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x                            Thet+R*^ ffACEz\.
VIs, or  fliacia, or Potenlia, &c. or 'tis i4, or msXt, &c. If none
of thefe will do, it remains to try, we
ther he may not have it, without any Name to it; and fay, 'tis " That
whereby one thing, coming in
" contact with another, moves, or fhakes, or breaks it," &c.--If
by any of thefe means he learns what Force
is, he does not form any new Idea: he only learns a new Name; and finds that
what he calls by one Name,
others call by another; or that what he had never taken the Pains to diflinguifh
by any Name, Some others
have.  To get the Idea, he muff have recourfe to Senfation, not to Language;
it being a pyfical Em,
and only to be attained that way.
BUT the fimple Idea called Force, being given; and coming to be afterwards
modified or circumitantiated
by new Accidents added thereto, and thus form'd into Terms, in this or that
Art, 'tis here in the Power of
Language, alone, to excite 'em; by refolving fuch compound Idea into its
ingredient ones, which being re-
compounded or put together again in the manner affign'd by the Definition,
gives the full adequate Import
thereof.---Thus the Idea of Force being varioufly modified, and combined
with other Ideas of Centre, Attragion,
Repulfion, Will, Machine, &c. in the Words, Central Force, Centripetal
Force, Centrifugal Force, Nece/lity or
Moral Force, Mechanick Power, &c. we can, by Definition, arrive at the
Meaning thereof; by having thofe
Circumifances fpecified, or fuperadded to the Idea of Force.----In this cafe,
there is no coming at the Idea by
Senfation; in regard 'tis a Creature of our own, and does not exift any where
without us, to make an Object
of Senfe.
H E N C E appears all the diverfity of Definitions; Technical ones, comporting
only to Terms, as to Central
Force , Scientifical or Philojophical, to Qualities, as Forciblenefs; and
2Vomin l or Succedaneous, belonging to
fimple Ideas, as Force.
'TIS the various Affemblage of fimple Ideas denoted by common Words, that
makes all the Variety of
Terms ; as 'tis of Simples in an Apothecary's Shop, that makes the Variety
of his Medicines.-The Analogy
goes farther ; and it may be faid that Terms, like Medicines, only differ
from  each other as their ingredient
Ideas, and the Relations thereof do differ.--If thefe be not all rehearsed
in the Definition, the Term or Me-
dicine is not fpecified, or dififinguifhed from fome other, which may have
all except that one or two omitted.
Confequently, fuch one or two are the Charaaerifticks of that Term; which
may be explain'd in fome fort,
by only enumerating thofe Chara~terifticks, and couching all the reff under
that other Term. This amounts to
little more than the Subftitution abovemention'd ; and yet to this is reducible
all that the Schoolmen teach of
Genus, Species, and Difference.
B ES ID E fimple Words, which we have obferved are, in their own Nature,
inexplicable; there are divers
others that become accidentally fo: And fuch are all the Data, or preliminary
Principles of any Art, with
refpe&t to thofe who confine themselves to the Bounds of that Art. Thus,
if it be demanded of an Apothe-
cary, to define one of his Simples, e. g. Mercury ; he muft needs be at a
fRand, unlefs he be likewife verfed
in Minerology,; by reafon it is putting him to explain a Datum, which his
Art does not explain, but affume;
the Explication thereof lying in another Province. For the Data or Principles
of any Art, are only explicable
from another, e. g. thofe of Chymizfry, Pharmacy, &c. from Phyficks;
Phyficks, from Phyjiology and Mechanicks;
Mechanicks from Geometry, &c. So that to explain Mercury, would to him
be, in fome meafiure, to explain
a fimple Idea. But afik him to define Calomel, and he is prepared for you;
and will readily enumerate the
feveral Ingredients, and the manner of preparing it: which is the proper
pharmaceutical Definition of Calomel.
H E RE it may be obferved, that the Words ufed in the Definition of a Term,
do many of 'em repre-
fent complex Ideas; and confequently ought themfelves to be defin'd, if we
would have the Definition com-
pleat. The Term has ufually divers fubaltern ones ; all which are refolvable
into it, and make part and parcel
of the Knowledge held forth by it. Thus, if Calomel be defined, " A
medicinal Pouder precipitated from
a Solution of crude Mercury in Aqua fortis, by adding thereto a Lixivium
of Sea Salt; and then purified
by repeated Ablutions in a Filtre," &c. The Ideas, Pouder, Precipitated,
Solution, Mercury, Aqua fortis, -
blution, Filtre, &c. remain to be explain'd, to furnifli the compleat
Notion of Calomel.--But as this would be
endlefs, and would defeat the Intention of a Definition; the Prachice obtains,
to fuppofe all other Terms
known, except that particular one under Definition. By this means, we avoid
the Embarrafs of bringing down
every Word to its Principles, or fimple Ideas; and acquit our felves by bringing
it to the next complex ones:
Since the bringing an unknown Term to feveral known ones, is a kind of indirect
Definition.
SU CH    is the Nature of a Technical Definition, which holds good or valid
for thofe of that Art, or
Craft ; who are to be fuppofed furnished with the neceflary Data, or preliminary
Notices.  But to make a
fcientifical Definition, we muff go fill lower; and bring down the Words,
if not to their fimple Ideas, yet
to general or common ones. For it is to be obferved, there are great numbers
of complex Ideas current
among moft People, which therefore may be confider'd as Data, and ufed as
fimple ones, for more conveniency
fake. All technical Apparatus, then, is to be here thrown by; and inftead
of giving five or fix hard Words
for one, the general Effe&t, and Meanings thereof are to be made ufe
of. Thus, Calomel may be defined " a
" white Pouder, which falls down from QZickfilver diffolved in Spirit
of Salt-petre, upon caffing Salt therein ;
and is afterwards waffled, again and again, by paffing fair Water thro' it,"
&c. Where, tho feveral of the
Words be complex; yet moft People, in the ordinary Courfe of Life, have framed
the complex Ideas be-
longing to 'em : fo that they may be confider'd as fimple ones.---Yet the
Definition can fcarce be faid to be
complete, even here: The general or philofophical Senfe of Words, we have
obferved, is form'd from the
grammatical one ; and consequently the Definition ought in ftriftnefs to
extend thither: The Solution, to be
adequate, fhould go as far as the Knot; the Analyfis as the Synthefis.
T H E Reader already begins to feel this Preface grow tirefoom; and yet half
the Bufinefs is fill behind.
When fo large a Work was to follow, he perhaps imagines he Ihould have been
excufed from a long Pre-
face: and the like, probably, may the Author fay; who, after fo tedious a
Work, cou'd not be over-fond of any
Supernumerary Fatigue. But, the Expediency of the Cafe, which fway'd and
determined the one; may fuffice
to fatisfy the other. Several Matters were purpofely waved in the 1Fourfe
of the Bo o K, to be treated of in
the P R E F A C E ; which appear'd the propereft Place for fuch Things as
have a regard to the whole Work.
What has been hitherto infifted on, as well as what remains, immediately
affeds every Article in the Book,
and tends, withal, to let a little needful Light into certain Points hitherto
involved in great Obfcurity.  I
confider a Preface, as a kind of Vehicle, wherewithal to convey the Reader
commodioufly from the Title into
the Book. The Preface is a kind of Comment on the Title, the Book a Paraphrafe
on it: Or, if you had
rather, the Book is the Title executed, the Preface the Title explained.
HAVING , therefore, difpatched the leading Words A R T, S C I E N C E, T
E R M, and D E F I N I T I O N;
we proceed to confider the Nature of a D IC 7I10 NAR  -- It were to be wifhed
that the many Adven-
turers in Print, who publifh their Thoughts under this or that Form and Denomination,
would frame them-
felves a precife Notion of the Character and Laws thereof. There is Something
arbitrary, and artificial in all
Wrtings: They are a kind of Draughts or Pictures, where the Afpect, Attitude,
and Light, which the Ob-
jects are taken in, tho merely arbitrary, yet fway and direct the whole Reprefentation.
Books are, as it were,
Plans