© Proceedings of the Society for Medieval Logic and Metaphysics, Volume 7, 2007 Joshua P. Hochschild: Cajetan on Scotus on Univocity, pp. 32-42. Joshua P. Hochschild: Cajetan on Scotus on Univocity What role does Scotus's understanding of univocity play in Cajetan's development of a theory of analogy? In this paper I examine three relevant texts from Cajetan – question 3 of his commentary on Aquinas's De Ente et Essentia, his treatise De Nominum Analogia, and his commentary on question 13, article 5 of Aquinas's Summa Theologiae – in which Cajetan articulates his understanding of analogy at least in part through dialectical engagement with Scotus's arguments about univocity. It is not my intention to evaluate the fairness of Cajetan's interpretation or deployment of Scotus's position, or to say whether the arguments Cajetan considers are in fact representative of Scotus's views – that I will leave to more competent scholars of Scotus. 1 Rather, I want to illuminate the function that, in Cajetan's mind, certain theses and arguments associated with Scotus play in formulating problems that Cajetan's theory of analogy proposes to solve. Some influence of Scotus (and Scotists) in the development of Cajetan's analogy theory is widely acknowledged. Also well known is the influence of Cajetan on the subsequent history of Thomistic reflection on analogy. In recent generations of scholarship – thanks in part to arguments from influential Thomistic philosophers (like Étienne Gilson) and thanks also to discussions among theologians about the significance of the analogia entis – Cajetan is often criticized for a position that was so preoccupied with Scotus's approach as to be (inadvertently) coopted by it. According to a common version of this criticism, Scotus's arguments provoked Cajetan to become preoocupied with analyzing the analogical ―concept,‖ while a more authentically Thomistic approach would have treated analogy instead as a matter of ―judgment.‖ 2 This trend of criticizing Cajetan for a ―conceptualist‖ or even ―univocalist‖ account of analogy provides the background for my reflections on Cajetan's use of arguments from Scotus about univocity. One of the lessons of my analysis is that this common criticism of Cajetan is misplaced. Cajetan is indeed concerned to answer particular problems 1 On the side of philosophical theology, one might start with Alexander W. Hall, Thomas Aquinas and John Duns Scotus: Natural Theology in the High Middle Ages (Continuum, 2007), esp. chs. 4-7. On the side of logic and semantics, see Giorgi Pini, Categories and Logic in Duns Scotus: An Interpretation of Aristotle's Categories in the Late Thirteenth Century (Leiden: Brill, 2002). 2 For references and discussion, see Joshua P. Hochschild, ―Analogy, Semantics, and Hermeneutics: The  Concept vs. Judgment' Critique of Cajetan's De Nominum Analogia,‖ Medieval Philosophy and Theology 11 (2003): 241-260. 33 raised by Scotus, but in doing so he refuses to adopt, and pointedly criticizes, key semantic assumptions behind Scotus's position. Furthermore, Cajetan's response to Scotus confirms that while he intended to answer semantic or ―conceptualist‖ objections with his own alternative semantic analysis of analogy, Cajetan saw that the Thomistic disagreement with Scotus could not be addressed only at the semantic level but depended ultimately on distinctions at the level of metaphysics. The Commentary on De Ente et Essentia (1495) Proceeding in chronological order, I will discuss first Cajetan's commentary on Aquinas's treatise De Ente et Essentia. Composed in 1495, this is a fairly youthful work – Cajetan was 26 years old. Recently appointed to the Chair of Thomistic Metaphysics at the University of Padua, Cajetan's expected duties would have included criticism of Scotistic views. Indeed, while Cajetan comments line by line, his commentary is interspersed with extended questions which often address particular issues where Thomists differed from Scotists (e.g. on the first object of intellection, on individuation, etc.). Cajetan engages Scotus on univocity in question 3: Whether being is predicated univocally of substance and accident, or primarily of substance (sect. 17 – 21). In elaborating on the question (sect. 18) Cajetan makes clear that what is at stake is not primarily a metaphysical issue, but a semantic or epistemological one. As Cajetan puts it, analogy can be considered according to the being of the predicates (secundum esse illius praedicati), when a predicate has being in different things with an order of priority; this occurs even for a genus term when its species have an order of priority, such as higher or lower orders of animals. (Cajetan cites Aristotle's Metaphysics, Book XII, and in De Nominum Analogia he will call this ―analogy of inequality.‖) Analogy in the sense that Cajetan wants to consider it is not according to this order in reality, but according to an order in intelligible content: it is when a word is predicated ―per prius et posterius secundum rationem propriam.‖ This occurs when a word, predicated of two (or more) things, has a primary ratio when predicated of one, and a ratio somehow related to that primary ratio when predicated of the other (or others). The classic example, which Cajetan here uses, is ―healthy‖: it's primary meaning pertains to the health of the animal; its secondary meanings pertain to what is related to this primary meaning, as ―healthy‖ predicated of urine, diet, and medicine signify respectively relations of sign, preservative, and cause of animal health. Does the word ―being‖ exhibit the same order of rationes when predicated of substance and accident? This is the central point of contention that Cajetan sees between himself and Scotus (―in hoc pendet tota quaestio inter nos et Scotum‖). We might say that it is not about the analogy of being but the analogy of "being". At stake in this question of 34 analogy is the concept or ratio of being – which is to say, as Cajetan clarifies earlier in his commentary, the signification of the word ―being.‖ 3 Cajetan recapitulates at some length arguments from Scotus for the position that ―being‖ is univocal (section 19). He gives five distinct arguments (from Scotus's Oxford commentary on the Sentences, Book I, dist. III, qq. 1 & 3; dist. 8, q. 3 4 ), presumably ones that would be familiar to Scotists and to critics of Scotus. To summarize them briefly: (S1) We can be certain that something is a being while doubting whether it is God or a creature, finite or infinite, substance or accident; so the concept of being must be other than these, but included in these. 5 (S2) We can learn about God from creatures, but whatever concepts we have that apply to God were acquired from objects illuminated in the phantasms acquired from creatures, and any such objects must be essentially or virtually contained in the phantasms. 6 (S3) Again regarding theological discovery: reflection about God depends on attending to the ratio of something, stripping away the imperfections, and attributing to it the highest perfections; but we must start with the same formal ratio (or concept), which is therefore univocal to both perfect and imperfect beings. 7 (S4) We have quidditative knowledge of substance, but we only know substance via accidents, not directly 8 ; so the concept of substance must be abstracted from the accident. 9 3 ―It is the same to speak of the concept of being as to speak of the signification of „being‟‖ (idem est loqui de conceptu entis et de significatione ejus), §14. Alternatively, ―It is the same to speak of  being's concept as to speak of its signification.‖ 4 The Laurent edition of Cajetan refers to Scotus's q. 2 of d. 8, but the relevant text is clearly q. 3, and Cajetan gets the reference correct in his commentary on ST 13.5. 5 Cf. Duns Scotus, Commentaria Oxoniensia, I, d. 3, qq. 1&2, a. 4 (ed. Garcia, Florence, 1912), arg. #1, p. 309-310; cf. d. 8, q. 3, a. 1 [#624, pp. 593-594]. 6 Cf. Duns Scotus, Comm. Ox., d. 3, q. 1-2, a. 4, arg. #2, p. 311; also d. 8, q. 3, a. 1 (#623. p 591). 7 Cf. Duns Scotus, Comm. Ox., d. 3, q. 1-2, a. 4, arg. #3, pp. 311-312; cf. d. 8, q. 3, a. 1 (#625, pp. 595596). 8 As Scotus argues and Cajetan repeats: otherwise, for instance, we would be able to know by natural reason that the substance of bread is not present in the consecrated host! 9 Duns Scotus, Comm. Ox. d. 3, q. 3, a. 2, pp. 338-339: ―quod Deus non est a nobis cognoscibilis naturaliter nisi ens sit univocum creato et Increato, ita potest argui de substantia et accidente; cum enim substantia non immutet immediate intellectum nostrum ad aliquam intellectionem sui, sed tantum accidens sensibile, sequitur quod nullum conceptum quidditativum habere poteribus de ea, nisi sit aliquis talis qui posit abstrahi a conceptu accidentis: sed nullus talis quidditativus abstrahibilis est a conceptu accidentis, nisi conceptus entis; ergo etc.‖ P. 339 discusses the bread and the host on the altar – if we 35 (S5) Lastly, Cajetan points out that Scotus appeals to several textual authorities, of which Cajetan names Aristotle, Avicenna, and Algazali. Cajetan's longest discussion here is of a passage from Aristotle's Metaphysics (Book II), when Aristotle says (on Scotus's interpretation) that comparison of degree implies a univocal predication. (Met. II.1, 993b23-25) (Cajetan ends his summary by saying that the other authorities cited by Scotus, which he will not summarize, only prove the otherness (alietas) of being, not the univocation of being – i.e., that they show that there is a distinct concept of being, but not that the concept is univocal.) In these arguments, the attention to concept acquisition, judgments of comparison, certainty and doubt, and inference all reinforce that the essential issue for Cajetan, as well as for Scotus, is not metaphysical but epistemological or semantic. After stating these five arguments, Cajetan gives three reductio arguments against Scotus's conclusion that being is univocal (sect. 20). These do not resolve the issue and do not give Cajetan's full position, but they offer reasons to reject Scotus's conclusion. Effectively, they constitute an extended sed contra in the overall dialectical structure of the question. Briefly summarized, Cajetan's arguments are as follows: (C1) Accident defined insofar as it is being includes substance in its ratio, but substance as being does not include accident in its ratio – therefore being does not have the same ratio as predicated of substance and accident. (C2) If ―being‖ is univocal, it is a genus; but this leads to difficulties – such as that it would be included in both the definition of the genus and the definition of the difference (insofar as both are beings), but then a full definition of a species (including both genus and difference) would be nugatory. (C3) If being is a genus term, then it falls within the definition of substance, and so of man, which is contrary to Aristotle's teaching. Following these arguments, Cajetan gives (what he claims is) the teaching of Saint Thomas (sect. 21); one might think of this as the corpus or main reply to the question. I will outline that position here, keeping in mind that my object is not to articulate fully Cajetan's teaching on analogy, but only to highlight those features pertinent to Cajetan's dialectical deployment of Scotus. Cajetan describes analogy as a mean between univocation and equivocation. Following the structure of Aristotle's definitions from the beginning of the Categories, he gives definitions of the univocal, then of the equivocal, describing them as having a common name which refers to different things by means of concepts (rationes) either wholly the same or wholly different. In the mean of analogy, there is a common name ―and the could know substance immediately, ―sequeretur quod quando susbtantia non esset praesens posset naturaliter cognosci non esse praesens; et ita naturaliter posset cognosci in hostia Altaris consecrate non esse substantiam panis: quod est manifese falsum.‖ 36 ratio corresponding to that name is in one sense the same and in one sense different, or is the same in a qualified sense, and different in a qualified sense.‖ Cajetan then proceeds to distinguish two ways that the ratio can be somehow the same and somehow different: either (1) because there are two rationes with a determinate relation to each other, or (2) because there are two rationes which are proportionally similar. In other words, the secundum quid similarity between two concepts in one case is that one concept has a determinate relation to another, while the secundum quid similarity in the other case is ―not that the analogue is predicated simply of the primary analogate and of others relative to the primary, but because they have a concept or ratio which is the same in a qualified sense, owing to the sameness of proportion which is found in them, and different in a qualified sense, owing to the diversity of the given natures with these proportions‖ (emphasis added). These are the two modes of analogy Cajetan will later (in De Nominum Analogia) call analogy of attribution and analogy of proper proportionality. Although he doesn't use those terms here (and he here doesn't make the further claim of De Nominum Analogia that one is a more genuine or proper mode of analogy), we can see that analogy of proper proportionality is a more genuine or proper mean between univocation and equivocation. This becomes clear when Cajetan offers two corollaries or conclusions of his analysis: (1) being is analogous in both modes when predicated of substance and accident; and (2) being is analogous only in the latter mode when predicated of God and creatures. For the second conclusion, Cajetan cites the authority of Aquinas's De Veritate 2.11, but textual support seems secondary; Cajetan's semantic rationale is clear: analogy of proportionality is not a form of univocation (because there is a proportional relationship, not specific or generic identity or some other determinate relationship, between creatures and God), but is sufficiently unified – proportionally unified – to warrant inferences from creatures to God. Cajetan even cites the authority of Aristotle for his conviction that proportional unity is sufficient for scientific inference. The significance of this as a response to the arguments from Scotus is clear. Scotus argued for univocity in order to preserve the possibility of knowledge (as judgment or assent, and as discursive inference) that would be threatened by error or fallacy if the relevant key term ―being‖ were equivocal. Cajetan's response is that ―it is not necessary to say that ―being‖ is univocal in order for it to have attributes that ground a contradiction (i.e. when affirmed and denied of the same thing) [ens non oprtet poni univocum ad hoc quod passiones habeat et contradictionem fundet...].‖ Instead, unity of proportion suffices. Cajetan finishes the question by making this implicit response to Scotus explicit, giving careful replies to the objections, that is, responding to each of Scotus's five arguments for the univocity of being (section 21a): Ad (S1) To the argument about the possibility of having certainty with respect to one concept while doubting others, Cajetan replies that being is a concept distinct 37 from or other than the concept of substance and accident, but it is not univocal to them. Ad (S2) To the argument about the content of an abstracted concept being already contained in the phantasm, Cajetan replies that we can gain a concept that is not itself already in the phantasm, because the phantasm does not have to contain the cause virtually or essentially; the phantasm of an effect can contain the concept of the cause participatively – i.e. insofar as the cause is proportionally similar to the effect (cf. Cajetan's commentary on ST I, 13.5, section X). Ad (S3) To the argument about purifying a ratio of its imperfections, Cajetan says that the process can involve an analogous or only proportionally unified formal ratio. In other words, the result of the ―purification‖ process is not the identical concept purified, but a new concept proportionally similar to the original concept. Ad (S4) To the argument about only accidents modifying the intellect, Cajetan responds that substance does modify the intellect by its proper species, and not only by the species of accidents. 10 Ad (S5) Lastly, regarding Scotus's appeal to textual authority, Cajetan offers reinterpretations of the relevant texts; in particular, concerning Aristotle, Cajetan invokes a principle that a medium compared to an extreme takes on the characteristics of the opposite extreme 11 ; so in contrasting an analogical term to an equivocal term, Aristotle emphasized unity, and indeed comparison (e.g. of greater or lesser) does imply a unity in the standard of comparison, but not univocation. Again, proportional unity suffices. At this point let me highlight some general points about Cajetan's use of Scotus in q. 3 of the De Ente et Essentia commentary. First, Scotus figures quite prominently to frame the objections, setting up a set of problems that Cajetan thinks a Thomistic account of analogy must solve. (It seems that is not especially relevant that Scotus developed his position against Henry of Ghent, since Scotus's arguments serve equally well as objections to Aquinas's position.) Second, while it is the univocity of being that is at stake, in Scotus's arguments and Cajetan's response the issue is logical, not metaphysical or theological. When Cajetan does treat the metaphysical and theological questions, it is as different applications of logical distinctions. Third, the semantic concerns intensified by Scotus all pertain to how an analogical concept could have sufficient unity to ground knowledge without being univocal. A non-univocal concept, for Scotus, called into question the intelligibility of individual concepts, the sense of 10 But it does so through accidents, which is why the accidents of bread can still give the impression of the substance of bread, much as they nourish us! 11 Cajetan invoked the same principle earlier in sect. 21. 38 particular judgments, and the validity of inferences in discursive reasoning. Cajetan's response boils down to the position that proportional unity is sufficient to do the work that Scotus had assigned only to univocity. There is not one analogical concept, but two concepts whose proportional similarity allows them to function as if they are one. (And Cajetan's twice-invoked warning about the mean looking like an extreme acknowledges that the analogue may seem univocal, but only because it has sufficient unity to be differentiated from what is equivocal.) De Nominum Analogia (1498) Cajetan's separate, dedicated treatise on analogy was written three years after his commentary on De Ente et Essentia. A distinction between modes of analogy, and a preference for analogy of proportionality – these are the main teachings for which his treatise ―on the analogy of names‖ is remembered, but as we have seen these were already present in outline in the De Ente commentary's question on univocation. In the treatise, these teachings are more systematically worked out, and the context is even more explicitly a logical or semantic project. Indeed, the treatise on analogy could almost be read as an extended appendix to Cajetan's Categories commentary (written earlier the same year), where he mentioned analogy briefly in the traditional context of the definition of equivocation, and promised to treat further questions about analogy in a separate work. 12 De Nominum Analogia is structured to offer a treatment of analogy through the three parts of logic. 13 Here explicit attention to Scotus is much more muted. Scotus is not named early on, although presumably some of his arguments are in the background. The general question that motivates the treatise – to describe the unity of the analogical concept – shows attention to Scotus's concerns. And certainly some chapters start by posing problems that could be traced to Scotistic objections. Chapter 5 begins by posing a question about how abstraction works for analogy. Chapter 6 begins with a question about how an analogical predicate can be superior – that is, universal without being generic and so univocal. 14 In the discussion of comparison in Chapter 8, Cajetan says – in what surely sounds like a reference to Scotists – that ―it is believed by many‖ that there can't be comparison of greater or lesser without something [univocally] common. But Scotus is not mentioned by name in De Nominum Analogia until the penultimate chapter, when the semantics of analogy is applied to discursive reasoning in order to 12 Cajetan, Commentaria in Praedicamenta Aristotelis, ed. M.H.Laurent (Rome, 1939), p. 11: ―Quot autem modis contingat variari analogiam et quomodo, nunc quum summarie loquimur, silentio pertransibimus, specialem de hoc tractatum, si Deo placuerit, cito confecturi.‖ 13 Cf. Joshua P. Hochschild, ―The Rest of Cajetan's Analogy Theory: De Nominum Analogia chapters 411,‖ International Philosophical Quarterly 45 (2005): 341-356. 14 Also in ch. 6, in sect. 69, Cajetan discusses an objection which he says commits the fallacy of the consequent; in his commentary on ST 13.5 Cajetan attributes this same objection to Scotus. 39 address ―how there is scientific knowledge [scientia] of the analogue‖ (ch. 10). Scotus and his followers are referred to obliquely in sect. 104 (―it appears to some that there cannot be science of the analogue...‖) and Scotus is finally named in sect. 106 as defending this position. Cajetan also presents Scotus's definition of a univocal concept in sect. 113: ―I call a univocal concept what is one in such a way that its unity suffices for contradiction when it is affirmed and denied of the same thing.‖ 15 Cajetan finds this definition of univocity inadequate. Scotus ―either poorly explained the univocal concept, or contradicted himself‖ – i.e. since proportional unity is sufficient to preserve the reasoning, either this is a bad definition of univocity, or as a definition of ―univocity‖ it can't be used to say that analogical terms can't be used in scientific reasoning. 16 Cajetan's response to these issues, then, rests on an appeal to proportional unity. Such unity is sufficient for valid reasoning (again, as in the De Ente et Essentia commentary, citing Aristotle's Posterior Analytics, Bk. II). Here I offer an intermediate summary. In comparison with the extensive dialectical use of Scotus to frame the issue in the De Ente commentary, Cajetan's use of Scotus in the De Nominum Analogia is muted. This might seem coy, but it is reasonable, given that the goal here is to produce a treatise (not a polemic) expounding a theory (not just an interpretation of Aquinas or a reply to his critics). 17 It is quite clear that the work is motivated not just by the Scotistic objection to analogy but by the failure of other Thomists to adequately respond to it. (In the very first paragraph, Cajetan mentions three alternative inadequate accounts of the unity of the analogical concept.) It is also 15 Duns Scotus, Comm. Ox., I, d. 3, qq. 1&2, a. 4, ¶346 (309): ―...conceptum univocum dico qui ita est unus, quod eius unitas sufficit ad contradictionem affirmando et negando ipsum de eodem: sufficit etiam pro medio syllogistico, ut extrema unita in medio sic uno sine fallacia aequivocationis concludantur inter se uniri.‖ Cf. Duns Scotus, In Librum Praedicamentorum Quaestiones, q. 1: ―ubi est idem conceptus, ibi est univocatio.‖ Cf. Duns Scotus, In Libros Elenchorum Quaestiones, 2 (Vives 1891, 20a-25a). Presumably this identification of univocity with the power to mediate valid inference became typical of the Scotistic position; although I have conducted no systematic survey, the first Scotist Categories commentary I pulled off the shelf seems perfectly in line here: it treats analogy as ―equivocatio a consilio‖ where there are diverse significations, ―quorum unum dicit similitudinem vel proportionem ad aliud, nequaquam tamen convenientia in ratione formali una,‖ from which it is concluded that ―de aequivocis non est scientia quia deficient ab unitate.‖ Augustinus de Ferraria, Queastiones Super Librum Praedicamentorum Aristotelis, ed. Robert Andrews, Acta Universitatis Stockholmiensis (Studia Latina Stockholmiensia) XLV, 2000, pp. 23-24 (emphasis added). 16 I am unaware of philosophers before Scotus who explicitly defined univocity in terms of the ability to found a contradiction. More typical in the Aristotelian commentary tradition is the mention of the ability to found a contradiction as a feature of univocal terms, e.g. Simplicius, Commentary on Aristotle‟s Categories, 34. 7-11 (On Aristotle‟s ―Categories 1-4,‖ trans. Michael Chase, Cornell University Press, 2003, p. 48). But this is still compatible with treating analogous terms as a mean between univocation and equivocation, exhibiting some features of both. 17 It is worth noting also that Scotus is not mentioned in Cajetan's letter De Conceptu Entis (1509) which offers clarifications of, and is traditionally printed with, the treatise on analogy. 40 true that it would be difficult to find in Aquinas a direct answer to Scotus's concern. Although Aquinas clearly saw that analogy required semantic attention, his own discussions of the semantic functions of analogical terms remain unsystematic and incomplete. 18 Hence Cajetan sensed the need for an independent treatise, rather than a simple commentary or compilation of texts. But although Scotus is named only at the end, the influence of Scotus through the whole spectrum of logical or semantic concerns – from the semantics of terms to the structure of discursive reasoning – is clear. And while Cajetan's ultimate goal, like Scotus, is to explain the possibility of scientific reasoning, Scotus's error is traced to an inadequate definition of univocation and a failure to recognize proportional unity as a legitimate and relevant kind of unity. Commentary on the Summa Theologiae (1507?) Our last text to consider is Cajetan's commentary on article 5 of question 13 of Aquinas's Summa Theologiae, on whether names are applied to God and creatures univocally. Cajetan defends at length the structure of Aquinas's argument for the negative. Scotus is named in sect. IX, for his ―many arguments‖ from I Sent., d. 3, q. 1 and 3, and d. 8, q. 3 – the same passages as discussed at length in the De Ente commentary. Cajetan refers his readers to that commentary, and here only briefly describes four of Scotus's arguments: (T1) We can have certainty of one concept while doubting another concept [=(S1) above] (T2) In gaining knowledge of God, one formal ratio is stripped of imperfections [una ratione formali] [=(S3) above] (T3) God is known by a simple concept [naturaliter cognoscibilis aliqu simplici conceptu] contained either essentially or virtually in what is in the phantasm [=(S2) above] (T4) Comparison implies univocation [=(S5) above; Cf. DNA ch. 8] Cajetan offers responses to each of these arguments (section X): Ad (T1) It is a sophisma consequentis to say that the community of the concept implies univocation. Univocation implies community, but community does not imply univocation. Both univocals and analogues are superior to inferiors, but univocals are superior as prescinding from inferiors, while 18 See Joshua P. Hochschild, ―Did Aquinas Answer Cajetan's Question? Aquinas's Semantic Rules for Analogy and the Interpretation of De Nominum Analogia,‖ Proceedings of the American Catholic Philosophical Association 77 (2003): 273-288. 41 analogues are superior as containing them both. (Cajetan refers to De Nominum Analogia, where he makes these arguments in ch. 4.) Ad (T2) The ratio is one not simply, but by analogy (ratione una non simpliciter, sed secundum analogiam); some concepts can be ―polished‖ to apply to God (analogically), other concepts (like stone) cannot be so polished since they always contain imperfection. (For Scotus on sapiens vs. lapis, cf. d. 8, q. 3, a. 1, #626, p. 596.) Ad (T3) In addition to essential or virtual inclusion in the phantasm, there is a third mode of inclusion, by participation or imitation (participative vel imitative) [cf. De Nominum Analogia 90, 92, which mentions participation while discussing comparison] Ad (T4) There is comparison of the analogue, which is not an equivocal but a mean between the equivocal and the univocal, thanks to a unity that is proportional, not simple. (This is a topic in Ch. 8 of De Nominum Analogia, to which Cajetan refers.) So here in the Summa commentary, the extended, explicit dialectical engagement with Scotus is restored after being dropped in the treatise; but Cajetan's general theoretical position is the same. 19 The arguments are indeed pared down, with reference made both to the treatise on analogy and commentary on De Ente et Essentia for further elaboration. And here, even before mentioning Scotus, Cajetan spends more time describing the proportional relationship between concepts, how such concepts are acquired, and how they function in theological reasoning. Conclusion In Cajetan's treatment of analogy, Scotus's position presented a semantic problem, calling into question the very possibility of analogy as a mean between univocation and equivocation. As Scotus would have it, a concept is per se univocal. Univocation thus involves one concept, equivocation involves two, but there is no room for analogy as a mean between these two alternatives. In responding to this challenge, Cajetan in a sense concedes that a concept is strictly speaking univocal, but he insists that two concepts that are different can be proportionally one. In this case, one can speak of ―a‖ concept which is an analogical concept, just to the extent that the unity of this ―one‖ concept is only proportional unity. Cajetan's response, then, depends on a metaphysical distinction between kinds of unity. The success of Cajetan's response rests entirely on the success of his appeal to the reality of proportionally unified concepts. 19 Cajetan does provide an alternative way of describing the relationship of participation, i.e. as ―imitation.‖ 42 As a solution to Scotus' semantic challenge, Cajetan's teaching on proportional unity is fully present in the earliest relevant text, in the commentary on De Ente et Essentia. What he says in later writings does not modify or substantially add to what is found there. The De Nominum Analogia provides more systematic attention to the relevant semantics and epistemology, especially with its discussion of concept acquisition, judgment, and discursive reasoning. The discussion in the Summa Theologiae commentary adds further considerations about the acquisition of theological concepts. One might say that this attention to concept acquisition and reasoning extends, rather than replaces, Aquinas's attention to the role of judgment in analogy. Scotus's views on univocity highlighted the semantic pecularity of analogy, and Cajetan saw this as a dialectically useful opportunity to defend a Thomistic understanding of thought and signification, appealing to a metaphysical distinction – between pure and proportional unity – in order to elaborate the semantics of analogy further than Aquinas ever did.