To provide for the memorization of the useful modes of syllogisms, the “Schoolmen” (i.e., Scholastic Catholic philosophers of the middle ages) created a system of names. In his translation of Aristotle’s Prior Analytics, Thomas Taylor provides a helpful explanation of this system, which is provided below.
The quantity of a proposition, so far as pertains to syllogism is twofold, universal and particular. And it must be observed, that a universal affirming proposition has the symbol A; a universal denying proposition E; a particular affirming proposition has the symbol I; and a particular denying proposition, the symbol O.
The distinct modes.of syllogisms are sixteen, which being multiplied according to triple figure, make forty-eight. But of these sixteen, eight are entirely useless, viz. E E, E O, I E, I I, I O, O E, O I, O O. The remaining eight are useful; viz. A A, A E, A I, A O, E A, E I, I A, O A; and they are so disposed in figures, that four modes are contained in the, first, four in the second, and six in the third figure; all of them being direct. These are contained in the following barbarous terms invented by the schoolmen:
- Barbara, Celarent, Darii, Ferii;
- Cesare, Camestres, Festino, Baroco;
- Darapti, Felapton, Disamis, Datisi, Bocardo, Ferison.
In these words, three syllables signify as many propositions; the first syllable signifying the major proposition; the second syllable signifying the minor proposition; and the last syllable signifying the conclusion.
First Figure
- Barbara
Every B is A. (bAr)
Every C is B. (bA)
∴ Every C is A. (rA) - Celarent
No B is A. (cE)
Every C is B. (lA)
∴ No C is A. (rEnt) - Darii
Every B is A. (dA)
Some C is B. (rI)
∴ Some C is A. (I) - Ferio
No B is A. (fE)
Some C is B. (rI)
∴ Some C is not A. (O)
Second Figure
- Cesare
No A is B. (cE)
Every C is B. (sA),
∴ No C is A. (rE) - Camestres
Every A is B. (cA)
No C is B. (mE)
∴ No C is A. (strEs) - Festino
No A is B. (fEs)
Some C is B. (tI)
∴ Some C is not A. (nO) - Baroco
Every A is B. (bA)
Some C is not B. (rO)
∴ Some C is not A. (cO)
Third Figure
- Darapti
Every B is A. (dA)
Every B is C. (rAp)
∴ Some C is A. (tI) - Felapton
No B is A. (fE)
Every B is C. (lAp)
∴ Some C is not A. (tOn) - Disamis
Some B is A. (dI)
Every B is C. (sA)
∴ Some C is A. (mIs) - Datisi
Every B is A. (dA)
Some B is C. (tI)
∴ Some C is A. (sI) - Bocardo
Some B is not A. (bO)
Every B is C. (cAr)
∴ Some C is not A. (dO) - Ferison
No B is A. (fE)
Some B is C. (rI)
∴ Some C is not A. (sOn)
Therefore, there are also five indirect modes in the first figure: Baralipton, Celantis, Dabitis, Fapesmo, Frisesmorum.
God bless your studies,
Mr. William C. Michael, O.P.
Headmaster
Classical Liberal Arts Academy
