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Hamilton it is a study of thoughts abstract from their connection with things-the rationale of the conditions under which we must think about anything. The discussion of the subject here involved respecting the proper province of logic will be referred to further on.

We have no need to certify the superiority of Sir William Hamilton as a philosophical writer. Doubtless there are few who, however they may dissent from some of his doctrines, will deny that he occupies the most influential position, within his chosen sphere, of any writer of the present age. His extraordinary erudition, his familiar acquaintance with all that is best in the best writers of all times and nations, his thorough command of his own vast resources, his discriminating judgment preventing any subserviency to the valuable opinions of which he was yet ready to avail himself, and the clearness, precision, and force with which he conveys his doctrines, compel the recognition of his pre-eminence among the philosophic thinkers of the present century.

There are several treatises of his on logic, which have been published either in separate dissertations, or in connection with his philosophical discussions. There are also fragments showing that he meditated a great work on the subject, which would scarcely have been inferior to any since the days of Aristotle. This project, like others of our author, was never consummated.

It is with lively satisfaction that we hail the appearance of the volume before us, and its prompt republication in this country in a form so handsome and convenient. The lectures are thirty-five in number. They were delivered to the undergraduates of the University, and are a model of instruction by means of lectures. Of course, there are many abstruse discussions and speculations which could not be contained in such a series. Of the lectures the first four are introductory, and contain the definition of logic, a statement of its utility, and its divisions. The remainder of the course is in two parts-Pure or Formal Logic, and Modified Logic. The former the author regards as the exclusively legitimate province of logical study, and on this there are twenty-two lectures. On the latter there are only nine, and these are avowedly supplementary. After the introduction there are two lectures embracing a statement

of the axioms and postulates of logic, accompanied by a copious historical and critical commentary. These two lectures are a great improvement on most of the British manuals on logic, inasmuch as in the latter these first principles are in a certain sort taken for granted, though not expressly stated; thus confusing the student in the beginning of his study by vague uncertainties.

The next six lectures contain an analysis, partly formal and partly psychological; of Conception. These lectures are perhaps, as a whole, the most valuable, certainly the most interesting, in the volume. The remaining lectures, before coming to the division of modified logic, are devoted to the process of propositions and syllogisms, and to the doctrine of methodology.

The appendix occupies nearly a quarter of the volume, and contains a more thorough discussion of certain recondite principles, and especially of doctrines relating to logical processes.

There has been much controversy as to the proper objectmatter of logic, and especially as to whether it is a science or an art; a question all the more unlikely to be settled from the total want of agreement as to the limitation of these terms in their relation to each other. Plato and the Platonists regarded it as a science; but with them it covered nearly all the ground occupied by metaphysics. Aristotle himself does not define it; but many of his ancient followers, as well as some since the revival of letters, deny it to be either science or art. The Stoics generally, as also the Arabian and Latin schoolmen, viewed it as a science. The Ramists, many of the later Aristotelians, and a majority of the Cartesians, maintained it to be an art; though a party was found who regarded it as both science and art. In Germany, since Leibnitz, it has been almost universally regarded as a science. Sir William Hamilton remarks that, so far as logic is concerned, the decision is not of the very smallest import. "The controversy was, in fact, only about what was properly an art and what was properly a science; and as men attached one meaning or another to these terms, so did they affirm logic to be an art or a science, or both, or neither." Whately considers it in its most extensive sense to be "the science and also the art of reasoning." But he evidently confuses the distinction of science theoretical and science practical, with the distinction of science and art.

Hamilton regards logic, as to its genus, a science; not, however, intending by this "to give it more than the general denomination of a branch of knowledge." He defines it as "the Science of the Laws of Thought as Thought." To an explication of this definition the most of two lectures is devoted. There is a full and clear statement of the meaning, history, and synonyms of the word logic, also extended remarks on its genus as a science. Then follow the author's views of the province of logic, its object-matter, or what is meant by saying it is conversant about the laws of thought as thought. Thought, in its wider meaning, is used to denote every cognitive act whatever. With Descartes and his disciples it embraces every mental modification of which we are conscious, including the feelings, volitions, and desires. "In the more limited meaning it denotes only the acts of the understanding properly so called; that is, of the faculty of comparison, or that which is distinguished as the elaborative or discursive faculty." In this latter signification the term is used in these lectures. Thus logic, in its pure state, has nothing directly to do with the rude materials of knowledge, other than to suppose them in possession. It takes no account of memory, imagination, or the laws of association; nor even of the laws of intelligence as given in the regulative faculty. Excluding these, we have for thought proper the following statement:

All thought is a comparison, a recognition of similarity or difference; a conjunction or disjunction; in other words, a synthesis or analysis of its objects. In conception, that is, in the formation of concepts, (or general notions,) it compares, disjoins, or conjoins attributes; in an act of judgment it compares, disjoins, or conjoins concepts; in reasoning it compares, disjoins, or conjoins judg ments. In each step of this process there is one essential element: to think, to compare, to conjoin, or disjoin, it is necessary to recognize one thing through or under another; and therefore, in defining thought proper, we may either define it as an act of comparison or as a recognition of one notion in or under another. It is in performing this act of thinking a thing under a general notion that we are said to understand or comprehend it. For example: an object is presented, say a book; this object determines an impression, and I am even conscious of the impression, but without recognizing to myself what the thing is; in that case there is only a perception, and not properly a thought. But suppose I do recognize it for what it is, in other words, compare it with and reduce it under a certain concept class, or complement

of attributes, which I call book; in that case there is more than perception-there is a thought.-P. 10.

So much for thought proper. By thought, as thought, is meant the form of thought as distinguished from the object thought of. "When I think that the book before me is a folio, the matter of this thought is book and folio; the form of it is a judgment." It is by neglecting this discrimination that much confusion has existed as to the legitimate province of logic, and in the prosecution of its study.

By the laws of thought as thought, or the formal laws of thought, logic discriminates its field from that of other sciences. Psychology as well as logic is conversant about the phenomena of formal thought. By speculative analysis the phenomena of the formal or subjective phases of thought may be separated into two kinds. They are either the contingent, that is, such as may or may not appear; or they are such as are necessary, that is, such as cannot but appear. These phenomena, considered as manifestations in general, belong to the science of empirical or historical Psychology. But when separated into necessary or contingent forms of thought, the former becomes the peculiar object-matter of logic.

When we say that logic is the science of the necessary powers of thought, this quality of necessity implies four conditions. (a.) It is subjectively, not objectively determined. (b.) It is original and not acquired. For if acquired, there must have been a time when it did not exist, and thus we could conceive the possibility of its not existing now, which vitiates its necessity. (c.) It must be universal; that is, it always necessitates, otherwise it would be contingent. (d.) It is a law; "for a law is that which applies to all cases without exception, and from which a deviation is ever and everywhere impossible, or at least unallowed." Logic is thus distinguished from the other philosophical sciences as the science of the necessary forms of thought.

As has been all along implied, our author differs from many of his predecessors respecting the utility of logic. He has a thorough examination of the uses claimed for it by a great variety of writers, and a brief but conclusive discussion of the principles on which they are severally based. The errors in general concerning the utilities of logic arise from the errors

concerning its object-matter. Hence, from the fact that it was supposed to have to do with the matter of thought, followed the opinion that it was an instrument of scientific discovery. Thus it was long styled the art of arts and science of sciences. Many works on the subject had the fanciful titles, implying this notion, of Via ad Veritatem, Cynosura Veritatis, Caput et Apex Philosophia, Heuristica sive Introductio ad Artem Inveniendi, etc. It was held by many to be the infallible corrector of our intellectual vices and the invigorator of our intellectual imbecility. Hence treatises designated as The Lighthouse of the Intellect, The Medicine of the Mind, The Art of Thinking, etc., were common. Our author, while admitting that there is here a mixture of truth with error, thinks that logic may be styled an instrument or organon of the other sciences in the sense that it may determine their scientific form; that is, may be a formal instrument. It cannot properly be denominated an art of discovery, "for discovery or invention is not to be taught by rules." It evolves nothing new, and does not amplify our knowledge of facts. "Logic is thus not creative; it is only plastic, only formative, in relation to our knowledge." So, too, it is a medicine of the mind only so far as it corrects formal errors, while material errors lie beyond its reach. An extension of any science through logic is absolutely impossible. It only enables us to render what is already obtained more intelligible by analysis and arrangement. It is "only the negative condition of truth." It is positively beneficial in that it gives, to a certain extent, dominion over our thoughts, supplies in part the criterion of truth from error, invigorates the understanding, and affords a scientific nomenclature.

On the division of logic Hamilton is very full and clear. His views are many of them peculiar to himself. Logic is divided either according to its kinds or its parts. Considered by relation to the mind, it is viewed as Objective and Subjective, or Systematic and Habitual. "By objective or systematic logic is meant that complement of doctrines of which logic is made up; by subjective or habitual logic is meant the speculative knowledge of those doctrines which any individual, as Socrates, Plato, Aristotle, etc., may possess, and the practical dexterity with which he is able to apply them."

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