V. RATIO COMMUNIS AND RATIO PROPRIA^{1}

We have suggested that the ratio propria of a term comprises the res significata and the usual, familiar mode of signifying it and that the ratio propria is discoverable by looking for that mode of signifying which enters into the other modes of signifying the same res significata. But we often find St Thomas speaking of the ratio communis of the analogous name. How, we must ask, does such a common notion relate to the proper notion of the same name? Let us approach the problem by getting hold of a distinction of common and proper notions in things named univocally. It seems clear that things are considered to be named univocally with respect to a name signifying a common notion; if that name is generic not all such things would be considered to be named by a word signifying a subalternate proper notion. That is, some things may be considered to be named univocally by animal which would not be named by man. We are calling what animal signifies a ratio communis, what man signifies a ratio propria. Since the proper notion is not a meaning of the generic term, this distinction between common and proper notions involves different names and not one name.^{2} In the case of things named analogously, it is the same name whose ratio communis is apparently opposed to its ratio propria, and while the name does not change there seems to be suggested an appropriation, a shrinking, as it were, of the common notion.

    Let us pose this question with reference to sanum. The ratio propria would seem to be "subject of the quality, health." Would the ratio communis then be, "related in some way to health." In the case of ens, the proper notion is "id cui debet esse in se et non in alio" and the common notion habens esse in whatever mode. The common notion is a kind of blank check, almost a propositional function: "existence (x)". Scotus, noticing this, felt that ens could be univocally common to substance and accidents but the great difficulty with that suggestion is that it fails to take into account that we want the mode of signification to vary as we predicate the term. What permits us to speak of the ratio communis of the analogous name is the res significata; what prevents this common notion from giving rise to univocation is the fact that the things denominated from the form are not denominated in the same way; they are unequal with respect to what the name principally signified.^{3} As predicated, the analogous term must always involve some mode of signifying as well as the denominating form and, unless otherwise specified, this will constitute the ratio propria. The proper notion, again, will relate to the common notion as what states the usual or more obvious mode of the form in question. For this reason, Aristotle and St Thomas hold that he would would study being as being must, since being is analogous, chiefly concern himself with the principal mode of being, substance.

{1} Cf. "The ratio communis of the Analogous Name," Laval theologique et philosophique, vol. XVIII, no. 1 (1962), pp. 9-34 and Supra, Chap. 1.

{2} But what are we to make of those not infrequent cases where the same word is used as genus and to signify one of the species of that genus, e.g. "anima" as generic name but also used as the name of a species of animal? Since in the two cases "animal" is imposed from different res significatae, this is a case of equivocation.

{3} "Sed dicendum est quod unum dividentium aliquod commune potest esse prius altero dupliciter: uno modo, secundum proprias rationes, aut naturas dividentium; alio modo, secundum participationem rationis illius communis quod in ea dividitur. Primum autem non tollit univocationem generis, ut manifestum est in numeris, in quibus binarius secundum propriam rationem naturaliter est prior ternario; sed tamen aequaliter participant rationem generis sui, scilicet numeri: ita tamen et ternarius multiudo mensurata per unum, sicut et binarius. Sed secundum impedit univocationem generis. Et propter hoc ens non potest esse genus substantiae et accidentis: quia in ipsa ratione entis, substantia, quae est ens per se, prioritatem habet respectu accidentis, quod et ens per aliud et in alio." - In I Periherm., lect. 8, n. 6.

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