  On most topics the Perutilis logica (a text based on lectures first given before 1356 and finally revised for publication before 1360) is influenced by Ockham’s Summa logicae, though it offers an independent approach in the treatises on obligations, insolubles, and consequences, which had assumed greater importance during this period. As has been known for some time, this work is a remarkable handbook organized into six treatises: the first defines the elements of propositions; the second treats of the properties of terms; the third of the truth conditions of different types of proposition; the fourth of consequences (including syllogisms, and in fact adding to it the theory of topics); the fifth of fallacies; and the sixth of insolubles and obligations. 