of ideas, concerning the use and abuse of terms, and concerning the extent and limits of our intellectual powers, are well known by those conversant with the philosophy of mind, to display many new doctrines, and to place their author among the most profound thinkers. Mr. LockE differed from DES CARTES with respect to the origin of our ideas. The latter thought some of them were innate; the former maintained that there are no innate ideas, and that they are all derived from two sources, sensation and reflection. DES CARTES supposed that the essence of mind consists in thought, and that of matter in extension; while LOCKE be lieved that the real essence of both is beyond the reach of human knowledge. The British philosopher explained more distinctly than any one had done before him, the operations of the mind in classing the various objects of thought, and reducing them to genera and species. He was the first who distinguished in substances what he calls the nominal essence, or that generic character, and specific difference, which may be expressed by a definition, from the real essence, or internal constitution, which he supposed could not be known; and who, by means of this distinction, pointed out the way of bringing to an issue those subtle disputes, particularly the controversy between the. Nominalists and Realists, which had puzzled the schoolmen for ages. He showed, more satisfactorily than preceding inquirers, how we form abstract and general notions, and the use and necessity of them in reasoning. He first expressed the distinction between primary and secondary qualities, though the ideas implied in this distinction seem to have been in some measure understood by DES CARTES. And, finally, Mr. LOCKE had much merit peculiar to himself, in exhibiting the ambiguity of words, and by this means solving many difficult

questions which had tortured the wits of former metaphysicians."

From the date of this great man's work, the old Ontology and Logic have declined. The philosophy of mind has assumed a more simple, popular, and intelligible aspect. And although it has been since made to appear probable, that some of the doctrines which he taught are erroneous, especially the theory of perception, which he adopted from his predecessors; yet that he contributed more than any other individual of modern times to develope the nature and operations of the human mind, and to introduce a more rational and correct mode of philosophising on this subject than had before prevailed, seems to be generally admitted.

Not long before Mr. LockE published his celebrated Essay, Father MALEBRANCHE, a learned and acute metaphysician of France, in a work en→ titled Recherche de la Verité, or Inquiry after Truth, published a doctrine which soon led to sin gular consequences. He laid it down as a prin ciple, which, indeed, had then been admitted by all preceding philosophers, that we do not per ceive external objects immediately, but by means of images, or ideas of them present to the mind, In order to account for the production of these ideas in the mind, he maintained that the soul of man is united with a being possessed of all perfection, who has in himself the ideas of every created being; and therefore that we see all things in God. MALEBRANCHE Was sensible that this system left no evidence of the existence of a material world for if the mind sees all things in God; or if the Divine ideas alone are perceived by us, we cannot be certain that the various forms of matter around us exist, since the ideas in the Eternal Mind were

See Essay on the Human Understanding, passim; and REID's Essays on the Intellectual Powers of Man, vol. i. Essay 2. chap. ix.

the same before any creature was made. This consequence he candidly acknowledged, and maintained that the only evidence we have of the existence of a material world, is derived from Revelation, which assures us that God created the heavens and the earth, and that the Word was made flesh. This doctrine was vigorously and ingeniously opposed by its author's countryman and cotemporary, ANTHONY ARNAULD, Doctor of the Sorbonne. But though the latter succeeded in showing the weakness and fallacy of the reasonings which he attacked, he was not equally success+ ful in establishing a consistent and satisfactory theory of his own. The system of MALEBRANCHE, however, notwithstanding its visionary character, was warmly espoused by Mr. NORRIS, an English divine, who, in 1701, published a large and laborious work, designed to explain, support, and extend it. He went beyond the French philosopher, on the subject of the material world; for although he maintained the probability of its existence, he denied out having any evidence absolutely decisive that this is the fact.

In 1710 a doctrine still more singular and dar ing was announced by GEORGE BERKELEY, a philosopher of Ireland, and afterwards Bishop of Cloyne. This gentleman, equally distinguished for the penetration and comprehensiveness of his mind, the extent of his learning, and the eminence of his virtues, denied the existence of a material world; contending that what are usually called sensible objects without us, are only ideas in the mind; that there is nothing in the universe but spirits, and ideas, or images subsisting in, and perceived by them. He differed from Mr. Locke in several other respects besides this. He discarded reflection as a source of ideas; he divided the objects of human knowledge into two kinds, ideas and nơ

tions. The first, according to him, are presented to us by our five senses; they have no existence when they are not perceived, and exist only in the minds of those who perceive them. The second kind of objects he supposed to comprehend spirits, their acts, and the relations and habitudes of things: of these, he contended, we have notions but not ideas. But of all the opinions taught by this great and good man, none have rendered him more famous, than his denial that those prototypes of our ideas, usually called material objects, have any real existence; and contending that all the varied beauties of creation which we behold, are nothing more than fancies or images impressed on the mind for wise purposes, by the omnipotent Creator.

Although, as was before observed, Father MALEBRANCHE shrunk from this bold conclusion of BERKELEY, yet he was aware that his reasonings led to it: and, indeed, his work may be said to contain a large portion of the arguments afterwards adopted by the acute and learned Bishop, in their full force. But to BERKELEY is due the honour of having first openly espoused this doctrine, so contradictory to all our feelings and senses; of defending it upon a more formal and extensive plan than any of his predecessors; and of giving new and ingenious views of the subject."

About three years after the Bishop's first publication on this subject, ARTHUR COLLIER, an English clergyman, in his book, called Clavis Universalis, or a New Inquiry after Truth, endeavoured

See Principles of Human Knowledge. Dublin, 1710.

d M. DUTENS, who is anxious to find among the ancients every invention and doctrine to which the moderns lay claim, quotes the following passage, in which something like the Berkleian doctrine is plainly alluded 10. Γινεται κατ' αυτόν, των ονλων κριτηριον ο άνθρωπος· πανία τοίνον, yog 706 Φαινόμενα τοις ανθρωποις, και εξλιν, τα δε μηδενι των ανθρωπων φαινομενα, oude ecly. Sext. Empiric. Pyrrhon. Hypotypos. lib. i. sect. 219. See Regherches sur l'Origine de Decouvertes, &c. tom. i. 53.

to demonstrate the non-existence and impossibility of an external world. The arguments which he adduced in support of his cause are the same in substance with those used by Dr. BERKELEY, though the author says nothing of the work of that celebrated metaphysician, and does not appear to have seen it.

There was only one step more which was left for the most daring metaphysical revolutionists to take, viz. to deny the existence of a spiritual as well as of a material world. This step was at length ventured upon by Mr. HUME, a sceptical metaphysician of Great-Britain, whose acuteness and ingenuity are well known. Adopting Mr. LOCKE's, and Bishop BERKELEY'S opinion, that all the immediate objects of human knowledge are ideas in the mind, he traced the consequences of this principle to their utmost extent, and contended that there is neither matter nor mind in the universe! That what we call body is only an assemblage of sensations; and what we call mind only an assemblage of thoughts, passions, and emotions, without any subject. On the opposition in which the doctrines of the Irish Ecclesiastic and the Scottish historian stand to the common sense, and all the spontaneous and the deepest impressions of mankind, it is needless to remark. Their authors were sensible of this, and it is probable did not, in moments of sober reflection, believe their own speculations. Certain it is, they both acknow

e The universal scepticism to which the sophistry of Mr. HUME leads, or rather which it directly embraces, cannot, with propriety, be considered here. Nor is it necessary. The extravagance and the mischievous tendency, especially of some of his opinions, seem, at present, to be acknowledged by all, excepting the desperate few, who are ready calmly to resign all principle, and all belief. The character of his philosophy, "falsely so called," has been exposed with great beauty of rhetoric, by Dr. BEATTIE, in his Essay on Truth; and, with great force of reasoning, by Dr. REID, in his Inquiry into the Human Mind, and his Essays on the Intellectual and Active Powers of Man.