ART. IX.-Abercrombie on the Intellectual Powers. The utility of the study of metaphysical subjects has often been called in question, by men whose opinions are entitled to respect and consideration. The different ideas which have been maintained by the various writers on intellectual philosophy, and the violence with which they treat the sentiments of their predecessors and contemporaries, are certainly sufficient reasons for withholding our assent from the doctrines of any particular author, until they have been sufficiently compared and examined. But to deny that any advantages are gained by an acquaintance with the manner in which our mental operations are performed, is carrying our objections to the imperfect efforts of writers on this subject, to a very unwarrantable extent. Plain practical men often regard metaphysical disquisitions with contempt. This generally arises from the fact that such persons rarely meditate on general subjects, or on those in which they are not immediately concerned; and of course do not give them attention sufficient to be able to judge with accuracy of their importance. There is another reason for our neglect of this study, which, though perceived in a confused manner by most persons, does not fail to affect our actions. We have experienced, in numberless instances, that the things of most importance are in general understood with the greatest ease, and therefore when a subject is presented for our consideration, which is not comprehended without difficulty, we naturally dismiss it as unworthy of our attention. The truth of the last observation, however, though very general, is by no means universal. A reference to the abstruse astronomical calculations, which are indispensably necessary for the mariner, or to the subtile arguments employed by the theologian and jurist in the explanation of principles which are considered as all-important to our happiness, is sufficient to prove that facts, discovered by the most difficult analysis, or deduced by the most extensive and careful reasoning, may be of the first consequence. That the science of ideas has been cultivated by some fine scholars of the present age, among whom we may reckon this author, is a proof of the estimation in which it is held by those who are best qualified to judge, from their observations and pursuits, of its practical utility. If we consider that the several branches of the faculty of thinking, as memory, judgment, &c., are improved and strengthened by certain treatment, according to their several qualities, it is obvious that the nature and relations of each should be fully understood, before they can be improved in the highest degree. Mental philosophy is therefore a study necessary for the instructer, as well as for the scholar who would direct his mind in the proper channel to discover truths, to retain them, or to deduce from them the greatest number of important consequences. 6 Our author appears to think, that the largeness of the number of facts which have relation to mental operations, is what constitutes perfection in this study. In his Introduction he says, It is in modern times only that this science has assumed a real value, and a practical importance, under the researches of those eminent men, who have cultivated the philosophy of mind, on the principles which are acted upon in physical science: namely, a careful observation of facts, and conclusions drawn from these by the most cautious induction. The chief hindrance to the cultivation of the science on these principles, arises from the difficulty of procuring the facts, for the only field in which the mental philosopher can pursue his researches with perfect confidence is his own mind.' The manner of treating the philosophy of the human mind, considered here as proper, is not in our opinion that which is best calculated to carry it to perfection; nor is it the method pursued at present in those physical sciences, which are susceptible of being deduced from principles. That it was the mode in which they were commenced is not denied; but by slow and almost imperceptible gradations they have changed their original character, and at length approach perfection. At first, a mass of facts which had relation to a particular subject was collected, to which others were slowly added. But still these truths could no more be said to constitute a science, than the simple enunciation of the principal properties of spherical triangles could be called spherical geometry or trigonometry. It was only after the facts were compared, and VOL. XXXVI.-NO. 79. 62 shown to depend on a few general principles, from which they and many others could be readily deduced, that the science was formed. And in general the more we are able to reduce the original principles which constitute its basis, the nearer we bring it to perfection. The truth of our reasoning is exemplified in the science of hydrostatics, which is now deduced entirely from the fact, that all parts of the surface of a fluid in a quiescent state, preserve a uniform level. Formerly, a great number of experiments, more or less liable to error, was all that was known concerning it, and thousands of the most useful applications of the science were undiscovered, because no general principles were inferred, from which all possible consequences could be drawn. Mechanics, formerly, was only a description of a number of complicated machines; and as a proof of its imperfection in that state, we have only to refer to the innumerable and very expensive efforts of the greatest philosophers of those days, to discover perpetual motion, or to form a machine which should possess the power of motion in itself, continuing as long as its materials should endure. It is only of late, since the science of Mechanics has been really formed, after the powers of all machines have been deduced from a few elementary principles, that such a machine has been demonstrated to be impossible. It would therefore appear, that a science is not nearer to perfection, in proportion to the greatness of the number of isolated facts which are known concerning it, but rather to the facility with which all the truths relating to it are derived from a few first principles. It is not denied, that experimental facts are extremely useful in pursuing our researches in any branch of study; the conclusions to which we arrive, in conducting our inquiries, should be constantly compared with them. By this means, not only the falsity of the results to which we arrive may be detected, if we have reasoned incorrectly; but also those things which we have regarded as facts may, on a thorough examination, when compared with our deductions, be found to possess no reality, or to have no relation to the subject. Our remarks of course do not apply to anatomy, medicine, &c., nor to those sciences which are called descriptive for perfection in these, from the nature of things, really does depend on the number of the truths relating to them which have been observed. It is obvious to any mind, which considers the subject, that there can be no general principles in such studies, from which facts concerning them may be inferred with any degree of certainty. Dr. Abercrombie pursues the course which, in his Introduction, he considers as most proper for investigations of the kind under consideration. His method is much the same as that of Reid and Stewart. Many facts are related, which are considered as being experimentally known and understood, and the more immediate consequences are drawn from them. The subject, when discussed in this manner, is susceptible of an almost infinite extension, which Reid, Stewart and some others seem to have fully comprehended. It must be acknowledged that, in some respects, we are less liable to error in pursuing the method of Abercrombie, than when that of which we have spoken is followed for if the facts which we relate are well examined, and none admitted that are unconnected with the subject, or whose reality is not fully determined, they furnish so many points, on which our minds may rest; and if we do deviate from the truth in the immediate inferences which are drawn from them, we seldom err so grossly, as when we follow out the consequences of a few principles to a great extent. But then, as we have already intimated, many of the most important truths, which depend on a great number of these facts, can never be discovered. Abercrombie regards the deficiency of facts as the chief difficulty in conducting metaphysical researches. We think, on the contrary, that if the innumerable facts which have been brought forward in relation to intellectual philosophy, by the host of writers from Aristotle to this day, do not furnish sufficient materials to conduct our inquiries on this subject, it is time for us to relinquish such barren and unprofitable speculations. Our own opinion is, that the science is sufficiently rich in isolated facts; that no more or very few more are wanted, in order that it may be completely developed in all its branches. It is merely necessary that they should be compared, their relations traced, and that all the operations of the mind should be shown to depend on certain faculties, which can be decomposed into no others more simple. The work under consideration seems, however, not to be intended as an elementary treatise, but rather as a collection of observations on the mind, which may be read by every one, and understood without much meditation. The style is popular, and of course we are not to expect that careful regard to system, and those close and rigid arguments, which are appreciated only by such as have formed habits of attention and nice discrimination. The reader must constantly keep in mind, that the author does not profess to confine himself to those subjects which are usually understood to belong to intellectual philosophy, nor even to examine all those which do appertain to that science; but to show the results of certain inquiries which he institutes concerning the intellectual powers and the investigation of truth. It will be readily perceived, that inquiries concerning the investigation of truth belong to the science of logic, or the science of the deduction of ideas: indeed they form that science. These last inquiries, pursued under the heads of Reason and Medical Science, occupy more than half the volume, even if we deduct from them the occasional discussions, which are generally ranged under the science of mental philosophy. Some persons speak of this treatise as elements of the philosophy of the human mind.' The following is the language of the British Critic. In the very moderate compass of one volume, he has placed within the reach of the student as much sound metaphysical lore as any human being need give, and wish to possess, unless he aspires to very high distinction in that peculiar line of investigation. He has divested his researches of all the frivolous trumpery, in which the philosophers of former days were often in the habit of disguising their ambitious poverty? The reviewer here gives the author credit for much more than he claims himself. We strongly suspect that Dr. Abercrombie would agree with us in asserting, that some of the most important branches of logic, and of the philosophy of the human mind, are not discussed, nor indeed hinted at in this work; and that it is in reality what it professes to be, certain inquiries concerning the intellectual powers, and the investigation of truth. We are moreover by no means certain, that the motive which influenced the writer to attend to these researches, was not the desire to give to others of his profession a method, by which their medical investigations might be conducted with ease and accuracy. We believe, in fact, that this was the case, and that some of the principal outlines of the science of the human intellect were given merely as preliminaries, necessary before |