nevertheless to remain the same; and so the essences of those species are preserved whole and undestroyed, whatever changes happen to any or all of the individuals of those species. By this means the essence of a species rests safe and entire, without the existence of so much as one individual of that kind. For were there now no circle existing anywhere in the world (as perhaps that figure exists not anywhere exactly marked out), yet the idea annexed to that name would not cease to be what it is; nor cease 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 so to show which of them, by having that essence, was of that species. And though there neither were nor had been in nature such a beast as an unicorn, or such a fish as a mermaid; yet supposing those names to stand for complex abstract ideas that contained no inconsistency in them, the essence of a mermaid is as intelligible as that of a man; and the idea of an unicorn as certain, steady, and permanent as that of a horse. From what has been said it is evident, that' the doctrine of the immutability of essences proves them to be only abstract ideas; and is founded on the relation established between them and certain sounds as signs of them; and will always be true as long as the same name can have the same signification.

tion.

§ 20. To conclude, this is that which Recapitulain short I would say; viz. that all the great business of genera and species, and their essences, amounts to no more but this, That men making abstract ideas, and settling them in their minds with names annexed to them, do thereby enable themselves to consider things, and discourse of them as it were in bundles, for the easier and readier improvement and communication of their knowledge; which would advance but slowly were their words and thoughts confined only to particulars.

Names of

186

CHAPTER IV.

Of the Names of Simple Ideas.

§ 1. THOUGH all words, as I have simple ideas, shown, signify nothing immediately but modes, and the ideas in the mind of the speaker: yet substances, have each upon a nearer survey we shall find that something the names of simple ideas, mixed modes peculiar. (under which I comprise relations too), and natural substances, have each of them something peculiar and different from the other. For example; § 2. First, The names of simple ideas and substances, with the abstract ideas in the mind which they immediately signify, intimate also some real existence, 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 shall see more at large in the following chapter.

1. Names of simple ideas and substances intimate real existence.

2. Names of simple ideas and modes signify always both real and

§ 3. Secondly, The names of simple ideas and modes signify always the real as well as nominal essence of their species. But the names of natural substances signify rarely, if ever, any thing but barely the nominal essences of those species; as we shall show in the chapter that treats of the names of substances in particular.

nominal es

sence.

3. Names of § 4. Thirdly, The names of simple simple ideas ideas are not capable of any definition; undefinable. the names of all complex ideas are. It has not, that I know, been yet observed 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 seldom the occasion of great wrangling and obscurity in men's discourses, whilst some demand definitions of terms that cannot be defined; and others think they ought not to rest 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 such 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 showing what words are, and what are not, capable of definitions, and wherein consists a good definition, is not wholly besides our present purpose; and perhaps will afford so much light to the nature of these signs, and our ideas, as to deserve a more particular consideration.

If all were

definable, it would be a process in infinitum. defined by

§ 5. I will not here trouble myself to prove that all terms are not definable from that progress in infinitum, which it will visibly lead us into, if we should allow that all names could be defined. For if the terms of one definition were still to be another, where at last should we stop? But I shall, from the nature of our ideas, and the signification of our words, show why some names can, and others cannot, be defined, and which they are.

What a de

finition is.

§ 6. I think it is agreed, that a definition is nothing else but the showing the meaning of one word by several other not synonymous terms. The meaning of words being only the ideas they are made to stand for by him that uses them, the meaning of any term is then showed, or the word is defined, when by other words the idea it is made the sign of, and annexed to, in the mind of the speaker, is as it were represented or set before the view of another, and thus its signification ascertained; this is the only use and end of definitions; and therefore the only measure of what is or is not a good definition.

§ 7. This being premised, I say that the names of simple ideas, and those only, are incapable of being defined. The rea

Simple ideas why unde

finable.

son whereof is this: that the several terms of a de

Instances; motion.

finition, signifying several ideas, they can all together by no means represent an idea, which has no composition at all and therefore a definition, which is properly nothing but the showing the meaning of one word by several others not signifying each the same thing, can in the names of simple ideas have no place. § 8. The not observing this difference in our ideas, and their names, has produced that eminent trifling in the schools which is so easy to be observed in the definitions they give us of some few of these simple ideas. For as to the greatest part of them, even those masters of definitions were fain to leave them untouched, merely by the impossibility they found in it. What more exquisite 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 absurdity, to guess what word it could ever be supposed to be the explication of. If Tully, asking a Dutchman what "beweeginge" was, should have received this explication in his own language, that it was "actus entis in potentia quatenus in potentia;" I ask whether any one can imagine he could thereby have understood what the word "beweeginge" signified, or have guessed what idea a Dutchman ordinarily had in his mind, and would signify to another, when he used that sound.

any

§ 9. Nor have the modern philosophers, who have endeavoured to throw off the jargon of the schools, and speak intelligibly, much better succeeded in defining simple ideas, whether by explaining their causes, or otherwise. The atomists, who define motion to be a passage from one place to another, what do they more than put one synonymous word for another? For what is passage other than motion? And if they were asked what passage was, how would they better define it than by motion? For is it not at least as proper and significant to say, passage is a motion. from one place to another, as to say, motion is a pass

age, &c.? This is to translate, and not to define, when we change two words of the same signification one for another; which, when one is better understood than the other, may serve to discover what idea the unknown stands for; but is very far from a definition, unless we will say every English word in the dictionary is the definition of the Latin word it answers, and that motion is a definition of motus. Nor will the successive application of the parts of the superficies of one body to those of another, which the Cartesians give us, prove a much better definition of motion, when well examined.

Light.

§ 10. "The act of perspicuous, as far forth as perspicuous," is another peripatetic definition of a simple idea; which though not more absurd than the former of motion, yet betrays its uselessness and insignificancy more plainly, because experience will easily 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 sight so useless, because it escapes this way of trial. For this simple idea, entering by the touch as well as sight, it is impossible to show an example of any one, who has no other way to get the idea of motion but barely by the definition of that name. Those who tell us that light is a great number of little globules, striking briskly on the bottom of the eye, speak more intelligibly than the schools; but yet these words, ever so well understood, would make the idea the word. light stands for no more known to a man that understands it not before, than if one should tell him that light was nothing but a company of little tennis-balls, which fairies all day long struck with rackets against some men's foreheads, whilst they passed by others. For granting this explication of the thing to be true, yet the idea of the cause of light, if we had it ever so exact, would no more give us the idea of light itself, as it is such a particular perception in us, than the