Institutio Oratoria

I now turn to arguments, the name under which we comprise the ἐνθυμήματα, ἐπιχειρήματα, and ἀποδείξεις of the Greeks, terms which, in spite of their difference, have much the same meaning. For the enthymeme (which we translate by commentun or commentatio, there being no alternative, though we should be wiser to use the Greek name) has three meanings: firstly it means anything conceived in the mind (this is not however the sense of which I am now speaking);

secondly it signifies a proposition with a reason, and thirdly a conclusion of an argument drawn either from denial of consequents or from incompatibles [*](v. viii. 5; xiv. 2. n.) ; although there is some controversy on this point. For there are some who style a conclusion from consequents an epicheireme, while it will be found that the majority hold the view that an epicheireme is a conclusion from incompatibles: [*](See v. xiv. 2, VIII. v. 9.) wherefore Cornificius styles it a contrarium or argument from contraries. Some again call it a rhetorical