The Semantics of Analogy: Rereading Cajetan's De Nominum Analogia (review)

In this work, Joshua Hochschild presents the semantic principles of Cajetan's understanding of analogy, arguing that they should be understood on their own terms and not as a commentary on Aquinas despite the inevitable comparisons between the two thinkers. In the first three chapters, Hochschild argues convincingly that Cajetan's discussion is aimed to answer specific questions that were occasioned by John Duns Scotus's arguments against analogy and not solely as an attempt to interpret Aquinas. Hochschild summarizes Scotus's arguments as objections to the use of analogy in scientific reasoning, which his opponents thought must be used in order for metaphysics to remain a science (39). More specifically, Scotus argues that only a univocal treatment of being could preserve such reasoning.

In chapter 4, Hochschild argues that Aquinas does not provide an answer to Scotus's challenge, although a Thomistic answer could be formulated based on his writings (76). Despite this charitable admission, however, Hochschild appears to gainsay any such solution (contra Ralph McInerny) by claiming the following: "The proposed rule that analogy involves a common res significata and diverse modi significandi does not help us explain why some analogical terms can be used in syllogisms without causing the fallacy of equivocation" (76). As an example, Hochschild cites the analogical use of health, which was a favourite of Aquinas's, and then claims the following: "In the syllogism, 'Whatever is on your plate is healthy, and whatever is healthy is alive; therefore, whatever is on your plate is alive,' the premises, insofar as they are plausibly true, contain the term 'healthy' in different analogical senses, and this is precisely the reason why the conclusion does not follow from the premises" (76).

A Thomistic approach to analogy would argue that there is a focal meaning of "health" that is implied in its varied usages while those usages pick out different aspects of it, i.e. "Whatever is on your plate is the cause of health and is thus healthy," "Whatever is the subject of health is alive and thus an animal is healthy," etc. Nevertheless, it is the same health that is being referred to in both examples, even though "healthy" is not univocal. Thus it would seem that Aquinas would have to admit that in the above syllogism, "healthy" is not used in the same sense. However, he would argue that the two senses of "healthy" are related to one thing, "health." So the various uses of "healthy" can be reduced to aspects of a single sense, and the syllogism could be reconfigured along those lines. This brief observation is not enough to address adequately either Scotus or Cajetan's concerns. Nevertheless, Aquinas specialists would do well to read Hochschild's analysis, as there is much here that could prompt further fruitful discussions.

In chapters 5 through 7, Hochschild presents Cajetan's semantic principles, arguing that the response to the Scotistic challenge is to be found in an analogy of "non-generic likeness" or "proportional unity." Cajetan argues that it is the only species of analogy that can overcome Scotus's objection. That is, a non-metaphorical proportional unity, such that the ratio signified by the analogates is said of each of them proportionally, prevents the fallacy of four terms (126; 174). As an example, Cajetan offers the following syllogism: "Every simple perfection is in God, wisdom is a simple perfection, therefore [wisdom is in God]" (162). The proportional similarity of the concepts of the term "wisdom" as it is applied to creatures and to God is thought to be sufficient to keep the syllogism from lapsing into equivocation. Of course, Thomists will shudder at the assertion that "wisdom" is a matter of proportionality between creator and creatures, since Aquinas thinks that the res significata and the modus significandi make up the ratio of a term. More specifically, the modus significandi of perfections that are applied to God is different from...