science of Logic. The author of "The Philosophy of Rhetoric," Dr. George Campbell, not a mean reasoner, nor an indifferent critic in matters of this kind, in that celebrated work observes: "It is long since I was convinced, by what Mr. Locke hath said on the subject, that the syllogistic art, with its figures and moods, serves more to display the ingenuity of the inventor, and to exercise the address and fluency of the learner, than to assist the diligent inquirer in his researches after truth. The method of proving by syllogism appears, even on a superficial review, both unnatural and prolix. The rules laid down for distinguishing the conclusive from the inconclusive forms of argument, the true syllogism from the various kinds of sophism, are at once cumbersome to the memory and unnecessary in practice. No person, one may venture to pronounce, will ever be made a reasoner who stands in need of them. In a word, the whole bears the manifest indications of an artful and ostentatious parade of learning, calculated for giving the appearance of great profundity to what in fact is very shallow. Such, I acknowledge, have been, of a long time, my sentiments on the subject. On a nearer inspection, I cannot say I have found reason to alter them, though I think I have seen a little further into the nature of the disputative science, and consequently into the grounds of its futility." After a series of observations made in vindication of these criticisms upon what he calls the scholastic art of disputation, Dr. Campbell concludes in the following terms: "When all erudition consisted more in an acquaintance with words, and INTRODUCTORY OBSERVATIONS. address in using them, than in the knowledge of things, dexterity in this exercitation conferred as much lustre on the scholar as agility in the tilts and tournaments added glory to the knight. In proportion as the attention of mankind has been drawn off to the study of Nature, the honors of this contentious art have faded, and it is now almost forgotten. There is no reason to wish its revival, as eloquence seems to have been very little benefited by it, and philosophy still less. Nay, there is but too good reason to affirm that there are two evils, at least, which it has gendered. These are, first, an itch of disputing on every subject, however incontrovertible; the other, a sort of philosophic pride, which will not permit us to think that we believe any thing, even a self-evident principle, without a previous reason or argument. In order to gratify this passion, we invariably recur to words, and are at immense pains to lose ourselves in clouds of our own raising. We imagine we are advancing and making wonderful progress, while the mist of words in which we have involved our intellect hinders us from discerning that we are moving in a circle all the time."-(Philosophy of Rhetoric, p. 92.) Of the ancient Logic (which Archbishop Whately and others have endeavored to revive), the same views were entertained substantially by Dr. Thomas Reid and Dr. Adam Smith, Professors of Moral Philosophy in the University of Glasgow, and by Professor Dugald Stewart, of the University of Edinburgh. One of the pupils of Dr. Adam Smith, and who was ranked among his most valued friends during life, makes the following significant statement: "In the Professorship of Logic, to which Mr. Smith was appointed on his first introduction into the University of Glasgow, he soon saw the necessity of departing widely from the plan that had been followed by his predecessors, and of directing the attention of his pupils to studies of a more interesting and useful nature than the logic and metaphysics of the schools. Accordingly, after exhibiting a gen |