syllogism rather than a complete syllogism, is purely conventional and has no rational basis—just as they distinguished between essential attributes and accidental attributes inseparable from essence and existence through similarly arbitrary stipulations.

It thus becomes clear that, in what they call “definition” and “demonstration,” these people have relied neither on an existing reality nor on anything rationally intelligible, but merely on convention. This resembles the dispute over the term “cause”: does it designate that which necessarily entails its effect, such that the effect never fails to follow under any circumstances, admitting neither a contrary instance nor exceptions? Or does it designate that which tends to produce the effect, although the effect may fail to follow because a condition is absent or an impediment is present?

Likewise, some practitioners of rational inquiry and disputation use the term “proof” for that which unconditionally entails its conclusion, so that the absence of countervailing evidence is included within it. Others use “proof” for that which is such as to entail its conclusion, its failure to do so arising only because a condition is absent or an impediment is present.

Practitioners of disputation have also disagreed over whether someone presenting an argument must, when stating the proof, clarify countervailing evidence in general or in detail wherever detail is possible; whether he need address it neither in general nor in detail; or whether he must clarify it in general but not in detail. These are stipulated conventions, comparable to the words people agree upon to express what is in their minds. They are not independently established truths concerning intelligible matters on which nations agree, as these people claim for their logic.

Indeed, those who use “cause” and “proof” in one or the other of these senses are closer to reason than those who maintain that a proof can consist of only two premises. For this singles out one number rather than another without any justification, whereas the former