 The repetitive (istiṯnāʾī) syllogistic covers inference patterns such as modus ponens and modus tollens (in their conditional and disjunctive variants). It constitutes the other major division of the syllogistic along with the connective (iqtirānī) syllogistic and seems to be regarded by Avicenna as somehow dependent on it (a systematic discussion of the reducibility of the former to the latter occupies part of Qiyās IX.1, where Avicenna discusses among other things the idea that the major premise of modus ponens may be in a sense redundant).