13 
LOGIC. 
Jute value, trufting implicitly to tlieii* guidance. To 
over-rate the ancients in this way, is'to put hack the un- 
derftanding to the ftate of infancy, and to neglect the 
ufe of our own talents. Befides, we deceive ourfelves 
greatly if we believe that all the writings of the ancients 
were equally claflical with thofe which have defcended to 
us ; for time fifts every thing, and only retains that which 
has an intrinfic value. We may therefore juftly fuppole 
that we poiTefs only the belt writings of the ancients. 
There are various caufes by which the prejudice in fa¬ 
vour of antiquity is produced and maintained. When 
we difcover any thing in the Ancients, which, confider- 
ing the circumftances of the times they lived in, ex¬ 
ceeds our expectation, we are filled with furprife andad- 
miration. Befides a Knowledge of the Ancients is a 
proof of erudition and great reading, which are always 
efteemed, however trifling and unimportant the Know¬ 
ledge may be which is obtained from that ftudy. The 
obligation we are under to them for having introduced us 
to many fpecies of Knowledge, induces us to hold them 
in high elfeem ; but, in conlequence of the time and la¬ 
bour we have bellowed upon them, we are apt to carry 
this too far. There is alfo a certain jealoufy of our con¬ 
temporaries, which leads fome, who cannot cope with the 
moderns, to praife the ancients at their expenfe. We 
mull however candidly acknowledge, that the ancient 
models of tafte have never been equalled. 
The oppolite to this, is the prejudice in favour of Ab- 
velty. There have been times when the prejudice in fa¬ 
vour of the ancients has funk, particularly in the begin¬ 
ning of the 18th century, when the celebrated Fontenelle 
took part with the moderns. In experimental knowledge, 
which is always capable of being extended, it is very na¬ 
tural that wefhould place more confidence in the moderns 
than in the ancients. But this judgment muft be confi- 
dered as a preliminary judgment ; for, if we change it 
into a definitive one, it then becomes a prejudice. 
We mull not omit to mention two very ufeful rules in 
judging : the one is, that companions illuflrate, but do 
not prove : and the other, that ridicule expofes, but does 
not refute. 
2. The Prejudice of Self-Love , or logical Egotifm, is op- 
pofed to the Prejudice of Authority, as it manifelts itfelf in 
a certain partiality to the offspring of our own underftand- 
ings. But felf-love is extremely laudable, as it induces 
us to be allive for our own intereft, and is even neceflary 
to our exillence. How, then, does it come to be the 
fource of prejudice? This happens when we confult our 
felf-love at the expenfe of our Reafon. A ilritil attention 
"to the following maxim, will eventually confine felf-love 
within its proper limits, and thus prevent its ever amount¬ 
ing to a prejudice. We fhould always alk ourfelves this 
Quetlion : Would every body judge as / have done? and, if 
this were to become a univerfal law for all reafonable beings, 
what would be the Jlate of the world? 
To favour the prejudices of others, is nothing more 
than directly to impofe upon them.' Yet who would un¬ 
dertake to expofe and remove them ? Old and inveterate 
prejudices are difficult to be eradicated, being judges in 
their own caufe. It is however very advifeable to ule 
every means to expofe them, as much good may refult 
from their extermination. 
V. Of Probability.—Difference between Probability and Plau- 
fbility—Mathematical and P hilofophical Probability .— 
Doubt Subjeflive and Objective. — Sccpticifm, Dogmatifm, and 
Criticifm. — Hypothfis.—Of the Difference between Theoretical 
and Practical Knowledge. 
When there is a majority of objective reafons in favour 
of a thing, it approximates to Certainty, and is termed 
Probability. For inllance, if a medicine lias cured ten and 
killed ten, there is then an equal chance ; but, if it has 
cured twenty and killed ten, the reafons for are more than 
thofe againfl it. If it has cured a hundred and killed 
ten, the probability in its favour is greaterj but, if it has 
cured ten thoufand and killed only ten, the probability 
of its effefling a cure is greatly increafed. Hence it 
is evident that probability is fufceptible of degrees. 
The more perfeft our conceptions of a thing are, the bet¬ 
ter we are able to judge of its probability : For example, 
fuppofe I throw two dice, what is it moll probable I (hall 
throw, ten or five? Firlt, I have an accurate conception 
of the dice ; they are cubes, with the numbers from one 
to fix marked on each. In order to determine which 
throw is the moll probable, I proceed to enumerate all 
the poflible throws thus; Let A reprefent one Die, and 
B the other. 
Now there are only thirty-fix poflible cafes : And thus, 
by a complete analyfls cf our Conception of the Dice, we 
have obtained the exa£t number of poflible cafes to pro¬ 
duce each throw ; by which we perceive, that to throw- 
five we have four poflible cafes, and to throw ten we have 
only three ; confequently it is more probable to throw the 
former. Hence it is evident, that, the clearer our concep¬ 
tions are, the more accurately we are able to judge, till at 
length we may count the different degrees of probability, 
which is of the utmoft importance to the fuccefs of an 
undertaking. 
Probability is not to be met with in the Mathematics, for 
there demonstration commands aflent; nor in True Philofo- 
phy, (Criticifm,) for here we muft either believe or know. 
By the former is meant Rational belief, which is a fubjec- 
tively-fufticient holding for true; and to know is to be 
fully certain. Probability is therefore only to be met with 
in experience. 
By Probability is to be underftood a holding for true on 
infufficient grounds, which however have agreater relation 
to the fufficient than to the oppofite. In this explanation 
we diftinguifli Probability from mere Plaufibility (verifimili- 
tudo) ; that is, a holding for true upon infufficient grounds 
which have a greater relation to the infufficient than to the 
oppofite. The grounds of holding for true may be either 
objectively ox fubjeclively greater than thofe for the contrary. 
In order to difcover which of the two is the cafe, we need 
only compare the grounds with the fufficient ground. In 
Probability, {he ground of holding for true is objectively va¬ 
lid ; in mere Plaufibility, it is only fubjeClively fo. In Pro¬ 
bability, there muft always be a llandard by which it can 
be eftimated ; and this is Certainty ; for, if we are to com¬ 
pare the infuffeient with the fufficient, we muft know what 
is fufficient, namely, the Certainty. In Plaufibility there 
is no fuch ftandard j for here we do not compare the infuffi- 
cient with the fufficient ground, but with the oppofite. 
The moments ofProbability may be either homogeneous or 
heterogeneous.* 
