26 L O 
ledge mud be the ground of the dependence of another 
upon it; or, laftly, it muft regard the connection of the 
parts into a whole; a logical divijinn. Hence there can 
only be three forts of Univerfal Rules, that is, major pro¬ 
portions, by which one judgment can be deduced from 
another. 
Remark (i.) Rational conclufions cannot be diftin- 
guithed according to Quantity, for every major is a Rule, 
confequently Univerfal ; nor with refpect to Quality, for 
it is indifferent whether they affirm or deny-, nor, laftly, 
with refpeft to Modality, for the conf'equence is always 
accompanied with the confcioufnefs of Necefftty, and has 
the dignity of an apodictical propofition. It muff be evi¬ 
dent, therefore, that Relation is the only poffible ground 
of divifion of Rational Conclufions. 
(2.) Some logicians have confidered the Categorical 
Conclufions of Reafon as the only legitimate ones; the 
other two as illegitimate. But this is extremely errone¬ 
ous ; for all three are equally correft, and effentially-dif- 
ferent Functions of Reafon. 
Peculiar Difference of Categorical, Hypothetical, 
and Disjunctive, Conclufions of Reafon. 
61. The difference in the three forts of Conclufions of 
Reafon lies in the Major propofition. In Categorical con¬ 
clufions, the major is a Categorical propofition ; in Hypo¬ 
thetical, it is an Hypothetical or Problematical propofition ; 
and, in Disjunctive, it is a Disjunctive propofition. 
I. Categorical Conclufions of Reafon. 
62. In every Categorical Conclufion of Reafon, there 
are three principal Conceptions, (termini;) namely. 
1. The Predicate in the conclufion, which is called Ter¬ 
minus major, becaufe it has a larger fpliere than the fubject; 
2. The SubjeCl in the conclufion, which is called Ter¬ 
minus minor ; and, 
3. An intermediate conception, which is called the mid¬ 
dle term, becaufe, by means of it, a certain knowledge is 
ranked under the condition of the rule. 
Remark. The above-mentioned difference in terms oc¬ 
curs only in Categorical Conclufions of Reafon ; for thefe are 
the only ones that conclude by means of a middle term-. 
the others by a propofition being reprefented Problemati¬ 
cally in the major, and Afferiorically in the minor. 
Principle of Categorical Conclufons of Reafon. 
63. The principle upon which the pofTibility and vali¬ 
dity of all Categorical Conclufons of Reafon refts is this : 
What applies to the mark of a thing , applies alfo to the thing it- 
felf \ What contradicts the mark of a thing, contradicts aljo the 
thing itj'elf. (Nota notas eft nota rei ipfius ; repugnans 
notas, repugnat rei ipfi.) 
Remark. From the preceding principle is eafily derived 
the well-known rule of DiClum de omni et nullo ; but, for 
that very reafon, it cannot be the higheft principle for 
rational conclufions in general, nor for categorical in par¬ 
ticular. Genus and Species are univerfal marks for all thofe 
things which ftnnd under them. Hence the following 
Rule : What applies to or contradiCls a Genus or a Species, that 
alfo applies to or contradiCls all thofe objeEls which [land under 
that Genus or Species ; and this is the rule called the DiClum 
de omni et nullo. 
Rules for Categorical Conclufions of Reafon. 
64. From the nature and principle of Categorical Con¬ 
clufions of Reafon, flow the following Rules. 
1. In every Categorical Rational Conclufion there can 
be contained neither more nor lefs than three principal con¬ 
ceptions, (termini;) for here we mull connect two concep¬ 
tions (the fubjeft and predicate) by a mediating mark, or 
middle term ; 
2. The premifes cannot be altogether negative, (ex puris 
negativis nihil fequitur;) for the fublumption in the mi¬ 
nor propofition nuift be affirmative, as it affierts that a 
certain knowledge ftands under the condition of the rule ; 
3. Neither can the premifes be altogether particular., (ex 
G I C. 
puris particularibus nihil fequitur ;) for then there would 
be no rule, that is, no univerfal propofition, from which 
a particular knowledge could be deduced; 
4. The conclufion always accommodates itfelf to the weaker 
part of a Ratiocinatun , that is, either to the negative or 
particular propofition in the premifes; (conclufio fequitur 
partem debiliorem :) therefore, 
5. If either of the premifes be a negative propofition. 
then the conclufion mu ft alfo be negative ; and, 
6. It one ot the premifes be a particular proDofition, 
then the conclufion rnuft alfo be particular. 
7. In all Categorical Syllogifms, the major muft be a uni¬ 
verfal propofition, the minor an affirmative propofition 
Hence, laftly, ‘ 1 
8. The Conclufion muft agree in refpeit to Quality with 
the major, and in refpeft to Quantity with the minor. 
Pure and Mixed Categorical Conclufions of Reafon. 
t &S- f. c.ategorical Rational Conclufion is pure, when no 
immediate conclufions are introduced into it, nor the regu¬ 
lar order of the premifes changed. Otherwife the con¬ 
clufion is called impure, or mixed ; (ratiocinium, five hy¬ 
brid uni.) 
Mixed rational Conclufions by Inverfwn of the Propofitions. 
66. To the mixed conclufions are reckoned thofe which 
arife by inverfion of the propofitions, and in which there-: 
fore the placing of thefe propofitions is irregular. This 
takes place in the three IqJl divifions of the Table of In¬ 
verfion of the Propofi.ions of Categorical Rational Con¬ 
clufions: therefore th e firft is the only regular and legiti¬ 
mate mode of concluding. 
Explanation of the Table of the four Figures of Conclufons, 
67. By figures is to be underfiood the four modes of 
Concluding, whofe difference confifts in the particular 
placing of the premifes and of their conceptions. The 
inveftigation of thefe figures is the more necefl'ary, as lo¬ 
gicians have dwelt much upon them, becaufe they found 
that true confequences have followed from them, though 
in a concealed and circuitous way -. for ft riel logical confe¬ 
quences can only flow dircftly from the firft figure. 
Ground of the Difference in the four Figures, by means of the 
different placing of the Middle Term. 
68. Upon the proper placing of the middle term every 
thing here depends. It may occupy either, 1, in the ma¬ 
jor the place of the fubjedl, and in the minor the place of 
the predicate-, or, 2, in both premifes, the place of the 
predicate ; or, 3, in both premifes, the place of the fubjeft ; 
or, laftly, 4, in the major the place of the predicate, and 
in the minor the place of the fubjedt. By thel'e four cafes 
the difference of the four figures is determined. For 
inllance, let S ftand for fubjtdt in the conclufion, P for 
predicate, and M for middle term. Then the fcheme of 
the fourfigures may be exhibited in the following Table: 
M. P. 
S. M. 
P. M. 
S. M. 
M. P. 
M. S. 
P. M. 
M. S. 
S.P. 
S. P. 
S. P. 
S. P. 
Rules for the Firft Figure, as the only regular one. 
69. The rule for the firft figure, as the only regular and 
legitimate mode of Categorical Conclufion, is That the 
Major rnuft be a univerfal propofition, the Minor an affir ¬ 
mative. And, as this mult be the univerfal rule for all 
Categorical Rational Conclufion, hence it follows, that the 
firft figure is the only regular one: it is the ground-work 
of all the others ; fo that, if any of them conclude rightly, 
they muft be reducible to the firft, by means of the in¬ 
version' 
