Peri ermēneías

...and some, finally, although they are truly said as a composite unity, are not truly said separately. At this point, it will also be necessary to deal with those propositions which they call identical, in which there is the greatest contradiction antiphasis; in which also the greatest ignorance agnoia is placed, when a thing is denied to be itself. In this way, all fallacies of composition synthesis and division diairesis in enunciations will be avoided, as well as homonymies in both the subject and the predicate; those who do not notice these in enunciations (in which truth and falsehood are first discerned) should not be surprised that they err in syllogisms, which are constructed from enunciations.

4th Part. Finally, the truth of the axiom (the affirmation or negation of everything παντὸς κατάφασις ἢ ἀπόφασις) must be observed in modified enunciations, which are of the possible being tō dunaton einai and not possible mē dunaton; contingent being endechomenon einai and not contingent mē endechomenon; and concerning the impossible peri tō adunatō and necessary anankaio.

5th Part. Lastly, since truth and falsehood are contraries in enunciations, and falsehood is not opposed to truth in only one way, it must be seen which enunciations are most opposed in terms of truth and falsehood. At this point, it will also be necessary to speak of the highest truth of enunciations and the highest opposed falsehood, so that it may be noticed what the greatest ignorance agnoia is in enunciations, namely that by which a thing is denied to be itself contradictorily antiphatikos.

Having exposed these things, as in a sketch hōs en tupō, the most perfect and absolute doctrine of enunciating has been outlined.