ceffarily acquire additional ftrength from our favorite ftudy.

2. In proportion as a fcience becomes more far miliar to us, we acquire a greater command of attention with refpect to the objects about which it is converfant; for the information which we already poffefs, gives us an intereft in every new truth, and every new fact which have any relation to it. In moft cafes, our habits of inattention may be traced to a want of curiofity; and therefore fuch habits are to be corrected, not by endeavoring to force the attention in particular inftances, but by gradually learning to place the ideas which we wish to remember, in an interesting point of view.

3. When we first enter on any new literary purfuit, we are unable to make a proper difcrimination in point of utility and importance, among the ideas which are prefented to us; and by attempting to grafp at every thing, we fail in making thofe moderate acquifitions which are fuited to the limited powers of the human mind. As our information extends, our selection becomes more judicious and more confined; and our knowledge of useful and connected truths advances rapidly, from our ceafing to diftract the attention with fuch as are detached and infignificant

4. Every object of our knowledge is related to a variety of others; and may be prefented to the thoughts, fometimes by one principle of affociation, and fometimes by another. In proportion, therefore, to the multiplication of mutual relations among our ideas, (which is the natural result of growing information, and in particular, of habits of phylofophical ftudy,) the greater will be the number of occafionson which they will recur to the recollection, and the firmer will be the root which each idea, in particular, will take in the memory.

It follows, too, from this obfervation, that the fa

cility of retaining a new fact, or a new idea, will depend on the number of relations which it bears to the former objects of our knowledge; and, on the other hand, that every fuch acquifition, fo far from loading the memory, gives us a firmer hold of all that part of our previous imformation, with which it is in any degree connected.

It may not, perhaps, be improper to take this opportunity of obferving, although the remark be not immediately connected with our present fubject, that the acceffion made to the stock of our knowledge, by the new facts and ideas which we acquire, is not to be estimated merely by the number of these facts and ideas confidered individually; but by the number of relations which they bear to one another, and to all the different particulars which were previously in the mind; for, "new knowledge," (as Mr. Maclaurin has well remarked,*) "does not confift fo much in "in our having access to a new object, as in com"paring it with others already known, obferving its "relations to them, or difcerning what it has in "common with them, and wherein their disparity "confifts: and, therefore, our knowledge is vaftly

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greater than the fum of what all its objects fepa"rately could afford; and when a new object comes "within our reach, the addition to our knowledge "is the greater, the more we already know; fo that "it increases, not as the new objects increase, but in "a much higher proportion."

5. In the laft place, the natural powers of Memory are, in the cafe of the philofopher, greatly aided by his peculiar habits of claffification and arrangement. As this is by far the most important improvement of which Memory is fufceptible, I fhall confider it more particular than any of the others I have mentioned.

* See the Conclusion of his View of NEWTON's Discoveries.

The advantages which the memory derives from. a proper claffification of our ideas, may be beft conceived by attending to its effects, in enabling us to conduct, with ease, the common business of life. In what inextrible confufion would the lawyer or the merchant be immediately involved, if he were to depofit, in his cabinet, promifcuously, the various written documents which daily and hourly pafs through his hands? Nor could this confufion be prevented by the natural powers of memory, however vigorous they might happen to be, By a proper diftribution of thefe documents, and a judicious referrence of them to a few general titles, a very ordinary memory is enabled to accomplish more, than the most retentive, unaffifted by method. We know, with certainty, where to find any article we may have occafion for, if it be in our poffeffion; and the search is confined within reafonable limits, inftead of being allowed to wander at random amidst a chaos of par'ticulars.

Or, to take an instance still more immediately applicable to our purpose: fuppofe that a man of letters were to record, in a common-place, book, without any method, all the various ideas and facts which occurred to him in the courfe of his ftudies; what difficulties would he perpetually experience in applying his acquifitions to use? and how completely and eafily might thefe difficulties be obviated by refering the particulars of his information to certain general heads? It is obvious, too, that, by doing fo, he would not only have his knowledge much more completely under his command, but as the particulars claffed together would all have fome connection more or less, with each other, he would be enabled to trace with advantage, thofe mutual relations among his ideas, which it is the object of philofophy to ascertain.

A common-place book, conducted without any

method, is an exact picture of the memory of a man whose inquiries are not directed by philosophy. And the advantages of order in treasuring up our ideas in the mind, are perfectly analogous to its effects when they are recorded in writing.

Nor is this all. In order to retain our knowledge diftinctly and permanently, it is neceffary that we fhould frequently recal it to our recollection. But how can this be done without the aid of arrangement? Or fuppofing that it were poffible, how much time and labor would be neceffary for bringing under our view the various particulars of which our information is compofed? In proportion as it is properly fyftematised, this time and labor are abridged. The mind dwells habitually, not on detached facts, but on a comparatively fmall number of general principles; and, by means of these, it can fummon up, as occafions may require, an infinite number of particulars affociated with them; each of which, confidered as a folitary truth, would have been as burthenfome to the memory, as the general principle with which it is connected.

I would not wifh it to be understood from these obfervations, that philofophy confifts in claffification alone; and that its only ufe is to affift the memory. I have often, indeed, heard this afferted in general terms; but it appears to me to be obvious, that although this be one of its most important ufes, yet fomething more is neceffary to complete the definition of it. Were the cafe otherwife, it would follow, that all claffifications are equally philofophical provided they are equally comprehenfive. The very great importance of this fubject will, I hope, be a fufficient apology for me, in taking this opportunity to correct fome mistaken opinions which have been formed concerning it.

Continuation of the fame fubject.-Aid which the Memo. ry derives from Philofophical Arrangement.

IT was before obferved, that the great ufe of the faculty of Memory, is to enable us to treasure up, for the future regulation of our conduct, the results of our past experience, and of our paft reflections. But in every cafe in which we judge of the future from the past, we must proceed on the belief, that there is, in the courfe of events, a certain degree, at leaft, of uniformity. And, accordingly, this belief is not only juftified by experience, but (as Dr. Reid has fhewn, in a very fatisfactory manner) it forms a part of the original conftitution of the human mind. In the general laws of the material world, this uniformity is found to be complete; infomuch that, in the fame combinations of circumftances, we expect, with the most perfect affurance, that the fame results will take place. In the moral world, the course of events does not appear to be equally regular; but ftill it is regular, to fo great a degree, as to afford us many rules of importance in the conduct of life.

A knowledge of Nature, in fo far as it is abfolutely neceffary for the prefervation of our animal exiftence, is obtruded on us, without any reflection on our part, from our earliest infancy. It is thus that children learn of themselves to accommodate their conduct to the established laws of the material world. In doing fo, they are guided merely by memory, and the inftinctive principle of anticipation, which has just been mentioned.

In forming conclufions concerning future events, the philofopher, as well as the infant, can only build with fafety on past experience; and he, too, as well as the infant, proceeds on an instinctive belief, for