"For a thorough understanding of the syllogism we need to understand it not only with respect to its definition but also with respect to its divisions. Some of the divisions that must be presented apply to the syllogism in general –e.g., a syllogism is either perfect or imperfect, either affirmative or negative, and so on. However, other divisions that must be presented apply to the syllogism in such a way as to separate it into distinct types. The following division is of this kind: as syllogism is either demonstrative, or dialectical, or sophistical. A demonstrative syllogism is the one that produces scientific knowledge on the basis of necessary [premises] and the most certain reasons for the conclusion. A dialectical syllogism, however, is the one that produces opinion on the basis of probable [premises]. Finally sophistical syllogism is the one that either syllogizes on the basis of seemingly probable [premises] or seemingly syllogizes on the basis of probable [premises]; in either case it is strictly aimed at glory or victory."