ties to that abstract complex idea, to which that name is annexed. But this diftinction of effences belonging particularly to fubftances, we fhall, when we come to confider their names, have an occafion to treat of more fully.

Effences ingenerable and incorruptible.

§. 19. That fuch abftract ideas, with names to them, as we have been speaking of, are effences, may farther appear by what we are told concerning effences, viz. that they are all ingenerable and incorruptible. Which cannot be true of the real conftitutions of things which begin and perish with them. All things that exift, befides their author, are all liable to change; especially those things we are acquainted with, and have ranked into bands under diftinct names or enfigns. Thus that which was grafs to-day, is to-morrow the flesh of a fheep; and within a few days after becomes part of a man: in all which, and the like changes, it is evident their real effence, i. e. that conftitution, whereon the properties of these feveral things depended, is destroyed and perifhes with them. But effences being taken for ideas, established in the mind, with names annexed to them, they are fuppofed to remain fteadily the fame, whatever mutations the particular fubftances are liable

For whatever becomes of Alexander and Bucephalus, the ideas to which man and horse are annexed, are fuppofed neverthelefs to remain the fame; and fo the effences of thofe fpecies are preferved whole and undeftroyed, whatever changes happen to any, or all of the individuals of thofe fpecies. By this means the effence of a fpecies refts fafe and entire, without the exiftence of fo much as one individual of that kind. For were there now no circle exifting any where in the world, (as perhaps that figure exifts not any where exactly marked out) yet the idea annexed to that name would not ceafe to be what it is; nor ccafe to be as a pattern to determine which of the particular figures we meet with have or have not a right to the name circle, and fo to fhow which of them by having that effence, was of that fpecies. And though there neither were nor had been in nature fuch a beaft as an unicorn, or

fuch

fuch a fish as a mermaid; yet fuppofing thofe names to ftand for complex abftract ideas that contained no inconfiftency in them, the effence of a mermaid is as intelligible as that of a man; and the idea of an unicorn as certain, fteady, and permanent as that of a horfe. From what has been faid it is evident, that the doctrine of the immutability of effences proves them to be only abstract ideas; and is founded on the relation eftablifhed between them and certain founds as figns of them and will always be true as long as the fame name can have the fame fignification.

§. 20. To conclude, this is that which in Recapitulafhort I would fay, viz. that all the great tion. bufinefs of genera and fpecies, and their effences, amounts to no more but this, That men making abstract ideas, and fettling them in their minds with names annexed to them, do thereby enable themselves to confider things, and difcourfe of them as it were in bundles, for the eafier and readier improvement and communication of their knowledge; which would adyance but flowly, were their words and thoughts confined only to particulars.

§. I.

TH

CHAP. IV.

Of the Names of Simple Ideas.

Names of fimple ideas, fubftances, have each fomething peculiar.

modes, and

HOUGH all words, as I have fhown, fignify nothing immediately but the ideas in the mind of the fpeaker; yet upon a nearer furvey we fhall find that the names of fimple ideas, mixed modes, (under which I comprife relations too) and natural fubftances, have each of them fomething peculiar and different from the other. ample:

For ex

1. Names of

§. 2. First, The names of fimple ideas and fubftances, with the abstract ideas in fimple ideas the mind, which they immediately fignify,

Gg3

and fub

intimate

ftances intimate real existence.

intimate alfo fome real exiftence, from which was derived their original pattern. But the names of mixed modes terminate in the idea that is in the mind, and lead not the thoughts any farther, as we fhall fee more at large in the following chapter.

2. Names of fimple ideas and modes fignify always both real and nominal effence.

§. 3. Secondly, The names of fimple ideas and modes fignify always the real as well as nominal effence of their fpecies. But the names of natural fubftances fignify rarely, if ever, any thing but barely the nominal effences of thofe fpecies; as we shall show in the chapter that treats of the names of fubftances in particular.

3. Names of fimple ideas undefinable.

§. 4. Thirdly, The names of fimple ideas are not capable of any definition; the names of all complex ideas are. It has

not, that I know, been yet obferved by any body, what words are, and what are not capable of being defined; the want whereof is (as I am apt to think) not feldom the occafion of great wrangling and obfcurity in men's difcourfes, whilft fome demand definitions of terms that cannot be defined; and others think they ought not to reft satisfied in an explication made by a more general word, and its restriction, (or, to speak in terms of art, by a genus and difference) when even after fuch definition made according to rule, those who hear it have often no more a clear conception of the meaning of the word than they had before. This at least I think, that the fhowing what words are, and what are not capable of definitions, and wherein confifts a good definition, is not wholly befides our prefent purpose; and perhaps will afford fo much light to the nature of thefe figns, and our ideas, as to deferve a more particular confideration.

If all were definable, it would be a

§. 5. I will not here trouble myself to prove that all terms are not definable from that progrefs in infinitum, which it will vifibly lead us into, if we fhould allow that all names could be defined. For if the terms of one definition were ftill to be defined by

procefs in in

finitum.

another,

another, where at laft fhould we ftop? But I fhall from the nature of our ideas, and the fignification of our words, fhow, why fome names can, and others cannot be defined, and which they are.

What a defi

nition is.

§. 6. I think, it is agreed, that a definition is nothing elfe but the fhowing the meaning of one word by feveral other not fynonimous terms. The meaning of words being only the ideas they are made to ftand for by him that ufes them, the meaning of any term is then fhowed, or the word is defined, when by other words the idea it is made the fign of, and annexed to, in the mind of the fpeaker, is as it were reprefented, or fet before the view of another; and thus its fignification afcertained: this is the only ufe and end of definitions; and therefore the only measure of what is, or is not a good defi

nition.

Simple ideas why unde

finable.

§. 7. This being premifed, I fay, that the names of fimple ideas, and those only are incapable of being defined. The reafon whereof is this, that the feveral terms of a definition, fignifying feveral ideas, they can all together by no means reprefent an idea, which has no compofition at all: and therefore definition, which is properly nothing but the fhowing the meaning of one word by feveral others not fignifying each the fame thing, can in the names of fimple ideas have no place.

§. 8. The not obferving this difference Inftances; in our ideas, and their names, has pro- motion. duced that eminent trifling in the fchools,

which is fo eafy to be obferved in the definitions they give us of fome few of thefe fimple ideas. For as to the greatest part of them, even thofe mafters of definitions were fain to leave them untouched, merely by the impoffibility they found in it. What more exquifite jargon could the wit of man invent, than this definition, "The act of a being in power, as far forth as in "power?" which would puzzle any rational man, to whom it was not already known by its famous abfurdity, to guess what word it could ever be fuppofed to be the explication of. If Tully, afking a Dutchman

Gg 4

what

what" beweeginge" was, fhould have received this explication in his own language, that it was "actus "entis in potentia quatenus in potentia;" I afk whether any one can imagine he could thereby have understood what the word "beweeginge" fignified, or have gueffed what idea a Dutchman ordinarily had in his mind, and would fignify to another, when he used that found.

§. 9. Nor have the modern philofophers, who have endeavoured to throw off the jargon of the schools, and fpeak intelligibly, much better fucceeded in defining fimple ideas, whether by explaining their causes, or any otherwife. The atomifts, who define motion to be a paffage from one place to another, what do they more than put one fynonymous word for another? For what is paffage other than motion? And if they were asked what paffage was, how would they better define it than by motion? For is it not at least as proper and fignificant to fay, paffage is a motion from one place to another, as to fay, motion is a paffage, &c.? This is to tranflate, and not to define, when we change two words of the fame fignification one for another; which, when one is better understood than the other, may serve to discover what idea the unknown ftands for; but is very far from a definition, unless we will fay every English word in the dictionary is the definition of the Latin word it anfwers, and that motion is a definition of motus. Nor will the fucceffive application of the parts of the fuperficies of one body to those of another, which the Cartefians give us, prove a much better definition of motion, when well examined.

Light.

§. 10. The act of perfpicuous, as far forth as perfpicuous," is another peripatetic definition of a fimple idea; which though not more abfurd than the former of motion, yet betrays its ufeleffness and infignificancy more plainly, becaufe experience will eafily convince any one, that it cannot make the meaning of the word light (which it pretends to define) at all understood by a blind man; but the definition of motion appears not at first fight fo useless, because it escapes this way of trial. For this fimple idea, entering by the touch as well as fight, it is im

poffible