Thus we are left with six moods which are valid in the first figure, namely,
AAA. EAE. AII. EIO. AAI. EAO.
FIGURE II.
§ 624. The rule that one premiss must be negative excludes four moods, namely, AAA, AAI, AII, IAI. The rule that the major must be universal excludes OAO. Thus we are left with six moods which are valid in the second figure, namely,
EAE. AEE. EIO. AOO. EAO. AEO.
FIGURE III.
§ 625. The rule that the conclusion must be particular confines us to eight moods, two of which, namely AEE and AOO, are excluded by the rule that the minor premiss must be affirmative.
Thus we are left with six moods which are valid in the third figure, namely,