fuch mafters, as the great-Huygenius, and the incompa rable Mr. Newton, with fome other of that ftrain, it is ambition enough to be employed as an under-labourer in clearing ground a little, and removing fome of the rubbish that lies in the way to knowledge; which certainly had been very much more,advanced in the world, if the endeavours of ingenious and industrious men had not been much cumbered with the learned, but frivolous ufe of uncouth, affected, or unintelligible terms, introduced into the sciences, and there made an art of, to that degree, that philofophy, which is nothing but the true knowledge of things, was thought unfit, or uncapable to be brought into well bred company, and poJite converfation. Vague and infignificant forms of fpeech, and abuse of language, have fo long paffed for mysteries of science; and hard or mifapplied words, with little or no meaning, have by prescription, such a right to be mistaken for deep learning, and height of fpeculation, that it will not be eafy to perfuade, either those who fpeak, or those who hear them, that they are but the covers of ignorance, and hinderance of true knowledge. To break in upon the fanctuary of vanity and ignorance, will be, I fuppofe, fome service to human understanding though fo few are apt to think, they deceive or are deceived in the ufe of words; or that the language of the fect they are of, has any faults in it, which ought to be examined or corrected; that I hope I fhall be pardoned, if I have in the third book dwelt long on this fubject; and endeavoured to make it fo plain, that neither the inveteratenefs of the mifchief, nor the prevalency of the fashion, fhall be any excufe for those who will not take care about the meaning of their own words, and will not fuffer the fignificancy of their expreffions to be inquired into.

I have been told, that a fhort epitome of this treatife, which was printed 1688, was by fome condemned without reading, because innate ideas were denied in it; they too hastily concluding, that if innate ideas were not fuppofed, there would be little left, either of the notion or proof of fpirits. If any one take the like offence at the entrance of this treatife, I fhall defire him to read it

thorough; and then I hope he will be convinced, that the taking away falfe foundations, is not to the prejudice, but advantage of truth; which is never injured or endangered fo much, as when mixed with, or built on falfehood. In the fecond edition, I added as followeth :

The bookfeller will not forgive me, if I fay nothing of this fecond edition, which he has promifed, by the correctness of it, fhall make amends for the many faults committed in the former. He defires too, that it fhould be known, that it has one whole new chapter concerning identity, and many additions and amendments in other places. Thefe, I must inform my reader, are not all new matter, but most of them either farther confirmation of what I had faid, or explications, to prevent others being mistaken in the fenfe of what was formerly printed, and not any variation in me from it: I muft only except the alterations I have made in Book II. Chap. 21.

What I had there writ concerning liberty and the will, I thought deferved as accurate a view as I was capable of; thofe fubjects having, in all ages, exercifed the learned part of the world with questions and difficulties, that have not a little perplexed morality and divinity; thofe parts of knowledge that men are most concerned to be clear in. Upon a closer inspection into the working of mens minds, and a stricter examination of those motives and views they are turned by, I have found reafon fomewhat to alter the thoughts I formerly had concerning that, which gives the laft determination to the will in all voluntary actions. This I cannot forbear to acknowledge to the world, with as much freedom and readiness, as I at firft published what then feemed to me to be right, thinking myself more concerned to quit and renounce any opinion, than oppofe that of another, when truth appears against it: For it is truth alone Í feek, and that will always be welcome to me, when, or from whencefoever it comes.

But what forwardnefs foever I have to refign any opinion I have, or to recede from any thing I have writ, upon the first evidence of an error in it; yet this I must own, that I have not had the good luck to receive any

light from thofe exceptions I have met with in print ágainft any part of my book; nor have, from any thing has been urged against it, found reafon to alter my fenfe, in any of the points have been questioned. Whe ther the fubject I have in hand requires often more thought and attention, than curfory readers, at least fuch as are prepoffeffed, are willing to allow; or whether any obfcurity in my expreffions cafts a cloud over it, and thefe notions are made difficult to others appréhenfion in my way of treating them; fo it is, that my meaning, I find, is often mistaken, and I have notothe good luck to be every where rightly understood. There are fo many inftances of this, that I think it justice to my reader and myfelf, to conclude, that either my book is plainly enough written to be rightly understood by thefe, who perufe it with that attention and indifferency, which every one, who will give himself the pains to read, ought to employ in reading; or elfe that I have writ mine fo obfcurely, that it is in vain to go about to mend it. Which ever of these be that truth, it is myfelf only am affected thereby, and therefore I fhall be far from troubling my reader with what I think might be faid, in anfwer to thofe feveral objections I have met with, to paffages here and there of my book. Since I perfuade myself, that he who thinks them of moment enough to be concerned, whether they are true or false, will be able to fee, that what is faid, is either not well founded, or elfe not contrary to my doctrine, when I and my oppofer come both to be well understood. us

If any, careful that none of their good thoughts fhould be loft, have published their cenfures of my Effy, with this honour done to it, that they will not futter it to be an Effay; I leave it to the public to value the obligation they have to their critical pens, and fhall not wafte my reader's time in fo idle or ill-natured antemployment of mine, as to leffen the fatisfaction any one has in himself, or gives to others in fo hafty a confutation of what I have written.

The bookfeller's preparing for the fourth edition of my Effay, gave me notice of it, that I might, if I had leifure, make any additions or alterations i fhould think

fit. Whereupon I thought it convenient to advertise the reader, that befides feveral corrections I had male bere and there, there was one alteration which it was neceffary to mention, because it ran through the whole book, and is of confequence to be rightly understood. What thereupon faid, was this.

*ts Clear and diflinct ideas are terms, which though famihar and frequent in mens, mouths, I have reafon to think every one who uses, does not perfectly underftand; and poffibly it is but here and there one, who gives himself the trouble to confider them so far as to know what he himself or others precifely mean by them: I have therefore in most places chose to put determinate or determined, instead of clear and diftinct, as more likely to direct mens thoughts to my meaning in this matter. By thofe denominations, I mean fome object in the mind, and confequently determined, i. e. fuch as it is there feen and perceived to be. This, I think, may fitly be called a determinate or determined idea, when fuch as it is at any time objectively in the mind, and fo determined there, it is annexed, and without variation determined to a name or articulate found, which is to be fteadily the fign of that very fame object of the mind, or deterininate idea.

! To explain this a little more particularly. By determinate, when applied to a fimple idea, I mean that fimple appearance which the mind has in its view, or perceives in itself, when that idea is faid to be in it; by determined, when applied to a complex idea, I mean fuch an one as confifts of a determinate number of certain fimple or lefs complex ideas, joined in fuch a proportion and fituation, as the mind has before its view, and fees in itself when that idea is prefent in it, or fhould be present -in it, when a man gives a name to it. I fay should be; because it is not every one, nor perhaps any one, who -is fo careful of his language, as to ufe no word, till he views in his mind the precife determined idea, which he -resolves to make it the fign of. The want of this, is the cause of no fmall obfcurity, and confufion in mens y thoughts and difcourfes.

I know there are not words enough in any language, to answer all the variety of ideas, that enter into mens difcourfes and reafonings. But this hinders not, but that when any one ufes any term, he may have in his mind a determined idea, which he makes it the fign of, and to which he should keep it steadily annexed, during that prefent difcourfe. Where he does not, or cannot do this, he in vain pretends to clear or diftinct ideas: It is plain his are not fo; and therefore there can be expected nothing but obfcurity and confufion, where fuch terms are made ufe of, which have not fuch a precise determination.

Upon this ground I have thought determined ideas a way of fpeaking lefs liable to mistake, than clear and dif tinct; and where men have got fuch determined ideas of all that they reafon, inquire, or argue about, they will find a great part of their doubts and disputes at an end, The greatest part of the questions and controverfies that perplex mankind, depending on the doubtful and uncertain ufe of words, or (which is the fame), indetermină ed ideas, which they are made to ftand for; I have made choice of thefe terms to fignify, 1. Some immediate ob ject of the mind, which it perceives and has before it, diftinct from the found it uses as a fign of it. 2. That this idea, thus determined, i. e. which the mind has in itfelf, and knows and fees there, be determined without any change to that name, and that name determined to that precife idea. If men had fuch determined ideas in their inquiries and difcourfes, they would both difcern how far their own inquiries and difcourfes went, and avoid the greatest part of the difputes and wranglings they have with others.

Befides this, the bookfeller will think it necessary I fhould advertise the reader, that there is an addition of two chapters wholly new; the one of the Affociation of Ideas, the other of Enthufiafm. Thefe, with fome other larger additions never before printed, he has engaged to print by themselves after the fame manner, and for the fame purpose, as was done when this Effay had the fecond impreffion.