confider, upon a fuperficial view, as ultimate facts are refolvable into other principles ftill more general. Long before we are capable of reflection," (fays Dr. Reid,)" the original perceptions and notions of the "mind are fo mixed, compounded, and decompound

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ed, by habits, affociations, and abftractions, that it "is extremely difficult for the mind to return upon "its own footsteps, and trace back those operations " which have employed it since it first began to think "and to act." The fame author remarks, that,

we could obtain a distinct and full history of all that "hath paffed in the mind of a child, from the begin"ning of life and fenfation, till it grows up to the use "of reafon; how its infant faculties began to work, and "how they brought forth and ripened all the various "notions, opinions, and fentiments, which we find in "ourselves when we come to be capable of reflection;

this would be a treasure of Natural History, which "would probably give more light into the human faculties, than all the fyftems of philofophers about them, fince the beginning of the world." To accomplish an analysis of these complicated phenomena into the fimple and original principles of our conftitution, is the great object of this branch of philosophy; but, in order to fucceed, it is neceffary to afcertain facts before we begin to reafon, and to avoid generalizing, in any instance, till we have completely fecured the ground that we have gained. Such a caution, which is neceffary in all the sciences, is, in a more peculiar manner, neceffary here, where the very facts from which all our inferences must be drawn, are to be af certained only by the most patient attention; and,

where almost all of them are, to a great degree, difguifed; partly by the inaccuracies of popular language, and partly by the mistaken theories of philofophers.

I have only to add, that, although I have retained the phrafe of the Affociation of Ideas, in compliance with common language, I am far from being completely fatisfied with this mode of expreffion. I have retained it, chiefly that I might not expofe myself to the cenfure of delivering old doctrines in a new form.

As I have endeavoured to employ it with caution, I hope that it has not often mifled me in my reasonings. At the fame time, I am more and more convinced of the advantages to be derived from a reformation of the common language, in most of the branches of science. How much fuch a reformation has effected in Chemistry is well known; and it is evidently much more neceffary in the Philofophy of Mind, where the prevailing language adds to the common inaccuracies of popu lar expreflions, the peculiar difadvantage of being all fuggested by the analogy of matter. Often, in the compofition of this work, have I recollected the advice of Bergman to Morveau *. "In reforming the "nomenclature of chemistry, fpare no word which is improper. They who understand the fubject already, will fuffer no inconvenience; and they

*"Le favant Profeffeur d'Upfal, M. Bergman, écrivoît à M. "de Morveau dans les derniers temps de fa vie, ne faites graces "à aucune denomination impropre. Ceux qui favent déja enten"dront toujours; ceux qui ne favent pas encore entendront "plutôt." Methode de Nomenclat. Chemique, par MM. MORVEAU, LAVOISIER, &c.

to whom the fubject is new, will comprehend "it with the greater facility." But it belongs to fuch authors alone, as have extended the boundaries' of science by their own discoveries, to introduce inno. vations in language with any hopes of fuccefs.

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General Obfervations on Memory.

AMONG the various powers of the understanding,

there is none which has been fo attentively exa

mined by philofophers, or concerning which fo many important facts and obfervations have been collected, as the faculty of Memory. This is partly to be afcribed to its nature, which renders it easily distinguishable from all the other principles of our conftitution, even by those who have not been accustomed to metaphy. fical investigations; and partly to its immediate fubferviency, not only to the pursuits of science, but to the ordinary business of life; in confequence of which, many of its most curious laws had been obferved, long before any analysis was attempted of the other powers of the mind; and have, for many ages, formed a part of the common maxims which are to be found in every treatise of education. Some important remarks on the fubject may, in particular, be collected from the wri tings of the antient rhetoricians.

The word Memory is not employed uniformly in the fame precise fenfe; but it always expreffes fome modification of that faculty, which enables us to treasure up, and preferve for future use, the knowledge we ac

quire; a faculty which is obviously the great foundation of all intellectual improvement, and without which, no advantage could be derived from the moft enlarged experience. This faculty implies two things: a capacity of retaining knowledge; and a power of recalling it to our thoughts when we have occafion to apply it to use. The word Memory is fometimes employed to express the capacity, and fometimes the power. When we speak of a retentive memory, we use it in the for mer sense; when, of a ready memory, in the latter.

The various particulars which compose our stock of knowledge are, from time to time, recalled to our thoughts, in one of two ways: fometimes they recur to us fpontaneoufly, or at leaft, without any interference on our part; in other cafes, they are recalled, in confe quence of an effort of our will. For the former operation of the mind, we have no appropriated name in our language, diflinct from Memory. The latter, too, is often called by the fame name, but is more properly diftinguished by the word Recollection.

There are, I believe, fome other acceptations befides these, in which the word Memory has been occafionally employed; but as its ambiguities are not of such a nature as to mislead us in our prefent inquiries, I fhall not dwell any longer on the illuftration of diftinctions, which to the greater part of readers might appear uninteresting and minute. One diftinction only, relative to this fubject, occurs to me, as deferving particular attention.

The operations of Memory relate either to things and their relations, or to events. In the former case, thoughts which have been previously in the mind, may

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recur