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I, therefore, trust that this GRAMMAR OF LOGIC AND INTELLECTUAL PHILOSOPHY will be found adequate to initiate youth inz that history, and to resolve such inquiries respecting the operations of their own minds, as they daily experience.

The plan of the volume is briefly as follows:

The First Book is devoted exclusively to the Definition of terms - Preliminary explanations - Enumeration of principles which are taken for granted - Inquiries into the nature and value of hypotheses — The doctrine of analogy – The

proper means of knowing the operations of our own minds — The difficulty of attending to these operations, with observations which may assist us in overcoming this difficulty, - and, finally, A comprehensive division of the powers of the human mind.

The Second Book embraces Elements of Intellectual Philosophy, calculated to instruct youth in a knowledge of those principles to which the development of the mental faculties may be traced, and upon which we rest all our knowledge of legitimate logic. These elements comprise analyses of the faculties, Consciousness — Sensation Perception -Attention - Conception Abstraction Association - Memory - Imagination — Judgment -Reason — Moral Perception.

The Third Book treats on Subjects of collateral Inquiry with the Intellectual Powers, - such, for example, as the Primary and Secondary qualities of bodies — Natural language and signs — Matter and Space - Duration, Extension, and Number — Identity -The train of thought in the Mind — and Prejudices.

The Fourth Book The Grammar of Logic — unfolds the doctrines of Ideas - Propositions — Sophisms — Reasoning and Syllogism.

The Fifth Book concludes the volume, with a brief sketch of The Philosophy of Human Knowledge, as it is addressed to the MEMORY, the UNDERSTANDING, an he IMAGINATION.

The foregoing arrangement was dictated by motives which the following observations pretend to explain.

In a work that treats of Logic and Intellectual Philosophy, and where selection is so imperiously required, there must be an equal necessity that certain fixed and intelligible principles slıould be preëstablished. Nor, in handling subjects that have been controverted, and which, from their very nature, are ever liable to discussion, is there any thing of more consequence than agreement, at the outset, about the language we use; for, when, in philosophical disquisitions, we are once agreed respecting the signification of the words and terms we employ, it is unlikely that we shall differ about their application, provided we continue to use them in the sense which we had already affixed to them: hence the position and division of Book First.

A knowledge of the powers of the human mind, and of the science of Intellectual Philosophy, furnishes the proper basis upon which every other science is grounded, because thie human

faculties are the instruments by which alone invention in all the sciences can be accomplished.

The examination and analysis of these faculties reciprocally open sources of intellectual improvement, and exercise the student in habits of thinking, judging, reasoning, and communication, upon which depend, not merely the study of logic, and the further prosecution of science, but almost entirely the active business of life. Nor does it appear to me that any other process could, with equal certainty of success, be adopted, by which the mind of youth, launching into a new and pleasing field of speculation, might be enabled to form an estimate of its own powers, of the acquisitions it has made, of the habits it has formed, and of the further improvements of which it is susceptible. For, when the student has acquired those habits of attention, and that capacity of observation, which the study of his intellectual powers must necessarily give him, it is then, and not till then, I have no hesitation in affirming, that he is qualified to enter upon a philosophical, but popular course of Logic.

Besides, as the progress of the intellectual powers is not prematurely quickened, an acquaintance with the phenomena of the human mind, arranged so as to enable us to profit by our personal experience, cannot be a subject of abstract speculation, but must be the channel through which we advance to the highest endowments of the understanding.

But the professed object of Logic is to teach us the right USE OF REASON, both in the investigation and in the commuwication of TRUTH.

I have already pointed out the relation in which I conceive RHETORIC to stand to GRAMMAR and Logic, and, without arrogating pretensions to superior discernment, which would only lay me open to the suspicion of a particular prejudice, I do not see hor: it is possible to conduct ingenuous youth upwards from the correctness of their taste to the cultivation of their understanding, but by previously explaining to them the faculties of the mind, and their various operations with which we are immediately or remotely conversant, the circumstances favorable or unfavorable to the development of those faculties, and the means by which their improvement may be most successfully undertaken.

In the execution of this task, I was also laid under an inperious necessity of banishing from my work all the trifling subtilties of the ancient Logicians, all the logomachy of the schools, all the puzzling distinctions which perplex us in most of the popular treatises of our modern philosophers. But I do not thence lay claim to any new discoveries either in the science of mind, or in the art of Logic.

It has been with me a principle of paramount importance, to endeavor to select the most unexceptionable materials from the most approved works of my predecessors or contemporaries,

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employed, like myself, in extending the elements of science. And those subjects which seemed best adapted for the employment of youth at the commencement of their philosophical studies, I have labored to present to them in this BOOK with faithfulness and assiduity in their selection, and with simplicity and intelligibility in their form and arrangement.

Of the difficulty of executing an acceptable compilation of the ELEMENTS OF THE SCIENCE OF MIND with analyses of the intellectual powers, in the order of their connection and dependence, it would be superfluous to reason with empirics who have not added one iota to literature or to science. But the philosopher and the critic know that judgment in selection, perspicuity of style, and compression of argumentation, the great requisites of every writer who would not become dull from crudity of conception, nor obscure from prolixity of reasoning, are indispensable to give anciently-received truths and established modern discoveries those charms which shall fascinate readers in the purple bloom of youth. And in pleasing satisfaction will my mind now repose, if, among the unambitious pretensions of a compiler, the reasonings which support those truths shall be found to possess conciseness, and the illustrations of those discoveries no more expansion of proof than the different steps of their relative processes required; for, with youth whose mental faculties we would, by active discipline, invigorate, improve, and embellish, brevity is not less the soul of reasoning than of wit. Their knowledge, however, is not to rest on tarnished fragments struck off from splendid systems, nor on defective models the relics of doubtful institutes; but on the details of human knowledge, and such discipline of education as shall accustom them to exert their intellectual faculties, without preparation, and render them prompt in expedient, and active in resource.

Sufficient, however, has been said on Book Second, as well to show its high importance, as to satisfy every impartial reader, that, to have omitted it, or assigned to it any other place in the volume, would have evinced culpable neglect or capricious arrangement.

To have blended with the subjects in the SECOND Book those which constitute the Third, would have created a species of confusical, which, in elementary works, should always be avoided; and, besides, the relative importance this Book bears to the Second and the Fourth reciprocally, allotted to it that neutrality which makes it of easier reference to the numerous subjects that it may collaterally illustrate, or with which, in many instances, its materials may be directly conjoined. Nor is this the only light in which "Book Third may be viewed. If the subjects of which it is composed be considered abstractedly, then does the student enter upon disquisitions and analyses of separate branches of INTELLECTUAL PHILOSOPHY, of primary importance on his entrance upon philosophical studies. But

it is unnecessary to offer proofs for that which is clear as sunshine.

Of Book Fourth, assigned to PURE Logic, I shall say a few words. But I premise, that of all arts, that surely is entitled to attention which pretends to tell us how we may improve and properly employ the UNDERSTANDING,—the faculty by which man is most eminently distinguished above the other creatures of this world, and by which, perhaps, he partakes most of the constitution of superior natures. Now, Logic is that art. Its professed purpose, as we have observed above, is to teach us the right use of reason, both in the investigation and in the communication of TRUTH;—to inform us how to introduce clearness and good order among our IDEAS ;-10 explain the OPERATIONs of the mind which are conversant about those ideas; and by the proper exercise of which operations, we shall be least in danger of deviating into error.

The UNDERSTANDING is occupied entirely with knowledgethe end of all science is to instruct us in knowledge; and the same end is pursued by all study, whether prudential, political, moral, or mechanical. In what way soever we exert and exercise our understanding, it is to obtain some information that we did not before possess; and the design of logic, considered as an art, is to hold forth the manner of attaining that knowledge with the greatest ease and expedition.

From these views of the nature and end of Logic, it is apparent, that it claims our attention as one of the first arts to which we should apply, in our progress towards knowledge, either as the best means of fortifying or of improving the understanding. The more acute the understanding is, the inore successful wiil it be in the investigations of science. The less it is liable to err, the more certain and expeditious will be its progress in new and untried pursuits. The more we are acquainted with those sophistries which have misled other reasoners, the less liable shall we be to fall into similar mistakes. The better we understand the nature of the instrument which we employ, we may reasonably expect to be more expert and successful in its use. Every thing, then, in Logic, that does not contribute to improve the understanding, and to promote our progress in useful knowledge, deserves no attention ; but every thing, on the other hand, that promotes these ends, cannot obtain more attention than it deserves.

Though no art ever gave occasion to so much idle research and fanciful refinement as Logic; though none ever so much bewildered the human inind, and repressed every useful exertion of the understanding, as that which pretended to enlighten and improve this faculty, and to guide it in the road to truth ; though all the syllogism of the schools, after the thousand volumes that have been written on it, and after the employment of a series of ages to bring it to perfection, never enriched science

or art with one useful discovery,—we must not rashly conclude that these abuses furnish proofs of the general inutility, or insignificance, of Logic as an art.

As, then, the sophistry and absurdity with which Logic has been disgraced, are no valid objections against its use in a philosophical course of education, so neither is it to be contemned because we hear some men reason very justly without any acquaintance with its rules. There is in all mankind some natural logic, for it is one of those arts which may be learned by practice, with out the knowledge of theory.

One of the best methods of making progress in the art of reasoning, is actual practice, or the acquisition of the habit of examining a train of ideas constituting an argument; and of this branch of the art all men acquire some share by experiencemany men acquire a great deal ; but though long experience in sound reasoning may render us expert logicians, in the same manner as practice, without the knowledge of principles, may form eminent practitioners in any other art, yet this success will not justify any inference against the utility, or even the propriety of the theory. The end of all theory in the arts, is, to render us more methodical and reputable in their performance; and a knowledge of the principles on which, in this volume, the art of Logic is founded, can scarcely fail to facilitate the progress of youth in becoming good reasoners. !

Of this they may be assured, if they have sufficient candor to adınit there is such a thing as good reasoning, that there is no accomplishment or qualification any man can acquire more important than the art of reasoning well

. Whether, then, youth shall become, in life, men of speculation or men of business, in every step they take, their rational faculties must be constantly exercised; and the subject of which we now speak is calculated entirely to render them expert and successful in that exercise.

The Fifth Book, which offers a sketch of “The Philosophy of Human Knowledge," seemed a necessary Appendix to the volume; but it was not my object, in the compass of a few pages, to enter upon a subject which I intend to publish in a separate work, as a sequel to my Grammars of Rhetoric and Logic.

And, for the purpose of initiating youth in the doctrines of the Philosophy of Mind, I have constructed, on this Grammar of Logic, a Book of “ Questions and Exercises,” with a “ Key” to the same; as, in my humble judgment, no discipline is more successful in accomplishing its end, than that which reduces literature, philosophy, and science, to interlocutory discourse, conducted in the style and manner of a spirited dialogue. The ease with which the entire volume may be converted into “Dialogues on Logic and Intellectual Philosophy,” by means of its companion, the “ Book of Questions,” can only be equalled by the advantage

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