 Ockham’s Summa Logicae is thought to date to the first years of the 1320s; section 3 of Part III is entirely dedicated to consequences. In chapter 1 of III-3, Ockham presents a somewhat confusing account of consequences based on nine distinctions, including the simple vs. as-of-now distinction; the distinction between formal and material consequence is the last one  presented.[9]  It seems that this important distinction was discussed systematically for the first time in this very text (Martin 2005), but Ockham offers virtually no justification for his use of the notions of form and matter with respect to consequences. It is also possible that Ockham deliberately ignores the well-entrenched distinction between natural and accidental consequences, given that he mentions nine distinctions, but not this one. Here is how Ockham introduces the notion of a formal consequence: