in the various branches of science, the established creed of the age he lives in. How inconsiderable would have been the progress of mathematicians, in their more abstruse speculations, without the aid of the algebraical notation; and to what sublime discoveries have they been led by this beautiful contrivance, which, by relieving the memory of the effort necessary for recollecting the steps of a long investigation, has enabled them to prosecute an infinite variety of inquiries, to which the unassisted powers of the human mind would have been altogether unequal! In the other sciences, it is true, we have seldom or never occasion to follow out such long chains of consequences as in mathematics; but in these sciences, if the chain of investigation be shorter, it is far more difficult to make the transition from one link to another; and it is only by dwelling long on our ideas, and rendering them perfectly familiar to us, that such transitions can, in most instances, be made with safety. In morals and politics, when we advance a step beyond those elementary truths which are daily presented to us in books or conversation, there is no method of rendering our conclusions familiar to us, but by committing them to writing, and making them frequently the subjects of our meditation. When we have once done so, these conclusions become elementary truths with respect to us and we may advance from them with confidence to others which are more remote, and which are far beyond the reach of vulgar discovery. By following such a plan, we can hardly fail to have our industry rewarded in due time by some important improvement; and it is only by such a plan, that we can reasonably hope to extend considerably the boundaries of human knowledge. I do not say that these habits of study are equally favorable to brilliancy of conversation. On the contrary, I believe that those men who possess this accomplishment in the highest degree, are such as do not advance beyond elementary truths; or rather, perhaps, who advance only a single step beyond them; that is, who think a little more deeply than the vulgar, but whose conclusions are not so far removed from common opinions, as to render it necessary for them, when called upon to defend them, to exhaust the patience of their hearers, by stating a long train of intermediate ideas. They who have pushed their inquiries much farther than the common systems of their times, and have rendered familiar to their own minds the intermediate steps by which they have been led to their conclusions, are too apt to conceive other men to be in the same situation with themselves; and when they mean to instruct are mortified to find that they are only regarded as paradoxical and visionary. It is but rarely we find a man of very splendid and various conversation to be possessed of a profound judgment, or of great originality of genius.

Nor is it merely to the philosopher, who wishes to distinguish himself by his discoveries, that writing affords an useful instrument of study. Important assistance may be derived from it by all those

who wish to impress on their minds the investigations which occur to them in the course of their reading; for although writing may weaken, as I already acknowledged it does, a memory for detached observations, or for insulated facts, it will be found the only effectual method of fixing in it permanently, those acquisitions which involve long processes of reasoning.

When we are employed in inquiries of our own, the conclusions which we form make a much deeper and more lasting impression on the memory, than any knowledge which we imbibe passively from another. This is undoubtedly owing, in part, to the effect which the ardor of discovery has, in rousing the activity of the mind, and in fixing its attention; but I apprehend it is chiefly to be ascribed to this, that when we follow out a train of thinking of our own, our ideas are arranged in that order which is most agreeable to our prevailing habits of association. The only method of putting our acquired knowledge on a level, in this respect, with our original speculations, is, after making ourselves acquainted with our author's ideas, to study the subject over again in our own way; to pause, from time to time, in the course of our reading, in order to consider what we have gained; to recollect what the propositions are, which the author wishes to establish, and to examine the different proofs which he employs to support them. In making such an experiment, we commonly find, that the different steps of the process arrange themselves in our minds, in a manner different from that in which the author has stated them; and that, while his argument seems, in some places, obscure, from its conciseness, it is tedious in others, from being unnecessarily expanded. When we have reduced the reasoning to that form which appears to ourselves to be the most natural and satisfactory, we may conclude with certainty, not that this form is better in itself than another, but that it is the best adapted to our memory. Such reasonings, therefore, as we have occasion frequently to apply, either in the business of life, or in the course of our studies, it is of importance to us to commit to writing, in a language and in an order of our own; and if, at any time, we find it necessary to refresh our recollection on the subject, to have recourse to our own composition, in preference to that of any other author.

That the plan of reading which is commonly followed is very different from that which I have been recommending, will not be disputed. Most people read merely to pass an idle hour, or to please themselves with the idea of employment, while their indolence prevents them from any active exertion; and a considerable number with a view to the display which they are afterwards to make of their literary acquisitions. From whichsoever of these motives a person is led to the perusal of books, it is hardly possible that he can derive from them any material advantage. If he reads merely from indolence, the ideas which pass through his mind will probably leave little or no impression; and if he reads from vanity, he will be more

anxious to select striking particulars in the matter or expression, than to seize the spirit and scope of the author's reasoning, or to examine how far he has made any additio is to the stock of useful and solid knowledge. "Though it is scarce possible," says Dr. Butler, (see the preface to his sermons,) " to avoid judging, in some way or other, of almost every thing which offers itself to one's thoughts, yet it is certain that many persons, from different causes, never exercise their judgment upon what comes before them, in such a manner as to be able to determine how far it be conclusive. They are perhaps entertained with some things, not so with others; they like, and they dislike; but whether that which is proposed to be made out, be really made out or not; whether a matter be stated according to the real truth of the case, seems, to the generality of people, a circumstance of little or no importance. Arguments are often wanted for some accidental purpose; but proof, as such, is what they never want, for their own satisfaction of mind, or conduct in life. Not to mention the multitudes who read merely for the sake of talking, or to qualify themselves for the world, or some such kind of reasons, there are even of the few who read for their own entertainment, and have a real curiosity to see what is said, several, which is astonishing, who have no sort of curiosity to see what is true: I say curiosity, because it is too obvious to be mentioned how much that religious and sacred attention which is due to truth, and to the important question, what is the rule of life, is lost out of the world.

"For the sake of this whole class of readers, for they are of different capacities, different kinds, and get into this way from different occasions, I have often wished that it had been the custom to lay before people nothing in matters of argument but premises, and leave them to draw conclusions themselves; which, although it could not be done in all cases, might in many.

"The great number of books and papers of amusement, which, of one kind or another, daily come in one's way, have in part occasioned, and most perfectly fall in with and humor this idle way of reading and considering things. By this means, time, even in solitude, is happily got rid of without the pain of attention; neither is any part of it more put to the account of idleness, (one can scarce forbear saying, is spent with less thought,) than great part of that which is spent in reading."

If the plan of study which I formerly described were adopted, it would undoubtedly diminish very much the number of books which it would be possible to turn over; but I am convinced that it would add greatly to the stock of useful and solid knowledge; and by rendering our acquired ideas in some measure our own, would give us a more ready and practical command of them: not to mention, that if we are possessed of any inventive powers, such exercises would continually furnish them with an opportunity of displaying themselves upon all the different subjects which may pass under our review.

This

}and!

Nothing, in truth, has such a tendency to weaken, not only the powers of invention, but the intellectual powers in general, as a habit of extensive and various reading, without reflection. The activity and force of the mind are gradually impaired, in consequence of disuse; and not unfrequently all our principles and opinions come to be lost, in the infinite multiplicity and discordancy of our acquired ideas.

By confining our ambition to pursue the truth with modesty and candor, and learning to value our acquisitions only as far as they contribute to make us wiser and happier, we may perhaps be obliged to sacrifice the temporary admiration of the common dispensers of literary fame; but we may rest assured, that it is in this way only we can hope to make real progress in knowledge, or to enrich the world with useful inventions.

"It requires courage, indeed," as Helvetius has remarked, "to remain ignorant of those useless subjects which are generally valued;" but it is a courage necessary to men who either love the truth, or who aspire to establish a permanent reputation.

SECTION VI.

Continuation of the same Subject.-Of Artificial Memory. By an artificial memory is meant, a method of connecting in the mind, things difficult to be remembered, with things easily remembered; so as to enable it to retain, and to recollect the former, by means of the latter. For this purpose, various contrivances have been proposed, but I think the foregoing definition applies to all of them.

Some sorts of artificial memory are intended to assist the natural powers of the human mind on particular occasions, which require a more than ordinary effort of recollection; for example, to assist a public speaker to recollect the arrangement of a long discourse. Others have been devised with a view to enable us to extend the circle of our acquired knowledge, and to give us a more ready command of all the various particulars of our information.

The topical memory so much celebrated among the ancient rhetoricians, comes under the former description.

I already remarked, the effect of sensible objects in recalling to the mind the ideas with which it happened to be occupied, at the time when these objects were formerly perceived. In travelling along a road, the sight of the more remarkable scenes we meet with, frequently puts us in mind of the subjects we were thinking or talking of when we last saw them. Such facts, which are perfectly familiar even to the vulgar, might very naturally suggest the possi bility of assisting the memory, by establishing a connexion between the ideas we wish to remember, and certain sensible objects, which

have been found from experience to make a permanent impression on the mind.* I have been told of a young woman, in a very low rank of life, who contrived a method of committing to memory the sermons which she was accustomed to hear, by fixing her attention, during the different heads of the discourse, on different compartments of the roof of the church, in such a manner, as that when she afterwards saw the roof, or recollected the order in which its compartments were disposed, she recollected the method which the preacher had observed in treating his subject. This contrivance was perfectly analogous to the topical memory of the ancients; an art which, whatever be the opinion we entertain of its use, is certainly entitled, in a high degree, to the praise of ingenuity.

Suppose that I were to fix in my memory the different apartments in some very large building, and that I had accustomed myself to think of these apartments always in the same invariable order. Suppose farther, that in preparing myself for a public discourse, in which I had occasion to treat of a great variety of particulars, I was anxious to fix in my memory the order I proposed to observe in the communication of my ideas. It is evident, that by a proper division of my subject into heads, and by connecting each head with a particular apartment, (which I could easily do, by conceiving myself to be sitting in the apartment while I was studying the part of my discourse I meant to connect with it,) the habitual order in which these apartments occurred to my thoughts, would present to me, in their proper arrangement, and without any effort on my part, the ideas of which I was to treat. It is also obvious, that a very little practice would enable me to avail myself of this contrivance, without any embarrassment or distraction of my attention.t

As to the utility of this art, it appears to me to depend entirely on the particular object which we suppose the speaker to have in view; whether, as was too often the case with the ancient rhetoricians, to bewilder a judge, and to silence an adversary; or fairly and candidly to lead an audience to the truth. On the former supposition, nothing can possibly give an orator a greater superiority, than the possession of a secret which, while it enables him to express himself with facility and the appearance of method, puts it in his power, at the same time, to dispose his arguments and his facts

"Cum in loca aliqua post tempus reversi sumus, non ipsa agnoscimus tantum, sed etiam, quæ in his fecerimus, reminiscimur, personæque subeunt, nonnunquam tacitæ quoque cogitationes in mentem revertuntur. Nata est igitur, ut in pleris. que, ars ab experimento."--Quinct. Inst. Orat. lib. xi. cap. 2.

In so far as it was the object of this species of artificial memory to assist an orator in recollecting the plan and arrangement of his discourse, the accounts of it which are given by the ancient rhetoricians are abundantly satisfactory. It appears, however, that its use was more extensive; and that it was so contrived, as to facilitate the recollection of a premeditated composition. In what manner this was done, it is not easy to conjecture from the imperfect explanations of the art, which have been transmitted to modern times. The reader may consult Cicero de Orat. lib. ii. cap. 87, 88.; Rhetor. ad Herennium, lib. iii. cap. 16, et seq.; Quinct. Inst. Orat. lib. xi. cap. 2.