Part III, Chapter 8: Of the Moods of the Fourth Figure
Rule 3
In the negative moods the major proposition must be general.
For the conclusion being negative, the greater term is there taken generally. It must, therefore (by the second general rule), be also taken generally in the premises. Now it is here, as in the second figure, the subject of the major, and consequently it must, as in the second figure, being taken generally, render the major general.
That there can be no more than five moods in the fourth figure.
Of the ten valid moods, A, I, I, and A, O, O, are excluded by the first rule; A, A, A, and E, A, E, are excluded by the second; O, A, O, by the third.
There remain, therefore, only these five: —
2 affirmative: A, A, I; I, A, I. 3 negative: A, E, E; E, A, O; E, I, O.
These five moods may be embodied in the following artificial words: —
BAR- All the miracles of nature are common; DA- Whatever is common does not arrest our attention; RI. Some things, therefore, which do not arrest our attention, are miracles of nature. CA- All the evils of life are transitory evils; LEN- No transitory evils are to be feared; TES. Therefore none of the evils that are to be feared are evils of this life.
Di- Some fools speak the truth; BA- Whoever speaks the truth deserves to be imitated; TIS. Therefore there are some who deserve to be imitated, who are nevertheless fools.
FES- No virtue is a natural quality; PA- Every natural quality has God for its author; MO. Therefore there are qualities which have God for their author, which are not virtues.
FRE- No miserable man is content; SI- Some are content who are poor; SOM. Therefore there are poor people who are not unhappy.
It is well to state that these five moods are commonly expressed in this way, Baralipton, Celantes, Dabitis, Fapesmo, Frisesomorum. This arose from the fact that Aristotle never having made a separate figure for these moods, they were regarded as only indirect moods of the first figure, since it was maintained that their conclusion was reversed, and that the attribute was the real subject. Hence, those who have followed this opinion, have placed as the first proposition, that which contains the subject of the conclusion, and as the minor, that which contains the attribute. Thus they have given nine moods to the first figure, four direct, and five indirect, which they have included in these two verses:
Barbara, Celarent, Darii, Ferio, Baralipton. Celantes, Dabitis, Fapesmo, Frisesomorum.
And for the other two other figures —
Cesare, Camestres, Festino, Baroco; Darapti, Felapton, Disamis, Datisi, Bocardo, Ferison.
But as the conclusion is always supposed, since it is that which we design to prove, we cannot say properly that it is ever reversed; we, therefore, thought it better to take always, as the major, the proposition into which the attribute of the conclusion enters, which obliged us, in order to put the major first, to reverse these artificial terms, so that, for the better retaining of them, we may include them in this verse: —
Barbari, Calentes, Dibatis, Fespamo, Frisesom.
Of the different Sorts of Syllogisms.
From all that we have just said, it may be concluded that there are nineteen kinds of syllogisms, which may be divided in different ways.
4. According to the different figures, in subdividing them by moods, which has already been sufficiently done, in the explanation of each figure.
5. Or, on the contrary, according to the moods, in subdividing them by the figures, where we shall still find nineteen species of syllogisms, since there are three moods, each of which only concludes in a single figure; six, each of which is valid in two figures, and one which is valid in all the four.