by the Definition of the Name. Thus the Philosophers believe that there is nothing in the World more unquestionable than that Fire is hot, or that a Stone is heavy, and that it would be a folly to deny either. Which indeed they may make all the world believe, so long as they forbear from the Definition of Names. But when once they do that, it will presently appear what is obscure, and what apparent in reference to those things. First then it is to be asked them, what they mean by the words Hot and Ponderous ? For if they answer that by Hot they only mean that which is proper to cause in us a Sentiment of Heat, and by Heavy that which falls downwards not being propped up; they may then rightly say, that it is a folly to deny Fire to be Hot and Stones to be Heavy. But if they mean by Heat that which has in itself a Quality like to that which we imagine when we feel heat; and by Heavy that which has in itself an Internal Principle which causes it to fall to the Centre, not being compelled by any violence from without; it will be easy then to demonstrate to them, that it is no denial of a clear thing, but of a thing which is very obscure, if not altogether false, that Fire is hot in that Sense, or that a Stone is heavy; in regard it is apparent that Fire causes in us a sense of Heat, by that action whereby it operates upon our Bodies, but it is no way evident that there is in the Fire any thing like to that which we feel in the Fire. And it is as evident in the same manner that Stones fall down; but it is not so clear, that they fall of themselves without any outward detruding Violence.

Thus we see the great benefit of defining names, for that by this means we understand what it is we dispute of, that we may not contend in vain about words, which we understand some one way, some another, as is frequently practised even in our ordinary discourses.

But besides this benefit there is also another, which is, that we cannot many times have a distinct Idea of a thing, unless we make use of many words to denote it. Now it would be Impertinent especially in writings that concern the Sciences to be always repeating a long Series of words. And therefore having once defined the thing by several words, we fix to some one word the Idea conceived to serve instead of all the rest.

Thus after we have found that there are numbers that may be divided into two equal Numbers, to avoid the often repetition of those words, we fix this Property, and call a number that may be divided into two equal Numbers, an even Number. Whence it is apparent, that as often as we make use of the defined Name, the Definition is to be mentally supplied, which a Man must have

always so ready in his Mind, that as soon as he hears even Numbers, he presently understands such a number as may be divided into two Numbers: and these two things ought to be so inseparable from the thoughts, that the Tongue should no sooner express the one, but the Mind should add the other. For they who have defined Names as the Geometricians do with so much Care, did it only to abridge their Writings (or as St. Austin says) Lest by continual Circumlocution they should Create delays: but yet they do not do it to abridge the Ideas of the things of which they discourse, believing the Mind will supply the entire Definition to short words, which they only make use of to avoid the Perplexity which a multitude of words would produce.

CHAP. XII.

Certain Observations of great Importance, touching the Definition of Words.

HAVING thus explained the nature, benefit and necessity of the definition of Names, it will not be from the purpose to speak something of their use, lest an ill use be made of them.

First, all Names are not to be defined; for that would be often unprofitable and impossible to be done. I say unprofitable; for when the Ideas conceived of things are distinct, and all Men understanding the same Language, conceive the same Idea, it would be superfluous to define such a name, because we have already the intent of the Definition, as being fixed without a definition to the distinct and clear Idea.

But this happens in things that are purely simple, of which all Men naturally have the same Idea, so that the words by which they are denoted, are understood by all men in the same sense, or if there be any mixture of obscurity, that which is clear is primarily understood. And so they who make use of such words to denote a clear Idea, need not fear lest they should be understood amiss. Such are the words, Ens, or being, Thought, Extension, Equality, Duration or Time. For though some may obscure the Idea of Time by several Propositions, which they call Definitions; as that Time is the measure of motion according to Priority and Posteriority; nevertheless they never mind these definitions themselves, when they speak of Time, nor do they conceive any other thing of it. So that both Learned and Unlearned with the same facility understand the same thing when they bear, that a Horse takes up less time in pacing a Furlong than a Tortoise,

I have said moreover, that it is impossible to define all words. In regard that to define some words, there is a necessity of using other words that express the Idea, to which that word is to be annexed. And then if these words which were made use of to explain the first, be also to be defined, there will be a necessity for other words, and so on endlessly. And therefore there are some primitive words which cannot be defined, and it would be as great a fault to be too curious about their Definitions, as not to define sufficiently; for both ways we fall into the same Confusion, which we labour to avoid.

The second observation is, that we ought not to change Definitions known and already received, unless we meet with something in them that is to be found fault with; for it is always more easy to teach the signification of a word to others, when Custom already received, at least among the Learned, has fixed it to an Idea, than to annex it anew to another Idea, and force it from a former, to which it has been properly joined by daily use. And therefore it would be a great error to alter the Definitions received by the Mathematicians, unless where there are any that are not sufficiently plain and obvious to Sense, or such whose Ideas are not Politely described as in Euclid may be thought the Definition of Angle and Proportion.

Thirdly it is to be observed that when there is a necessity to define a name, it behoves us to approach as near as may be to common Custom, and not to give to words a Sense altogether. foreign to what they already have, or which are contrary to their Etymology; as if a Parallellogram should be defined, a figure consisting of three Lines. But if the word has two significations, it must be deprived of one, that the other may be only affixed to it. Thus when Heat signifies as well the feeling which we have of it, as the Quality which we believe to be in the Fire, like to that which we feel, to remove this ambiguity, I will use the name of Heat, but I must not apply it but to one of these Ideas, dismissing it from the other, saying, I call Heat that feeling which I have when I approach near the Fire; and to the cause of this Sensation I would give a name altogether different, as of Ardour or Burning; or else the same name with some addition, which determines and distinguishes it from heat taken for the Sensation of it, as is that of Virtual Heat.

The reason of this observation is taken from hence, that Men after they have once affixed an Idea to a word, are not easily in duced to separate it from the word: and so the old Idea still returning, obliterates the new which they have from the late Defi

nition. So that Men more easily accustom themselves to a word of no Signification, as if a Man should rather use the word Bara to signify a Figure consisting of three Lines, than despoil the word Parallellogram of the Idea of a Figure whose opposite sides are Parallel, to make it signify a Figure whose opposite sides are hot Parallel.

This is an Error into which all the Chymists are fallen, who take delight to change the names of most things of which they discourse, and to give them names which already signify quite other things, and which have no correspondence with the Ideas to which they join the words. Hence those ridiculous ratiocinations of some of those people, particularly of one who asserts, that the Pestilence, as he imagined, being a Saturnine Disease, was to be cured by hanging about the Neck of the Patient a plate of Lead, which is called Saturn by the Chymists, and whereon is also to be engraved upon a Saturday, which day is also sacred to Saturn, the Character by which the Astronomers denote that Planet. As if arbitrary [and feigned sympathetic Affinities between Lead and the Planet Saturn, or between the same Planet and Saturday or the little Signature of the Astronomers could be any way effectual for the Cure of Diseases.

But what is more insufferable in this jargon of the Chymists is their Prophaning the Sacred Mysteries of Religion to make them serve as a Veil to cover their pretended Secrets; insomuch that some are arrived at that height of Impiety, as to apply what the Scriptures speak of the true Christians, That they are the Chosen Race, the Royal Priesthood, the Holy Nation, the People purchased by God, and whom he has called out of Darkness to his wonderful Light, to the chimerical Fraternity of the Rosicrucians, whom in their own Imaginations they term the only wise men that have attained Immortal Happiness; as having by virtue of the Philosopher's Stone found out the way to fix the Soul in the Body; from this, as they say, that there is no Body so fixed and incorruptible as Gold. Of which dreams, and of several others of the same nature there are to be found a great number in Gassendus's Examen of Flud's Philosophy. Which demonstrates that there is no disease of the mind more dangerous than that of Enigmatical Scribbling, which causes men to imagine that their least solid thoughts, if I may not call them false and altogether Impious, will pass for great Mysteries, if clad in words unintelligible to the Common sort of men.

CHAP. XIII.

Of another sort of Definitions of Names by which their Significations are denoted according to Common Use.

ALL that has been said of the Definition of names ought to be understood only of those, by which every one defines the words for his particular use; and this is that which renders them free and Arbitrary, it being in the power of every one to make use of what Sound he pleases to express his Ideas, provided he previously give notice. But in regard that men are not perfect masters of any but their own language, every one has a privilege to make a Dictionary for his own Use, but not for others, nor to interpret their words by particular Significations which we have fixed to words of his own. And therefore seeing that notion of words is not to be explained which is proper to ourselves, but that which is proper to the word according to Common Use, such Definitions are not to be called Arbitrary, yet are they to be obliged to represent, though not the truth of the Thing, yet the truth of the Use; and they are to be esteemed false if they do not really express the Use, that is, if they do not join to Sounds the same Ideas which are annexed to such sounds by the Common Custom of those that make Use of them. And this demonstrates also to us that Definitions may be contested, because we find daily disputes about the signification which Custom gives to words.

Now, though these sorts of Definitions of words seem to be the business of the Grammarians, whose Province it is to make Dictionaries, which are nothing else but the Explication of Ideas which men have agreed to affix certain Sounds, yet may we raise upon this Subject several important Reflections for the rectifying our Judgments.

The first, which may serve as the foundation of all the rest, that men do not many times consider the whole signification of words; that is, that the words often signify more than they seem to signify, and that therefore they who interpret the signification, do not thoroughly unfold all the Ideas which the words imprint in the minds of the Hearers.

For to signify in a Sound pronounced or written is no other than to raise an Idea by striking our Ears or our Eyes. Now it comes frequently to pass, that one word, besides the principal Idea, which is looked upon as the proper signification of the word, excites several other Ideas, which may be termed Accessories, of which we take little notice, although the mind receive their Impression.