MOOD, or Mont!, in logic, called also syllogistic mood, a proper disposition of the several propositions of a syllogism, in respect of quantity and quality.
As in all the several dispositions of the middle term, the propositions of which a syllogism consists may be either univer sal or particular, affirmative or negative ; the (Inc determination of these, and put ting them together as the laws of aug mentation require, constitute what logi cians call the moods of syllogisms. Of these moods : here are a determinate num ber to every figure, including all the pos sible ways in which propositions differ ing in quantity or quality can be com bined, according to any disposition of the middle term, in order to arrive at a just conclusion. There are two kinds of moods, the one direct, the other in direct.
The direct mood is that wherein the conclusion is drawn from the premises, directly and immediately, as, "Every ani mal is a living thing; every man is a liv ing animal ; therefore every man is a liv ing thing." There are fourteen of these direct moods, fou r whereof bolong to the first figure, four to the second, and six to the third. They are denoted by so many artificial words framed for thatpurpose, viz. 1. Barbara, celerent, darii, ferioque. 4. Baralip, celantes, dabitis, fapesmo, fri sesom. 2. Cesare, camestres, festino, ha roco. 3. Darapsi, selapton, disainis, da
tisi, bocardo, ferison. The use and effect of which words lie wholly in the syllables, and the letters whereof the syllables con sist ; each word, for instance, consists of three syllables, denoting the three propo sitions of a syllogism, viz. major, minor, and conclusion : add, that the letters of each syllable are either vowels or conso nants ; the vowels are A, which denotes an universal affirmative ; F., an universal negative ; 1, a particular affirmative; and 0, a particular negative : thus Barbara is a syllogism or mood of the first figure, consisting of three universal affirmative propositions. Baralip, one of the fourth figure, consisting of two universal affirm ative premises, and a particular affirma tive conclusion. The consonants are chiefly of use in the reduction of syllo gisms. The direct mood, is that where in the conclusion is not inferred immedi. ately from the premises, but follows from them by means of aconversion, as, "Eve ry animal is a living thing ; every man is an animal ; therefore some living thing is a man." Moon, or Mona, in grammar, the dif ferent manner of conjugating verbs, serv. ing to denote the different affections of the mind. See GRAMMAR.