If someone objects, “You have made the impossibility of seeking (simple conceptions) a necessary concomitant of each of the two contradictories, yet contradictories can neither coexist nor simultaneously be absent. Now, whenever the consequent disappears, the antecedent must disappear as well; therefore, if the impossibility of inquiry—the consequent—were absent, the two contradictories would have to be absent, and the absence of both contradictories is impossible,” we reply: This impossibility is a necessary concomitant on the assumption of either contradictory. Whichever of the two is in fact realized, the impossibility is inseparably linked to it in reality. Hence there is neither a combining of contradictories nor a joint elimination of them. Indeed, this strengthens the point at issue: if the negation of this impossibility leads to an absurdity, then the impossibility cannot be negated; it must hold. And because the negation of this impossibility would entail the simultaneous presence of both contradictories—an impossibility—its opposite, namely the existence of the impossibility, is true. Thus the impossibility of seeking simple conceptions stands confirmed, which is precisely what was intended.

Now, if simple conceptions are not subject to inquiry, they must either already be present to a person’s mind—in which case they are not acquired through definition, and definition adds nothing to one’s grasp of them—or they are absent; yet the mere formulation of a definition does not, by itself, make someone who does not know the names conceive the things so named. Once a person has even the least awareness of them, he no longer needs the definition for that awareness, any more than he needs the name itself.

The aim, therefore, is to equate the benefit of definitions with the benefit of names. When a definition contains several words, it is like having several names, whether those words are derived or not.

Sixth Consideration: The distinction between essential and accidental predicates is unsound.

They say that what yields a grasp of a thing’s reality is the complete—or “real”—definition, which is composed of genus and specific differentia, predicates that are essential, both common and distinctive. Accidental predicates, such as the common accident and the proprium, do not serve this purpose. The standard illustration is