MAGAZINE JANUARY, 1817. ART. I.-Philosophical Essays; to which are subjoined, Copious Notes, Critical and Explanatory, and a Supplementary Narrative; with an Appendix. By James Ogilvie. Philadelphia. 1816. 8vo. pp. 413. ESSAY II.-On the Nature, Extent, and Limits of Human Knowledge, so far as it is founded on the Relation of Cause and Effect, and concerns Mind and Matter.-As it was also a part of Locke's design to inquire into the original, certainty, and extent of human knowledge,'* Mr. Ogilvie very naturally begins his inquiries by examining that philosopher's account of the sources from which is derived whatever we know of the intellectual, and of the material world. He seems not to be aware, however, that the most important part of his criticism was rendered superfluous by the labours of the later metaphysical writers; and that sensation and consciousness,—instead of sensation and reflection, are now universally considered as the two appropriate words to express those feelings which we experience, by corporal impression, in the one case, and by intellectual energy, in the other. But the author before us goes further; and in his eagerness to show the imprecision of Locke in drawing this single line of demarkation, he has himself overrun and trampled under foot almost all the other nice boundaries of philosophical language which have been pointed out, not only by that metaphysician, but by the most acute and discriminating of his successors. When he has once established the claims of consciousness to a part in the origination of our ideas, he is for assigning to it an office, which, in our opinion, is much beyond its capabilities, the office, namely, of furnishing us with the knowledge, not only of all intellectual phenomena, but of whatever takes place in the material world. Now to us it is perfectly apparent, in the first place, that mere consciousness, or mere sensation, could never advance us * Introduction to the Essay on Human Understanding. § 2. MAT very far in the philosophy either of mind, or of matter. There must be something besides the passive experience of those feelings which physical and intellectual phenomena are respectively calculated to produce. We may be sensible of outward impressions, and conscious of internal energies, without attempting to deduce a single conclusion respecting the peculiar subjects about which the mind is employed; and it has accordingly been remarked by a countryman of Mr. Ogilvie's, that observation in the former case, and reflection in the latter, are the two analagous media through which we carry on our investigations into the phenomena of the material, and of the intellectual universe.* While we acknowledge the inaccuracy of Locke, therefore, in considering reflection as an original source of human knowledge, we must contend, on the other hand, that it has still a very important secondary function in prosecuting the philosophy of the mind. Our author himself seems, in one place, to admit about half of this proposition; but the admission is rendered nugatory by his defining reflection to be a concentration of consciousness,'-a definition which we consider as either altogether incomprehensible, or as conveying a signification which at once destroys the boundaries of scientific phraseology. But, in the second place, Mr. Ogilvie contrives to make consciousness supersede the office,-not only of reflection,—but of sensation also. Whenever the subject is introduced he almost invariably speaks of our consciousness of impressions from external matter; and indeed he makes it one of his formal principia, that our language and of course our ideas, as they regard the philosophy of the human mind, will be more precise, if we consider whatever is known or knowable (an awkward term, which our author uses a great deal too often) as proceeding from our consciousness, first, of impressions from external objects, and secondly, of the internal energies called into action by these impressions.'-To us it does most certainly appear, that there is very little 'precision' in all this:—and we confess we are somewhat at a loss to conceive how Mr. Ogilvie should think he contributed to the clearness of philosophical language, by confounding the terms, which mark the separation between the two great inlets of human knowledge. In the looseness of colloquial speech, it is true, we make use of the * Stewart's Philosophical Essays, p. 66, Philadelphia edition. See, on the same subject, Reid's First Essay on the Intellectual Powers, chap. v. 'Reflection (says the latter philosopher) ought to be distinguished from consciousness, with which it is too often confounded, even by Mr. Locke. All men are conscious of the operations of their own minds, at all times, while they are awake; but there are few who reflect upon them, or make them objects of thought,' &c. phrase-impression on the mind; but surely no philosopher has ever adopted such language, while professedly endeavouring to develop the mode in which mind converses with matter; and it is obvious, indeed, upon a moment's consideration, that all external objects can only be impressed upon the material organs of our bodies. It is quite indisputable, we apprehend, that the dominion of consciousness is merely coextensive with the boundaries of the human mind,-and that the only way in which it can be said to have any sort of connexion with outward existences, is by its cognizance of that intellectual faculty, which the impression of those existences upon our corporeal organs is calculated to bring into action. In few words, we are sensible of impressions, and conscious of sensation.* very sum and essence But consciousness, in Mr. Ogilvie's system of mental philosophy, is even something more than the faculty by which we acquire all our knowledge both of physical and of intellectual phenomena:-it is, under various shapes, the of that knowledge. He almost uniformly takes the pains to use the phrase modifications of consciousness' as synonymous with the subjects of consciousness;' evidently implying, according to the received signification of the words, that all the knowledge we have of the phenomena which come within our cognizance, is merely a peculiar state or condition of that feeling which the presence of those phenomena are the occasions of producing:-and as he had before told us, that the feeling in question was produced by external, as well as by internal, phenomena, it follows that, agreeably to his own doctrine, whatever we know either about mind, or about matter is-not a knowledge of actual existences-but simply a modification of the faculty which is conversant with those existences. To state the proposition in fewer words, there is no such thing as a subject of consciousness, independently of consciousness itself. Under a little mutation, this doctrine is nothing less than the scepticism of Hume; the word consciousness being used by the author before us in so enlarged a signification as to embrace, not only all the terms by which philosophers distinguish the feeling excited by our intellectual operations, but those also which have been customarily used to denominate the effects of material impression. Whether Mr. Ogilvie was aware that his language involved this conclusion, we are hardly able to determine. We should be very sorry to extort a meaning from the language * We suppose our author has been led astray by following too implicitly the example of Hume's 'freedom' in the employment of language. See the Inquiry concerning Human Understanding, Sec. II. See also Reid's Essay I. on the Intellectual Powers, chap. v.; Essay VI. chap. v.; et passim. 6 of any writer; and we readily acknowledge, that the forms of expression in the Essay under consideration, are not absolutely uniform. We shall have occasion to show, however, that in other instances our author has adopted more extensively than perhaps any other philosophical essayist, the metaphysical doctrines of what he calls the arch-sceptic;' and we have often been inclined to believe that, in this case also, he has retained the principles, while he has discarded the language, of those speculations concerning independent existences, which have so much contributed to the celebrity of Hume. The phraseology of our author is in general so vague and indeterminate, that we are obliged to collate all the parts of his Essay, before we can be assured of having understood him aright. The fact is to be attributed, in a great measure, we suppose, to the extreme haste and consequent inattention with which Mr. Ogilvie has chosen to put his observations together. The composition of philosophical essays should never be considered as a transient business;-and the writer who thinks of acquiring extensive and permanent celebrity' must do something more than merely to suspend, for a short time, an itinerant occupation,-throw together the crude materials of a book,-send them to press as he goes along,and then resume his wonted orbit as if he had suffered no retardation. A book is not to be dropped in this way. He But there are propositions, of which the occurrence is so frequent as to render misapprehension almost impossible. Of this sort is the principle laid down in our author's definition of human knowledge. It is (says he, and we are assured that it is said neither lightly, nor rashly') the arrangement of the various subjects or modifications of consciousness, in the order of cause and effect: Or a coincidence betwixt the order, in which the various subjects and modifications of consciousness, is (are) concatenated in the mind, and that in which the corresponding phenomena, are connected according to the relation of cause and effect.' He has subjoined another definition of the same import,—but differing a little in the forms of expression. was anxious to prevent misconception; for the principle here inculcated lies at the very foundation, and is ramified through the whole superstructure, of the Essay. We think, however, that the language we have already quoted is sufficiently explicit;—and we may repeat in a few words that, according to Mr. Ogilvie, our knowledge is nothing more than the right arrangement of ideas according to the order of cause and effect. We dissent from the definition altogether. It does not, in our opinion, comprehend at all the notion which is commonly affixed to the term; and it would be difficult, at first sight, to conceive how our author should define knowledge itself, to consist merely in |