 Avicenna discusses various combinations (taʾlīfāt) of syllogisms, identified first on the basis of their major and minor premises, and then differentiated according to the other parameters. Individual moods, in analogy with categoricals, are identified in function of the quality and quantity of their (hypothetical) premises. The combinations are accordingly distributed into two main groups. In the first group, syllogisms have a disjunctive major and a conditional minor. In the second group, syllogisms have a conditional major and a disjunctive minor.