 As for material consequences, it is not entirely clear how exactly Ockham intended to define this class of consequences. He says that material consequences are those that hold in virtue solely of (the meaning of) their terms (Ockham, Summa Logicae III-3, ch. 1, lines 55–57) but the two examples he gives are of a consequence with an impossible antecedent and a consequence with a necessary consequent. This suggests the reading that this category consists exclusively of consequences of this sort (ex impossibili and ad necessarium consequences), but there is no conclusive evidence supporting this interpretation; in particular, he did not offer any explicit motivation for his use of the concept of matter to characterize this class of  consequences.[10]