ASSENT. - An essential moment of judgment (v.), consisting in the act by which the mind adheres to a proposition, that is, affirms the relation of unity or distinction that exists between subject and predicate. The term derives from the Latin assensus, by which, in later usage and in a technical sense, the Greek term συγκατάθεσις was rendered; Cicero translates it with adsensio or adprobatio, and, attributing its introduction to Zeno, defines it as the wholly voluntary act by which the mind assents to the content of an evident representation (φαντασία), called by Zeno himself comprehensive (καταληπτική) and which, "once accepted and approved" (συγκατάθεσις), was called by him "comprehension" (κατάληψις) (Cicero, Acad., I, 40, and in general H. Ritter and L. Preller, Historia philosophiae graecae, 10th ed., Gotha 1934, §§ 484-86).
Contrary to the Cartesian thesis, assent is an act exclusive to the intelligence, and is distinguished from the consent of the will, which is rather an adherence of an affective order of the will to the truth intuited and affirmed by the intellect. The distinction, however, is almost neglected by common usage, which, not naturally distinguishing the various analytical moments of judgment, understands assent synthetically as the intellectual-volitional adherence to a given proposition. In this sense dissent is opposed to assent, although, logically, every critical act of thought is always affirmation, and therefore assent. According to the varied content of judgment, assent can be certain-opinative, true-erroneous. Particular questions are raised by assent not founded on the evidence of the relation between subject and predicate but on extrinsic authority (v. FEDE).
In legal language, the act of will of one who, not being the author or a party to a juridical act, must, by law, complete the will of these so that the act be valid, is often called assent.
Bibliography
Ugo Viglino